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Sample records for cardioverter defibrillator cross-validation

  1. Optimal Implantable Cardioverter Defibrillator Programming.

    Science.gov (United States)

    Shah, Bindi K

    Optimal programming of implantable cardioverter defibrillators (ICDs) is essential to appropriately treat ventricular tachyarrhythmias and to avoid unnecessary and inappropriate shocks. There have been a series of large clinical trials evaluating tailored programming of ICDs. We reviewed the clinical trials evaluating ICD therapies and detection, and the consensus statement on ICD programming. In doing so, we found that prolonged ICD detection times, higher rate cutoffs, and antitachycardia pacing (ATP) programming decreases inappropriate and painful therapies in a primary prevention population. The use of supraventricular tachyarrhythmia discriminators can also decrease inappropriate shocks. Tailored ICD programming using the knowledge gained from recent ICD trials can decrease inappropriate and unnecessary ICD therapies and decrease mortality.

  2. Azygos Vein Lead Implantation For High Defibrillation Thresholds In Implantable Cardioverter Defibrillator Placement

    Directory of Open Access Journals (Sweden)

    Naga VA Kommuri

    2010-01-01

    Full Text Available Evaluation of defibrillation threshold is a standard of care during implantation of implantable cardioverter defibrillator. High defibrillation thresholds are often encountered and pose a challenge to electrophysiologists to improve the defibrillation threshold. We describe a case series where defibrillation thresholds were improved after implanting a defibrillation lead in the azygos vein.

  3. Concerns about the implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; van Domburg, Ron T; Theuns, Dominic A M J

    2005-01-01

    Patients with an implantable cardioverter defibrillator (ICD) are at increased risk of anxiety disorders. In turn, anxiety has been identified as a precipitant of ventricular arrhythmias. Anxiety may in part be attributed to concerns about the ICD firing, but the relationship between ICD concerns......, psychological morbidity, and shocks has not been systematically investigated. We examined the relative importance of experienced shocks versus subjective concerns about the ICD as determinants of anxiety and depressive symptoms in ICD patients....

  4. Implantable cardioverter defibrillator implantation in children in The Netherlands

    NARCIS (Netherlands)

    Ten Harkel, ADJ; Blom, NA; Reimer, AG; Tukkie, R; Sreeram, N; Bink-Boelkens, MTE

    To evaluate the indications, underlying cardiac disorders, efficacy and complications involved with implantable cardioverter-defibrillators (ICDs) in paediatric patients in The Netherlands, the records of all patients aged 18 years or younger who underwent ICD placement were reviewed

  5. Implantable cardioverter defibrillator implantation in children in The Netherlands

    NARCIS (Netherlands)

    ten Harkel, A. Derk Jan; Blom, Nico A.; Reimer, Annette G.; Tukkie, Raymond; Sreeram, Narayanswami; Bink-Boelkens, Margreet T. E.

    2005-01-01

    To evaluate the indications, underlying cardiac disorders, efficacy and complications involved with implantable cardioverter-defibrillators (ICDs) in paediatric patients in The Netherlands, the records of all patients aged 18 years or younger who underwent ICD placement were reviewed

  6. Gender differences in anxiety and concerns about the cardioverter defibrillator

    DEFF Research Database (Denmark)

    Spindler, Helle; Johansen, Jens B; Andersen, Kirsten Krogh

    2009-01-01

    Little is known about gender differences in the response to implantable cardioverter defibrillator (ICD) therapy. We compared female and male ICD patients on anxiety, depression, health-related quality of life (HRQL), ICD concerns, and ICD acceptance.......Little is known about gender differences in the response to implantable cardioverter defibrillator (ICD) therapy. We compared female and male ICD patients on anxiety, depression, health-related quality of life (HRQL), ICD concerns, and ICD acceptance....

  7. Pacemakers and implantable cardioverter defibrillators - general and anesthetic considerations

    Directory of Open Access Journals (Sweden)

    Amy G. Rapsang

    2014-06-01

    Full Text Available A pacemaking system consists of an impulse generator and lead or leads to carry the electrical impulse to the patient's heart. Pacemaker and implantable cardioverter defibrillator codes were made to describe the type of pacemaker or implantable cardioverter defibrillator implanted. Indications for pacing and implantable cardioverter defibrillator implantation were given by the American College of Cardiologists. Certain pacemakers have magnet-operated reed switches incorporated; however, magnet application can have serious adverse effects; hence, devices should be considered programmable unless known otherwise. When a device patient undergoes any procedure (with or without anesthesia, special precautions have to be observed including a focused history/physical examination, interrogation of pacemaker before and after the procedure, emergency drugs/temporary pacing and defibrillation, reprogramming of pacemaker and disabling certain pacemaker functions if required, monitoring of electrolyte and metabolic disturbance and avoiding certain drugs and equipments that can interfere with pacemaker function. If unanticipated device interactions are found, consider discontinuation of the procedure until the source of interference can be eliminated or managed and all corrective measures should be taken to ensure proper pacemaker function should be done. Post procedure, the cardiac rate and rhythm should be monitored continuously and emergency drugs and equipments should be kept ready and consultation with a cardiologist or a pacemaker-implantable cardioverter defibrillator service may be necessary.

  8. Intra-operative defibrillation testing and clinical shock efficacy in patients with implantable cardioverter-defibrillators

    DEFF Research Database (Denmark)

    Bänsch, Dietmar; Bonnemeier, Hendrik; Brandt, Johan

    2015-01-01

    AIMS: This trial was designed to test the hypothesis that shock efficacy during follow-up is not impaired in patients implanted without defibrillation (DF) testing during first implantable cardioverter-defibrillator (ICD) implantation. METHODS AND RESULTS: Between February 2011 and July 2013, 107...

  9. Implantable cardioverter defibrillator specific rehabilitation improves health cost outcomes

    DEFF Research Database (Denmark)

    Berg, Selina Kikkenborg; Zwisler, Ann-Dorthe; Koch, Mette Bjerrum

    2015-01-01

    OBJECTIVE: The Copenhagen Outpatient ProgrammE - implantable cardioverter defibrillator (COPE-ICD) trial included patients with implantable cardioverter defibrillators in a randomized controlled trial of rehabilitation. After 6-12 months significant differences were found in favour of the rehabil...... was -6,789 USD/-5,593 Euro in favour of rehabilitation. CONCLUSION: No long-term health outcome benefits were found for the rehabilitation programme. However, the rehabilitation programme resulted in a reduction in total attributable direct costs....... of the rehabilitation group for exercise capacity, general and mental health. The aim of this paper is to explore the long-term health effects and cost implications associated with the rehabilitation programme; more specifically, (i) to compare implantable cardioverter defibrillator therapy history and mortality...... between rehabilitation and usual care groups; (ii) to examine the difference between rehabilitation and usual care groups in terms of time to first admission; and (iii) to determine attributable direct costs. METHODS: Patients with first-time implantable cardioverter defibrillator implantation (n = 196...

  10. Daily remote monitoring of implantable cardioverter-defibrillators

    DEFF Research Database (Denmark)

    Hindricks, Gerhard; Varma, Niraj; Kacet, Salem

    2017-01-01

    Aims: Remote monitoring of implantable cardioverter-defibrillators may improve clinical outcome. A recent meta-analysis of three randomized controlled trials (TRUST, ECOST, IN-TIME) using a specific remote monitoring system with daily transmissions [Biotronik Home Monitoring (HM)] demonstrated...

  11. Impact of carvedilol and metoprolol on inappropriate implantable cardioverter-defibrillator therapy

    DEFF Research Database (Denmark)

    Ruwald, Martin H; Abu-Zeitone, Abeer; Jons, Christian

    2013-01-01

    The goal of this study was to evaluate the effects of carvedilol and metoprolol on the endpoint of inappropriate implantable cardioverter-defibrillator therapy in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization Therapy) study....

  12. Cardioverter-defibrillator implantation in myeloma-associated cardiac amyloidosis.

    Science.gov (United States)

    Campanile, Alfonso; Sozzi, Fabiola B; Canetta, Ciro; Danzi, Gian Battista

    2013-01-01

    A 62-year-old woman with multiple myeloma and light-chain amyloidosis with significant heart involvement developed an in-hospital cardiac arrest. After cardiopulmonary resuscitation, a stable sinus rhythm without any cerebral damage was restored, and the patient was admitted to the coronary care unit. A cardioverter-defibrillator was implanted, and it successfully intervened in two sustained ventricular tachycardia episodes and one ventricular fibrillation episode, which were recorded during hospitalization. After achieving discrete cardiac compensation, the patient was transferred to the emergency medicine department where she underwent chemotherapy for multiple myeloma. The patient died 40 days after admission from refractory heart failure. In the literature, there are studies that describe the use of cardioverter-defibrillator implantation in cardiac amyloidosis; however, at present, there is no evidence of a beneficial effect on survival with the use of this intervention. A high index of suspicion for amyloid heart disease and early diagnosis are critical to improving outcomes.

  13. Behavioral interventions in patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Habibović, Mirela; Burg, Matthew M; Pedersen, Susanne S.

    2013-01-01

    The implantable cardioverter defibrillator (ICD) is the first-line treatment for primary and secondary prevention of sudden cardiac death. A subgroup of patients experience psychological distress postimplant, and no clear evidence base exists regarding how best to address patients' needs. The aim...... of this critical review is to provide an overview of behavioral interventions in ICD patients to date, and to delineate directions for future research using lessons learned from the ongoing RISTA and WEBCARE trials....

  14. Pre-implantation implantable cardioverter defibrillator concerns and Type D personality increase the risk of mortality in patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; van den Broek, Krista C; Erdman, Ruud A M

    2010-01-01

    Little is known about the influence of psychological factors on prognosis in implantable cardioverter defibrillator (ICD) patients. We examined the influence of the distressed personality (Type D) and pre-implantation device concerns on short-term mortality in ICD patients.......Little is known about the influence of psychological factors on prognosis in implantable cardioverter defibrillator (ICD) patients. We examined the influence of the distressed personality (Type D) and pre-implantation device concerns on short-term mortality in ICD patients....

  15. Depressive symptoms in patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S; Andersen, Christina M; Denollet, Johan

    2018-01-01

    OBJECTIVE: Patients with an implantable cardioverter defibrillator (ICD) and co-morbid depression are at greater risk of poor quality of life and premature death. We examined if treatment expectations predict depressive symptoms 12months post implant. METHODS: First-time implant patients from...... of 12-months depressive symptoms: Model 1: Negative treatment expectations (β=0.202; p=0.020) and baseline depression (β=0.376; pdepression (β=0.350; p....051). Model 3: Baseline depression (β=0.353; p

  16. Making post-mortem implantable cardioverter defibrillator explantation safe

    DEFF Research Database (Denmark)

    Räder, Sune B E W; Zeijlemaker, Volkert; Pehrson, Steen

    2009-01-01

    that the resting voltage over the operating person would not exceed 50 V. CONCLUSION: The use of intact medical gloves made of latex, neoprene, or plastic eliminates the potential electrical risk during explantation of an ICD. Two gloves on each hand offer sufficient protection. We will recommend the use......AIMS: The aim of this study is to investigate whether protection with rubber or plastic gloves during post-mortem explantation of an implantable cardioverter defibrillator (ICD) offers enough protection for the explanting operator during a worst-case scenario (i.e. ICD shock). METHODS AND RESULTS...

  17. Management of Implantable Cardioverter Defibrillator Recipients: Care Beyond Guidelines.

    Science.gov (United States)

    Philippon, François; Sterns, Laurence D; Nery, Pablo B; Parkash, Ratika; Birnie, David; Rinne, Claus; Mondesert, Blandine; Exner, Derek; Bennett, Matthew

    2017-08-01

    This companion article is intended to address common clinical scenarios in patients with implantable defibrillators that were not addressed in the 2016 Canadian Cardiovascular Society/Canadian Heart Rhythm Society implantable cardioverter defibrillator guidelines including recommendations for device programming to improve detection, to minimize shocks (appropriate and inappropriate), and to minimize ventricular pacing. Important issues at the time of replacement such as device prescription, technical aspects (vascular access, extraction), and management of components on advisories are also discussed. Finally, common clinical scenarios such as management of patients with terminal illnesses, recurrent ventricular tachycardia, electrical storms, catheter ablation for ventricular tachycardia, and system infection management are considered. The management of these patients requires a team approach and comprehensive knowledge surrounding these common clinical scenarios. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  18. Somatosensory amplification mediates sex differences in psychological distress among cardioverter-defibrillator patients

    DEFF Research Database (Denmark)

    Versteeg, Henneke; Baumert, Jens; Kolb, Christof

    2010-01-01

    The present study examined whether female patients with an implantable cardioverter defibrillator (ICD) report more psychological distress than male patients, and whether somatosensory amplification mediates this relationship. Design: Consecutive ICD patients (N = 241; 33% women) participating in...

  19. Correlation of geomagnetic activity with implantable cardioverter defibrillator shocks and antitachycardia pacing

    Czech Academy of Sciences Publication Activity Database

    Ebrille, E.; Konecny, T.; Konecny, D.; Špaček, R.; Jones, P.; Ambrož, Pavel; DeSimone, C.V.; Powel, B.D.; Hayes, D.L.; Friedman, P.A.; Asirvatham, S.J.

    2015-01-01

    Roč. 90, č. 2 (2015), s. 202-208 ISSN 0025-6196 Institutional support: RVO:67985815 Keywords : geomagnetic activity * implantable cardioverter defibrillator Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 5.920, year: 2015

  20. Driving safety among patients with automatic implantable cardioverter defibrillators.

    Science.gov (United States)

    Finch, N J; Leman, R B; Kratz, J M; Gillette, P C

    1993-10-06

    To determine the driving behavior of patients following the placement of automatic implantable cardioverter defibrillators (AICDs). Forty patients with AICDs (33 men, seven women; mean age, 62.7 years) responded to a questionnaire designed to ascertain driving behavior after hospital discharge. Despite medical advice never to drive again, 28 patients (70%) resumed driving, with the majority doing so by 8 months after AICD implantation. Of these, 11 (40%) identified themselves as the primary driver in their household. Fourteen (50%) drove daily. Two (7%) were driving and continued to drive during discharge of their AICDs. Twenty-five (91%) reported that they felt comfortable and safe while driving. A majority of patients with AICDs continue to drive after a proscription of this activity by health care workers.

  1. Psychological distress in patients with an implantable cardioverter defibrillator

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Shiga, MD

    2013-12-01

    Full Text Available Despite the effectiveness of an implantable cardioverter defibrillator (ICD, its implantation and concomitant therapies, including shocks, can induce psychological distress in patients. Depression has been observed in approximately 30% of ICD patients, and shocks may contribute to the persistence of depression. Anxiety is common, with reports of 24–87% of ICD patients experiencing symptoms of anxiety after implantation, and type D personality and ICD-related concerns may play important roles in the level of anxiety in ICD patients. However, the association between ICD shocks and anxiety is controversial. The prevalence of posttraumatic stress disorder (PTSD in ICD patients is approximately 20%, and type D personality, comorbidities, and frequent shocks may contribute to PTSD. It is also important to pay attention to the psychological distress in the partners of ICD patients.

  2. Higher defibrillation threshold in methamphetamine cardiomyopathy patients with implantable cardioverter-defibrillator

    Directory of Open Access Journals (Sweden)

    Rakesh Malhotra

    2017-11-01

    Full Text Available Introduction: Identification of patients with an increased risk of high defibrillation thresholds (DFTs is important in planning implantable cardioverter-defibrillator (ICD procedures. Clinical observations have suggested that patients with methamphetamine cardiomyopathy (MACMP have significantly elevated defibrillation thresholds. We hypothesized that MACMP patients would have higher DFT thresholds than controls and would require procedural changes during ICD implantation to accommodate higher thresholds. Methods: We identified consecutive patients with MACMP undergoing ICD implantation at the academic center from 2003 to 2007. We then compared DFTs against age-and sex-matched controls. Results: The MACMP (n = 10 group showed significantly increased DFT thresholds (23.7 ± 6.7 J compared with age and sex-matched controls (14.5 ± 4.6 J, p < 0.005. Additionally, patients with MACMP had evidence of more severe congestive heart failure, with increased B-type natrieutic protein (BNP levels (1173 ± 784 vs 260 ± 349, p = 0.02 and decreased left ventricular ejection fraction (LVEF (17.8 ± 9.4 vs 35.9 ± 15.2, p = 0.02. MACMP patients required high output devices than controls (50% versus 0%, p = 0.03. Differences between groups remained significant despite adjusting for LVEF. Conclusions: Planning for ICD implantation should take into consideration a history of methamphetamine abuse, mandating DFT testing and empiric consideration of high output devices for such patients. Keywords: Methamphetamine cardiomyopathy, Implantable cardioverter-defibrillatior, Defibrillation threshold testing, B-type natriuretic peptide, Ejection fraction

  3. Attrition and Adherence in a Web-Based Distress Management Program for Implantable Cardioverter Defibrillator Patients (WEBCARE): Randomized Controlled Trial

    DEFF Research Database (Denmark)

    Habibovic, M.; Cuijpers, P.; Alings, M.

    2014-01-01

    Background: WEB-Based Distress Management Program for Implantable CARdioverter defibrillator Patients (WEBCARE) is a Web-based randomized controlled trial, designed to improve psychological well-being in patients with an implantable cardioverter defibrillator (ICD). As in other Web-based trials, ...

  4. Clinical performance of different DF-4 implantable cardioverter defibrillator leads.

    Science.gov (United States)

    Sarrazin, Jean-François; Philippon, François; Sellier, Romain; André, Philippe; O'Hara, Gilles; Molin, Franck; Nault, Isabelle; Blier, Louis; Champagne, Jean

    2018-06-01

    Implantable cardioverter-defibrillator (ICD) DF-4 connectors have been introduced to facilitate defibrillator lead connection and to reduce the size of device header. There are limited data regarding the overall performance of those leads and no comparison between different ICD DF-4 leads. This is a cohort study of consecutive patients implanted with ICD DF-4 lead system at one University Centre between October 2010 and February 2015. A historical control group of patients with ICD DF-1 lead implantation was used for comparison. The following ICD DF-4 leads were evaluated: St. Jude Medical Durata 7122Q (St. Jude Medical, St. Paul, MN, USA), Medtronic Sprint Quattro Secure 6935 M (Medtronic Inc., Minneapolis, MN, USA), Boston Scientific Endotak Reliance 4-Site 0293 (Boston Scientific, Marlborough, MA, USA), and Boston Scientific Reliance 4-Front 0693. This study evaluated the acute and mid-term performances of those leads as well as complications. A total of 812 patients (age 63 ± 12 years, 80% male, left ventricular ejection fraction 31 ± 12%) underwent implantation of an ICD DF-4 lead. Acute and follow-up R-wave sensing and threshold were excellent. Compared to implantation, intrinsic R waves were higher at follow-up for Boston Scientific and Medtronic leads, and pacing lead impedances were lower for all leads at first follow-up (P < 0.001). The number of lead dislodgement or failure was similar between all leads. The estimated lead survival rates at 3 years were 95.6% for Boston Scientific Endotak 4-Site, 97.1% for Boston Scientific 4-Front, 97.7% for Medtronic Sprint Quattro, and 97.5% for St. Jude Durata (P  =  0.553). All ICD DF-4 leads had excellent acute and mid-term electrical performances. Longer follow-up will be necessary to confirm their sustained performance. © 2018 Wiley Periodicals, Inc.

  5. Antitachycardia pacing programming in implantable cardioverter defibrillator: A systematic review.

    Science.gov (United States)

    De Maria, Elia; Giacopelli, Daniele; Borghi, Ambra; Modonesi, Letizia; Cappelli, Stefano

    2017-05-26

    Implantable cardioverter defibrillator (ICD) programming involves several parameters. In recent years antitachycardia pacing (ATP) has gained an increasing importance in the treatment of ventricular arrhythmias, whether slow or fast. It reduces the number of unnecessary and inappropriate shocks and improves both patient's quality of life and device longevity. There is no clear indication regarding the type of ATP to be used, except for the treatment of fast ventricular tachycardias (188 bpm-250 bpm) where it has been shown a greater efficacy and safety of burst compared to ramp; 8 impulses in each sequence of ATP appears to be the best programming option in this setting. Beyond ATP use, excellent clinical results were obtained with programming standardization following these principles: extended detection time in ventricular fibrillation (VF) zone; supraventricular discrimination criteria up to 200 bpm; first shock in VF zone at the maximum energy in order to reduce the risk of multiple shocks. The MADIT-RIT trial and some observational registries have also recently demonstrated that programming with a widespread use of ATP, higher cut-off rates or delayed intervention reduces the number of inappropriate and unnecessary therapies and improves the survival of patients during mid-term follow-up.

  6. Battery longevity in cardiac resynchronization therapy implantable cardioverter defibrillators.

    Science.gov (United States)

    Alam, Mian Bilal; Munir, Muhammad Bilal; Rattan, Rohit; Flanigan, Susan; Adelstein, Evan; Jain, Sandeep; Saba, Samir

    2014-02-01

    Cardiac resynchronization therapy (CRT) implantable cardioverter defibrillators (ICDs) deliver high burden ventricular pacing to heart failure patients, which has a significant effect on battery longevity. The aim of this study was to investigate whether battery longevity is comparable for CRT-ICDs from different manufacturers in a contemporary cohort of patients. All the CRT-ICDs implanted at our institution from 1 January 2008 to 31 December 2010 were included in this analysis. Baseline demographic and clinical data were collected on all patients using the electronic medical record. Detailed device information was collected on all patients from scanned device printouts obtained during routine follow-up. The primary endpoint was device replacement for battery reaching the elective replacement indicator (ERI). A total of 646 patients (age 69 ± 13 years), implanted with CRT-ICDs (Boston Scientific 173, Medtronic 416, and St Jude Medical 57) were included in this analysis. During 2.7 ± 1.5 years follow-up, 113 (17%) devices had reached ERI (Boston scientific 4%, Medtronic 25%, and St Jude Medical 7%, P battery was significantly worse for Medtronic devices compared with devices from other manufacturers (94% for Boston scientific, 67% for Medtronic, and 92% for St Jude Medical, P battery longevity by manufacturer was independent of pacing burden, lead parameters, and burden of ICD therapy. There are significant discrepancies in CRT-ICD battery longevity by manufacturer. These data have important implications on clinical practice and patient outcomes.

  7. Spinal cord stimulation for refractory angina in patients implanted with cardioverter defibrillators: five case reports

    DEFF Research Database (Denmark)

    Enggaard, Thomas P; Andersen, Claus; Scherer, Christian

    2010-01-01

    Patients implanted with a cardioverter defibrillator (ICD) who are suffering from refractory angina pectoris could benefit from spinal cord stimulation (SCS) due to the well-documented pain relieving effect. However, the combined treatment remains controversial. The aim of the study is to report...... successful long-term treatment with SCS in five patients implanted with cardioverter defibrillators. The combined treatments with ICD and thoracic epidural electrical stimulation were used in five patients with refractory angina pectoris. During the procedure of the implantation, testing with the maximal...... for refractory angina pectoris can be performed in patients implanted with cardioverter defibrillators without interference. However, individual testing during implantation or re-programming the devices is mandatory in order to assess optimal safety in each patient....

  8. Dual chamber arrhythmia detection in the implantable cardioverter defibrillator.

    Science.gov (United States)

    Dijkman, B; Wellens, H J

    2000-10-01

    Dual chamber implantable cardioverter defibrillator (ICD) technology extended ICD therapy to more than termination of hemodynamically unstable ventricular tachyarrhythmias. It created the basis for dual chamber arrhythmia management in which dependable detection is important for treatment and prevention of both ventricular and atrial arrhythmias. Dual chamber detection algorithms were investigated in two Medtronic dual chamber ICDs: the 7250 Jewel AF (33 patients) and the 7271 Gem DR (31 patients). Both ICDs use the same PR Logic algorithm to interpret tachycardia as ventricular tachycardia (VT), supraventricular tachycardia (SVT), or dual (VT+ SVT). The accuracy of dual chamber detection was studied in 310 of 1,367 spontaneously occurring tachycardias in which rate criterion only was not sufficient for arrhythmia diagnosis. In 78 episodes there was a double tachycardia, in 223 episodes SVT was detected in the VT or ventricular fibrillation zone, and in 9 episodes arrhythmia was detected outside the boundaries of the PR Logic functioning. In 100% of double tachycardias the VT was correctly diagnosed and received priority treatment. SVT was seen in 59 (19%) episodes diagnosed as VT. The causes of inappropriate detection were (1) algorithm failure (inability to fulfill the PR

  9. Monitoring device acceptance in implantable cardioverter defibrillator patients using the Florida Patient Acceptance Survey

    DEFF Research Database (Denmark)

    Versteeg, Henneke; Starrenburg, Annemieke; Denollet, Johan

    2012-01-01

    Patient device acceptance might be essential in identifying patients at risk for adverse patient-reported outcomes following implantation of an implantable cardioverter defibrillator (ICD). We examined the validity and reliability of the Florida Patient Acceptance Scale (FPAS) and identified corr...

  10. Gender disparities in anxiety and quality of life in patients with an implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Habibović, Mirela; van den Broek, Krista C; Theuns, Dominic A M J

    2011-01-01

    A paucity of studies in implantable cardioverter-defibrillator (ICD) patients has examined gender disparities in patient-reported outcomes, such as anxiety and quality of life (QoL). We investigated (i) gender disparities in anxiety and QoL and (ii) the magnitude of the effect of gender vs. New...

  11. E-Health to Manage Distress in Patients With an Implantable Cardioverter-Defibrillator

    DEFF Research Database (Denmark)

    Habibović, Mirela; Denollet, Johan; Cuijpers, Pim

    2014-01-01

    UNLABELLED: The Web-based distress management program for patients with an implantable cardioverter-defibrillator (ICD; WEBCARE) was developed to mitigate distress and enhance health-related quality of life in ICD patients. This study investigated the treatment effectiveness at 3-month follow-up ...

  12. Implantable cardioverter defibrillator therapy for prevention of sudden cardiac death in children in the Netherlands

    NARCIS (Netherlands)

    Heersche, Jogien H. M.; Blom, Nico A.; van de Heuvel, Freek; Blank, Christiaan; Reimer, Annette G.; Clur, Sally-Ann; Witsenburg, Maarten; ten Harkel, A. Derk Jan

    2010-01-01

    INTRODUCTION: Implantable cardioverter defibrillator (ICD) therapy is increasingly used in children. The purpose of this multicenter study is to evaluate mid-term clinical outcome and to identify predictors for device discharge in pediatric ICD recipients. METHODS AND RESULTS: From 1995 to 2006, 45

  13. SUDDEN CARDIAC DEATH AND THE USE OF IMPLANTABLE CARDIOVERTER-DEFIBRILLATORS IN PEDIATRIC-PATIENTS

    NARCIS (Netherlands)

    SILKA, MJ; KRON, J; DUNNIGAN, A; DICK, M; BINKBOELKENS, M; ERICKSON, CC; JEDEIKIN, R; WETZEL, GT; VANHARE, GF; CAMPBELL, R; WALSH, E; SAUL, JP; SCHAFFER, MS; KARPAWICH, P; VOGEL, RL; BENSON, DW; DEAL, B; SCAGLIOTTI, D; STERBA, R; HORDOF, AJ; KRONGRAD, E; KANTER, RJ; EPSTEIN, M; COHEN, M; BEDER, S; HAMILTON, R; FOURNIER, A; HUBBARD, J; CHRISTIANSEN, JL; JENNINGS, J; VILLAFANE, J; PORTER, CBJ; CASE, C; GILLETTE, PC; BELAND, M; KUGLER, JD; OCONNOR, BK; ALLENDER, H; HERNDON, SP; SMITH, RT; BURTON, D; KURER, CC; BYRUM, C; GUAM, WE; FRIEDMAN, R; PERRY, JC; SCOTT, W; MEHTA, AV; PICKHOFF, AS; FISH, F; YEAGER, S; KAWABORI, [No Value; TRIPPLE, M; ROSENFELD, LE

    Background. During the past decade. the implantable cardioverter-defibrillator (ICD) has emerged as the primary therapeutic option for survivors of sudden cardiac death (SCD). Investigation of the clinical efficacy of these devices has primarily assessed outcome in adults with coronary artery

  14. Implantable Cardioverter Defibrillator Therapy for Prevention of Sudden Cardiac Death in Children in The Netherlands

    NARCIS (Netherlands)

    Heersche, Jogien H. M.; Blom, Nico A.; Van De Heuvel, Freek; Blank, Christiaan; Reimer, Annette G.; Clur, Sally-Ann; Witsenburg, Maarten; Ten Harkel, A. Derk Jan

    Introduction: Implantable cardioverter defibrillator (ICD) therapy is increasingly used in children. The purpose of this multicenter study is to evaluate mid-term clinical outcome and to identify predictors for device discharge in pediatric ICD recipients. Methods and Results: From 1995 to 2006, 45

  15. Undertreatment of anxiety and depression in patients with an implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Kupper, Nina; Theuns, Dominic A M J

    2012-01-01

    Twenty-five to 33% of patients with an implantable cardioverter-defibrillator (ICD) experience anxiety and depression, but it is not known whether their symptoms are adequately treated. We investigated (a) whether patients with clinically relevant symptoms of distress received appropriate treatme......, and (b) whether patients not treated for their emotional distress reported poorer health status using a prospective study design....

  16. Experiences of patients with implantable cardioverter defibrillator in Turkey: A qualitative study

    Directory of Open Access Journals (Sweden)

    Özgür Aslan

    2012-01-01

    Full Text Available Background. There has been an increase in the number of patients with implantable cardioverter defibrillator (ICD. It isimportant to understand ICD patients’ experiences with it.Aim. The aim of this study was to describe experiences of patients with implantable cardioverter defibrillator (ICD.Methodology. A qualitative approach was used. Focus group interviews were used to obtain data from 19 patients whowere implanted cardioverter defibrillator at two centers in Izmir, Turkey. The patients were assigned into four groups. Thedata was analyzed using qualitative content analysis.Results. The analysis revealed six main themes: activities of daily living, social life, familial relationships, emotionalchanges, implantable cardioverter defibrillator shocks and experiences with receiving information and counselling fromhealth care providers.Conclusions. It can be concluded that patients with ICD experience physical and psychological problems and are not offeredthe education they need. To reduce the fears of the patients and their families and to prepare them for possible life stylechanges, comprehensive training programs that start in the pre-implantation period and continue into the post-implantationperiod should be organized.

  17. Increased anxiety in partners of patients with a cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; VAN DEN Berg, Martha; Erdman, Ruud A M

    2009-01-01

    The partner of the implantable cardioverter-defibrillator (ICD) patient serves as an important source of support for the patient, which may be hampered if the partner experiences increased distress. We examined (1) potential differences in anxiety and depressive symptoms in ICD patients compared...

  18. Anxiety and risk of ventricular arrhythmias or mortality in patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Habibović, Mirela; Pedersen, Susanne S.; van den Broek, Krista C

    2013-01-01

    A subgroup of patients with an implantable cardioverter defibrillator (ICD) experiences anxiety after device implantation. The purpose of the present study was to evaluate whether anxiety is predictive of ventricular arrhythmias and all-cause mortality 1 year post ICD implantation....

  19. Ventricular Tachyarrhythmias and Mortality in Patients With an Implantable Cardioverter Defibrillator

    DEFF Research Database (Denmark)

    Mastenbroek, Mirjam H; Versteeg, Henneke; Jordaens, Luc

    2014-01-01

    Objective We examined whether depression is independently associated with implantable cardioverter defibrillator (ICD) therapy for ventricular tachyarrhythmias and mortality. Methods A cohort of 430 consecutive patients with a first-time ICD (79% men; mean [standard deviation] age = 57.8 [12.1] y...

  20. Inappropriate shock delivery by implantable cardioverter defibrillator due to electrical interference with washing machine.

    Science.gov (United States)

    Chongtham, Dhanaraj Singh; Bahl, Ajay; Kumar, Rohit Manoj; Talwar, K K

    2007-05-31

    We report a patient with hypertrophic cardiomyopathy who received an inappropriate implantable cardioverter defibrillator shock due to electrical interference from a washing machine. This electrical interference was detected as an episode of ventricular fibrillation with delivery of shock without warning symptoms.

  1. "Real life" longevity of implantable cardioverter-defibrillator devices.

    Science.gov (United States)

    Manolis, Antonis S; Maounis, Themistoklis; Koulouris, Spyridon; Vassilikos, Vassilios

    2017-09-01

    Manufacturers of implantable cardioverter-defibrillators (ICDs) promise a 5- to 9-year projected longevity; however, real-life data indicate otherwise. The aim of the present study was to assess ICD longevity among 685 consecutive patients over the last 20 years. Real-life longevity of ICDs may differ from that stated by the manufacturers. The study included 601 men and 84 women (mean age, 63.1 ± 13.3 years). The underlying disease was coronary (n = 396) or valvular (n = 15) disease, cardiomyopathy (n = 220), or electrical disease (n = 54). The mean ejection fraction was 35%. Devices were implanted for secondary (n = 562) or primary (n = 123) prevention. Single- (n = 292) or dual-chamber (n = 269) or cardiac resynchronization therapy (CRT) devices (n = 124) were implanted in the abdomen (n = 17) or chest (n = 668). Over 20 years, ICD pulse generator replacements were performed in 238 patients (209 men; age 63.7 ± 13.9 years; ejection fraction, 37.7% ± 14.0%) who had an ICD for secondary (n = 210) or primary (n = 28) prevention. The mean ICD longevity was 58.3 ± 18.7 months. In 20 (8.4%) patients, devices exhibited premature battery depletion within 36 months. Most (94%) patients had none, minor, or modest use of ICD therapy. Longevity was longest for single-chamber devices and shortest for CRT devices. Latest-generation devices replaced over the second decade lasted longer compared with devices replaced during the first decade. When analyzed by manufacturer, Medtronic devices appeared to have longer longevity by 13 to 18 months. ICDs continue to have limited longevity of 4.9 ± 1.6 years, and 8% demonstrate premature battery depletion by 3 years. CRT devices have the shortest longevity (mean, 3.8 years) by 13 to 17 months, compared with other ICD devices. These findings have important implications, particularly in view of the high expense involved with this type of electrical

  2. “Atrial torsades de pointes” Induced by Low-Energy Shock From Implantable-Cardioverter Defibrillator

    Directory of Open Access Journals (Sweden)

    Ilknur Can, MD

    2013-09-01

    Full Text Available A 58 year-old-patient developed an episode of polymorphic atrial tachycardia which looked like "atrial torsades de pointes" after a 5J shock from implantable cardioverter defibrillator.

  3. Electromagnetic Interference in Patients with Implanted Cardioverter-Defibrillators and Implantable Loop Recorders

    Directory of Open Access Journals (Sweden)

    Marcos de Sousa

    2002-07-01

    Full Text Available Modern life exposes us all to an ever-increasing number of potential sources of electromagnetic interference (EMI and patients with Implantable rhythm devices (IRD like pacemakers, implantable cardioverter defibrillators or implantable loop recorders often ask about the use of microwave ovens, walking through airport metal detectors and the use of cellular phones. Electromagnetic interference occurs when electromagnetic waves emitted by one device impede the normal function of another electronic device. The potential for interaction between implanted pacing systems and cardioverter-defibrillators (electromagnetic interference, EMI has been recognized for years.1,2,3,4. It has been shown that EMI can produce clinically significant effects on patients with implanted pacemakers and ICDs. For these reasons the following text discusses the influence of several EMI generating devices on IRD .

  4. Wearable cardioverter defibrillator: A life vest till the life boat (ICD arrives

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2014-01-01

    Full Text Available It is well established that implantable cardioverter defibrillator (ICD is a life saving device ensuring protection against life threatening ventricular arrhythmias. But there are certain situations like a recent myocardial infarction where the standard guidelines do not recommend the implantation of an ICD while the patient can still be at a risk of demise due to a life threatening ventricular arrhythmia. There could also be a temporary indication for protection while explanting an infected ICD system. The wearable cardioverter defibrillator (WCD is a device which comes to the rescue in such situations. In this brief review, we discuss the historical aspects of the development of a WCD, technical aspects as well as the clinical trial data and real world scenario of its use.

  5. Spiritual well-being may buffer psychological distress in patients with implantable cardioverter defibrillators (ICD)

    OpenAIRE

    Salmoirago-Blotcher, Elena; Crawford, Sybil; Tran, Chau; Goldberg, Robert; Rosenthal, Lawrence; Ockene, Ira

    2012-01-01

    Psychological distress is common in patients with implantable cardioverter defibrillators (ICDs) and has been associated with a worse prognosis. The authors examined whether spiritual wellbeing is associated with reduced psychological distress in patients with ICDs. The Functional Assessment of Chronic Illness Therapy-Spiritual Wellbeing (FACIT-SWB) questionnare and the Hospital Anxiety and Depression Scale (HADS) were used to measure spiritual wellbeing and overall psychological distress. Mu...

  6. Symptomatic heart failure is the most important clinical correlate of impaired quality of life, anxiety, and depression in implantable cardioverter-defibrillator patients

    DEFF Research Database (Denmark)

    Johansen, Jens B; Pedersen, Susanne S.; Spindler, Helle

    2008-01-01

    To identify correlates of impaired quality of life (QOL), anxiety, and depression in patients with an implantable cardioverter-defibrillator (ICD).......To identify correlates of impaired quality of life (QOL), anxiety, and depression in patients with an implantable cardioverter-defibrillator (ICD)....

  7. Beam Profile Disturbances from Implantable Pacemakers or Implantable Cardioverter-Defibrillator Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Gossman, Michael S., E-mail: mgossman@tsrcc.com [Tri-State Regional Cancer Center, Medical Physics Section, Ashland, KY (United States); Comprehensive Heart and Vascular Associates, Heart and Vascular Center, Ashland, KY (United States); Medtronic, Inc., External Research Program, Mounds View, MN (United States); Nagra, Bipinpreet; Graves-Calhoun, Alison; Wilkinson, Jeffrey [Tri-State Regional Cancer Center, Medical Physics Section, Ashland, KY (United States); Comprehensive Heart and Vascular Associates, Heart and Vascular Center, Ashland, KY (United States); Medtronic, Inc., External Research Program, Mounds View, MN (United States)

    2011-01-01

    The medical community is advocating for progressive improvement in the design of implantable cardioverter-defibrillators and implantable pacemakers to accommodate elevations in dose limitation criteria. With advancement already made for magnetic resonance imaging compatibility in some, a greater need is present to inform the radiation oncologist and medical physicist regarding treatment planning beam profile changes when such devices are in the field of a therapeutic radiation beam. Treatment plan modeling was conducted to simulate effects induced by Medtronic, Inc.-manufactured devices on therapeutic radiation beams. As a continuation of grant-supported research, we show that radial and transverse open beam profiles of a medical accelerator were altered when compared with profiles resulting when implantable pacemakers and cardioverter-defibrillators are placed directly in the beam. Results are markedly different between the 2 devices in the axial plane and the sagittal planes. Vast differences are also presented for the therapeutic beams at 6-MV and 18-MV x-ray energies. Maximum changes in percentage depth dose are observed for the implantable cardioverter-defibrillator as 9.3% at 6 MV and 10.1% at 18 MV, with worst distance to agreement of isodose lines at 2.3 cm and 1.3 cm, respectively. For the implantable pacemaker, the maximum changes in percentage depth dose were observed as 10.7% at 6 MV and 6.9% at 18 MV, with worst distance to agreement of isodose lines at 2.5 cm and 1.9 cm, respectively. No differences were discernible for the defibrillation leads and the pacing lead.

  8. The use of guideline recommended beta-blocker therapy in primary prevention implantable cardioverter defibrillator patients

    DEFF Research Database (Denmark)

    Ruwald, Anne Christine; Gislason, Gunnar Hilmar; Vinther, Michael

    2017-01-01

    Aims: We aimed to examine the use of guideline recommended beta-blocker therapy prior to and after primary prevention implantable cardioverter defibrillator (ICD) implantation in a 'real-life' setting. Methods and results: From the Danish Pacemaker and ICD Registry we identified all 1st-time prim......Aims: We aimed to examine the use of guideline recommended beta-blocker therapy prior to and after primary prevention implantable cardioverter defibrillator (ICD) implantation in a 'real-life' setting. Methods and results: From the Danish Pacemaker and ICD Registry we identified all 1st......-time primary prevention ICD and cardiac resynchronization therapy defibrillator (CRT-D) implantations in Denmark from 2007-12 (n = 2935). Use of beta-blocker, type and dose was acquired through the Danish Prescription Registry. According to guideline recommendations, we defined target daily doses as ≥50 mg...... carvedilol and ≥200 mg metoprolol. Prior to implantation 2427 of 2935 (83%) patients received beta-blocker therapy, with 2166 patients (89%) having initiated treatment 3 months or more prior to implantation. The majority of patients was prescribed carvedilol (52%) or metoprolol (41%). Patients on carvedilol...

  9. The oral cavity is not a primary source for implantable pacemaker or cardioverter defibrillator infections

    Science.gov (United States)

    2013-01-01

    Background To test the hypothesis that the oral cavity is a potential source for implantable pacemaker and cardioverter defibrillators infections, the bacterial diversity on explanted rhythm heart management devices was investigated and compared to the oral microbiome. Methods A metagenomic approach was used to analyze the bacterial diversity on the surfaces of non-infected and infected pacemakers. The DNA from surfaces swaps of 24 non-infected and 23 infected pacemaker were isolated and subjected to bacterial-specific DNA amplification, single strand conformation polymorphism- (SSCP) and sequencing analysis. Species-specific primer sets were used to analyze for any correlation between bacterial diversity on pacemakers and in the oral cavity. Results DNA of bacterial origin was detected in 21 cases on infected pacemakers and assigned to the bacterial phylotypes Staphylococcus epidermidis, Propionibacterium acnes, Staphylococcus aureus, Staphylococcus schleiferi and Stapyhlococcus. In 17 cases bacterial DNA was found on pacemakers with no clinical signs of infections. On the basis of the obtained sequence data, the phylotypes Propionibacterium acnes, Staphylococcus and an uncultured bacterium were identified. Propionibacterium acnes and Staphylococcus epidermidis were the only bacteria detected in pacemeaker (n = 25) and oral samples (n = 11). Conclusions The frequency of the coincidental detection of bacteria on infected devices and in the oral cavity is low and the detected bacteria are highly abundant colonizers of non-oral human niches. The transmission of oral bacteria to the lead or device of implantable pacemaker or cardioverter defibrillators is unlikely relevant for the pathogenesis of pacemaker or cardioverter defibrillators infections. PMID:23575037

  10. Venous Obstruction Following Pacemaker or Implantable Cardioverter-Defibrillator Implantation, Mini Review

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Akbarzadeh

    2016-08-01

    Full Text Available Venous obstruction is relatively frequent following permanent pacemaker or implantable cardioverter-defibrillator (ICD implantation. However, most of them are asymptomatic. Although the exact risk factor for this complication is not known, number of leads, heart failure and infection may prone the patient to this complication. The goal standard for detection of vein stenosis is venography; however, ultrasound sonography has an acceptable accuracy. Anticoagulant therapy may be considered for symptomatic patients. For device upgrading, non-functional leads removal, venoplasty and rarely surgical treatment may be indicated.

  11. Electroconvulsive therapy in patients with cardiac pacemakers and implantable cardioverter defibrillators.

    Science.gov (United States)

    Dolenc, Tamara J; Barnes, Roxann D; Hayes, David L; Rasmussen, Keith G

    2004-09-01

    Electroconvulsive therapy (ECT) is used to treat major depressive illness, especially in elderly and medically frail patients. Not uncommonly, these patients have cardiac pacemakers or implantable cardioverter defibrillators (ICDs). Only a few case reports in the literature describe the use of ECT in such patients. Herein we review our ECT experience treating 26 pacemaker patients and 3 ICD patients. All patients obtained significant antidepressant benefits with ETC. Only one serious cardiac event occurred, a case of supraventricular tachycardia (SVT) requiring a stay on the cardiac intensive care unit. The SVT resolved and the patient went on to receive further uncomplicated ECT treatments. We conclude from this experience that with proper pre-ECT cardiac and pacemaker/defibrillator assessment, ECT can be safely and effectively administered to patients with an implanted cardiac device.

  12. Intensity of primary emotions in patients after implantation of an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Stoier, Louise; Pedersen, Preben Ulrich; Berg, Selina Kikkenborg

    2013-01-01

    Background: Experienced emotions can affect the outcome of, and adherence to a cardiac rehabilitation program, and patients coping with an illness. With more awareness of the expressed emotions, health professionals might be better able to understand the reactions of patients and to improve...... the support needed for coping. Living with an Implantable Cardi- overter Defibrillator can lead to anxiety and depression. Focus on the intensity of the primary emotions might be a potential to prevent development of these psychological states. Objectives: The aim of this paper are 1) to describe...... the intensity of primary emotions in patients after implantation of an Implantable Cardioverter Defibrillator and 2) to compare them with both the intensity of primary emotions in patients with a recent Myocardial Infarction and with a healthy population. Method: The intensity of primary emotions in patients...

  13. Tricuspid Valve Dysfunction Following Pacemaker or Cardioverter-Defibrillator Implantation.

    Science.gov (United States)

    Chang, James D; Manning, Warren J; Ebrille, Elisa; Zimetbaum, Peter J

    2017-05-09

    The potential for cardiac implantable electronic device leads to interfere with tricuspid valve (TV) function has gained increasing recognition as having hemodynamic and clinical consequences associated with incremental morbidity and death. The diagnosis and treatment of lead-related (as distinct from functional) tricuspid regurgitation pose unique challenges. Because of pitfalls in routine diagnostic imaging, a high level of clinical suspicion must be maintained to avoid overlooking the possibility that worsening heart failure is a consequence of mechanical interference with TV leaflet mobility or coaptation and is amenable to lead extraction or valve repair or replacement. The future of cardiac implantable electronic devices includes pacing and perhaps defibrillation without a lead traversing the TV. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  14. Dutch outcome in implantable cardioverter-defibrillator therapy (DO-IT) : Registry design and baseline characteristics of a prospective observational cohort study to predict appropriate indication for implantable cardioverter-defibrillator

    NARCIS (Netherlands)

    Van Barreveld, M. (M.); M.G.W. Dijkgraaf (Marcel); Hulleman, M. (M.); L. Boersma (Lucas); P.P.H.M. Delnoy (Peter Paul); M. Meine (Mathias); Tuinenburg, A.E. (A. E.); D.A.M.J. Theuns (Dominic); P. van der Voort (Pepijn); G-J.P. Kimman (Geert-Jan); E. Buskens (Erik); Tijssen, J.P.G. (J. P.G.); Bruinsma, N. (N.); Verstraelen, T.E. (T. E.); A.H. Zwinderman (Ailko); Van Dessel, P.H.F.M. (P. H.F.M.); A.A.M. Wilde (Arthur)

    2017-01-01

    textabstractBackground Implantable cardioverter-defibrillators (ICDs) are widely used for the prevention of sudden cardiac death. At present, both clinical benefit and cost-effectiveness of ICD therapy in primary prevention patients are topics of discussion, as only a minority of these patients will

  15. A review of economic evaluation models for cardiac resynchronization therapy with implantable cardioverter defibrillators in patients with heart failure

    NARCIS (Netherlands)

    Tomini, F.; van Asselt, A. D.

    OBJECTIVES: Cardiac resynchronization therapy with biventricular pacemaker (CRT-P) is considered an effective treatment for heart failure (HF). Adding implantable cardioverter defibrillators (CRT-D) may further reduce the risk of sudden cardiac death (SCD). However, economic evaluations have shown

  16. A review of economic evaluation models for cardiac resynchronization therapy with implantable cardioverter defibrillators in patients with heart failure

    NARCIS (Netherlands)

    Tomini, F.; van Asselt, A. D.

    2012-01-01

    OBJECTIVES: Cardiac resynchronization therapy with biventricular pacemaker (CRT-P) is considered an effective treatment for heart failure (HF). Adding implantable cardioverter defibrillators (CRT-D) may further reduce the risk of sudden cardiac death (SCD). However, economic evaluations have shown

  17. Patient-reported outcomes in Danish implantable cardioverter defibrillator patients with a Sprint Fidelis lead advisory notification

    DEFF Research Database (Denmark)

    Pedersen, Susanne S; Versteeg, Henneke; Nielsen, Jens Cosedis

    2011-01-01

    Few studies have investigated the association between implantable cardioverter defibrillators (ICDs) and lead advisory notifications and patient-reported outcomes (PROs). We examined (i) whether the mode used to inform patients about a device advisory is associated with PROs, and (ii) whether...... patients with a lead subject to a device advisory report poorer PROs than non-advisory controls....

  18. Shock and patient preimplantation type D personality are associated with poor health status in patients with implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; Tekle, Fetene B; Hoogwegt, Madelein T

    2012-01-01

    Implantable cardioverter-defibrillator (ICD) shock is a critical event to patients associated with well-being after implantation, although other factors may play an equally important role. We compared the association of shock and the patient's preimplantation personality with health status, using...

  19. Emotions and health: findings from a randomized clinical trial on psychoeducational nursing to patients with implantable cardioverter defibrillator.

    Science.gov (United States)

    Kikkenborg Berg, Selina; Støier, Louise; Moons, Philip; Zwisler, Ann-Dorthe; Winkel, Per; Ulrich Pedersen, Preben

    2015-01-01

    Serious illness will inevitably lead to a fundamental emotional reaction. Traditionally, in interventional treatment or rehabilitation trials, the psychological status of patients with implantable cardioverter defibrillators has been evaluated with anxiety and depression as outcome measures. In caring for these patients, the aim of nursing is to help patients manage life with complex heart disease. The early detection and management of negative emotional response might prevent the development of pathological conditions such as depression. The aims of this study were to (a) describe the trajectory of primary emotions over time in patients with implantable cardioverter defibrillators and (b) examine the potential effects of psychoeducational nursing on primary emotions. During the inclusion period (October 2007 to November 2009), 196 patients with implantable cardioverter defibrillator were randomized (1:1) to rehabilitation versus usual care. Rehabilitation consisted of a psychoeducational nursing component and an exercise training component. This article concerns phase 1, psychoeducational nursing, guided by a theory of nursing, Rosemary Rizzo Parses Human Becoming Practice Methodologies. The outcome measure is the Emotions and Health Scale. The scale consists of 8 primary emotions: joy, agreeableness, surprise, fear, sadness, disgust, anger, and anticipation. Mean (SD) age was 58 (13) years, and 79% of the participants were men. Significant improvements were found in primary emotional responses over time (P .05). Primary emotions are affected after implantable cardioverter defibrillator implantation. Improvements over time were found. However, it was not possible to detect any effect of a short-term psychoeducational nursing intervention. Evaluating the primary emotions might be a good way for nurses to monitor patients' psychological outcomes because the instrument is sensitive to changes over a short period. Further development of early psychoeducational nursing

  20. Device orientation of a leadless pacemaker and subcutaneous implantable cardioverter-defibrillator in canine and human subjects and the effect on intrabody communication

    NARCIS (Netherlands)

    Quast, Anne-Floor B. E.; Tjong, Fleur V. Y.; Koop, Brendan E.; Wilde, Arthur A. M.; Knops, Reinoud E.; Burke, Martin C.

    2018-01-01

    The development of communicating modular cardiac rhythm management systems relies on effective intrabody communication between a subcutaneous implantable cardioverter-defibrillator (S-ICD) and a leadless pacemaker (LP), using conducted communication. Communication success is affected by the LP and

  1. Type D personality is associated with increased anxiety and depressive symptoms in patients with an implantable cardioverter defibrillator and their partners

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; van Domburg, Ron T; Theuns, Dominic A M J

    2014-01-01

    We investigated the prevalence of anxiety and depressive symptoms in patients with an implantable cardioverter defibrillator (ICD) and their partners, and the role of personality factors and social support as determinants of distress....

  2. Relation of statin therapy to psychological functioning in patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Theuns, Dominic A M J; Kupper, Nina

    2013-01-01

    Statin therapy is an important secondary prevention measure in cardiovascular disease. However, the side effects associated with statin use could potentially affect patients' quality of life. Little is known about the influence of statin therapy on the well-being and health status of cardiac...... patients, in general, and patients with an implantable cardioverter defibrillator (ICD), in particular. We investigated the association between statin therapy and symptoms of anxiety and depression and patients' health status during the 12 months after implantation, reckoning with statin type and dosage...... of statin type, dosage, and other potential confounders. The associations between statin therapy and depression (p = 0.06) and statin therapy and physical functioning (p = 0.05) were borderline significant, and no association was found with anxiety (p >0.05). In conclusion, statin therapy was associated...

  3. The Subcutaneous Implantable Cardioverter-Defibrillator: A Practical Review and Real-World Use and Application

    Directory of Open Access Journals (Sweden)

    Mark E. Panna Jr, MD, FACC, FHRS

    2016-02-01

    Full Text Available The subcutaneous implantable cardioverter-defibrillator (ICD is a novel technology using a subcutaneous (extrathoracic system for treatment of potential lethal ventricular arrhythmias. It avoids many of the risks of transvenous ICD implantation. It may be considered in patients having an ICD indication who do not have a pacing and/or cardiac resynchronization therapy indication, and who are unlikely to benefit from antitachycardia pacing therapy. We review patient selection, system components, the implantation technique, and screening considerations for subcutaneous ICD implantation. Its uses in specific patient populations, including children, patients with congenital heart disease, hypertrophic cardiomyopathy, or end-stage renal disease, and patients with preexisting pacemakers, are highlighted. Areas of future investigation are reviewed, including potential use with leadless pacing and magnetic resonance imaging.

  4. Trajectories of Patient-Reported Health Status in Patients With an Implantable Cardioverter Defibrillator

    DEFF Research Database (Denmark)

    Mastenbroek, Mirjam H; Denollet, Johan; Versteeg, Henneke

    2015-01-01

    , no use of ACE inhibitors, psychotropic medication, negative affectivity, and type D personality were identified as independent determinants of poorer mental health status. In conclusion, the population with an ICD seems to be heterogeneous in terms of patient-reported physical and mental health status......To date, no study has assessed the course of patient-reported health status in patients with an implantable cardioverter defibrillator (ICD). Studying health status trajectories and their baseline determinants would permit the identification of patients at risk for poor health outcomes after ICD...... implantation. A combined cohort of 1,222 patients with an ICD (79% men; age = 61.4 [11.2] years) completed the 12-Item Short-Form Health Survey at baseline and 2 to 3 months and 12 to 14 months after implantation. Latent class analyses were used to identify trajectories and predictors of health status over...

  5. Interactions between pacing and arrhythmia detection algorithms in the dual chamber implantable cardioverter defibrillator.

    Science.gov (United States)

    Dijkman, B; Wellens, H J

    2001-09-01

    Dual chamber implantable cardioverter defibrillator (ICD) combines the possibility to detect and treat ventricular and atrial arrhythmias with the possibility of modern heart stimulation techniques. Advanced pacing algorithms together with extended arrhythmia detection capabilities can give rise to new types of device-device interactions. Some of the possible interactions are illustrated by four cases documented in four models of dual chamber ICDs. Functioning of new features in dual chamber devices is influenced by the fact that the pacemaker is not a separate device but a part of the ICD system and that both are being used in a patient with arrhythmia. Programming measures are suggested to optimize use of new pacing algorithms while maintaining correct arrhythmia detection.

  6. Attitudes towards implantable cardioverter-defibrillator therapy: a national survey in Danish health-care professionals

    DEFF Research Database (Denmark)

    Johansen, Jens B; Mortensen, Peter T; Videbæk, Regitze

    2011-01-01

    Aims The aim of this study was to examine health-care professionals attitudes towards implantable cardioverter-defibrillator (ICD) therapy and issues discussed with patients. Methods and results Survey of 209 health-care professionals providing specialized treatment and care of ICD patients......-physicians. Physicians were less likely to believe that their personal attitude towards ICD treatment has no influence on how they deal professionally with patients (27.8 vs. 43.6%; P = 0.04). Physicians and non-physicians were equally positive towards ICD therapy as primary prophylaxis in ischaemic cardiomyopathy (87...... discussing ICD treatment with candidate patients. At the same time, physicians are more aware that their attitude towards ICD treatment may influence how they deal professionally with patients compared with non-physicians....

  7. Illness perceptions in patients with heart failure and an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Timmermans, I.; Versteeg, H.; Meine, Mathias M

    2017-01-01

    Background Patients' illness perceptions are associated with psychological wellbeing and can be measured with the Brief Illness Perception Questionnaire (B-IPQ). However, little is known about illness perceptions in patients with heart failure. We examined the dimensional structure, validity...... and clinical and psychological correlates of the B-IPQ in Dutch, French and German patients with heart failure and an implantable cardioverter defibrillator (ICD). Method European heart failure patients (n=585) participating in the REMOTE-CIED study completed a set of questionnaires 1–2weeks post ICD.......69, with the ‘Consequences’ subscale being more internally consistent (α=0.80). Both the B-IPQ and its ‘Consequences’ subscale were significantly correlated with a number of psychological characteristics, but not with clinical characteristics. Multivariable logistic regression analysis indicated that threatening illness...

  8. Patients' perspective on deactivation of the implantable cardioverter-defibrillator near the end of life

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; Chaitsing, Rismy; Szili-Torok, Tamas

    2013-01-01

    (67%) completed the survey. Most patients (68%) were aware that it is possible to turn the ICD off, and 95% believed it is important to inform patients about the possibility. Of the patients completing the survey, 84% indicated a choice for or against deactivation. Psychological morbidity......Recent guidelines have emphasized the importance of discussing the issue of deactivation near the end of life with patients with an implantable cardioverter-defibrillator (ICD). Few studies have examined the patient perspective and patients' wishes. We examined patients' knowledge and wishes...... for information; and the prevalence and correlates of a favorable attitude toward deactivation. Three cohorts of ICD patients (n = 440) extracted from our institutional database were asked to complete a survey that included a vignette about deactivation near the end of life. Of the 440 patients approached, 294...

  9. Relation between emotional distress and heart rate variability in patients with an implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Pedersen, Susanne S.; Theuns, Dominic A M J

    2014-01-01

    We investigated the relationship between Type D personality, depression, and anxiety, and heart rate variability (HRV) in 64 patients with an implantable cardioverter-defibrillator (ICD). HRV was obtained via 24-h Holter monitoring, and 24-h, 30-min daytime rest and 30-min nighttime sleep HRV were...... analyzed. In adjusted analyses, significant associations (standard deviation of normal-to-normal [NN] intervals [SDNN]: p = .043; standard deviation of NN intervals over 5-min periods [SDANN]: p = .010) and a trend (HRV triangular index: p = .09) were found for Type D personality, and trends were found...... = .043). A Benjamini-Hochberg correction for multiple testing led to reduction of the number of significant relationships, but there was still support for lower autonomic control patients with Type D personality and depression. Future research with larger sample sizes is warranted....

  10. Gender disparities in psychological distress and quality of life among patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Brouwers, Corline; van den Broek, Krista C; Denollet, Johan

    2011-01-01

    A subset of patients with an implantable cardioverter defibrillator (ICD) reports psychological distress and poor quality of life (QoL). Gender is one of the factors that has been proposed to explain individual differences in these outcomes. In this viewpoint, we (1) review the evidence for gender...... disparities in psychological distress and QoL in ICD patients by means of a systematic review, and (2) provide recommendations for future research and clinical implications. A systematic search of the literature identified 18 studies with a sample size ≥ 100 that examined gender disparities in anxiety....../depression and QoL in ICD patients (mean prevalence of women = 21%; mean age = 62 years). Our review shows that there is insufficient evidence to conclude that gender per se is a major autonomous predictor for disparities in psychological distress and QoL in ICD patients. Women had a higher prevalence of anxiety...

  11. Magnetic resonance imaging at 1.5-T in patients with implantable cardioverter-defibrillators.

    Science.gov (United States)

    Naehle, Claas P; Strach, Katharina; Thomas, Daniel; Meyer, Carsten; Linhart, Markus; Bitaraf, Sascha; Litt, Harold; Schwab, Jörg Otto; Schild, Hans; Sommer, Torsten

    2009-08-04

    Our aim was to establish and evaluate a strategy for safe performance of magnetic resonance imaging (MRI) at 1.5-T in patients with implantable cardioverter-defibrillators (ICDs). Expanding indications for ICD placement and MRI becoming the imaging modality of choice for many indications has created a growing demand for MRI in ICD patients, which is still considered an absolute contraindication. Non-pacemaker-dependent ICD patients with a clinical need for MRI were included in the study. To minimize radiofrequency-related lead heating, the specific absorption rate was limited to 2 W/kg. ICDs were reprogrammed pre-MRI to avoid competitive pacing and potential pro-arrhythmia: 1) the lower rate limit was programmed as low as reasonably achievable; and 2) arrhythmia detection was programmed on, but therapy delivery was programmed off. Patients were monitored using electrocardiography and pulse oximetry. All ICDs were interrogated before and after the MRI examination and after 3 months, including measurement of pacing capture threshold, lead impedance, battery voltage, and serum troponin I. Eighteen ICD patients underwent a total of 18 MRI examinations at 1.5-T; all examinations were completed safely. All ICDs could be interrogated and reprogrammed normally post-MRI. No significant changes of pacing capture threshold, lead impedance, and serum troponin I were observed. Battery voltage decreased significantly from pre- to post-MRI. In 2 MRI examinations, oversensing of radiofrequency noise as ventricular fibrillation occurred. However, no attempt at therapy delivery was made. MRI of non-pacemaker-dependent ICD patients can be performed with an acceptable risk/benefit ratio under controlled conditions by taking both MRI- and pacemaker-related precautions. (Implantable Cardioverter Defibrillators and Magnetic Resonance Imaging of the Heart at 1.5-Tesla; NCT00356239).

  12. Electrical storm in patients with implantable cardioverter-defibrillators: can it be forecast?

    Science.gov (United States)

    Emkanjoo, Zahra; Alihasani, Narges; Alizadeh, Abolfath; Tayyebi, Mohammad; Bonakdar, Hamid; Barakpour, Hamid; Sadr-Ameli, Mohammad Ali

    2009-01-01

    The aim of this retrospective study was to determine the prevalence and predictors of electrical storm in 227 patients who had received implantable cardioverter-defibrillators (ICDs) and had been monitored for 31.7 +/- 15.6 months. Of these, 174 (77%) were men. The mean age was 55.8 +/- 15.5 years (range, 20-85 yr), and the mean left ventricular ejection fraction (LVEF) was 0.30 +/- 0.14. One hundred forty-six of the patients (64%) had underlying coronary artery disease. Cardioverter-defibrillators were implanted for secondary (80%) and primary (20%) prevention. Of the 227 patients, 117 (52%) experienced events that required ICD therapy. Thirty patients (mean age, 57.26 +/- 14.3 yr) had > or = 3 episodes requiring ICD therapy in a 24-hour period and were considered to have electrical storm. The mean number of events was 12.75 +/- 15 per patient. Arrhythmia-clustering occurred an average of 6.1 +/- 6.7 months after ICD implantation. Clinical variables with the most significant association with electrical storm were low LVEF (P = 0.04; hazard ratio of 0.261, and 95% confidence interval of 0.08-0.86) and higher use of class IA antiarrhythmic drugs (P = 0.018, hazard ratio of 3.84, and 95% confidence interval of 1.47-10.05). Amiodarone treatment and use of beta-blockers were not significant predictors when subjected to multivariate analysis. We conclude that electrical storm is most likely to occur in patients with lower LVEF and that the use of Class IA antiarrhythmic drugs is a risk factor.

  13. How does an implantable cardioverter defibrillator (ICD) affect the lives of patients and their families?

    Science.gov (United States)

    Eckert, Marion; Jones, Tina

    2002-06-01

    This study aimed to identify the lived experience of patients with implantable cardioverter defibrillators (ICD) and their families. The methodology used was interpretative phenomenology. Unstructured interviews were conducted with three family members and three ICD recipients. Using a methodological approach outlined by van Manen, the participants transcribed texts were analysed looking for similar concepts and ideas that developed into themes that explicated the meaning of this phenomena. The themes that emerged were: dependence, which encompassed their perceptions about the life-saving device; the memory of their first defibrillation experience; lifestyle changes, which incorporated modification techniques; lack of control, which highlighted feelings such as fear, anxiety and powerlessness; mind game, which illustrated psychological challenges; and the issue of security, demonstrating how 'being there' and not 'being there' impacted on their everyday lives. The long-term outcomes of living with an ICD are important considerations for all health-care providers. This research highlights the everyday activities of recipients, the lifestyle changes they have made, the emotional significance of the device and the psychological coping strategies that the participants have adopted. The findings of this research will allow health-care professionals to be better prepared to provide education and support for ICD recipients and their families in regards to issues related to insertion of the device during the postinsertion recovery period and for long-term management after hospital discharge.

  14. General anaesthesia for insertion of an automated implantable cardioverter defibrillator in a child with Brugada and autism

    Directory of Open Access Journals (Sweden)

    Shwetal Goraksha

    2010-01-01

    Full Text Available A 14-year-old autistic boy presented with acute gastroenteritis and hypotension. The electrocardiogram showed a ventricular fibrillation rhythm - he went into cardiorespiratory arrest and was immediately resuscitated. On investigation, the electrocardiogram showed a partial right bundle branch block with a "coved" pattern of ST elevation in leads v 1 -v 3 . A provisional diagnosis of Brugada syndrome was made, for which an automated implantable cardioverter defibrillator (AICD implantation was advised. Although the automated implantable cardioverter defibrillator implantation is usually performed under sedation, because this was an autistic child, he needed general anaesthesia. We performed the procedure uneventfully under general anaesthesia and he was discharged after a short hospital stay.

  15. Psychometric properties of HeartQoL, a core heart disease-specific health-related quality of life questionnaire, in Danish implantable cardioverter defibrillator recipients

    DEFF Research Database (Denmark)

    Zangger, Graziella; Zwisler, Ann-Dorthe; Kikkenborg Berg, Selina

    2018-01-01

    disease-specific health-related quality of life questionnaire, in implantable cardioverter defibrillator recipients. Design This study involved cross-sectional and test-retest study designs. Method Implantable cardioverter defibrillator recipients in the cross-sectional study completed the Heart......QoL, the Short-Form 36 Health Survey, and the Hospital Anxiety and Depression Scale. The HeartQoL structure, construct-related validity (convergent and discriminative) and reliability (internal consistency) were assessed. HeartQoL reproducibility (test-retest) was assessed in an independent sample of implantable...... psychometric attributes of validity and reliability in this implantable cardioverter defibrillator population. This study adds support for the HeartQoL as a core heart-specific health-related quality of life questionnaire in a broad group of patients with heart disease including implantable cardioverter...

  16. "Pseudo" Faraday cage: a solution for telemetry link interaction between a left ventricular assist device and an implantable cardioverter defibrillator.

    Science.gov (United States)

    Jacob, Sony; Cherian, Prasad K; Ghumman, Waqas S; Das, Mithilesh K

    2010-09-01

    Patients implanted with left ventricular assist devices (LVAD) may have implantable cardioverter defibrillators (ICD) implanted for sudden cardiac death prevention. This opens the possibility of device-device communication interactions and thus interferences. We present a case of such interaction that led to ICD communication failure following the activation of an LVAD. In this paper, we describe a practical solution to circumvent the communication interference and review the communication links of ICDs and possible mechanisms of ICD-LVAD interactions.

  17. Effect of defibrillation threshold testing on effectiveness of the subcutaneous implantable cardioverter defibrillator.

    Science.gov (United States)

    Peddareddy, Lakshmi; Merchant, Faisal M; Leon, Angel R; Smith, Paige; Patel, Akshar; El-Chami, Mikhael F

    2018-06-12

    Defibrillation threshold (DFT) testing is recommended with the subcutaneous ICD (SICD). To describe first shock efficacy for appropriate SICD therapies stratified by the presence of implant DFT testing. We reviewed all patients receiving SICDs at our institution and stratified them based on whether implant DFT testing was performed. Appropriate shocks were reviewed to see if ventricular tachycardia/ventricular fibrillation (VT/VF) terminated with a single shock. First shock efficacy was stratified by implant DFT status. 178 patients implanted with SICDs and followed in our center were included in this study. Of these, 135 (76 %) underwent DFT testing (DFT (+) group). In the DFT (+) 80 appropriate shocks were needed to treat 69 episodes of VT/VF. The first shock was effective in 61 out of 69 episodes (88.4 %), whereas multiple shocks were required to terminate VT/VF in the remaining 8 episodes. Among 43 patients without implant DFT testing (DFT (-) group), 20 appropriate shocks to treat 17 episodes of VT/VF occurred in 7 patients. VT/VF was successfully terminated with the first shock in 16 out of 17 episodes (first shock efficacy 94.1 %). There was no significant difference in first shock effectiveness between those with and without implant DFT testing (p = 0.97). A strategy that omits DFT testing at implant did not appear to compromise the effictiveness of the SICD. These data suggest that routine DFT testing at SICD implant might not be necessary. Randomized trials are needed to confirm this finding. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  18. The NO Regular Defibrillation testing In Cardioverter Defibrillator Implantation (NORDIC ICD) trial: concept and design of a randomized, controlled trial of intra-operative defibrillation testing during de novo defibrillator implantation.

    Science.gov (United States)

    Bänsch, Dietmar; Bonnemeier, Hendrik; Brandt, Johan; Bode, Frank; Svendsen, Jesper Hastrup; Felk, Angelika; Hauser, Tino; Wegscheider, Karl

    2015-01-01

    Although defibrillation (DF) testing is still considered a standard procedure during implantable cardioverter-defibrillator (ICD) insertion and has been an essential element of all trials that demonstrated the survival benefit of ICD therapy, there are no large randomized clinical trials demonstrating that DF testing improves clinical outcome and if the outcome would remain the same by omitting DF testing. Between February 2011 and July 2013, we randomly assigned 1077 patients to ICD implantation with (n = 540) or without (n = 537) DF testing. The intra-operative DF testing was standardized across all participating centres. After inducing a fast ventricular tachycardia (VT) with a heart rate ≥240 b.p.m. or ventricular fibrillation (VF) with a low-energy T-wave shock, DF was attempted with an initial 15 J shock. If the shock reversed the VT or VF, DF testing was considered successful and terminated. If unsuccessful, two effective 24 J shocks were administered. If DF was unsuccessful, the system was reconfigured and another DF testing was performed. An ICD shock energy of 40 J had to be programmed in all patients for treatment of spontaneous VT/VF episodes. The primary endpoint was the average efficacy of the first ICD shock for all true VT/VF episodes in each patient during follow-up. The secondary endpoints included the frequency of system revisions, total fluoroscopy, implantation time, procedural serious adverse events, and all-cause, cardiac, and arrhythmic mortality during follow-up. Home Monitoring was used in all patients to continuously monitor the system integrity, device programming and performance. The NO Regular Defibrillation testing In Cardioverter Defibrillator Implantation (NORDIC ICD) trial is one of two large prospective randomized trials assessing the effect of DF testing omission during ICD implantation. NCT01282918. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email

  19. Outcomes with single-coil versus dual-coil implantable cardioverter defibrillators: a meta-analysis.

    Science.gov (United States)

    Sunderland, Nicholas; Kaura, Amit; Murgatroyd, Francis; Dhillon, Para; Scott, Paul A

    2018-03-01

    Dual-coil implantable cardioverter defibrillator (ICD) leads have traditionally been used over single-coil leads due to concerns regarding high defibrillation thresholds (DFT) and consequent poor shock efficacy. However, accumulating evidence suggests that this position may be unfounded and that dual-coil leads may also be associated with higher complication rates during lead extraction. This meta-analysis collates data comparing dual- and single-coil ICD leads. Electronic databases were systematically searched for randomized controlled trials (RCT) and non-randomized studies comparing single-coil and dual-coil leads. The mean differences in DFT and summary estimates of the odds-ratio (OR) for first-shock efficacy and the hazard-ratio (HR) for all-cause mortality were calculated using random effects models. Eighteen studies including a total of 138,124 patients were identified. Dual-coil leads were associated with a lower DFT compared to single coil leads (mean difference -0.83J; 95% confidence interval [CI] -1.39--0.27; P = 0.004). There was no difference in the first-shock success rate with dual-coil compared to single-coil leads (OR 0.74; 95%CI 0.45-1.21; P=0.22). There was a significantly lower risk of all-cause mortality associated with single-coil leads (HR 0.91; 95%CI 0.86-0.95; P dual-coil leads. The mortality benefit with single-coil leads most likely represents patient selection bias. Given the increased risk and complexity of extracting dual-coil leads, centres should strongly consider single-coil ICD leads as the lead of choice for routine new left-sided ICD implants. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

  20. [Guidelines on the management of implantable cardioverter defibrillators at the end of life].

    Science.gov (United States)

    Datino, T; Rexach, L; Vidán, M T; Alonso, A; Gándara, Á; Ruiz-García, J; Fontecha, B; Martínez-Sellés, M

    2014-01-01

    This article is a joint document of the Spanish Society of Geriatrics and Gerontology, the Spanish Society of Palliative Care and the Section of Geriatric Cardiology of the Spanish Society of Cardiology. Its aim is to address the huge gap that exists in Spain with regard to the management of implantable cardioverter defibrillators (ICDs) in the final stages of life. It is increasingly common to find patients carrying these devices that are in the terminal stage of an advanced disease. This occurs in patients with advanced heart disease and subsequent heart failure refractory to treatment but also in a patient with an ICD who develops cancer disease, organ failure or other neurodegenerative diseases with poor short-term prognosis. The vast majority of these patients are over 65, so the paper focuses particularly on the elderly who are in this situation, but the decision-making process is similar in younger patients with ICDs who are in the final phase of their life. Copyright © 2013 SEGG. Published by Elsevier Espana. All rights reserved.

  1. Guidelines on the management of implantable cardioverter defibrillators at the end of life.

    Science.gov (United States)

    Datino, T; Rexach, L; Vidán, M T; Alonso, A; Gándara, Á; Ruiz-García, J; Fontecha, B; Martínez-Sellés, M

    2014-01-01

    This article is a joint document of the Spanish Society of Geriatrics and Gerontology, the Spanish Society of Palliative Care and the Section of Geriatric Cardiology of the Spanish Society of Cardiology. Its aim is to address the huge gap that exists in Spain with regard to the management of implantable cardioverter defibrillators (ICDs) in the final stages of life. It is increasingly common to find patients carrying these devices that are in the terminal stage of an advanced disease. This occurs in patients with advanced heart disease and subsequent heart failure refractory to treatment but also in a patient with an ICD who develops cancer disease, organ failure or other neurodegenerative diseases with poor short-term prognosis. The vast majority of these patients are over 65, so the paper focuses particularly on the elderly who are in this situation, but the decision-making process is similar in younger patients with ICDs who are in the final phase of their life. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  2. Time dependence of risks and benefits in pediatric primary prevention implantable cardioverter-defibrillator therapy.

    Science.gov (United States)

    DeWitt, Elizabeth S; Triedman, John K; Cecchin, Frank; Mah, Doug Y; Abrams, Dominic J; Walsh, Edward P; Gauvreau, Kimberlee; Alexander, Mark E

    2014-12-01

    Implantable cardioverter defibrillators (ICDs) used to prevent sudden cardiac arrest in children not only provide appropriate therapy in 25% of patients but also result in a significant incidence of inappropriate shocks and other device complications. ICDs placed for secondary prevention have higher rates of appropriate therapy than those placed for primary prevention. Pediatric patients with primary prevention ICDs were studied to determine time-dependent incidence of appropriate use and adverse events. A total of 140 patients aged prevention were retrospectively identified. Demographics and times to first appropriate shock; adverse events (including inappropriate shock, lead failure, reintervention, and complication); generator replacement and follow-up were noted. During mean follow-up of 4 years, appropriate shock occurred in 19% patients and first adverse event (excluding death/transplant) occurred in 36%. Risk of death or transplant was ≈1% per year and was not related to receiving appropriate therapy. Conditional survival analysis showed rates of appropriate therapy and adverse events decrease soon after implantation, but adverse events are more frequent than appropriate therapy throughout follow-up. Primary prevention ICDs were associated with appropriate therapy in 19% and adverse event in 36% in this cohort. The incidence of both first appropriate therapy and device-related adverse events decreased during longer periods of follow-up after implantation. This suggests that indications for continued device therapy in pediatric primary prevention ICD patients might be reconsidered after a period of nonuse. © 2014 American Heart Association, Inc.

  3. Evidence of Cognitive Bias in Decision Making Around Implantable-Cardioverter Defibrillators: A Qualitative Framework Analysis.

    Science.gov (United States)

    Matlock, Daniel D; Jones, Jacqueline; Nowels, Carolyn T; Jenkins, Amy; Allen, Larry A; Kutner, Jean S

    2017-11-01

    Studies have demonstrated that patients with primary prevention implantable cardioverter-defibrillators (ICDs) often misunderstand the ICD. Advances in behavioral economics demonstrate that some misunderstandings may be due to cognitive biases. We aimed to explore the influence of cognitive bias on ICD decision making. We used a qualitative framework analysis including 9 cognitive biases: affect heuristic, affective forecasting, anchoring, availability, default effects, halo effects, optimism bias, framing effects, and state dependence. We interviewed 48 patients from 4 settings in Denver. The majority were male (n = 32). Overall median age was 61 years. We found frequent evidence for framing, default, and halo effects; some evidence of optimism bias, affect heuristic, state dependence, anchoring and availability bias; and little or no evidence of affective forecasting. Framing effects were apparent in overestimation of benefits and downplaying or omitting potential harms. We found evidence of cognitive bias in decision making for ICD implantation. The majority of these biases appeared to encourage ICD treatment. Published by Elsevier Inc.

  4. Congenital short QT syndrome and implantable cardioverter defibrillator treatment: inherent risk for inappropriate shock delivery.

    Science.gov (United States)

    Schimpf, Rainer; Wolpert, Christian; Bianchi, Francesca; Giustetto, Carla; Gaita, Florenzo; Bauersfeld, Urs; Borggrefe, Martin

    2003-12-01

    A congenital short QT interval constitutes a new primary electrical abnormality associated with syncope and/or sudden cardiac death. We report on the initial use of implantable cardioverter defibrillator (ICD) therapy in patients with inherited short QT interval and discuss sensing abnormalities and detection issues. In five consecutive patients from two unrelated European families who had structurally normal hearts, excessively shortened QT intervals, and a strong positive family history of sudden cardiac death, ICDs were placed for primary and secondary prevention. Mean QT intervals were 252 +/- 13 ms (QTc 287 +/- 13 ms). Despite normal sensing behavior during intraoperative and postoperative device testing, 3 of 5 patients experienced inappropriate shock therapies for T wave oversensing 30 +/- 26 days after implantation. Programming lower sensitivities and decay delays prevented further inappropriate discharges. The congenital short QT syndrome constitutes a new clinical entity with an increased risk for sudden cardiac death. Currently, ICD treatment is the only therapeutic option. In patients with short QT interval and implanted ICD, increased risk for inappropriate therapy is inherent due to the detection of short-coupled and prominent T waves. Careful testing of ICD function and adaptation of sensing levels and decay delays without sacrificing correct arrhythmia detection are essential.

  5. Interference of neodymium magnets with cardiac pacemakers and implantable cardioverter-defibrillators: an in vitro study.

    Science.gov (United States)

    Ryf, Salome; Wolber, Thomas; Duru, Firat; Luechinger, Roger

    2008-01-01

    Permanent magnets may interfere with the function of cardiac pacemakers and implantable cardioverter-defibrillators (ICDs). Neodymium-iron-boron (NdFeB) magnets have become widely available in recent years and are incorporated in various articles of daily life. We conducted an in-vitro study to evaluate the ability of NdFeB magnets for home and office use to cause interference with cardiac pacemakers and ICDs. The magnetic fields of ten NdFeB magnets of different size and shape were measured at increasing distances beginning from the surface until a field-strength (B-field) value of 0.5 mT was reached. Furthermore, for each magnet the distance was determined at which a sample pacemaker switched from magnet mode to normal mode. Depending on the size and remanence of individual magnets, a B-field value of 0.5 mT was found at distances ranging from 1.5 cm to 30 cm and a value of 1 mT at distances from 1 cm to 22 cm. The pacemaker behavior was influenced at distances from 1 cm to 24 cm. NdFeB magnets for home and office use may cause interference with cardiac pacemakers and ICDs at distances up to 24 centimeters. Patient education and product declarations should include information about the risk associated with these magnets.

  6. Potential interference of small neodymium magnets with cardiac pacemakers and implantable cardioverter-defibrillators.

    Science.gov (United States)

    Wolber, Thomas; Ryf, Salome; Binggeli, Christian; Holzmeister, Johannes; Brunckhorst, Corinna; Luechinger, Roger; Duru, Firat

    2007-01-01

    Magnetic fields may interfere with the function of cardiac pacemakers and implantable cardioverter-defibrillators (ICDs). Neodymium-iron-boron (NdFeB) magnets, which are small in size but produce strong magnetic fields, have become widely available in recent years. Therefore, NdFeB magnets may be associated with an emerging risk of device interference. We conducted a clinical study to evaluate the potential of small NdFeB magnets to interfere with cardiac pacemakers and ICDs. The effect of four NdFeB magnets (two spherical magnets 8 and 10 mm in diameter, a necklace made of 45 spherical magnets, and a magnetic name tag) was tested in forty-one ambulatory patients with a pacemaker and 29 patients with an ICD. The maximum distance at which the magnetic switch of a device was influenced was observed. Magnetic interference was observed in all patients. The maximum distance resulting in device interference was 3 cm. No significant differences were found with respect to device manufacturer and device types. Small NdFeB magnets may cause interference with cardiac pacemakers and ICDs. Patients should be cautioned about the interference risk associated with NdFeB magnets during daily life.

  7. Cardiac e-learning: Development of a web-based implantable cardioverter defibrillator educational system.

    Science.gov (United States)

    Hickey, Kathleen T; Johnson, Mary P; Biviano, Angelo; Aboelela, Sally; Thomas, Tami; Bakken, Suzanne; Garan, Hasan; Zimmerman, John L; Whang, William

    2011-04-01

    The objective of this study was to design a Web-based implantable cardioverter defibrillator (ICD) module that would allow greater access to learning which could occur at an individual's convenience outside the fast-paced clinical environment. A Web-based ICD software educational program was developed to provide general knowledge of the function of the ICD and the interpretation of the stored electrocardiograms. This learning tool could be accessed at any time via the Columbia University Internet server, using a unique, password protected login. A series of basic and advanced ICD terms were presented using actual ICD screenshots and videos that simulated scenarios the practitioner would most commonly encounter in the fast-paced clinical setting. To determine the usefulness of the site and improve the module, practitioners were asked to complete a brief (less than 5 min) online survey at the end of the module. Twenty-six practitioners have logged into our Web site: 20 nurses/nurse practitioners, four cardiac fellows, and two other practitioners. The majority of respondents rated the program as easy to use and useful. The success of this module has led to it becoming part of the training for student nurse practitioners before a clinical electrophysiology rotation, and the module is accessed by our cardiac entry level fellows before a rotation in the intensive care unit or electrophysiology service. Remote electronic arrhythmia learning is a successful example of the melding of technology and education to enhance clinical learning.

  8. Relation between total shock energy and mortality in patients with implantable cardioverter-defibrillator.

    Science.gov (United States)

    Tenma, Taro; Yokoshiki, Hisashi; Mitsuyama, Hirofumi; Watanabe, Masaya; Mizukami, Kazuya; Kamada, Rui; Takahashi, Masayuki; Sasaki, Ryo; Maeno, Motoki; Okamoto, Kaori; Chiba, Yuki; Anzai, Toshihisa

    2018-05-15

    Implantable Cardioverter-Defibrillator (ICD) shocks have been associated with mortality. However, no study has examined the relation between total shock energy and mortality. The aim of this study is to assess the association of total shock energy with mortality, and to determine the patients who are at risk of this association. Data from 316 consecutive patients who underwent initial ICD implantation in our hospital between 2000 and 2011 were retrospectively studied. We collected shock energy for 3 years from the ICD implantation, and determined the relation of shock energy on mortality after adjusting confounding factors. Eighty-seven ICD recipients experienced shock(s) within 3 years from ICD implantation and 43 patients had died during the follow-up. The amount of shock energy was significantly associated with all-cause death [adjusted hazard ratio (HR) 1.26 (per 100 joule increase), p energy accumulation (≥182 joule) was lower (p energy accumulation (energy accumulation and all-cause death was remarkable in the patients with low left ventricular ejection fraction (LVEF ≤40%) or atrial fibrillation (AF). Increase of shock energy was related to mortality in ICD recipients. This relation was evident in patients with low LVEF or AF. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. The effect of intermittent atrial tachyarrhythmia on heart failure or death in cardiac resynchronization therapy with defibrillator versus implantable cardioverter-defibrillator patients

    DEFF Research Database (Denmark)

    Ruwald, Anne-Christine; Pietrasik, Grzegorz; Goldenberg, Ilan

    2014-01-01

    OBJECTIVES: This study aimed to investigate the effect of both history of intermittent atrial tachyarrhythmias (IAT) and in-trial IAT on the risk of heart failure (HF) or death comparing cardiac resynchronization therapy with defibrillator (CRT-D) to implantable cardioverter-defibrillator (ICD......) treatment in mildly symptomatic HF patients with left bundle branch block (LBBB). BACKGROUND: Limited data exist regarding the benefit of CRT-D in patients with IAT. METHODS: The benefit of CRT-D in reducing the risk of HF/death was evaluated using multivariate Cox models incorporating the presence of......-D versus ICD on the risk of HF/death was not significantly different between LBBB patients with or without history of IAT (HR: 0.50, p = 0.028, and HR: 0.46, p

  10. A patient with severely reduced LV function and electrical storm saved by wearable cardioverter-defibrillator: a case report.

    Science.gov (United States)

    Strauss, Margit; Kouraki, Kleopatra; Skarlos, Alexandros; Zahn, Ralf; Kleemann, Thomas

    2013-06-01

    The wearable cardioverter-defibrillator (WCD) is indicated in patients who are considered to be at temporarily high risk for sudden cardiac death (SCD), when an implantable defibrillator is not yet clearly indicated. We report the case of a 41-year-old patient with a newly diagnosed severely reduced left ventricular (LV) function for suspected myocarditis and repeated nonsustained ventricular tachycardia (VT). This patient was supplied with a WCD who came back to the hospital 4 weeks after discharge with an electrical storm and adequate discharge of the WCD. After application of amiodarone, no further arrhythmias were detected during intrahospital course. For further risk stratification, we performed a magnetic field imaging (MFI), that was reported to be useful in risk assessment of SCD in patients with ischemic cardiomyopathy. This measurement showed a normal result, but we decided to give an implantable cardioverter-defibrillator (ICD) to the patient. During a follow-up of 1 year, no further arrhythmias occurred. With this case, we report the efficacy of a WCD, which is a novel tool in patients at temporarily high risk of SCD and we report a novel method of risk stratification in patients with a high risk of SCD.

  11. Electromagnetic interference from welding and motors on implantable cardioverter-defibrillators as tested in the electrically hostile work site.

    Science.gov (United States)

    Fetter, J G; Benditt, D G; Stanton, M S

    1996-08-01

    This study was designed to determine the susceptibility of an implanted cardioverter-defibrillator to electromagnetic interference in an electrically hostile work site environment, with the ultimate goal of allowing the patient to return to work. Normal operation of an implanted cardioverter-defibrillator depends on reliable sensing of the heart's electrical activity. Consequently, there is concern that external electromagnetic interference from external sources in the work place, especially welding equipment or motor-generator systems, may be sensed and produce inappropriate shocks or abnormal reed switch operation, temporarily suspending detection of ventricular tachycardia or ventricular fibrillation. The effects of electromagnetic interference on the operation of one type of implantable cardioverter-defibrillator (Medtronic models 7217 and 7219) was measured by using internal event counter monitoring in 10 patients operating arc welders at up to 900 A or working near 200-hp motors and 1 patient close to a locomotive starter drawing up to 400 A. The electromagnetic interference produced two sources of potential interference on the sensing circuit or reed switch operation, respectively: 1) electrical fields with measured frequencies up to 50 MHz produced by the high currents during welding electrode activation, and 2) magnetic fields produced by the current in the welding electrode and cable. The defibrillator sensitivity was programmed to the highest (most sensitive) value: 0.15 mV (model 7219) or 0.3 mV (model 7217). The ventricular tachycardia and ventricular fibrillation therapies were temporarily turned off but the detection circuits left on. None of the implanted defibrillators tested were affected by oversensing of the electric field as verified by telemetry from the detection circuits. The magnetic field from 225-A welding current produced a flux density of 1.2 G; this density was not adequate to close the reed switch, which requires approximately 10 G

  12. Risk of pacemaker or implantable cardioverter defibrillator after radiotherapy for early-stage breast cancer in Denmark, 1982-2005

    DEFF Research Database (Denmark)

    Rehammar, Jens Christian; Johansen, Jens Brock; Jensen, Maj-Britt

    2017-01-01

    BACKGROUND AND PURPOSE: To examine the risk of cardiac conduction abnormalities or severe ventricular arrhythmias requiring implantation of a cardiac implantable electronic device (CIED), either a pacemaker or an implantable cardioverter-defibrillator, subsequent to breast cancer (BC) radiotherapy...... (RT). MATERIAL AND METHODS: All women treated for early-stage BC in Denmark from 1982 to 2005 were identified from the Danish Breast Cancer Cooperative Group. By record linkage to the Danish Pacemaker and ICD Registry information was retrieved on CIED implants subsequent to RT. Standardized incidence...

  13. Cognitive behavioral therapy (CBT in a Patient with Implantable Cardioverter Defibrillator (ICD and Posttraumatic stress disorder(PTSD.

    Directory of Open Access Journals (Sweden)

    Sahar Ansari

    2014-09-01

    Full Text Available The implantable cardioverter defibrillator (ICD has currently become the standard treatment for preventing sudden cardiac death. There are some psychological consequences in patients with ICD such as posttraumatic stress disorder (PTSD after the shocks induced by ICD. This report aimed to present the case of a 54-year-old man with ICD who had developed PTSD; his PTSD was treated, using cognitive-behavioral psychotherapy consisting of relaxation, mindfulness and problem solving techniques. In patients with ICD who are experiencing PTSD using cognitive behavioral interventions may be helpful to reduce their psychological sufferings.

  14. Comparison of clinical benefits and outcome in patients with programmable and nonprogrammable implantable cardioverter defibrillators.

    Science.gov (United States)

    Mehta, D; Saksena, S; Krol, R B; Makhija, V

    1992-09-01

    Technological advances in implantable cardioverter defibrillators (ICDs) have provided a variety of programmable parameters and antitachycardia therapies whose utility and impact on clinical outcome is presently unknown. ICDs have capabilities for cardioversion defibrillation alone (first generation ICDs), or in conjunction with demand ventricular pacing (second generation ICDs), or with demand pacing and antitachycardia pacing (third generation ICDs). We examined the pattern of antitachycardia therapy use and long-term survival in 110 patients with sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Group I included 62 patients with nonprogrammable first generation ICDs that delivered committed shock therapy after ventricular tachyarrhythmia detection based on electrogram rate and/or morphology was satisfied. Group II included 48 patients with multiprogrammable ICDs (including second and third generation ICDs) that had programmable tachyarrhythmia detection based on rate and tachycardia confirmation prior to delivery of electrical treatment with either programmable shocks and/or, as in the third generation ICDs, antitachycardia pacing. Incidence and patterns of antitachycardia therapy use and long-term survival were compared in the two groups. The incidence of appropriate shocks in patients who completed 1 year of follow-up was significantly greater in group I (30 of 43 patients = 70% vs 11 of 26 patients = 42%; P less than 0.05). In the total follow-up period, a significantly larger proportion of group I patients as compared to group II patients used the shock therapies (46 of 62 patients = 74% vs 25 of 48 patients = 52%; P less than 0.01), with the majority doing so within the first year of implantation (96% and 92%, respectively). Although the frequency of antitachycardia therapy activation was similar, the number of shocks delivered per patient was lower in group II, particularly in the initial 3 months of follow-up (P = 0.06). No clinical

  15. Management of patients with implantable cardioverter-defibrillators and pacemakers who require radiation therapy.

    Science.gov (United States)

    Brambatti, Michela; Mathew, Rebecca; Strang, Barbara; Dean, Joan; Goyal, Anuja; Hayward, Joseph E; Long, Laurene; DeMeis, Patty; Smoke, Marcia; Connolly, Stuart J; Morillo, Carlos A; Amit, Guy; Capucci, Alessandro; Healey, Jeff S

    2015-10-01

    Radiation therapy (RT) may pose acute and long-term risks for patients with cardiac implantable electronic devices (CIEDs), including pacemakers (PMs) and implantable cardioverter-defibrillators (ICDs). However, the frequency of these problems has not been accurately defined. The purpose of this study was to determine the prevalence of CIEDs among patients requiring RT and report the common CIED-related problems when patients are managed according to a standard clinical care path. In a single tertiary-care center, we prospectively screened all patients requiring RT and identified patients with ICDs or PMs. We collected clinical data about their cancer, RT treatment plan, and CIED. Radiation dose to the device was estimated in all patients, and any device malfunction during RT was documented. Of the 34,706 consecutive patients receiving RT, 261 patients (0.8%, mean age 77.9 ± 9.4 years) had an implantable cardiac device: 54 (20.7%) ICDs and 207 (79.3%) PMs. The site of RT was head and neck (27.4%), chest (30.0%), and abdomen/pelvis (32.6%). Using our care path, 63.2% of patients required continuous cardiac monitoring, 14.6% required device reprogramming, 18.8% required magnet application during RT, and 3.4% required device repositioning to the contralateral side before RT. Four patients (1.5%) had inappropriate device function during RT: 3 experienced hemodynamically tolerated ventricular pacing at the maximum sensor rate, and 1 experienced a device power-on-reset. No patient died or suffered permanent device failure. Nearly 1% of patients receiving RT in this series has a PM or ICD. However, with a systematic policy of risk assessment and patient management, significant device-related complications are rare. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  16. Sustaining cyborgs: sensing and tuning agencies of pacemakers and implantable cardioverter defibrillators.

    Science.gov (United States)

    Oudshoorn, Nelly

    2015-02-01

    Recently there has been a renewed interest in cyborgs, and particularly in new and emerging fusions of humans and technologies related to the development of human enhancement technologies. These studies reflect a trend to follow new and emerging technologies. In this article, I argue that it is important to study 'older' and more familiar cyborgs as well. Studying 'the old' is important because it enables us to recognize hybrids' embodied experiences. This article addresses two of these older hybrids: pacemakers and implantable cardioverter defibrillators inserted in the bodies of people suffering from heart-rhythm disturbances. My concern with hybrid bodies is that internal devices seem to present a complex and neglected case if we wish to understand human agency. Their 'users' seem to be passive because they cannot exert any direct control over the working of their devices. Technologies inside bodies challenge a longstanding tradition of theorizing human-technology relations only in terms of technologies external to the body. Cyborg theory is problematic as well because most studies tend to conceptualize the cyborg merely as a discursive entity and silence the voices of people living as cyborgs. Inspired by feminist research that foregrounds the materiality of the lived and intimate relations between bodies and technologies, I argue that creating these intimate relations requires patients' active involvement in sustaining their hybrid bodies. Based on observations of these monitoring practices in a Dutch hospital and interviews with patients and technicians, the article shows that heart cyborgs are far from passive. On the contrary, their unique experience in sensing the entangled agencies of technologies and their own heart plays a crucial role in sustaining their hybrid bodies.

  17. Influence of radiotherapy on the latest generation of implantable cardioverter-defibrillators

    International Nuclear Information System (INIS)

    Hurkmans, Coen W.; Scheepers, Egon; Springorum, Bob G.F.; Uiterwaal, Hans

    2005-01-01

    Purpose: Radiotherapy can influence the functioning of pacemakers and implantable cardioverter-defibrillators (ICDs). ICDs offer the same functionality as pacemakers, but are also able to deliver a high-voltage shock to the heart if needed. Guidelines for radiotherapy treatment of patients with an implanted rhythm device have been published in 1994 by The American Association of Physicists in Medicine, and are based only on experience with pacemakers. Data on the influence of radiotherapy on ICDs are limited. The objective of our study is to determine the influence of radiotherapy on the latest generation of ICDs. Methods and Materials: Eleven modern ICDs have been irradiated in our department. The irradiation was performed with a 6-MV photon beam. The given dose was fractionated up to a cumulative dose of 120 Gy. Two to 5 days passed between consecutive irradiations. Frequency, output, sensing, telemetry, and shock energy were monitored. Results: Sensing interference by ionizing radiation on all ICDs has been demonstrated. For four ICDs, this would have caused the inappropriate delivery of a shock because of interference. At the end of the irradiation sessions, all devices had reached their point of failure. Complete loss of function was observed for four ICDs at dose levels between 0.5 Gy and 1.5 Gy. Conclusions: The effect of radiation therapy on the newest generation of ICDs varies widely. If tachycardia monitoring and therapy are functional (programmed on) during irradiation, the ICD might inappropriately give antitachycardia therapy, often resulting in a shock. Although most ICDs did not fail below 80 Gy, some devices had already failed at doses below 1.5 Gy. Guidelines are formulated for the treatment of patients with an ICD

  18. Diagnosis and therapy of atrial tachyarrhythmias in the dual chamber implantable cardioverter defibrillator.

    Science.gov (United States)

    Dijkman, B; Wellens, H J

    2000-11-01

    Devices capable of monitoring and treating atrial tachyarrhythmias provide information about the natural history of the arrhythmias and potentially can influence their natural course by electrical therapy early after onset. Types of atrial arrhythmias and efficacy of device therapies were evaluated in 30 patients implanted with the Medtronic model 7250 Jewel AF implantable cardioverter defibrillator (ICD). All patients had structural heart disease and documented sustained ventricular and atrial arrhythmias (27 with atrial fibrillation [AF]) before implant. Twenty patients were taking amiodarone, and three were taking sotalol. During 20+/-10 months of follow-up, 600 atrial arrhythmia recurrences were documented in 50% of patients. AF was diagnosed in 19%, fast polymorphic atrial tachycardia (AT) in 20%, fast monomorphic AT in 57%, and slow AT in 4% of episodes. The two adaptive pacing therapies, burst and ramp, together with the 50-Hz burst, were successful in 57% of detected atrial arrhythmias. Burst and ramp were responsible for 49% and 50-Hz burst for 51% of successfully treated arrhythmias; 33% of the episodes terminated spontaneously. No ventricular proarrhythmia was observed due to atrial pacing therapies. In 30% of episodes, dual chamber pacing was required due to post termination bradycardia. Atrial arrhythmia recurrences in patients with dilated cardiomyopathy were not amenable to pacing therapies. Several aspects of atrial arrhythmia diagnosis, therapy, and documentation that are specific for functioning of the Jewel AF are discussed. Atrial arrhythmias in ICD patients with diseased hearts who are taking Class III antiarrhythmics frequently had longer cycle lengths than AF. Half of these arrhythmias could be terminated with pacing therapies; one third terminated spontaneously.

  19. Importance of the atrial channel for ventricular arrhythmia therapy in the dual chamber implantable cardioverter defibrillator.

    Science.gov (United States)

    Dijkman, B; Wellens, H J

    2000-12-01

    Performance of dual chamber implantable cardioverter defibrillator (ICD) systems has been judged based on functioning of the ventricular tachycardia:supraventricular tachycardia (VT:SVT) discrimination criteria and DDD pacing. The purpose of this study was to evaluate the use of dual chamber diagnostics to improve the electrical and antiarrhythmic therapy of ventricular arrhythmias. Information about atrial and ventricular rhythm in relation to ventricular arrhythmia occurrence and therapy was evaluated in 724 spontaneous arrhythmia episodes detected and treated by three types of dual chamber ICDs in 41 patients with structural heart disease. Device programming was based on clinically documented and induced ventricular arrhythmias. In ambulatory patients, sinus tachycardia preceded ventricular arrhythmias more often than in the hospital during exercise testing. The incidence of these VTs could be reduced by increasing the dose of a beta-blocking agent in only two patients. In five patients in whom sinus tachycardia developed after onset of hemodynamic stable VT, propranolol was more effective than Class III antiarrhythmics combined with another beta-blocking agent with regard to the incidence of VT and pace termination. In all but three cases, atrial arrhythmias were present for a longer time before the onset of ventricular arrhythmias. During atrial arrhythmias, fast ventricular rates before the onset of ventricular rate were observed more often than RR irregularities and short-long RR sequences. Dual chamber diagnostics allowed proper interpretation of detection and therapy outcome in patients with different types of ventricular arrhythmia. The advantages of the dual chamber ICD system go further than avoiding the shortcomings of the single chamber system. Information from the atrial chamber allows better device programming and individualization of drug therapy for ventricular arrhythmia.

  20. Optimizing implantable cardioverter-defibrillator treatment of rapid ventricular tachycardia: antitachycardia pacing therapy during charging.

    Science.gov (United States)

    Schoels, Wolfgang; Steinhaus, David; Johnson, W Ben; O'hara, Gilles; Schwab, Joerg O; Jenniskens, Inge; Degroot, Paul J; Tang, Feng; Helmling, Erhard

    2007-07-01

    Previous studies in implantable cardioverter-defibrillator (ICD) patients demonstrated the efficacy and safety of antitachycardia pacing (ATP) for rapid ventricular tachycardias (VT). To prevent shock delay in case of ATP failure, a new feature (ATP during charging) was developed to deliver ATP for rapid VT while charging for shock. The purpose of this study was to determine the efficacy and safety of this new feature. In a prospective, nonrandomized trial, patients with standard ICD indication received an EnTrust ICD. VT and ventricular fibrillation (VF) episodes were reviewed for appropriate detection, ATP success, rhythm acceleration, and related symptoms. In 421 implanted patients, 116 VF episodes occurred in 37 patients. Eighty-four (72%) episodes received ATP during or before charging. ATP prevented a shock in 58 (69%) of 84 episodes in 15 patients. ATP stopped significantly more monomorphic (77%) than polymorphic VTs (44%, P = .05). Five (6%) episodes accelerated after ATP but were terminated by the backup shock(s). No symptoms were related to ATP during charging. In four patients, 38 charges were saved by delivering ATP before charging. Of 98 induced VF episodes, 28% were successfully terminated by ATP versus 69% for spontaneous episodes (P <.01). Most VTs detected in the VF zone can be painlessly terminated by ATP delivered during charging, with a low risk of acceleration or symptoms. ATP before charging allows delivery of two ATP attempts before shock in the same time that would otherwise be required to deliver only one ATP plus a shock. It also offers potential battery energy savings.

  1. Complications and Mortality of Single Versus Dual Chamber Implantable Cardioverter Defibrillators

    Directory of Open Access Journals (Sweden)

    Ataallah Bagherzadeh

    2006-04-01

    Full Text Available Background: The implantable cardioverter defibrillators (ICDs are increasingly being used as a treatment modality for life threatening tachyarrhythmia. The purpose of this study was to compare the frequency of complications and mortality between single-chamber and dual-chamber ICD implantation in Shahid Rajaie cardiovascular center. Methods and results: Between January 2000 and December 2004, 234 patients received ICD by a percutaneous transvenous approach and were followed for 33 ± 23 months. The cumulative incidence of complications was 9.4% over the follow-up period. There was no significant difference in overall complication rate between single chamber (VR and dual chamber (DR ICD groups in the follow-up period (P= 0.11. The risk of complications did not have any statistically significant difference in secondary versus primary prevention groups (P=0.06. The complications were not associated with the severity of left ventricular systolic dysfunction (P=0.16.The frequency of lead-related complications was higher in dual chamber ICDs in comparison with single chamber ICDs (P=0.02. There was no significant difference in mortality between different sex groups (P=0.37, different indications for ICD implantation (P=0.43 or between VR and DR ICD groups (P= 0.55. Predictors of mortality were NYHA class III or more (P65 years (P=0.011 and LVEF<30% (P<0.001. The mortality in patients with CAD and DCM were significantly higher than those with other structural heart diseases (P=0.001. Conclusions: Close monitoring of patients during the first 2 month after ICD implantation is recommended because the majority of complications occur early after the procedure.

  2. Digoxin Is Associated With Increased Shock Events and Electrical Storms in Patients With Implantable Cardioverter Defibrillators.

    Science.gov (United States)

    Mina, George S; Acharya, Madan; Shepherd, Taylor; Gobrial, George; Tekeste, Michael; Watti, Hussam; Bhandari, Ruchi; Saini, Aditya; Reddy, Pratap; Dominic, Paari

    2018-03-01

    Recently, digoxin use has been found to associate with higher mortality. Yet, potential mechanisms by which digoxin use increases mortality remain unclear. Increased arrhythmogenicity from digoxin use is one possibility. Thus, we aimed to evaluate the relation between digoxin and shock events in patients with implantable cardioverter defibrillators (ICDs). We performed a retrospective chart review of all patients with ICDs and at least 1 device interrogation at our institution between January 1, 2012, and January 1, 2015. We aimed to cover 1 year of interrogation period. Patients with heart failure, atrial fibrillation, or both were included in the analysis. Patients were divided into 2 groups based on digoxin use, defined as use of digoxin for any period of time during ICD interrogation period. Incidence of ICD shock events and electrical storms and hospitalizations were compared between the 2 groups. The study included 202 patients. Of those, 55 patients were on digoxin and 147 were not on digoxin. Patients on digoxin were more likely to receive ICD shocks (odds ratio [OR] = 2.5, 95% confidence interval [95% CI] = 1.01-6.18, P = .04) and have increased risk of electrical storms ( P = .02). Moreover, total hospitalizations were higher in digoxin users ( P = .02). Multivariate logistic regression analysis also showed that digoxin use was an independent predictor of shock events (OR = 4.07, 95% CI = 1.43-11.58, P = .009). Digoxin is associated with increased shock events and electrical storms in patients with ICDs; however, large randomized controlled studies are needed to confirm our findings.

  3. Development and testing of an algorithm to detect implantable cardioverter-defibrillator lead failure.

    Science.gov (United States)

    Gunderson, Bruce D; Gillberg, Jeffrey M; Wood, Mark A; Vijayaraman, Pugazhendhi; Shepard, Richard K; Ellenbogen, Kenneth A

    2006-02-01

    Implantable cardioverter-defibrillator (ICD) lead failures often present as inappropriate shock therapy. An algorithm that can reliably discriminate between ventricular tachyarrhythmias and noise due to lead failure may prevent patient discomfort and anxiety and avoid device-induced proarrhythmia by preventing inappropriate ICD shocks. The goal of this analysis was to test an ICD tachycardia detection algorithm that differentiates noise due to lead failure from ventricular tachyarrhythmias. We tested an algorithm that uses a measure of the ventricular intracardiac electrogram baseline to discriminate the sinus rhythm isoelectric line from the right ventricular coil-can (i.e., far-field) electrogram during oversensing of noise caused by a lead failure. The baseline measure was defined as the product of the sum (mV) and standard deviation (mV) of the voltage samples for a 188-ms window centered on each sensed electrogram. If the minimum baseline measure of the last 12 beats was algorithm to detect lead failures. The minimum baseline measure for the 24 lead failure episodes (0.28 +/- 0.34 mV-mV) was smaller than the 135 ventricular tachycardia (40.8 +/- 43.0 mV-mV, P <.0001) and 55 ventricular fibrillation episodes (19.1 +/- 22.8 mV-mV, P <.05). A minimum baseline <0.35 mV-mV threshold had a sensitivity of 83% (20/24) with a 100% (190/190) specificity. A baseline measure of the far-field electrogram had a high sensitivity and specificity to detect lead failure noise compared with ventricular tachycardia or fibrillation.

  4. Adherence to an Aerobic Exercise Intervention after an Implantable Cardioverter Defibrillator (ICD).

    Science.gov (United States)

    Dougherty, Cynthia M; Luttrell, Matilda N; Burr, Robert L; Kim, Misun; Haskell, William L

    2016-02-01

    Exercise adherence is an important element in achieving important exercise outcomes. The purpose of this study was to describe adherence in a home-based aerobic exercise program following an implantable cardioverter defibrillator (ICD), determine effects of adherence on peakVO2 , and outline reasons for nonadherence. A single-blind randomized control trial of home walking compared to usual care in 160 patients with an ICD for primary or secondary prevention was conducted. This report is on adherence in the exercise arm (N = 84). Home walking exercise consisted of 8 weeks of aerobic conditioning (60 minutes/day, 5 days/week) followed by 16 weeks of aerobic maintenance (150 minutes/week, 30 minutes/session) at 60-80% of heart rate reserve. Adherence was tracked using Polar heart rate (HR) monitors, pedometers, home exercise logs, and telephone follow-up. Adherence was defined as performing at least 80% of prescribed exercise. For aerobic conditioning, there was a mean frequency of 3.81 walks/week, duration of 1,873 minutes walked, and 17.5% of exercise was in the target HR (THR) zone. For aerobic maintenance, there was a mean frequency of 2.4 walks/week, duration of 1,872 minutes/walked, and 8.7% of exercise was in the THR zone. Those who were 80% adherent achieved a 3.4 mL/kg/min (P = 0.03) improvement in peakVO2 over those who were exercise ranged from scheduling issues to viral illness and fatigue. Adherence to aerobic exercise frequency and duration was high with few dropouts, resulting in higher peakVO2 . Exercise monitoring equipment encouraged adherence and conferred a sense of safety to exercise. ©2015 Wiley Periodicals, Inc.

  5. Prognosis after implantation of cardioverter-defibrillators in Korean patients with Brugada syndrome.

    Science.gov (United States)

    Son, Myoung Kyun; Byeon, Kyeongmin; Park, Seung-Jung; Kim, June Soo; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho; Park, Sang Weon; Kim, Young-Hoon; Park, Hyung Wook; Cho, Jeong Gwan; On, Young Keun

    2014-01-01

    Our study aims to analyze prognosis after implantable cardioverter-defibrillator (ICD) implantation in Korean patients with Brugada syndrome (BrS). This was a retrospective study of BrS patients implanted with an ICD at one of four centers in Korea between January 1998 and April 2012. Sixty-nine patients (68 males, 1 female) were implanted with an ICD based on aborted cardiac arrest (n=38, 55%), history of syncope (n=17, 25%), or induced ventricular tachyarrhythmia on electrophysiologic study in asymptomatic patients (n=14, 20%). A family history of sudden cardiac death and a spontaneous type 1 electrocardiography (ECG) were noted in 13 patients (19%) and 44 patients (64%), respectively. During a mean follow-up of 59±46 months, 4.6±5.5 appropriate shocks were delivered in 19 patients (28%). Fourteen patients (20%) experienced 5.2±8.0 inappropriate shocks caused by supraventricular arrhythmia, lead failure, or abnormal sensing. Six patients were admitted for cardiac causes during follow-up, but no cardiac deaths occurred. An episode of aborted cardiac arrest was a significant predictor of appropriate shock, and the composite of cardiac events in the Cox proportional hazard model [hazard ratio (95% confidence interval) was 11.34 (1.31-97.94) and 4.78 (1.41-16.22), respectively]. However, a spontaneous type 1 ECG was not a predictor of cardiac events. Appropriate shock (28%) and inappropriate shock (20%) were noted during a mean follow-up of 59±46 months in Korean BrS patients implanted with an ICD. An episode of aborted cardiac arrest was the most powerful predictor of cardiac events.

  6. Infrequent physician use of implantable cardioverter-defibrillators risks patient safety.

    Science.gov (United States)

    Lyman, Stephen; Sedrakyan, Art; Do, Huong; Razzano, Renee; Mushlin, Alvin I

    2011-10-01

    Implantable cardioverter-defibrillators (ICDs) have diffused rapidly into clinical practice with little evaluation of their real-world effectiveness. To determine the effect of the adoption of ICD on patient safety, particularly with respect to physician volume and early outcomes. Retrospective cohort of all ICD implantations in New York state from 1997 to 2006, with follow-up at 90 days and 1 year. Setting New York state non-federal hospital discharges in which an ICD was implanted during the admission. Patients were followed forward for 1 year for subsequent admissions. Patients New York state residents undergoing ICD implantation. Effects of annual and career ICD implantation volume on 90-day complication, readmission, reprogramming, mortality and revision of the ICD within 1 year. This cohort (N = 38,992) represents a period of rapid adoption and implementation of this new technology, with frequency more than tripling between 1997 and 2006. We identified 6439 (16.5%) post-implantation complications and 1093 (2.8%) deaths within 90 days of implantation. The majority (73.4%) of physicians implanted one or fewer ICDs per year, and 11.0% of all implantations were performed by these very-low-volume operators. Patients treated by very-low-volume operators were more likely to die (RR = 1.8, 95% CI 1.3 to 2.4) or experience cardiac complications (RR = 4.7, 95% CI 3.3 to 6.8) even after the adjustment for case mix compared to operators who frequently performed ICD implantation. These findings suggest a need for safe and effective implementation strategies for new medical technologies, which minimize patient risk due to rapid diffusion among inexperienced providers and assure that the intended benefit can be maximised rapidly.

  7. Low risk of electromagnetic interference between smartphones and contemporary implantable cardioverter defibrillators.

    Science.gov (United States)

    Burri, Haran; Mondouagne Engkolo, Louis Paulin; Dayal, Nicolas; Etemadi, Abdul; Makhlouf, Anne-Marie; Stettler, Carine; Trentaz, Florence

    2016-05-01

    Manufacturers of implantable cardioverter defibrillators (ICDs) recommend that cell phones be maintained at a distance of ∼15 cm from the implanted device in order to avoid risk of dysfunction due to electromagnetic interference (EMI). Data relating to this issue are outdated and do not reflect modern technology. Our aim was to evaluate whether EMI is still an issue with contemporary ICDs and smartphones. Consecutive patients implanted with a wireless-enabled ICD were tested for potential interference with two models of recent 4G smartphones in conditions intended to maximize risk of EMI. A magnet effect (due to the phone speakers) was tested by placing the smartphones in the standby mode directly over the ICD generator. The presence of EMI artefacts on the real-time electrograms was evaluated by placing the smartphones in the standby, dialling, and operating modes directly over the generator casing and over the parasternal region in the vicinity of the ventricular lead. A total of 63 patients equipped with 29 different models of single, dual, or biventricular ICDs from five major manufacturers were included. None of the patients showed any evidence of interference with the smartphones during any of the 882 tests. The risk of EMI between modern smartphones and contemporary ICDs is low. This is probably due to the filters incorporated in the ICDs and low emission by the phones, as well as the small size of the magnets in the smartphones tested. NCT02330900 (http://www.clinicaltrials.gov). Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  8. Implantable cardioverter-defibrillator explantation for overdiagnosed or overtreated congenital long QT syndrome.

    Science.gov (United States)

    Gaba, Prakriti; Bos, J Martijn; Cannon, Bryan C; Cha, Yong-Mei; Friedman, Paul A; Asirvatham, Samuel J; Ackerman, Michael J

    2016-04-01

    Primary treatment of long QT syndrome (LQTS) currently consists of beta-blocker therapy, although an implantable cardioverter-defibrillator (ICD) is considered for high-risk patients. However, both overdiagnosis and overtreatment must be avoided because their sequelae can be significant. The purpose of this study was to evaluate the prevalence and details of ICD explants in a cohort of patients from a tertiary genetic heart rhythm clinic for a previously rendered diagnosis of LQTS. Overall, 1227 consecutive patients were included in the study. All patients had been referred to the Mayo Clinic for evaluation of possible LQTS and subsequently were either diagnosed with LQTS or dismissed as normal. Further stratification of patients was conducted to assess how many patients had an ICD and how many had a subsequent ICD explant. In total, 170 patients (14%) had an ICD, including 157 of 670 patients (23%) with confirmed LQTS and 13 of 557 patients (2%) who did not have LQTS. Among these, 12 of 1227 (1%) had the ICD removed: 7 of 157 LQTS patients (4.5%) compared to 5 of 14 non-LQTS patients (36%). Before explant, 5 of 12 patients (42%) experienced inappropriate shocks, ranging from 2 to as many as 54 shocks. In addition, 4 had a device-related infection, and 9 had device malfunction (including lead dysfunction or fracture). None of these patients had a breakthrough cardiac event since removal of their ICD during 5.5 ± 3.5 years of follow-up. Implications of overdiagnosis and overtreatment are profound because unnecessary ICD placement can be associated with infection, malfunction, inappropriate shocks, and subsequent anxiety. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  9. Outcomes after asystole events occurring during wearable defibrillator-cardioverter use.

    Science.gov (United States)

    Liang, Jackson J; Bianco, Nicole R; Muser, Daniele; Enriquez, Andres; Santangeli, Pasquale; D'Souza, Benjamin A

    2018-04-26

    To examine whether wearable cardioverter defibrillator (WCD) alarms for asystole improve patient outcomes and survival. All asystole episodes recorded by the WCD in 2013 were retrospectively analyzed from a database of device and medical record documentation and customer call reports. Events were classified as asystole episodes if initial presenting arrhythmia was asystole (< 10 beats/minor ≥ 5 s pause). Survival was defined as recovery at the scene or arrival to a medical facility alive, or not requiring immediate medical attention. Episodes occurring in hospitals, nursing homes, or ambulances were considered to be under medical care. Serious asystole episodes were defined as resulting in unconsciousness, hospital transfer, or death. Of the total 51933 patients having worn the WCD in 2013, there were 257 patients (0.5%) who had asystole episodes and comprised the study cohort. Among the 257 patients (74% male, median age 69 years), there were 264 asystole episodes. Overall patient survival was 42%. Most asystoles were considered "serious" ( n = 201 in 201 patients, 76%), with a 26% survival rate. All 56 patients with "non-serious" asystole episodes survived. Being under medical care was associated with worse survival of serious asystoles. Among acute survivors, 20% later died during WCD use (a median 4 days post asystole episode). Of the 86 living patients at the end of WCD use period, 48 (56%) received ICD/pacemaker and 17 (20%) improved their condition. Survival rates after asystole in patients with WCD are higher than historically reported survival rates. Those under medical care at time of asystole exhibited lower survival.

  10. Feedback to providers improves evidence-based implantable cardioverter-defibrillator programming and reduces shocks.

    Science.gov (United States)

    Silver, Marc T; Sterns, Laurence D; Piccini, Jonathan P; Joung, Boyoung; Ching, Chi-Keong; Pickett, Robert A; Rabinovich, Rafael; Liu, Shufeng; Peterson, Brett J; Lexcen, Daniel R

    2015-03-01

    Implantable cardioverter-defibrillator (ICD) shocks are associated with increased anxiety, health care utilization, and potentially mortality. The purpose of the Shock-Less Study was to determine if providing feedback reports to physicians on their adherence to evidence-based shock reduction programming could improve their programming behavior and reduce shocks. Shock-Less enrolled primary prevention (PP) and secondary prevention (SP) ICD patients between 2009 and 2012 at 118 study centers worldwide and followed patients longitudinally after their ICD implant. Center-specific therapy programming reports (TPRs) were delivered to each center 9 to 12 months after their first enrollment. The reports detailed adherence to evidence-based programming targets: number of intervals to detect ventricular fibrillation (VF NID), longest treatment interval (LTI), supraventricular tachycardia (SVT) discriminators (Wavelet, PR Logic), SVT limit, Lead Integrity Alert (LIA), and antitachycardia pacing (ATP). Clinicians programmed ICDs at their discretion. The primary outcome measure was the change in utilization of evidence-based shock reduction programming before (phase I, n = 2694 patients) and after initiation of the TPR (phase II, n = 1438 patients). Patients implanted after feedback reports (phase II) were up to 20% more likely to have their ICDs programmed in line with evidence-based shock reduction programming (eg, VF NID in PP patients 30/40 in 33.5% vs 18.6%, P programming feedback reports improves adherence to evidence-based shock reduction programming and is associated with lower risk of ICD shocks. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  11. Extended charge banking model of dual path shocks for implantable cardioverter defibrillators.

    Science.gov (United States)

    Dosdall, Derek J; Sweeney, James D

    2008-08-01

    Single path defibrillation shock methods have been improved through the use of the Charge Banking Model of defibrillation, which predicts the response of the heart to shocks as a simple resistor-capacitor (RC) circuit. While dual path defibrillation configurations have significantly reduced defibrillation thresholds, improvements to dual path defibrillation techniques have been limited to experimental observations without a practical model to aid in improving dual path defibrillation techniques. The Charge Banking Model has been extended into a new Extended Charge Banking Model of defibrillation that represents small sections of the heart as separate RC circuits, uses a weighting factor based on published defibrillation shock field gradient measures, and implements a critical mass criteria to predict the relative efficacy of single and dual path defibrillation shocks. The new model reproduced the results from several published experimental protocols that demonstrated the relative efficacy of dual path defibrillation shocks. The model predicts that time between phases or pulses of dual path defibrillation shock configurations should be minimized to maximize shock efficacy. Through this approach the Extended Charge Banking Model predictions may be used to improve dual path and multi-pulse defibrillation techniques, which have been shown experimentally to lower defibrillation thresholds substantially. The new model may be a useful tool to help in further improving dual path and multiple pulse defibrillation techniques by predicting optimal pulse durations and shock timing parameters.

  12. Beta-blocker therapy is not associated with symptoms of depression and anxiety in patients receiving an implantable cardioverter-defibrillator

    NARCIS (Netherlands)

    M.T. Hoogwegt (Madelein); N. Kupper (Nina); D.A.M.J. Theuns (Dominic); L.J.L.M. Jordaens (Luc); S.S. Pedersen (Susanne)

    2012-01-01

    textabstractBeta-blockers are frequently prescribed to implantable cardioverter-defibrillator (ICD) patients. Beta-blocker therapy has been proposed to induce emotional distress such as depression and anxiety, but a paucity of studies has examined the relationship between beta-blockers and distress.

  13. Comorbidity burden is associated with poor psychological well-being and physical health status in patients with an implantable cardioverter-defibrillator

    NARCIS (Netherlands)

    Hoogwegt, M.T.; Kupper, N.; Jordaens, L.; Pedersen, S.S.; Theuns, D.A.M.J.

    2013-01-01

    Aims Comorbidity burden has been linked to survival in patients with an implantable cardioverter-defibrillator (ICD), but no study has examined the influence on psychological well-being and health status. We examined the relationship between comorbidity burden and anxiety, depression, and health

  14. Comorbidity burden is associated with poor psychological well-being and physical health status in patients with an implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Kupper, Nina; Jordaens, Luc

    2013-01-01

    Comorbidity burden has been linked to survival in patients with an implantable cardioverter-defibrillator (ICD), but no study has examined the influence on psychological well-being and health status. We examined the relationship between comorbidity burden and anxiety, depression, and health status...

  15. Current use of implantable electrical devices in Sweden: data from the Swedish pacemaker and implantable cardioverter-defibrillator registry.

    Science.gov (United States)

    Gadler, Fredrik; Valzania, Cinzia; Linde, Cecilia

    2015-01-01

    The National Swedish Pacemaker and Implantable Cardioverter-Defibrillator (ICD) Registry collects prospective data on all pacemaker and ICD implants in Sweden. We aimed to report the 2012 findings of the Registry concerning electrical devices implantation rates and changes over time, 1 year complications, long-term device longevity and patient survival. Forty-four Swedish implanting centres continuously contribute implantation of pacemakers and ICDs to the Registry by direct data entry on a specific website. Clinical and technical information on 2012 first implants and postoperative complications were analysed and compared with previous years. Patient survival data were obtained from the Swedish population register database. In 2012, the mean pacemaker and ICD first implantation rates were 697 and 136 per million inhabitants, respectively. The number of cardiac resynchronization therapy (CRT) first implantations/million capita was 41 (CRT pacemakers) and 55 (CRT defibrillators), with only a slight increase in CRT-ICD rate compared with 2011. Most device implantations were performed in men. Complication rates for pacemaker and ICD procedures were 5.3 and 10.1% at 1 year, respectively. Device and lead longevity differed among manufacturers. Pacemaker patients were older at the time of first implant and had generally worse survival rate than ICD patients (63 vs. 82% after 5 years). Pacemaker and ICD implantation rates seem to have reached a level phase in Sweden. Implantable cardioverter-defibrillator and CRT implantation rates are very low and do not reflect guideline indications. Gender differences in CRT and ICD implantations are pronounced. Device and patient survival rates are variable, and should be considered when deciding device type. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  16. Clinical predictors and prognostic significance of electrical storm in patients with implantable cardioverter defibrillators.

    Science.gov (United States)

    Brigadeau, François; Kouakam, Claude; Klug, Didier; Marquié, Christelle; Duhamel, Alain; Mizon-Gérard, Frédérique; Lacroix, Dominique; Kacet, Salem

    2006-03-01

    Insufficient data exists regarding predictors of electrical storms (ES) and clinical outcome in patients treated with an implantable cardioverter defibrillator (ICD). The purpose of this study was to delineate a subgroup of patients likely to experience ES and to determine the impact of ES on mortality in ICD recipients. Baseline characteristics of 307 ICD-treated patients were retrospectively analysed. ES was defined as two or more ventricular tachyarrhythmias within 24 h leading to an immediate electrical therapy (antitachycardia pacing and/or shock), separated by a period of sinus rhythm. Clinical characteristics and survival of 123 patients experiencing a total of 294 episodes of ES (median 2 ES/patient, range 1-9), were compared with those of 184 ES-free patients during a median follow-up of 826 days (inter-quartile 1141 days). Median actuarial duration for the first ES occurrence after ICD implant was 1417 days [95% confidence interval (CI) 1061-2363] with a median follow-up of 816 days (7-4642 days) in ES-free patients. Univariate analysis identified older age, depressed left ventricular ejection fraction (LVEF), ventricular tachycardia (VT) as index arrhythmia, chronic renal failure and absence of lipid-lowering drugs as variables significantly associated with an increased risk of ES. Multivariable Cox analysis confirmed an independent predictive value for chronic renal failure [hazard ratio (HR) 1.54, 95% CI 0.95-2.51, P=0.052], VT (HR 2.20, 95% CI 1.44-3.37, P=0.0003), and LVEF (HR 0.98, 95% CI 0.97-0.99, P=0.027). In contrast, diabetics (HR 0.49, 95% CI 0.27-0.90, P=0.022) were less affected by ES. There was no difference in survival between both groups. ES is frequent but does not increase mortality in ICD's recipients. Patients with severe systolic dysfunction, chronic renal failure and VT as initial arrhythmia are likely to experience ES. Diabetics are less affected by ES.

  17. Psychological and clinical problems in young adults with implantable cardioverter-defibrillators.

    Science.gov (United States)

    Wójcicka, Mariola; Lewandowski, Michał; Smolis-Bak, Edyta; Szwed, Hanna

    2008-10-01

    Implantable cardioverter-defibrillators (ICD) are the most effective treatment in patients with the risk of sudden cardiac death. ICD improves patients' safety but is also the source of numerous inconveniences. Especially young people consider such ICD-related inconveniences as most unwelcome. To assess the quality of life and main psychological problems encountered in young adults with an ICD. We studied 45 subjects aged 14-29 years (mean 21.2+/-4.3). ICDs were used in primary prevention in 22 patients, and in secondary prevention in 23 patients. Time elapsed from implantation ranged from 5 months to 11 years (4.3+/-2.7 years). Since the problems affecting this group were rather specific, the patients' quality of life was assessed with a special questionnaire addressing important issues and problems associated with living with an ICD. ICD discharges were observed in 67.4% of patients (primary prevention - 45.5%, secondary prevention - 82.6%), multiple shocks in 47.2%, and phantom shocks in 21.4%. Anxiety associated with an ICD discharge was reported by 84.4% of patients. In order to prevent ICD discharges, 53.3% of patients decreased their activity. Problems with memory were observed in 42.2% of patients, with concentration in 47.6%, and with sleep in 42.2%. Almost half of those over 18 years of age were active drivers. None of the subjects experienced an ICD discharge during sexual intercourse. None of the men reported any sexual problems, while seven (41.2%) women did. Almost a quarter of the patients claimed to have had complications after the implantation. Young adult patients generally were compliant to have their ICD checked and accepted their limitations and disease. Fewer people assessed their health status as bad. Some patients in the group studied found it extremely difficult to accept their disease and/or ICD and to adapt to the situation. As many as nine patients believed the ICD implantation had been unnecessary, seven did not accept the ICD, three

  18. Impact of programming strategies aimed at reducing nonessential implantable cardioverter defibrillator therapies on mortality: a systematic review and meta-analysis.

    Science.gov (United States)

    Tan, Vern Hsen; Wilton, Stephen B; Kuriachan, Vikas; Sumner, Glen L; Exner, Derek V

    2014-02-01

    Patients who receive implantable cardioverter defibrillator therapies are at higher risk of death versus those who do not. Programmed settings to reduce nonessential implantable cardioverter defibrillator therapies (therapy reduction programming) have been developed but may have adverse effects. This systematic review and meta-analysis assessed the relationship between therapy reduction programming with the risks of death from any cause, implantable cardioverter defibrillator shocks, and syncope. MEDLINE, EMBASE, and clinicaltrials.gov databases were searched to identify relevant studies. Those that followed patients for ≥6 months and reported mortality were included. Six met the inclusion criteria; 4 randomized (Comparison of Empiric to Physician-Tailored Programming of ICDs [EMPIRIC], Multicenter Automatic Defibrillator Implantation Trial-Reduce Inappropriate Therapy [MADIT-RIT], Avoid Delivering Therapies for Non-sustained Arrhythmias in ICD Patients III [ADVANCE III], and Programming Implantable Cardioverter-Defibrillators in Patients with Primary Prevention Indication to Prolong Time to First Shock [PROVIDE]) and 2 prospective studies (Role of Long Detection Window Programming in Patients With Left Ventricular Dysfunction, Non-ischemic Etiology in Primary Prevention Treated with a Biventricular ICD [RELEVANT] and Primary Prevention Parameters Evaluation [PREPARE]). These 6 studies included 7687 (3598 conventional and 4089 therapy reduction programming) patients. Most (77%) participants were men, had a history of ischemic heart disease (56%), and were prescribed β-blockers (84%). Therapy reduction programming was associated with a 30% relative reduction in mortality (95% confidence interval, 16%-41%; Pprogramming (P=0.5). Therapy reduction programming results in a large, significant, and consistent reduction in mortality, with no apparent increase in the risk of syncope.

  19. Risk of pacemaker or implantable cardioverter defibrillator after radiotherapy for early-stage breast cancer in Denmark, 1982-2005

    DEFF Research Database (Denmark)

    Rehammar, Jens Christian; Johansen, Jens Brock; Jensen, Maj-Britt

    2017-01-01

    BACKGROUND AND PURPOSE: To examine the risk of cardiac conduction abnormalities or severe ventricular arrhythmias requiring implantation of a cardiac implantable electronic device (CIED), either a pacemaker or an implantable cardioverter-defibrillator, subsequent to breast cancer (BC) radiotherapy...... (RT). MATERIAL AND METHODS: All women treated for early-stage BC in Denmark from 1982 to 2005 were identified from the Danish Breast Cancer Cooperative Group. By record linkage to the Danish Pacemaker and ICD Registry information was retrieved on CIED implants subsequent to RT. Standardized incidence...... ratios (SIR) of CIED implantation were estimated for women receiving RT and compared to women not receiving RT for BC. Uni- and multivariate Poisson regression models were used to estimate incidence rate ratios (IRR) among irradiated women compared to non-irradiated. RESULTS: Of 44,423 BC patients, 179...

  20. Implantable Cardioverter-Defibrillator Therapy in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy: Predictors of Appropriate Therapy, Outcomes, and Complications.

    Science.gov (United States)

    Orgeron, Gabriela M; James, Cynthia A; Te Riele, Anneline; Tichnell, Crystal; Murray, Brittney; Bhonsale, Aditya; Kamel, Ihab R; Zimmerman, Stephan L; Judge, Daniel P; Crosson, Jane; Tandri, Harikrishna; Calkins, Hugh

    2017-06-06

    Arrhythmogenic right ventricular dysplasia/cardiomyopathy is characterized by ventricular arrhythmias and sudden cardiac death. Once the diagnosis is established, risk stratification to determine whether implantable cardioverter-defibrillator (ICD) placement is warranted is critical. The cohort included 312 patients (163 men, age at presentation 33.6±13.9 years) with definite arrhythmogenic right ventricular dysplasia/cardiomyopathy who received an ICD. Over 8.8±7.33 years, 186 participants (60%) had appropriate ICD therapy and 58 (19%) had an intervention for ventricular fibrillation/flutter. Ventricular tachycardia at presentation (hazard ratio [HR]: 1.86; 95% confidence interval [CI], 1.38-2.49; P right ventricular dysplasia/cardiomyopathy. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  1. Optimism as predictor of patient-reported outcomes in patients with an implantable cardioverter defibrillator (data from the WEBCARE study)

    DEFF Research Database (Denmark)

    Habibović, M; Broers, E; Heumen, D

    2018-01-01

    OBJECTIVE: The implantable cardioverter defibrillator (ICD) is the treatment of choice for prevention of sudden cardiac death. However, a subgroup of ICD patients experiences psychological adjustment problems post implant. To date, positive psychological constructs (e.g. optimism) have been...... understudied in this population. Hence, we examined the association between optimism and anxiety, depression, and health status at 12-months post implant. METHODS: Patients (N=171) enrolled in the WEB-based distress management study for ICD patients were included in the analyses. Optimism and pessimism (LOT......), and Type D personality (DS14) were administered at baseline, while anxiety (GAD-7), depression (PHQ-9), and health status (SF-12) were assessed at 12-months. RESULTS: The mean age was 59.6±10.06 with 81% being male. After controlling for demographic, personality, and clinical variables, baseline optimism...

  2. In vitro assessment of the immunity of implantable cardioverter-defibrillators to magnetic fields of 50/60 Hz

    International Nuclear Information System (INIS)

    Katrib, J; Nadi, M; Kourtiche, D; Schmitt, P; Roth, P; Magne, I; Souques, M

    2013-01-01

    Public concern for the compatibility of electromagnetic (EM) sources with active implantable medical devices (AIMD) has prompted the development of new systems that can perform accurate exposure studies. EM field interference with active cardiac implants (e.g. implantable cardioverter-defibrillators (ICDs)) can be critical. This paper describes a magnetic field (MF) exposure system and the method developed for testing the immunity of ICD to continuous-wave MFs. The MFs were created by Helmholtz coils, housed in a Faraday cage. The coils were able to produce highly uniform MFs up to 4000 µT at 50 Hz and 3900 µT at 60 Hz, within the test space. Four ICDs were tested. No dysfunctions were found in the generated MFs. These results confirm that the tested ICDs were immune to low frequency MFs. (paper)

  3. Thoracoscopic Left Cardiac Sympathetic Denervation for a Patient with Catecholaminergic Polymorphic Ventricular Tachycardia and Recurrent Implantable Cardioverter-Defibrillator Shocks

    Directory of Open Access Journals (Sweden)

    Woo-Sik Yu

    2015-06-01

    Full Text Available A patient presented with loss of consciousness and conversion. During an exercise test, catecholaminergic polymorphic ventricular tachycardia (CPVT resulted in cardiac arrest. He started taking medication (a beta-blocker and flecainide and an implantable cardioverter defibrillator (ICD was inserted, but the ventricular tachycardia did not resolve. Left cardiac sympathetic denervation (LCSD was then performed under general anesthesia, and the patient was discharged on the second postoperative day without complications. One month after the operation, no shock had been administered by the ICD, and an exercise stress test did not induce ventricular tachycardia. Although beta- blockers are the gold standard of therapy in patients with CPVT, thoracoscopic LCSD is safe and can be an effective alternative treatment option for patients with intractable CPVT.

  4. Psychometric analysis of the Patient Health Questionnaire in Danish patients with an implantable cardioverter defibrillator (The DEFIB-WOMEN study)

    DEFF Research Database (Denmark)

    Pedersen, Susanne S; Mathiasen, Kim; Christensen, Karl Bang

    2016-01-01

    OBJECTIVE: To assess the psychometric properties of the Patient Health Questionnaire (PHQ-9), a measure of depressive symptoms, in a large Danish national cohort of patients with heart disease, implanted with an implantable cardioverter defibrillator (ICD), using item response theory. METHODS: A ...... of nine items for the partial credit model and five of nine items for the generalized partial credit model, indicating that respondents have difficulty discriminating between response options. When collapsing response options 2 and 3, the rescored PHQ-9 had a better fit to both models....... Three items did not fit the partial credit model, but the generalized partial credit model could be fitted to the full item set. CONCLUSION: The unidimensionality and reliability of the Danish version of the PHQ-9 were confirmed. However, the associated consequences of the number of response options (3...

  5. Monitoring treatment expectations in patients with an implantable cardioverter-defibrillator using the EXPECT-ICD scale

    DEFF Research Database (Denmark)

    Habibovic, Mirela; Pedersen, Susanne S.; van den Broek, Krista C

    2014-01-01

    AIMS: Patient treatment expectations may affect cardiac outcomes; however, till date, no validated instruments have been developed to monitor treatment expectations in patients with an implantable cardioverter-defibrillator (ICD). This study evaluates the predictive value of the newly developed 10...... with a two-factor model involving both negative (α = 0.84) and positive expectations (α = 0.77) with a score range of 0-20 for each factor. Negative treatment expectations were associated with higher levels of anxiety (β = 0.443; P ...-item EXPECtations Towards ICD therapy (EXPECT-ICD) in relation to anxiety, depression, and ICD related concerns 3 months post-implant.METHODS AND RESULTS: Consecutive implanted ICD patients were included as part of the WEB-based distress management programme for ICD patients (WEBCARE) trial from six...

  6. Determining the risks of magnetic resonance imaging at 1.5 tesla for patients with pacemakers and implantable cardioverter defibrillators.

    Science.gov (United States)

    Cohen, Jennifer D; Costa, Heather S; Russo, Robert J

    2012-12-01

    Conventional pacemaker and implantable cardioverter-defibrillator product labeling currently cautions against exposure to magnetic resonance imaging (MRI). However, there is a growing clinical need for MRI, without an acceptable alternative imaging modality in many patients with cardiac devices. The purpose of this study was to determine the risk of MRI at 1.5 T for patients with cardiac devices by measuring the frequency of device failures and clinically relevant device parameter changes. Data from a single-center retrospective review of 109 patients with pacemakers and implantable cardioverter-defibrillators (the MRI group) who underwent 125 clinically indicated MRI studies were compared to data from a prospective cohort of 50 patients with cardiac devices who did not undergo MRI (the control group). In the MRI group, there were no deaths, device failures requiring generator or lead replacement, induced arrhythmias, losses of capture, or electrical reset episodes. Decreases in battery voltage of ≥0.04 V occurred in 4%, pacing threshold increases of ≥0.5 V in 3%, and pacing lead impedance changes of ≥50 Ω in 6%. Although there were statistically significant differences between the MRI and control groups for the mean change in pacing lead impedance (-6.2 ± 23.9 vs 3.0 ± 22.1 Ω) and left ventricular pacing threshold (-0.1 ± 0.3 vs 0.1 ± 0.2 V), these differences were not clinically important. In conclusion, MRI in patients with cardiac devices resulted in no device or lead failures. A small number of clinically relevant changes in device parameter measurements were noted. However, these changes were similar to those in a control group of patients who did not undergo MRI. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Automatic remote monitoring utilizing daily transmissions: transmission reliability and implantable cardioverter defibrillator battery longevity in the TRUST trial.

    Science.gov (United States)

    Varma, Niraj; Love, Charles J; Schweikert, Robert; Moll, Philip; Michalski, Justin; Epstein, Andrew E

    2018-04-01

    Benefits of automatic remote home monitoring (HM) among implantable cardioverter defibrillator (ICD) patients may require high transmission frequency. However, transmission reliability and effects on battery longevity remain uncertain. We hypothesized that HM would have high transmission success permitting punctual guideline based follow-up, and improve battery longevity. This was tested in the prospective randomized TRUST trial. Implantable cardioverter defibrillator patients were randomized post-implant 2:1 to HM (n = 908) (transmit daily) or to Conventional in-person monitoring [conventional management (CM), n = 431 (HM disabled)]. In both groups, five evaluations were scheduled every 3 months for 15 months. Home Monitoring technology performance was assessed by transmissions received vs. total possible, and number of scheduled HM checks failing because of missed transmissions. Battery longevity was compared in HM vs. CM at 15 months, and again in HM 3 years post-implant using continuously transmitted data. Transmission success per patient was 91% (median follow-up of 434 days). Overall, daily HM transmissions were received in 315 795 of a potential 363 450 days (87%). Only 55/3759 (1.46%) of unsuccessful scheduled evaluations in HM were attributed to transmission loss. Shock frequency and pacing percentage were similar in HM vs. CM. Fifteen month battery longevity was 12% greater in HM (93.2 ± 8.8% vs. 83.5 ± 6.0% CM, P battery longevity was 50.9 ± 9.1% (median 52%) at 36 months. Automatic remote HM demonstrated robust transmission reliability. Daily transmission load may be sustained without reducing battery longevity. Home Monitoring conserves battery longevity and tracks long term device performance. ClinicalTrials.gov; NCT00336284.

  8. Standardized programming to reduce the burden of inappropriate therapies in implantable cardioverter defibrillators - Single centre follow up results

    Directory of Open Access Journals (Sweden)

    U. Boles

    2018-03-01

    Full Text Available Background: Current algorithms and device morphology templates have been proposed in current Implantable Cardioverter-Defibrillators (ICDs to minimize inappropriate therapies (ITS, but this has not been completely successful. Aim: Assess the impact of a deliberate strategy of using an atrial lead implant with standardized parameters; based on all current ICD discriminators and technologies, on the burden of ITS. Method: A retrospective single-centre analysis of 250 patients with either dual chamber (DR ICDs or biventricular ICDs (CRTDs over a (41.9 ± 27.3 month period was performed. The incidence of ITS on all ICD and CRTD patients was chronicled after the implementation of standardized programming. Results: 39 events of anti-tachycardial pacing (ATP and/or shocks were identified in 20 patients (8% incidence rate among patients. The total number of individual therapies was 120, of which 34% were inappropriate ATP, and 36% were inappropriate shocks. 11 patients of the 250 patients received ITS (4.4%. Of the 20 patients, four had ICDs for primary prevention and 16 for a secondary prevention. All the episodes in the primary indication group were inappropriate, while seven patients (43% of the secondary indication group experienced inappropriate therapies. Conclusions: The burden of ITS in the population of patients receiving ICDs was 4.4% in the presence of atrial leads. The proposed rationalized programming criteria seems an effective strategy to minimize the burden of inappropriate therapies and will require further validation. Keywords: Implantable cardioverter-defibrillator (ICDs, Inappropriate therapies, Standardized programming

  9. Classic conditioning and dysfunctional cognitions in patients with panic disorder and agoraphobia treated with an implantable cardioverter/defibrillator.

    Science.gov (United States)

    Godemann, F; Ahrens, B; Behrens, S; Berthold, R; Gandor, C; Lampe, F; Linden, M

    2001-01-01

    A model for the development of anxiety disorders (panic disorder with or without agoraphobia) is needed. Patients with an implantable cardioverter/defibrillator (ICD) are exposed to repeated electric shocks. If the theory of anxiety development by aversive classic conditioning processes is valid, these repeated shocks should lead to an increased risk of anxiety disorders. To study this hypothesis, we retrospectively studied 72 patients after implantation of an automatic ICD. Patients were assessed with the semistructured Diagnostic Interview of Psychiatric Disease 1 to 6 years after implantation of an automatic ICD. Panic disorder and/or agoraphobia was diagnosed in patients who fulfilled all DSM-III-R criteria for those conditions. Anxiety disorder developed in 15.9% of patients after ICD implantation. This was significantly related to the frequency of repeated defibrillation (shocks) to stop malignant ventricular arrhythmias. Dysfunctional cognitions are an additional vulnerability factor. The data support both the conditioning hypothesis and the cognitive model of anxiety development. These findings suggest that ICD patients are an appropriate risk population for a prospective study of the development of anxiety disorders.

  10. Psychometric properties of HeartQoL, a core heart disease-specific health-related quality of life questionnaire, in Danish implantable cardioverter defibrillator recipients

    DEFF Research Database (Denmark)

    Zangger, Graziella; Zwisler, Ann-Dorthe; Kikkenborg Berg, Selina

    2017-01-01

    Background Patient-reported health-related quality of life is increasingly used as an outcome measure in clinical trials and as a performance measure to evaluate quality of care. The objective of this study was to assess the psychometric properties of the Danish HeartQoL questionnaire, a core heart...... disease-specific health-related quality of life questionnaire, in implantable cardioverter defibrillator recipients. Design This study involved cross-sectional and test-retest study designs. Method Implantable cardioverter defibrillator recipients in the cross-sectional study completed the Heart......QoL, the Short-Form 36 Health Survey, and the Hospital Anxiety and Depression Scale. The HeartQoL structure, construct-related validity (convergent and discriminative) and reliability (internal consistency) were assessed. HeartQoL reproducibility (test-retest) was assessed in an independent sample of implantable...

  11. Beta-blocker therapy is not associated with symptoms of depression and anxiety in patients receiving an implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Kupper, Nina; Theuns, Dominic A M J

    2012-01-01

    Beta-blockers are frequently prescribed to implantable cardioverter-defibrillator (ICD) patients. Beta-blocker therapy has been proposed to induce emotional distress such as depression and anxiety, but a paucity of studies has examined the relationship between beta-blockers and distress. We...... investigated the association between beta-blocker therapy, including type and dosage, and symptoms of anxiety and depression in a consecutive cohort of patients receiving an ICD....

  12. Unmappable ventricular tachycardia after an old myocardial infarction. Long-term results of substrate modification in patients with an implantable cardioverter defibrillator

    OpenAIRE

    Alzand, B. S. N.; Timmermans, C. C. M. M.; Wellens, H. J. J.; Dennert, R.; Philippens, S. A. M.; Portegijs, P. J. M.; Rodriguez, LM.

    2011-01-01

    Purpose The frequent occurrence of ventricular tachycardia can create a serious problem in patients with an implantable cardioverter defibrillator. We assessed the long-term efficacy of catheter-based substrate modification using the voltage mapping technique of infarct-related ventricular tachycardia and recurrent device therapy. Methods The study population consisted of 27 consecutive patients (age 68 ± 8 years, 25 men, mean left ventricular ejection fraction 31 ± 9%) with an old myocardial...

  13. Current state of knowledge and experts' perspective on the subcutaneous implantable cardioverter-defibrillator.

    Science.gov (United States)

    Santini, Massimo; Cappato, Riccardo; Andresen, Dietrich; Brachmann, Johannes; Davies, D Wyn; Cleland, John; Filippi, Alessandro; Gronda, Edoardo; Hauer, Richard; Steinbeck, Gerhard; Steinhaus, David

    2009-06-01

    ICD implantation is today a well-recognized therapy to prevent sudden cardiac death. The available implantable devices at present need the use of permanent endocavitary leads which may cause, in some instances, serious troubles to the patients (lead dislodgement, ventricular perforation, lead infections, etc.). A new implantable defibrillator provided by only a subcutaneous lead is at present under evaluation. Its potential indications, usefulness benefits, and problems represent an interesting field of investigation and discussion. This paper describes the conclusions recently reached by a panel of experts, with regard to the potential role of an implantable subcutaneous defibrillator in the prevention of sudden cardiac death.

  14. Wearable cardioverter defibrillators for the prevention of sudden cardiac arrest: a health technology assessment and patient focus group study

    Directory of Open Access Journals (Sweden)

    Ettinger S

    2017-11-01

    Full Text Available Sabine Ettinger,1 Michal Stanak,1 Piotr Szymański,2 Claudia Wild,1 Romana Tandara Haček,3 Darija Erčević,3 Renata Grenković,3 Mirjana Huić3 1Ludwig Boltzmann Institute for Health Technology Assessment, Vienna, Austria; 2Institute of Cardiology, Warsaw, Poland; 3Department for Development, Research and Health Technology Assessment, Agency for Quality and Accreditation in Health Care and Social Welfare, Zagreb, Croatia Aim: To summarize the evidence on clinical effectiveness and safety of wearable cardioverter defibrillator (WCD therapy for primary and secondary prevention of sudden cardiac arrest in patients at risk. Methods: We performed a systematic literature search in databases including MEDLINE via OVID, Embase, the Cochrane Library, and CRD (DARE, NHS-EED, HTA. The evidence obtained was summarized according to GRADE methodology. A health technology assessment (HTA was conducted using the HTA Core Model® for rapid relative effectiveness assessment. Primary outcomes for the clinical effectiveness domain were all-cause and disease-specific mortality. Outcomes for the safety domain were adverse events (AEs and serious adverse events (SAEs. A focus group with cardiac disease patients was conducted to evaluate ethical, organizational, patient, social, and legal aspects of the WCD use. Results: No randomized- or non-randomized controlled trials were identified. Non-comparative studies (n=5 reported AEs including skin rash/itching (6%, false alarms (14%, and palpitations/light-headedness/fainting (9% and discontinuation due to comfort/lifestyle issues (16–22%, and SAEs including inappropriate shocks (0–2%, unsuccessful shocks (0–0.7%, and death (0–0.3%. The focus group results reported that experiencing a sense of security is crucial to patients and that the WCD is not considered an option for weeks or even months due to expected restrictions in living a “normal” life. Conclusion: The WCD appears to be relatively safe for short

  15. Use of implantable cardioverter defibrillators after out-of-hospital cardiac arrest: a prospective follow-up study

    Science.gov (United States)

    Parkash, Ratika; Tang, Anthony; Wells, George; Blackburn, Josée; Stiell, Ian; Simpson, Christopher; Dorian, Paul; Yee, Raymond; Cameron, Doug; Connolly, Stuart; Birnie, David; Nichol, Graham

    2004-01-01

    Background Survivors of out-of-hospital cardiac arrest are at high risk of recurrent arrests, many of which could be prevented with implantable cardioverter defibrillators (ICDs). We sought to determine the ICD insertion rate among survivors of out-of-hospital cardiac arrest and to determine factors associated with ICD implantation. Methods The Ontario Prehospital Advanced Life Support (OPALS) study is a prospective, multiphase, before–after study assessing the effectiveness of prehospital interventions for people experiencing cardiac arrest, trauma or respiratory arrest in 19 Ontario communities. We linked OPALS data describing survivors of cardiac arrest with data from all defibrillator implantation centres in Ontario. Results From January 1997 to April 2002, 454 patients in the OPALS study survived to hospital discharge after experiencing an out-of-hospital cardiac arrest. The mean age was 65 (standard deviation 14) years, 122 (26.9%) were women, 398 (87.7%) had a witnessed arrest, 372 (81.9%) had an initial rhythm of ventricular tachycardia or ventricular fibrillation (VT/VF), and 76 (16.7%) had asystole or another arrhythmia. The median cerebral performance category at discharge (range 1–5, 1 = normal) was 1. Only 58 (12.8%) of the 454 patients received an ICD. Patients with an initial rhythm of VT/VF were more likely than those with an initial rhythm of asystole or another rhythm to undergo device insertion (adjusted odds ratio [OR] 9.63, 95% confidence interval [CI] 1.31–71.50). Similarly, patients with a normal cerebral performance score were more likely than those with abnormal scores to undergo ICD insertion (adjusted OR 12.52, 95% CI 1.74–92.12). Interpretation A minority of patients who survived cardiac arrest underwent ICD insertion. It is unclear whether this low usage rate reflects referral bias, selection bias by electrophysiologists, supply constraint or patient preference. PMID:15505267

  16. Decision-Making of Patients With Implantable Cardioverter-Defibrillators at End of Life: Family Members' Experiences.

    Science.gov (United States)

    Lee, Mei Ching; Sulmasy, Daniel P; Gallo, Joseph; Kub, Joan; Hughes, Mark T; Russell, Stuart; Kellogg, Anela; Owens, Sharon G; Terry, Peter; Nolan, Marie T

    2017-07-01

    Many patients with advanced heart failure (HF) experience the life-extending benefits of implantable cardioverter-defibrillators (ICD), but at the end stage of HF, patients may experience shocks with increasing frequency and change the plan for end-of-life (EOL) care including the deactivation of the ICD. This report describes family members' experiences of patients with ICD making decisions at EOL. Understanding the decision-making of patients with ICD at EOL can promote informed decision-making and improve the quality of EOL care. This pilot study used a mixed methods approach to test the effects of a nurse-guided discussion in decision-making about ICD deactivation (turning off the defibrillation function) at the EOL. Interviews were conducted, audiotaped, and transcribed in 2012 to 2013 with 6 family members of patients with advanced HF and ICDs. Three researchers coded the data and identified themes in 2014. Three main themes described family members' experiences related to patients having HF with ICDs making health-care decision at EOL: decision-making preferences, patients' perception on ICD deactivation, and communication methods. Health-care providers need to have knowledge of patients' decision-making preferences. Preferences for decision-making include the allowing of appropriate people to involve and encourages direct conversation with family members even when advance directives is completed. Information of ICD function and the option of deactivation need to be clearly delivered to patients and family members. Education and guidelines will facilitate the communication of the preferences of EOL care.

  17. Implantable Cardioverter-defibrillator Therapy for Hypertrophic Cardiomyopathy: Usefulness in Primary and Secondary Prevention.

    Science.gov (United States)

    Sarrias, Axel; Galve, Enrique; Sabaté, Xavier; Moya, Àngel; Anguera, Ignacio; Núñez, Elaine; Villuendas, Roger; Alcalde, Óscar; García-Dorado, David

    2015-06-01

    Hypertrophic cardiomyopathy is a frequent cause of sudden death. Clinical practice guidelines indicate defibrillator implantation for primary prevention in patients with 1 or more risk factors and for secondary prevention in patients with a history of aborted sudden death or sustained ventricular arrhythmias. The aim of the present study was to analyze the follow-up of patients who received an implantable defibrillator following the current guidelines in nonreferral centers for this disease. This retrospective observational study included all patients who underwent defibrillator implantation between January 1996 and December 2012 in 3 centers in the province of Barcelona. The study included 69 patients (mean age [standard deviation], 44.8 [17] years; 79.3% men), 48 in primary prevention and 21 in secondary prevention. The mean number of risk factors per patient was 1.8 in the primary prevention group and 0.5 in the secondary prevention group (P=.029). The median follow-up duration was 40.5 months. The appropriate therapy rate was 32.7/100 patient-years in secondary prevention and 1.7/100 patient-years in primary prevention (P<.001). Overall mortality was 10.1%. Implant-related complications were experienced by 8.7% of patients, and 13% had inappropriate defibrillator discharges. In patients with a defibrillator for primary prevention, the appropriate therapy rate is extremely low, indicating the low predictive power of the current risk stratification criteria. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  18. Depression, psychological distress, and quality of life in patients with cardioverter defibrillator with or without cardiac resynchronization therapy.

    Science.gov (United States)

    Knackstedt, Christian; Arndt, Marlies; Mischke, Karl; Marx, Nikolaus; Nieman, Fred; Kunert, Hanns Jürgen; Schauerte, Patrick; Norra, Christine

    2014-05-01

    Congestive heart failure is frequent and leads to reduced exercise capacity, reduced quality of life (QoL), and depression in many patients. Cardiac resynchronization therapy (CRT) and implantable cardioverter defibrillators (ICD) offer therapeutic options and may have an impact on QoL and depression. This study was performed to evaluate physical and mental health in patients undergoing ICD or combined CRT/ICD-implantation (CRT-D). Echocardiography, spiroergometry, and psychometric questionnaires [Beck Depression Inventory, General World Health Organization Five Well-being Index (WHO-5), Brief Symptom Inventory and 36-item Short Form (SF-36)] were obtained in 39 patients (ICD: 17, CRT-D: 22) at baseline and 6-month follow-up (FU) after device implantation. CRT-D patients had a higher NYHA class and broader left bundle branch block than ICD patients at baseline. At FU, ejection fraction (EF), peak oxygen uptake, and NYHA class improved significantly in CRT-D patients but remained unchanged in ICD patients. Patients with CRT-D implantation showed higher levels of depressive symptoms, psychological distress, and impairment in QoL at baseline and FU compared to ICD patients. These impairments remained mostly unchanged in all patients after 6 months. Overall, these findings imply that there is a need for careful assessment and treatment of psychological distress and depression in ICD and CRT-D patients in the course of device implantation as psychological burden seems to persist irrespective of physical improvement.

  19. Sex is associated with differences in individual trajectories of change in social health after implantable cardioverter-defibrillator.

    Science.gov (United States)

    Lauck, Sandra B; Sawatzky, Richard; Johnson, Joy L; Humphries, Karin; Bennett, Matthew T; Chakrabarti, Santabhanu; Kerr, Charles R; Tung, Stanley; Yeung-Lai-Wah, John A; Ratner, Pamela A

    2015-03-01

    Social health is a dimension of quality of life, and refers to people's involvement in, and satisfaction with social roles, responsibilities, and activities. The implantable cardioverter-defibrillator is associated with changes in overall quality of life, but little is known about sex differences in individual trajectories of change in social health. We prospectively measured changes in 3 subscales of the SF-36v2 generic health questionnaire (role physical, role emotional, and social functioning), 2 Patient-Reported Outcomes Measurement Information System short forms (satisfaction with participation in social roles and satisfaction with participation in discretionary social activities), and the Florida Patient Acceptance Survey before and at 1, 2, and 6 months after implantation. Individual growth models of temporal change were estimated. The scores of the 6 indicators improved with time. The unconditional model demonstrated significant (fixed effects: Pchange in the scores of 3 of the 6 measures. Although men's mean scores exceeded women's mean scores on all indicators at baseline (range of relative mean difference: 11.0% to 17.8%), the rate of women's change resulted in a reversal in relative standing at 6 months after implantation, with the mean scores of women exceeding the men's by 4.5% to 5.6%. Men and women differed in their trajectories of change in social health, both in terms of their starting points (ie, baseline scores) and their rates of change. © 2015 American Heart Association, Inc.

  20. Safety of sports participation in patients with implantable cardioverter defibrillators: a survey of heart rhythm society members.

    Science.gov (United States)

    Lampert, Rachel; Cannom, David; Olshansky, Brian

    2006-01-01

    Safety of Sports for ICD Patients. The safety of sports participation for patients with implantable cardioverter defibrillators (ICDs) is unknown, and recommendations among physicians may vary widely. The purposes of this study were to determine current practice among patients with ICDs and their physicians regarding sports participation, and to determine how many physicians have cared for patients who have sustained adverse events during sports participation. A survey was mailed to all 1,687 U.S. physician members of the Heart Rhythm Society. Among 614 respondent physicians, recommendations varied widely. Only 10% recommended avoidance of all sports more vigorous than golf. Seventy-six percent recommended avoidance of contact, and 45% recommend avoidance of competitive sports. Most (71%) based restrictions on patients' underlying heart disease. Regardless of recommendations, most physicians (71%) reported caring for patients who participated in sports, including many citing vigorous, competitive sports, most commonly cited were basketball, running, and skiing. ICD shocks during sports were common, cited by 40% of physicians. However, few adverse consequences were reported. One percent of physicians reported known injury to patient (all but 3 minor); 5%, injury to the ICD system, and weightlifting and golf. Physician recommendations for sports participation for patients with ICDs varies widely. Many patients with ICDs do participate in vigorous and even competitive sports. While shocks were common, significant adverse events were rare.

  1. Failed anti-tachycardia pacing can be used to differentiate atrial arrhythmias from ventricular tachycardia in implantable cardioverter-defibrillators.

    Science.gov (United States)

    Michael, Kevin A; Enriquez, Andres; Baranchuk, Adrian; Haley, Charlotte; Caldwell, Jane; Simpson, Christopher S; Abdollah, Hoshiar; Redfearn, Damian P

    2015-01-01

    Atrial fibrillation/tachycardia (AF/AT) may result in inappropriate therapies in implantable cardioverter-defibrillators (ICDs). The post-pacing interval (PPI) and tachycardia cycle length difference (PPI - TCL) has been previously demonstrated to indicate the proximity of the pacing site to a tachycardia origin. We postulated that the PPI and PPI - TCL would be greater in AT/AF vs. ventricular tachycardia (VT) after episodes of failed anti-tachycardia pacing (ATP). This was a single-centre, retrospective study evaluating consecutive patients implanted with dual (DR)/biventricular (BIV) ICDs. Stored electrograms were used to determine whether the ATP captured the arrhythmia and the arrhythmia did not present with primary or secondary termination. Measurements were done using manual calipers. A total of 155 patients were included. There were 79 BIV and 76 DR devices. In total, 39 episodes were identified in 20 patients over a 23-month follow-up period. A total of 76 sequences of ATP (burst/ramp) were delivered, 28 (37%) of them inappropriate. Fifty-one events (18 AT/AF and 33 VT) were compared. The mean PPI was 693 ± 96 vs. 512 ± 88 ms (P failed ATP differs significantly between AF/AT and VT and are therefore useful indices to discriminate between supraventricular tachycardia and VT in ICDs. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  2. Association of air pollution with increased incidence of ventricular tachyarrhythmias recorded by implantable cardioverter defibrillators: Vulnerable patients to air pollution.

    Science.gov (United States)

    Kim, In-Soo; Sohn, Jungwoo; Lee, Seung-Jun; Park, Jin-Kyu; Uhm, Jae-Sun; Pak, Hui-Nam; Lee, Moon-Hyoung; Kim, Changsoo; Joung, Boyoung

    2017-08-01

    This study investigated the acute effects of exposure to air pollution on ventricular tachyarrhythmias (VTAs) in an East Asian population. The association between air pollution and VTA has not yet been studied in an East Asian country affected by the Asian dust phenomenon, which worsens air quality. The study cohort consisted of 160patients with implantable cardioverter defibrillator (ICD) devices in the Seoul metropolitan area who were followed for 5.5±3.8years. We used ICD records of VTAs and matched these with hourly measurements of air pollutant concentrations and meteorological data. Fine particle mass and gaseous air pollution plus temperature and relative humidity were measured hourly during the study period. During the study period, 1064 VTA events including 204 instances of ventricular fibrillation (VF) were observed. We found a statistically significant association between overall VTA events and SO 2 (lag 24h; OR 1.49, 95%CI 1.16-1.92, p=0.002), PM 10 (lag 2h; OR 2.56, 95%CI 2.03-3.23, pair pollution and VTA were observed in a metropolitan area of an East Asian country. Exposures to SO 2 , PM 10 , NO 2 , and CO were significantly associated with VTAs in ICD patients with SHD. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Implantable cardioverter-defibrillators improve survival after coronary artery bypass grafting in patients with severely impaired left ventricular function

    Directory of Open Access Journals (Sweden)

    Pasque Michael K

    2007-01-01

    Full Text Available Abstract Objective Patients with severe left ventricular (LV dysfunction have a poor long term survival despite complete surgical revascularization. Recent data suggests that the use of Implantable Cardioverter-Defibrillator (ICD improves survival in patients with severe LV dysfunction. We compared the survival impact of ICD implantation in patients with severe LV dysfunction who underwent CABG. Methods Between January 1996 and August 2004, 305 patients with LV ejection fraction (EF ≤25% had CABG surgery at our institution. Demographics of patients who had received an ICD (ICD+ in the post -operative period was compared to those without ICD (ICD-. Survival was evaluated by the Kaplan-Meier method. Results Of the entire group, 35 (11.5% patients received an ICD with a median of 2 (+/-2 years after CABG. Indication for ICD implantation was clinical evidence of non sustained ventricular tachycardia (NSVT. There were no differences between the 2 groups with respect to age, gender, NYHA classification, number of bypasses, or other co-morbidities. Survival at 1, 3 and 5 years was 88%, 79%, and 67% for the ICD- group compared to 94%, 89% and 83% for the ICD+ group, respectively (figure, p Conclusion Implantation of ICD after CABG confers improved short and long term survival benefit to patients with severe LV dysfunction. Prophylactic ICD implantation in the setting of severe LV dysfunction and CABG surgery should be considered.

  4. Do implantable cardioverter defibrillators improve survival in patients with severe left ventricular systolic dysfunction after coronary artery bypass graft surgery?

    Science.gov (United States)

    Fazal, Iftikhar A; Bates, Matthew G D; Matthews, Iain G; Turley, Andrew J

    2011-06-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether implantable cardioverter defibrillators (ICD) improve survival in patients with severe left ventricular systolic dysfunction (LVSD) after coronary artery bypass graft (CABG) surgery. ICDs are designed to terminate potentially fatal cardiac tachyarrhythmias. A right ventricular lead is mandatory for detection, pacing and defibrillation capabilities. Dual chamber ICDs have an additional right atrial lead and are used for patients with conventional atrioventricular pacing indications. More sophisticated, biventricular devices exist to provide cardiac resynchronisation therapy (CRT) in addition to defibrillation (CRT-D). ICDs have been extensively investigated in patients with LVSD post myocardial infarction and in patients with non-ischaemic cardiomyopathy for both secondary prevention (history of ventricular arrhythmias) and primary prevention (deemed high risk for ventricular arrhythmias). This best evidence topic aims to review the evidence and its applicability to patients post CABG. Nine hundred and sixteen papers were identified using the search method outlined. Eight randomised controlled trials, two meta-analyses, and one non-randomised trial, in addition to international guidelines presented the best evidence to answer the clinical question. The current evidence base and guidelines suggest that ICDs should be considered for all patients with LVSD [ejection fraction (EF) ≤30-40%] receiving optimal pharmacological management, who are ≥40 days post MI [four weeks for National Institute for Health and Clinical Excellence (NICE)] and in New York Heart Association (NYHA) class I-III. UK NICE guidelines require in addition; non-sustained ventricular tachycardia (NSVT) on a Holter monitor and inducible ventricular tachycardia at electrophysiological study for EF between 30 and 35%; or a QRS >120 ms if EF <30%. The North American guidelines

  5. [Impact of metoprolol use in the treatment of patients with electrical-storm after cardioverter defibrillators implantation].

    Science.gov (United States)

    Yu, Jin-bo; Yang, Bing; Xu, Dong-jie; Chen, Ming-long; Shan, Qi-jun; Zou, Jian-gang; Chen, Chun; Zhang, Feng-xiang; Hou, Xiao-feng; Li, Wen-qi; Zhang, Rong; Cao, Ke-jiang

    2011-08-01

    To explore the effectiveness of the metoprolol dosage adjustment on reducing the incidence of electrical-storm (ES) in patients with Implantable Cardioverter Defibrillators (ICDs). Data from patients with ICD implantation between Jan, 2003 and Jun, 2006 in our hospital were retrospectively analyzed. ES was defined as either ≥ 3 times of ventricular tachyarrhythmias (VTAs) resulting in ICD therapy or VTAs lasting more than 30 s detected by ICD without any therapy within 24 hours. During a follow-up period of (27.5 ± 21.2) months, ES was recorded in 39 cases [34 males, average age (52.0 ± 13.1) years] out of 119 patients (32.8%) and 9 patients died after ES. During the period of storm attack, ES was successfully controlled in 25/30 patients by various interventions, including predisposing factors corrected in 5 cases, ICD reprogramming and antiarrhythmic drugs therapy optimized in 16 cases (one received intravenous injection of metoprolol), and VTAs eliminated by catheter ablation in 4 cases. ES was spontaneously resolved in the remaining 5 cases. In the chronic phase, 2 patients with Brugada syndrome were treated with Quinidine mono-therapy while the dosage of metoprolol was adjusted in the remaining 23 patients and the dosage of metoprolol was increased gradually from (26.8 ± 13.9) mg/d to (88.9 ± 53.5) mg/d without any adverse effects (9 patients received also oral amiodarone 200 mg/d). Post dosage adjustment, the total VTA episodes [(1.9 ± 1.7) times/month vs. (0.8 ± 0.6) times/month, P = 0.004], incidence of antitachycardia pacing therapies [(4.2 ± 3.8) runs/month vs. (2.3 ± 2.0) runs/month, P = 0.003], as well as electrical cardioversion or defibrillation [(1.1 ± 0.9) times/month vs. (0.4 ± 0.2) times/month, P = 0.001] were significantly decreased. ES was not controlled until a extremely high dosage [225 - 300 (255.3 ± 41.7) mg/d] of metoprolol was reached in the remaining 5 patients. Metoprolol use is essential and its dosage should be

  6. Is it safe to allow patients with implantable cardioverter-defibrillators to drive? Learnings from a single center experience.

    Science.gov (United States)

    Curnis, Antonio; Mascioli, Giosue; Bontempi, Luca; Cerini, Manuel; Bignotti, Tommaso; Bonetti, Gabriele; Dei Cas, Livio

    2008-12-01

    Implantable cardioverter-defibrillator (ICD) implant indications have widened in recent years after the publication of the Multicenter Automatic Defibrillator Implantation Trial 2 and the Sudden Cardiac Death in Heart Failure Trial. On the contrary, guidelines on resumption of driving after ICD implant were published almost 10 years ago when the ICD implant rate was much lower and candidates were generally older. The overall objective of our study was to evaluate whether patients implanted with ICDs have higher risk than the general driving population. The specific aim of the study was to verify the rate of car accidents in patients implanted with an ICD, both for primary and secondary indication, and compare this with the rate of accidents in the general population. The primary end point of the study was the annual car accident rate; the secondary end point was to determine if there were subgroups of patients with a higher risk of car accidents. All patients (612) followed up in our outpatient clinic were sent a questionnaire in which they were asked five questions regarding their driving habits before and after ICD implant and, specifically, whether they had been involved in a car accident after the implant. Two hundred eighty-six patients (47%) responded to the questionnaire. Seventy-one patients had never driven; two patients were forbidden to drive for professional reasons (one bus and one truck driver). Two hundred thirteen (74.5% of all responding) patients (201 men, mean age 62 +/- 11 years) continued to drive after ICD implant. During the follow-up (1430 +/- 920 days) 11 patients had been involved in car accidents and, importantly 10 out of 11 were innocent bystanders. Thus, in 996 patient-years, 11 events happened, yielding an annual event rate of 1.1% per patient-years (and only 0.1% in which the driver could had been responsible). Car accidents are infrequent in patients implanted with an ICD, and - in any case - not more frequent than in the general

  7. Safety of implantable pacemakers and cardioverter defibrillators in the magnetic field of a novel remote magnetic navigation system.

    Science.gov (United States)

    Jilek, Clemens; Tzeis, Stylianos; Reents, Tilko; Estner, Heidi-Luise; Fichtner, Stephanie; Ammar, Sonia; Wu, Jinjin; Hessling, Gabriele; Deisenhofer, Isabel; Kolb, Christof

    2010-10-01

    Electromagnetic interference with pacemaker and implantable cardioverter defibrillator (ICD) systems may cause temporary or permanent system malfunction of implanted devices. The aim of this study was to evaluate potential interference of a novel magnetic navigation system with implantable rhythm devices. A total of 121 devices (77 pacemakers, 44 ICDs) were exposed to an activated NIOBE II® Magnetic Navigation System (Stereotaxis, St. Louis, MO, USA) at the maximal magnetic field strength of 0.1 Tesla and evaluated in vitro with respect to changes in parameter settings of the device, changes of the battery status/detection of elective replacement indication, or alterations of data stored in the device. A total of 115 out of 121 (95%) devices were free of changes in parameter settings, battery status, and internally stored data after repeated exposition to the electromagnetic field of the remote magnetic navigation system. Interference with the magnetic navigation field was observed in 6 pacemakers, resulting in reprogramming to a power-on-reset mode with or without detection of the elective replacement indication in 5 devices and abnormal variance of battery status in one device. All pacemakers could be reprogrammed to the initial modes and the battery status proved to be normal some minutes after the pacemakers had been removed from the magnetic field. Interference of a remote magnetic navigation system (at maximal field strength) with pacemakers and ICDs not connected to leads with antitachycardic detection and therapies turned off is rare. Occurring functional abnormalities could be reprogrammed in our sample. An in vitro study will give information about interference of devices connected to leads. © 2010 Wiley Periodicals, Inc.

  8. Impact of Moderate to Severe Renal Impairment on Mortality and Appropriate Shocks in Patients with Implantable Cardioverter Defibrillators

    Directory of Open Access Journals (Sweden)

    Venkata M. Alla

    2010-01-01

    Full Text Available Background. Due to underrepresentation of patients with chronic kidney disease (CKD in large Implantable-Cardioverter Defibrillator (ICD clinical trials, the impact of ICD remains uncertain in this population. Methods. Consecutive patients who received ICD at Creighton university medical center between years 2000–2004 were included in a retrospective cohort after excluding those on maintenance dialysis. Based on baseline Glomerular filtration rate (GFR, patients were classified as severe CKD: GFR < 30 mL/min; moderate CKD: GFR: 30–59 mL/min; and mild or no CKD: GFR ≥ 60 mL/min. The impact of GFR on appropriate shocks and survival was assessed using Kaplan-Meier method and Generalized Linear Models (GLM with log-link function. Results. There were 509 patients with a mean follow-up of 3.0 + 1.3 years. Mortality risk was inversely proportional to the estimated GFR: 2 fold higher risk with GFR between 30–59 mL/min and 5 fold higher risk with GFR < 30 mL/min. One hundred and seventy-seven patients received appropriate shock(s; appropriate shock-free survival was lower in patients with severe CKD (GFR < 30 compared to mild or no CKD group (2.8 versus 4.2 yrs. Conclusion. Even moderate renal dysfunction increases all cause mortality in CKD patients with ICD. Severe but not moderate CKD is an independent predictor for time to first appropriate shock.

  9. Interaction between shock coils increased the incidence of inappropriate therapies and lead failure in implantable cardioverter defibrillator.

    Science.gov (United States)

    El Garhy, Mohammad; Ohlow, Marc-Alexander; Lauer, Bernward

    Shock coil interaction in patients with multiple implantable cardioverter defibrillator (ICD) leads is occasionally observed. We aimed to evaluate the incidence of shock coil interaction and its clinical relevance. All ICD patients (646 patients) who came to follow up control in our ICD ambulance between January 1, 2011, and December 31, 2011 in the department of cardiology in Bad Berka hospital were retrospectively evaluated in this study. All baseline demographic, clinical, and procedural characteristics and postoperative chest x ray in postero-anterior and lateral view as well as clinical and ICD follow up data were evaluated. Among 646 patients 42 had multiple ICD leads (6.5%) of whom 36 patients (5.5% of total cohort patients and 85.7% of patients with multiple ICD leads) had shock coil interaction and presented the study group (Group I). The control group (Group II) consisted of 610 patients without coil-coil interaction including patients with single shock lead (604 patients) or patients with multiple leads but without interaction between shock coils (6 patients). Inappropriate anti-tachycardia therapies and RV lead revisions were more frequent in patients with interaction between shock coils (Group I vs Group II: 27.7% and 5.7%; p = 0.049 and 30.6% vs 6.4; p = 0.0001, respectively). Interaction between shock coils may be one of possible causes of lead failure and resulted in inappropriate therapies and subsequent lead revision. Copyright © 2018 Indian Heart Rhythm Society. Production and hosting by Elsevier B.V. All rights reserved.

  10. Radiotherapy and risk of implantable cardioverter-defibrillator malfunctions: experimental data from direct exposure at increasing doses.

    Science.gov (United States)

    Zecchin, Massimo; Artico, Jessica; Morea, Gaetano; Severgnini, Mara; Bianco, Elisabetta; De Luca, Antonio; Fantasia, Anna Zorzin; Salvatore, Luca; Milan, Vittorino; Lucarelli, Matteo; Dissegna, Roberta; Cannatà, Antonio; Sinagra, Gianfranco

    2018-04-01

    During radiotherapy, in patients with implantable cardioverter-defibrillators (ICDs) malfunctions are considered more likely if doses more than 2 Gy reach the ICD site; however, most malfunctions occur with high-energy (>10 MV) radiations, and the risk is less defined using 6-MV linear accelerators. The purpose of the study is to experimentally evaluate the occurrence of malfunctions in ICDs radiated with a 6-MV linear accelerator at increasing photon doses. Thirty-two ICDs from all manufacturers (31 explanted and one demo) were evaluated; all devices with a sufficient battery charge underwent multiple radiations with a 6-MV photon beam reaching a cumulative dose at ICD site of 0.5, 1, 2, 3, 5 and 10 Gy and interrogated after every session. All antitachycardia therapies were left enabled; two ICDs were connected to a rhythm simulator (one simulating a complete atrioventricular block without ventricular activity) and visually monitored by external ECG and the ICD programmer during radiation. Thirteen ICDs were excluded before radiation because of battery depletion; after radiation up to the cumulative dose at the cardiac implantable electronic device site of 10 Gy, in the remaining 19 devices, programmation and battery charge remained unchanged and no switch to safety mode was observed; oversensing, pacing inhibition or inappropriate antitachycardia therapy were neither recorded nor visually observed during radiation. With a low-energy accelerator, neither malfunctions nor electromagnetic interferences were detected radiating the ICDs at doses usually reaching the ICD pocket during radiotherapy sessions. In this context, magnet application to avoid oversensing and inappropriate therapy seems, therefore, useless.

  11. Ventricular tachyarrhythmias and mortality in patients with an implantable cardioverter defibrillator: impact of depression in the MIDAS cohort.

    Science.gov (United States)

    Mastenbroek, Mirjam H; Versteeg, Henneke; Jordaens, Luc; Theuns, Dominic A M J; Pedersen, Susanne S

    2014-01-01

    We examined whether depression is independently associated with implantable cardioverter defibrillator (ICD) therapy for ventricular tachyarrhythmias and mortality. A cohort of 430 consecutive patients with a first-time ICD (79% men; mean [standard deviation] age = 57.8 [12.1] years) completed the Hospital Anxiety and Depression Scale 1 day before implantation. During follow-up, the ICD was interrogated at 3-month intervals. Cox proportional hazard regression analyses were used to examine the impact of depression on time to first appropriate ICD therapy and all-cause mortality during a median follow-up period of 3.8 years. Of all patients, 108 (25.1%) were depressed. Depression was not associated with time to first appropriate ICD therapy (unadjusted hazard ratio [HR] = 1.07, 95% confidence interval [CI] = 0.73-1.56). However, depression was associated with an increased risk for all-cause mortality (unadjusted HR = 2.18, 95% CI = 1.36-3.49). Depression remained independently associated with all-cause mortality (HR = 1.94, 95% CI = 1.06-3.54, p = .031), after adjusting for demographic and clinical characteristics. Patients who remained depressed during the first 3 months after implantation were at greatest risk for dying (HR = 2.88, 95% CI = 1.29-6.45, p = .010). The current study showed that depression at the time of implant is not associated with time to first appropriate ICD therapy but almost doubled the risk for all-cause mortality in patients with an ICD. Patients with persistent depression during the first 3 months after implantation face the greatest risk of dying. Current evidence indicates that multifactorial interventions are likely to be the most successful in terms of reducing distress. Whether this translates into enhanced survival has yet to be determined.

  12. Attitudes of older adults with serious competing health risks toward their implantable cardioverter-defibrillators: a pilot study.

    Science.gov (United States)

    Green, Ariel R; Boyd, Cynthia M; Rickard, John; Gomon, Robert; Leff, Bruce

    2015-12-23

    In elderly heart failure patients, the survival benefit of implantable cardioverter-defibrillators (ICDs) may be attenuated due to competing health risks, and the risk of adverse outcomes magnified. Our objective was to examine older adults' attitudes towards ICD implantation in the context of competing health risks, exploring the determinants of ICD decision-making among a group of patients who had faced the decision in the past. Telephone survey with a qualitative component. Patients were age ≥70 with single- or dual-chamber ICDs from a single academic cardiac device clinic. Health status was assessed with the Vulnerable Elders Survey (VES-13). Responses to open-ended questions were transcribed verbatim; an "editing analysis" approach was used to extract themes. Forty-four ICD recipients participated (mean age 77.5 years). Nineteen participants (43%) had VES-13 scores ≥3, indicating a 50% likelihood of death or functional decline within 2 years. Twenty-one participants (48%) had received prior ICD shocks. Forty participants (91%) said they would "definitely" choose to get an ICD again in their current health. By and large, patients revealed a strong desire to extend life, expressed complete confidence in the lifesaving capabilities of their ICDs, and did not describe consideration of competing health risks. In this pilot telephone survey with a qualitative component, nearly all older adults with ICDs would still choose to get an ICD despite high short-term risk of death or health deterioration. These findings suggest the need to partner more effectively with patients and families to decide how best to use medical technologies, particularly for older adults with competing risks.

  13. Prospective Randomized Evaluation of Implantable Cardioverter-Defibrillator Programming in Patients With a Left Ventricular Assist Device.

    Science.gov (United States)

    Richardson, Travis D; Hale, Leslie; Arteaga, Christopher; Xu, Meng; Keebler, Mary; Schlendorf, Kelly; Danter, Matthew; Shah, Ashish; Lindenfeld, JoAnn; Ellis, Christopher R

    2018-02-23

    Ventricular arrhythmias are common in patients with left ventricular assist devices (LVADs) but are often hemodynamically tolerated. Optimal implantable cardioverter defibrillator (ICD) tachy-programming strategies in patients with LVAD have not been determined. We sought to determine if an ultra-conservative ICD programming strategy in patients with LVAD affects ICD shocks. Adult patients with an existing ICD undergoing continuous flow LVAD implantation were randomized to standard ICD programming by their treating physician or an ultra-conservative ICD programming strategy utilizing maximal allowable intervals to detection in the ventricular fibrillation and ventricular tachycardia zones with use of ATP. Patients with cardiac resynchronization therapy (CRT) devices were also randomized to CRT ON or OFF. Patients were followed a minimum of 6 months. The primary outcome was time to first ICD shock. Among the 83 patients studied, we found no statistically significant difference in time to first ICD shock or total ICD shocks between groups. In the ultra-conservative group 16% of patients experienced at least one shock compared with 21% in the control group ( P =0.66). There was no difference in mortality, arrhythmic hospitalization, or hospitalization for heart failure. In the 41 patients with CRT ICDs fewer shocks were observed with CRT-ON but this was not statistically significant: 10% of patients with CRT-ON (n=21) versus 38% with CRT-OFF (n=20) received shocks ( P =0.08). An ultra-conservative programming strategy did not reduce ICD shocks. Programming restrictions on ventricular tachycardia and ventricular fibrillation zone therapy should be reconsidered for the LVAD population. The role of CRT in patients with LVAD warrants further investigation. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01977703. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  14. Implantable cardioverter defibrillator therapy in pediatric and congenital heart disease patients: a single tertiary center experience in Korea

    Directory of Open Access Journals (Sweden)

    Bo Kyung Jin

    2013-03-01

    Full Text Available Purpose: The use of implantable cardioverter defibrillators (ICDs to prevent sudden cardiac death is increasing in children and adolescents. This study investigated the use of ICDs in children with congenital heart disease. Methods: This retrospective study was conducted on the clinical characteristics and effectiveness of ICD implantation at the department of pediatrics of a single tertiary center between 2007 and 2011. Results: Fifteen patients underwent ICD implantation. Their mean age at the time of implantation was 14.5±5.4 years (range, 2 to 22 years. The follow-up duration was 28.9±20.4 months. The cause of ICD implantation was cardiac arrest in 7, sustained ventricular tachycardia in 6, and syncope in 2 patients. The underlying disorders were as follows: ionic channelopathy in 6 patients (long QT type 3 in 4, catecholaminergic polymorphic ventricular tachycardia [CPVT] in 1, and J wave syndrome in 1, cardiomyopathy in 5 patients, and postoperative congenital heart disease in 4 patients. ICD coils were implanted in the pericardial space in 2 children (ages 2 and 6 years. Five patients received appropriate ICD shock therapy, and 2 patients received inappropriate shocks due to supraventricular tachycardia.During follow-up, 2 patients required lead dysfunction-related revision. One patient with CPVT suffered from an ICD storm that was resolved using sympathetic denervation surgery. Conclusion: The overall ICD outcome was acceptable in most pediatric patients. Early diagnosis and timely ICD implantation are recommended for preventing sudden death in high-risk children and patients with congenital heart disease.

  15. Pacemakers and implantable cardioverter defibrillators, unknown to chest radiography: Review, complications and systematic reading

    International Nuclear Information System (INIS)

    Alandete Germán, Salvador Pascual; Isarria Vidal, Santiago; Domingo Montañana, María Luisa; De la vía Oraá, Esperanza; Vilar Samper, José

    2015-01-01

    Highlights: •Radiologists have an important function in the evaluation of these devices. •We revise their radiological appearances and possible complications. •The knowledge in normal aspects and complications is important for radiologist. •To ensure an accurate reading of the chest x-ray, we present a systematic approach. -- Abstract: Chest X-ray is the imaging technique of choice for an initial study of pacemakers and implantable cardio-defibrillators (ICD). Radiologists have an important role in the evaluation of its initial placement and in the assessment during its follow-up. For this reason, it is necessary to know not only the different existing devices and its components but also the reasons of malfunction or possible complications. The purpose of this article is to do a systematic review of the different types of pacemakers and ICD. We review their usual radiological appearances, the possible complications which might take place and its causes of malfunctioning

  16. Management of radiation oncology patients with implanted cardiac pacemakers or implant able cardioverter defibrilators; Tratamiento de pacientes en radioterapia con marcapasos o desfibriladores automaticos implantables

    Energy Technology Data Exchange (ETDEWEB)

    Martin Martin, G.

    2012-07-01

    The increase in life expectancy along with the technological development in the last decades has resulted in an increase in the number of patients requiring pacemaker implants or implantable cardioverter defibrillators worldwide. An increase in the number of patients with implanted cardiac devices in radiotherapy is also expected due to the risk factors in common between heart disease and cancer. In 1994 the American Association of Physicists in Medicine (AAPM) released a report about the management of radiation oncology patients with implanted cardiac pacemakers. The addition of new technologies, both in radiotherapy units and in the manufacturing process of heart devices, has shown the need for an updated protocol for the management of these patients. In this work, the most important articles published after the report of the AAPM have been compiled, in order to analyze the effects not previously studied such as dose rate, scattered radiation, electromagnetic interference or random failures produced by neutrons and protons. Additionally, the latest recommendations given by the manufacturers have been analyzed and, finally, some indications are given as an updated guide for the management of radiation oncology patients with pacemakers or cardioverter defibrillators implanted. (Author)

  17. Performance of the 2015 International Task Force Consensus Statement Risk Stratification Algorithm for Implantable Cardioverter-Defibrillator Placement in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy.

    Science.gov (United States)

    Orgeron, Gabriela M; Te Riele, Anneline; Tichnell, Crystal; Wang, Weijia; Murray, Brittney; Bhonsale, Aditya; Judge, Daniel P; Kamel, Ihab R; Zimmerman, Stephan L; Tandri, Harikrishna; Calkins, Hugh; James, Cynthia A

    2018-02-01

    Ventricular arrhythmias are a feared complication of arrhythmogenic right ventricular dysplasia/cardiomyopathy. In 2015, an International Task Force Consensus Statement proposed a risk stratification algorithm for implantable cardioverter-defibrillator placement in arrhythmogenic right ventricular dysplasia/cardiomyopathy. To evaluate performance of the algorithm, 365 arrhythmogenic right ventricular dysplasia/cardiomyopathy patients were classified as having a Class I, IIa, IIb, or III indication per the algorithm at baseline. Survival free from sustained ventricular arrhythmia (VT/VF) in follow-up was the primary outcome. Incidence of ventricular fibrillation/flutter cycle length the algorithm appropriately differentiated risk of VT/VF, incidence of VT/VF was underestimated (observed versus expected: 29.6 [95% confidence interval, 25.2-34.0] versus >10%/year Class I; 15.5 [confidence interval 11.1-21.6] versus 1% to 10%/year Class IIa). In addition, the algorithm did not differentiate survival free from ventricular fibrillation/flutter between Class I and IIa patients ( P =0.97) or for VT/VF in Class I and IIa primary prevention patients ( P =0.22). Adding Holter results (the algorithm differentiates arrhythmic risk well overall, it did not distinguish ventricular fibrillation/flutter risks of patients with Class I and IIa implantable cardioverter-defibrillator indications. Limited differentiation was seen for primary prevention cases. As these are vital uncertainties in clinical decision-making, refinements to the algorithm are suggested prior to implementation. © 2018 American Heart Association, Inc.

  18. [The daily experience of the patient with an implantable cardioverter defibrillator].

    Science.gov (United States)

    Palacios-Ceña, Domingo; Alonso-Blanco, Cristina; Cachón-Pérez, José Miguel; Alvarez-López, Cristina

    2010-01-01

    To describe the daily experience of patients with an automatic defibrillator (AD) implant and the adaptive changes of the patient. Qualitative and phenomenological research. Collection of data through; initially unstructured interview with half of the informants, semi-structured interviews through an open questions guide after the initial unstructured interviews and use of personal narratives of the informants. Analysis of the data using the Van Manen proposal. We analysed the interviews of 10 participants. We collected socio-demographic variables and identified the following themes, which respond to the question "How is life with an AD": It is life "with the two sides of the coin," living in constant wait and uncertainty, accepting change, developing adaptation strategies, renegotiating relationships and sexuality and it is to live transformed. The results of this study can be integrated into nurse clinical practice in areas such as valuation after discharge, changes in habits, control of treatment, notification of shocks, masking detection of symptoms and strategies that can jeopardise the bearer. Research needs to be developed that looks closer into the influence of other technological devices in people. Copyright 2009 Elsevier España, S.L. All rights reserved.

  19. Methodological limitations of psychosocial interventions in patients with an implantable cardioverter-defibrillator (ICD A systematic review

    Directory of Open Access Journals (Sweden)

    Ockene Ira S

    2009-12-01

    Full Text Available Abstract Background Despite the potentially life-saving benefits of the implantable cardioverter-defibrillator (ICD, a significant group of patients experiences emotional distress after ICD implantation. Different psychosocial interventions have been employed to improve this condition, but previous reviews have suggested that methodological issues may limit the validity of such interventions. Aim: To review the methodology of previously published studies of psychosocial interventions in ICD patients, according to CONSORT statement guidelines for non-pharmacological interventions, and provide recommendations for future research. Methods We electronically searched the PubMed, PsycInfo and Cochrane databases. To be included, studies needed to be published in a peer-reviewed journal between 1980 and 2008, to involve a human population aged 18+ years and to have an experimental design. Results Twelve studies met the eligibility criteria. Samples were generally small. Interventions were very heterogeneous; most studies used cognitive behavioural therapy (CBT and exercise programs either as unique interventions or as part of a multi-component program. Overall, studies showed a favourable effect on anxiety (6/9 and depression (4/8. CBT appeared to be the most effective intervention. There was no effect on the number of shocks and arrhythmic events, probably because studies were not powered to detect such an effect. Physical functioning improved in the three studies evaluating this outcome. Lack of information about the indication for ICD implantation (primary vs. secondary prevention, limited or no information regarding use of anti-arrhythmic (9/12 and psychotropic (10/12 treatment, lack of assessments of providers' treatment fidelity (12/12 and patients' adherence to the intervention (11/12 were the most common methodological limitations. Conclusions Overall, this review supports preliminary evidence of a positive effect of psychosocial interventions

  20. Evaluation of acute cardiac and chest wall damage after shocks with a subcutaneous implantable cardioverter defibrillator in Swine.

    Science.gov (United States)

    Killingsworth, Cheryl R; Melnick, Sharon B; Litovsky, Silvio H; Ideker, Raymond E; Walcott, Gregory P

    2013-10-01

    A subcutaneous implantable cardioverter defibrillator (S-ICD) could ease placement and reduce complications of transvenous ICDs, but requires more energy than transvenous ICDs. Therefore we assessed cardiac and chest wall damage caused by the maximum energy shocks delivered by both types of clinical devices. During sinus rhythm, anesthetized pigs (38 ± 6 kg) received an S-ICD (n = 4) and five 80-Joule (J) shocks, or a transvenous ICD (control, n = 4) and five 35-J shocks. An inactive S-ICD electrode was implanted into the same control pigs to study implant trauma. All animals survived 24 hours. Troponin I and creatine kinase muscle isoenzyme (CK-MM) were measured as indicators of myocardial and skeletal muscle injury. Histopathological injury of heart, lungs, and chest wall was assessed using semiquantitative scoring. Troponin I was significantly elevated at 4 hours and 24 hours (22.6 ± 16.3 ng/mL and 3.1 ± 1.3 ng/mL; baseline 0.07 ± 0.09 ng/mL) in control pigs but not in S-ICD pigs (0.12 ± 0.11 ng/mL and 0.13 ± 0.13 ng/mL; baseline 0.06 ± 0.03 ng/mL). CK-MM was significantly elevated in S-ICD pigs after shocks (6,544 ± 1,496 U/L and 9,705 ± 6,240 U/L; baseline 704 ± 398 U/L) but not in controls. Electrocardiogram changes occurred postshock in controls but not in S-ICD pigs. The myocardium and lungs were histologically normal in both groups. Subcutaneous injury was greater in S-ICD compared to controls. Although CK-MM suggested more skeletal muscle injury in S-ICD pigs, significant cardiac, lung, and chest wall histopathological changes were not detected in either group. Troponin I data indicate significantly less cardiac injury from 80-J S-ICD shocks than 35-J transvenous shocks. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

  1. Evaluation of acute cardiac and chest wall damage after shocks with a subcutaneous implantable cardioverter-defibrillator in swine

    Science.gov (United States)

    KILLINGSWORTH, CHERYL R.; MELNICK, SHARON B.; LITOVSKY, SILVIO H.; IDEKER, RAYMOND E.; WALCOTT, GREGORY P.

    2013-01-01

    Background A subcutaneous implantable cardioverter defibrillator (S-ICD) could ease placement and reduce complications of transvenous ICDs, but requires more energy than transvenous ICDs. Therefore we assessed cardiac and chest wall damage caused by the maximum energy shocks delivered by both types of clinical devices. Methods During sinus rhythm, anesthetized pigs (38±6 kg) received an S-ICD (n = 4) and five 80-Joule (J) shocks, or a transvenous ICD (control, n = 4) and five 35-J shocks. An inactive S-ICD electrode was implanted into the same control pigs to study implant trauma. All animals survived 24-hours. Troponin I and creatine kinase muscle isoenzyme (CK-MM) were measured as indicators of myocardial and skeletal muscle injury. Histopathological injury of heart, lungs, and chest wall was assessed using semi-quantitative scoring. Results Troponin I was significantly elevated at 4- and 24-hours (22.6±16.3 and 3.1±1.3 ng/ml; baseline 0.07±0.09 ng/ml) in control pigs but not in S-ICD pigs (0.12±0.11 and 0.13±0.13 ng/ml; baseline 0.06±0.03 ng/ml). CK-MM was significantly elevated in S-ICD pigs after shocks (6544±1496 and 9705±6240 U/L; baseline 704±398 U/L) but not in controls. ECG changes occurred post-shock in controls but not in S-ICD pigs. The myocardium and lungs were histologically normal in both groups. Subcutaneous injury was greater in S-ICD compared to controls. Conclusion Although CK-MM suggested more skeletal muscle injury in S-ICD pigs, significant cardiac, lung, and chest wall histopathological changes were not detected in either group. Troponin I data indicate significantly less cardiac injury from 80-J S-ICD shocks than 35-J transvenous shocks. PMID:23713608

  2. The healthcare utilization and cost of treating patients experiencing inappropriate implantable cardioverter defibrillator shocks: a propensity score study.

    Science.gov (United States)

    Bhavnani, Sanjeev P; Giedrimiene, Dalia; Coleman, Craig I; Guertin, Danette; Azeem, Meena; Kluger, Jeffrey

    2014-10-01

    Inappropriate shocks (IASs) from implantable cardioverter defibrillators (ICDs) are associated with decreased quality of life, but whether they increase healthcare utilization and treatment costs is unknown. We sought to determine the impact of IASs on subsequent healthcare utilization and treatment costs. We conducted a case-control analysis of ICD patients at a single institution from 1997 to 2010 and who had ≥12 months of post-ICD implant follow-up. Cases included all patients experiencing an IAS during the first 12 months after implantation. Eligible control patients did not receive a shock of any kind during the 12 months after implantation. Propensity scores based on 36 covariates (area under curve = 0.78) were used to match cases to controls. We compared the rate (occurrences/person year [PY]) of healthcare utilization immediately following IAS to the end of the 12-month follow-up period to the rate in the no-shock group over 12 months of follow-up. We also compared 12-month postimplant treatment (outpatient clinic, emergency room, and hospitalization) costs in both groups. A total of 76 patients experiencing ≥1 IAS during the first 12 months after implant (contributing 48 PYs) were matched to 76 no-shock patients (contributing 76 PYs). Cardiovascular (CV)-related clinic visit and hospitalization rates were increased following an IAS compared to those not receiving a shock (4.0 vs 3.3 and 0.7 vs 0.5, respectively, P = 0.02 for both). CV-related emergency room visitation (0.15 vs 0.08) rates were also numerically higher following an IAS, but did not reach statistical significance (P = 0.26). Patients experiencing an IAS accrued greater treatment costs during the 12 months postimplant compared to no-shock patients ($13,973 ± $46,345 vs $6,790 ± $19,091, P = 0.001). Recipients of IAS utilize the healthcare system more frequently following an IAS than patients not experiencing a shock. This increased utilization results in higher costs of treating IAS

  3. Nurse- and peer-led self-management programme for patients with an implantable cardioverter defibrillator; a feasibility study

    Directory of Open Access Journals (Sweden)

    van Eijk Jacques

    2007-09-01

    Full Text Available Abstract Background The prevalence of cardiovascular disease is increasing. Improved treatment options increase survival after an acute myocardial infarction or sudden cardiac arrest, although patients often have difficulty adjusting and regaining control in daily life. In particular, patients who received an implantable cardioverter defibrillator (ICD experience physical and psychological problems. Interventions to enhance perceived control and acceptance of the device are therefore necessary. This paper describes a small-scale study to explore the feasibility and the possible benefits of a structured nurse- and peer-led self-management programme ('Chronic Disease Self-Management Program' – CDSMP among ICD patients. Methods Ten male ICD patients (mean age = 65.5 years participated in a group programme, consisting of six sessions, led by a team consisting of a nurse specialist and a patient with cardiovascular disease. Programme feasibility was evaluated among patients and leaders by measuring performance of the intervention according to protocol, attendance and adherence of the participating ICD patients, and patients' and leaders' opinions about the programme. In addition, before and directly after attending the intervention, programme benefits (e.g. perceived control, symptoms of anxiety and depression, and quality of life were assessed. Results The programme was conducted largely according to protocol. Eight patients attended at least four sessions, and adherence ranged from good to very good. On average, the patients reported to have benefited very much from the programme, which they gave an overall report mark of 8.4. The leaders considered the programme feasible as well. Furthermore, improvements were identified for general self-efficacy expectancies, symptoms of anxiety, physical functioning, social functioning, role limitations due to physical problems, and pain. Conclusion This study suggests that a self-management programme led by a

  4. A clinical example of extreme dose exposure for an implanted cardioverter-defibrillator. Beyond the DEGRO guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hristova, Yoana; Koehn, Janett; Preuss, Stefanie [Johann Wolfgang Goethe University Frankfurt, Department of Radiation Oncology, University Hospital, Frankfurt (Germany); Roedel, Claus; Balermpas, Panagiotis [Johann Wolfgang Goethe University Frankfurt, Department of Radiation Oncology, University Hospital, Frankfurt (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); German Cancer Consortium (DKTK), Frankfurt am Main (Germany)

    2017-09-15

    Considering that the number of malignant diseases in patients over 65 years of age is increasing, it often occurs that patients who carry a cardiac implanted electronic device must undergo radiotherapy. Ionizing radiation can disturb the function of the implantable cardioverter-defibrillator (ICD). As a result of this, an update of the DEGRO/DKG guidelines for radiotherapy of this patient group has been published. We report the case of a patient with an ICD and T-lymphoblastic lymphoma with cardiac involvement, who received i.a. a total body irradiation with 8 Gy followed by a consolidating radiotherapy of the pericardium with 14 Gy as well as additional radiotherapy courses after consecutive recurrences. For the purposes of the treatment, the antitachyarrhythmia (ATA) therapy was deactivated and temporarily replaced through a life vest. According to the current DEGRO guidelines for irradiation of patients with cardiac implanted electronic devices, a categorization of the patient in the ''high-risk'' group was made. Furthermore, regular telemetric checks of the ICD device were performed before and after treatment. Despite unavailable declaration of the manufacturer regarding the cumulative tolerable dose and DEGRO recommendation for a cumulative dose <2 Gy, the aftercare was unproblematic and normal values were assessed for all relevant ICD parameters, despite a cumulative dose >10 Gy in the device. This case shows that if the cardiac implanted electronic devices are not directly irradiated und the energy used is reduced to 6 MV, irradiation-induced damage is less likely and can possibly be prevented. (orig.) [German] Vor dem Hintergrund der steigenden Zahl von Krebserkrankungen bei Patienten ueber 65 Jahren kommt es haeufig vor, dass sich Patienten mit einem kardialen implantierten elektronischen Geraet einer Strahlentherapie unterziehen muessen. Ionisierende Strahlung kann die Funktion des implantierbaren Kardioverter-Defibrillators (ICD

  5. Results of ENHANCED Implantable Cardioverter Defibrillator Programming to Reduce Therapies and Improve Quality of Life (from the ENHANCED-ICD Study)

    DEFF Research Database (Denmark)

    Mastenbroek, Mirjam H.; Pedersen, Susanne S.; van der Tweel, Ingeborg

    2016-01-01

    -reported outcomes. The "ENHANCED Implantable Cardioverter Defibrillator programming to reduce therapies and improve quality of life" study (ENHANCED-ICD study) was a prospective, safety-monitoring study enrolling 60 primary and secondary prevention patients at the University Medical Center Utrecht. Patients...... programming strategy, unnecessary ICD therapy was prevented in 10% of ENHANCED-ICD patients during a median follow-up period of 1.3 years. With respect to patient-reported outcomes, levels of distress were highest and perceived health status lowest at the time of implantation, which both gradually improved...... during follow-up. In conclusion, the ENHANCED-ICD study demonstrates that programming a NID 60/80 for VT/VF detection is safe for ICD patients and does not negatively impact their quality of life....

  6. [Nurses and doctors in the management of arrhytmic complications: the case of electric storm in patients with an implantable cardioverter defibrillator].

    Science.gov (United States)

    Plebani, Laura; Occhetta, Eraldo

    2006-01-01

    The evolution of arrhythmologic technology introduced new therapeutic opportunities for cardiology patients. Competence, continuity of care, integration and collaboration between medical doctors and nurses allow a safe management of short and long term complications. A typical example of a new arrhythmic complication is the "electrical storm" or "arrhythmic warm up" in patients implanted with a cardioverter-defibrillator (ICD). The definition and epidemiology of the electrical storm stress the relevance of this clinical situation; its dramatic emergency involves several aspects of nursing care, clinical, prognostic, ethical and deontological. The definition and implementation of an integrated protocol for the treatment of this condition is described and ethical and unresolved questions are rised. One of these problems is the recommendation to offer the patient the opportunity to receive information about the option of inactivating the ICD.

  7. A comparison of the health status and psychological distress of partners of patients with a left ventricular assist device versus an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Brouwers, Corline; Caliskan, Kadir; de Jonge, Nicolaas

    2014-01-01

    (F = 10.71, p = .001) but poorer mental health status (F = 14.82, p depression scores compared to ICD partners (F = 3.68, p = .05) at 6 months follow-up, also in adjusted analyses. There was no significant difference between groups on anxiety. CONCLUSION: Caregivers of LVAD......OBJECTIVE: To examine if the caregiving for patients with a left ventricular assist device (LVAD) is related to a poorer health status and more distress compared to patients with an implantable cardioverter defibrillator (ICD). BACKGROUND: Partners distress may influence patient outcomes...... and is therefore an important aspect in the care of LVAD and ICD patients. METHODS: Multi-center prospective observational study with 6 months follow-up of 33 LVAD partners (27% men; mean age = 54 ± 10 years) and 414 ICD partners (22% men; mean age = 60 ± 12 years). RESULTS: LVAD partners reported better physical...

  8. In vitro assessment of the immunity of implantable cardioverter-defibrillators to magnetic fields of 50/60 Hz.

    Science.gov (United States)

    Katrib, J; Nadi, M; Kourtiche, D; Magne, I; Schmitt, P; Souques, M; Roth, P

    2013-10-01

    Public concern for the compatibility of electromagnetic (EM) sources with active implantable medical devices (AIMD) has prompted the development of new systems that can perform accurate exposure studies. EM field interference with active cardiac implants (e.g. implantable cardioverter-defibrillators (ICDs)) can be critical. This paper describes a magnetic field (MF) exposure system and the method developed for testing the immunity of ICD to continuous-wave MFs. The MFs were created by Helmholtz coils, housed in a Faraday cage. The coils were able to produce highly uniform MFs up to 4000 µT at 50 Hz and 3900 µT at 60 Hz, within the test space. Four ICDs were tested. No dysfunctions were found in the generated MFs. These results confirm that the tested ICDs were immune to low frequency MFs.

  9. Is modification of the VVI backup mode in implantable cardioverter-defibrillators from St Jude medical required due to increased risk of inappropriate shocks?

    DEFF Research Database (Denmark)

    Philbert, Berit Thornvig; Tfelt-Hansen, Jacob; Jacobsen, Peter K

    2017-01-01

    Inappropriate implantable cardioverter-defibrillator (ICD) shock therapy is painful, stressful, and typically occurs unexpected in conscious patients and may be related to a less favourable prognosis. In our institution, we have observed four cases of multiple inappropriate ICD shocks during reset...... a ventricular fibrillation (VF) zone starting at 146 b.p.m., with shock therapy only and changes in sensitivity settings making the ICD more sensitive. In all cases, the reason for the multiple inappropriate shocks was that the VF zone was reached due to exercise-induced sinus tachycardia or due to oversensing...... during sinus rhythm. The VVI backup mode has to balance between protection from failure of ICD therapy during life-threatening ventricular arrhythmias and from inappropriate shocks. It seems the non-programmable parameters in VVI backup mode of St Jude Medical ICDs carry an unacceptable high risk...

  10. Beta-blocker therapy is not associated with symptoms of depression and anxiety in patients receiving an implantable cardioverter-defibrillator.

    Science.gov (United States)

    Hoogwegt, Madelein T; Kupper, Nina; Theuns, Dominic A M J; Jordaens, Luc; Pedersen, Susanne S

    2012-01-01

    Beta-blockers are frequently prescribed to implantable cardioverter-defibrillator (ICD) patients. Beta-blocker therapy has been proposed to induce emotional distress such as depression and anxiety, but a paucity of studies has examined the relationship between beta-blockers and distress. We investigated the association between beta-blocker therapy, including type and dosage, and symptoms of anxiety and depression in a consecutive cohort of patients receiving an ICD. Between 2003 and 2010, 448 consecutively implanted ICD patients were enrolled in the prospective Mood and personality as precipitants of arrhythmia in patients with an Implantable cardioverter Defibrillator: A prospective Study (MIDAS), of which 429 completed the Hospital Anxiety and Depression Scale (HADS) and the ICD Patient Concerns questionnaire (ICDC) at baseline. Eighty per cent of all patients received beta-blocker therapy. In univariate analysis, beta-blocker therapy was not significantly associated with symptoms of anxiety, depression, and ICD concerns (β = -0.030, β = 0.007, and β = -0.045, respectively; all P's >0.36). Type of beta-blocker showed a trend towards significance for mean levels of ICD concerns (P = 0.09). No association was found between dosage and emotional distress (all P's >0.21). After adjustment for relevant clinical and demographic variables, the association of beta-blocker therapy and symptoms of anxiety, depression, and ICD concerns remained non-significant (β = 0.009, β = 0.037, and β = 0.019, respectively; all P's >0.47). In patients receiving an ICD, beta-blocker therapy was not associated with symptoms of anxiety, depression, and ICD concerns. Research is warranted that further elucidates the link between beta-blocker therapy and emotional distress in this vulnerable patient group.

  11. Implantable Cardioverter Defibrillator

    Science.gov (United States)

    ... interfere with an ICD include: Cell phones and MP3 players (for example, iPods) Household appliances, such as ... experts recommend not putting your cell phone or MP3 player in a shirt pocket over your ICD ( ...

  12. Cost-Effectiveness of Adding Cardiac Resynchronization Therapy to an Implantable Cardioverter-Defibrillator Among Patients With Mild Heart Failure

    DEFF Research Database (Denmark)

    Woo, Christopher Y; Strandberg, Erika J; Schmiegelow, Michelle D

    2015-01-01

    -defibrillator (ICD) alone among patients with left ventricular systolic dysfunction, prolonged intraventricular conduction, and mild heart failure. DESIGN: Markov decision model. DATA SOURCES: Clinical trials, clinical registries, claims data from Centers for Medicare & Medicaid Services, and Centers for Disease...

  13. Catheter ablation for the treatment of electrical storm in patients with implantable cardioverter-defibrillators: short- and long-term outcomes in a prospective single-center study.

    Science.gov (United States)

    Carbucicchio, Corrado; Santamaria, Matteo; Trevisi, Nicola; Maccabelli, Giuseppe; Giraldi, Francesco; Fassini, Gaetano; Riva, Stefania; Moltrasio, Massimo; Cireddu, Manuela; Veglia, Fabrizio; Della Bella, Paolo

    2008-01-29

    Electrical storm (ES) caused by recurrent episodes of ventricular tachycardia (VT) can cause sudden death in patients with implantable cardioverter-defibrillators and adversely affects prognosis in survivors. Catheter ablation has been proposed for treating ES, but its long-term effect in a large population has never been verified. Ninety-five consecutive patients with coronary artery disease (72 patients), idiopathic dilated cardiomyopathy (10 patients), and arrhythmogenic right ventricular dysplasia/cardiomyopathy (13 patients) undergoing catheter ablation for drug-refractory ES were prospectively evaluated. Short-term efficacy was defined by a complete protocol of programmed electric stimulation and by in-hospital outcome; long-term analysis addressed ES recurrence, cardiac mortality, and VT recurrence. Pleomorphic/nontolerated VTs required electroanatomic and noncontact mapping in 48 and 22 patients, respectively, and percutaneous cardiopulmonary support in 10 patients. An epicardial approach was used in 10 patients. After 1 to 3 procedures, induction of any clinical VT(s) by programmed electrical stimulation was prevented in 85 patients (89%). ES was acutely suppressed in all patients; a minimum period of 7 days with stable rhythm was required before hospital discharge. At a median follow-up of 22 months (range, 1 to 43 months), 87 patients (92%) were free of ES and 63 patients (66%) were free of VT recurrence. Eight of 10 patients with persistent inducibility of clinical VT(s) had ES recurrence; 4 of them died suddenly despite appropriate implantable cardioverter-defibrillator intervention. All together, 11 of 95 patients (12%) died of cardiac-related reasons. In the group of patients presenting with all clinical VTs acutely abolished, no ES recurrence was documented, and cardiac mortality was significantly lower compared with the group of patients showing > or = 1 clinical VT still inducible after catheter ablation. Advanced strategies of catheter ablation

  14. Unmappable ventricular tachycardia after an old myocardial infarction. Long-term results of substrate modification in patients with an implantable cardioverter defibrillator.

    Science.gov (United States)

    Alzand, B S N; Timmermans, C C M M; Wellens, H J J; Dennert, R; Philippens, S A M; Portegijs, P J M; Rodriguez, L M

    2011-08-01

    The frequent occurrence of ventricular tachycardia can create a serious problem in patients with an implantable cardioverter defibrillator. We assessed the long-term efficacy of catheter-based substrate modification using the voltage mapping technique of infarct-related ventricular tachycardia and recurrent device therapy. The study population consisted of 27 consecutive patients (age 68 ± 8 years, 25 men, mean left ventricular ejection fraction 31 ± 9%) with an old myocardial infarction and multiple and/or hemodynamically not tolerated ventricular tachycardia necessitating repeated device therapy. A total of 31 substrate modification procedures were performed using the three-dimensional electroanatomical mapping system. Patients were followed up for a median of 23.5 (interquartile range 6.5-53.2) months before and 37.8 (interquartile range 11.7-71.8) months after ablation. Antiarrhythmic drugs were not changed after the procedure, and were stopped 6 to 9 months after the procedure in patients who did not show ventricular tachycardia recurrence. Median ventricular tachycardias were 1.6 (interquartile range 0.7-6.7) per month before and 0.2 (interquartile range 0.00-1.3) per month after ablation (P = 0.006). Nine ventricular fibrillation episodes were registered in seven patients before and two after ablation (P = 0.025). Median antitachycardia pacing decreased from 1.6 (interquartile range 0.01-5.5) per month before to 0.18 (interquartile range 0.00-1.6) per month after ablation (P = 0.069). Median number of shocks decreased from 0.19 (interquartile range 0.04-0.81) per month before to 0.00 (interquartile range 0.00-0.09) per month after ablation (P = 0.001). One patient had a transient ischemic attack during the procedure, and another developed pericarditis. Nine patients died during follow-up, eight patients due to heart failure and one patient during valve surgery. Catheter-based substrate modification using voltage mapping results in a long-lasting reduction

  15. [Safety of cardiac pacemakers and implantable cardioverter-defibrillators in magnetic resonance imaging. Assessment of the aggregate function at 1.5 tesla].

    Science.gov (United States)

    Nordbeck, P; Bauer, W R

    2008-03-01

    Magnetic resonance imaging (MRI) is increasingly used in patients, but it is contraindicated in those with cardiac pacemakers (CP) or implantable cardioverter defibrillators (ICD). This study examined circumstances in which potentially life-threatening arrhythmias may be triggered in patients with CP undergoing MRI and whether these problems can be avoided by reprogramming of these devices. Eight CP and seven ICDs were investigated in a phantom at 1.5 tesla (experimental and imaging sequences). A decrease in battery voltage was found in four CP after MRI (indication for elective replacement). Additionally, three showed changes in programming (resets). Analogous changes did not appear in the tested ICDs, but periods of tachycardia were recorded in all types of devices during MRI depending on the pulse sequence employed. MRI-related electromagnetic fields as used in routine MRI can induce severe pacemaker device malfunctions. Device programming approaches are unreliable for prevention of patient hazards, as programming changes or resets are one of the primary malfunctions during MRI.

  16. Importance of beta-blocker dose in prevention of ventricular tachyarrhythmias, heart failure hospitalizations, and death in primary prevention implantable cardioverter-defibrillator recipients

    DEFF Research Database (Denmark)

    Ruwald, A C; Gislason, G H; Vinther, M

    2018-01-01

    Aims: There is a paucity of studies investigating a dose-dependent association between beta-blocker therapy and risk of outcome. In a nationwide cohort of primary prevention implantable cardioverter-defibrillator (ICD) patients, we aimed to investigate the dose-dependent association between beta-blocker...... therapy and risk of ventricular tachyarrhythmias (VT/VF), heart failure (HF) hospitalizations, and death. Methods and results: Information on ICD implantation, endpoints, comorbidities, beta-blocker usage, type, and dose were obtained through Danish nationwide registers. The two major beta-blockers...... carvedilol and metoprolol were examined in three dose levels; low (metoprolol ≤ 25 mg; carvedilol ≤ 12.5 mg), intermediate (metoprolol 26-199 mg; carvedilol 12.6-49.9 mg), and high (metoprolol ≥ 200 mg; carvedilol ≥ 50 mg). Time to events was investigated utilizing multivariate Cox models with beta-blocker...

  17. Radiation therapy in patients with cardiac pacemakers or implantable cardioverter defibrillators. Interdisciplinary safety recommendations; Strahlentherapie bei Patienten mit Herzschrittmachern oder implantierbaren Kardioverter-Defibrillatoren. Interdisziplinaere Sicherheitsempfehlungen

    Energy Technology Data Exchange (ETDEWEB)

    Dorenkamp, M.; Haverkmap, W.; Roser, M. [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum (Germany). Medizinische Klinik mit Schwerpunkt Kardiologie; Stromberger, C.; Wust, P. [Charite Universitaetsmedizin Berlin (Germany). Klinik fuer Radioonkologie und Strahlentherapie; Heymann, C. von [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum (Germany). Klinik fuer Anaesthesiologie mit Schwerpunkt operative Intensivmedizin

    2013-01-15

    Background: With increasing numbers of implanted pacemakers and implantable cardioverter defibrillators (ICD) and a rising incidence of malignant tumors, there is a growing probability of radiation-mediated device dysfunction. The only guidelines for the management of patients with cardiac pacemakers in the case of radiation therapy were published in 1994 and have not been updated since then. Based on the current evidence and modern device technology, the present paper aims to develop contemporary and interdisciplinary safety recommendations for the minimization of patient risk. Methods and results: A systematic literature research was carried out including the most relevant medical electronic databases. The search yielded 147 articles published between 1994 and 2012 of which 45 met the selection criteria and of these studies 34 presented primary data (9 in vitro and 25 in vivo studies). The impact of ionizing radiation varied significantly between implanted devices and ranged from no functional changes to complete loss of function. Important device dysfunctions included changes in sensing capability, altered pacing pulses or rate, changed or disabled tachyarrhythmia ICD therapies, early battery depletion and loss of telemetry. Modern pacemakers and ICDs are more sensitive to radiation than older models. Potentially life-threatening complications were observed after exposure of the pulse generator to comparatively low radiation doses (0.11 Gy). Conclusions: Practical recommendations for patient management and safety are presented that can be readily adopted by any institution carrying out radiation therapy. (orig.)

  18. Appropriate evaluation and treatment of heart failure patients after implantable cardioverter-defibrillator discharge: time to go beyond the initial shock.

    Science.gov (United States)

    Mishkin, Joseph D; Saxonhouse, Sherry J; Woo, Gregory W; Burkart, Thomas A; Miles, William M; Conti, Jamie B; Schofield, Richard S; Sears, Samuel F; Aranda, Juan M

    2009-11-24

    Multiple clinical trials support the use of implantable cardioverter-defibrillators (ICDs) for prevention of sudden cardiac death in patients with heart failure (HF). Unfortunately, several complicating issues have arisen from the universal use of ICDs in HF patients. An estimated 20% to 35% of HF patients who receive an ICD for primary prevention will experience an appropriate shock within 1 to 3 years of implant, and one-third of patients will experience an inappropriate shock. An ICD shock is associated with a 2- to 5-fold increase in mortality, with the most common cause being progressive HF. The median time from initial ICD shock to death ranges from 168 to 294 days depending on HF etiology and the appropriateness of the ICD therapy. Despite this prognosis, current guidelines do not provide a clear stepwise approach to managing these high-risk patients. An ICD shock increases HF event risk and should trigger a thorough evaluation to determine the etiology of the shock and guide subsequent therapeutic interventions. Several combinations of pharmacologic and device-based interventions such as adding amiodarone to baseline beta-blocker therapy, adjusting ICD sensitivity, and employing antitachycardia pacing may reduce future appropriate and inappropriate shocks. Aggressive HF surveillance and management is required after an ICD shock, as the risk of sudden cardiac death is transformed to an increased HF event risk.

  19. Educational and psychological interventions to improve outcomes for recipients of implantable cardioverter defibrillators and their families: a scientific statement from the American Heart Association.

    Science.gov (United States)

    Dunbar, Sandra B; Dougherty, Cynthia M; Sears, Samuel F; Carroll, Diane L; Goldstein, Nathan E; Mark, Daniel B; McDaniel, George; Pressler, Susan J; Schron, Eleanor; Wang, Paul; Zeigler, Vicki L

    2012-10-23

    Significant mortality benefits have been documented in recipients of implantable cardioverter defibrillators (ICDs); however, the psychosocial distress created by the underlying arrhythmia and its potential treatments in patients and family members may be underappreciated by clinical care teams. The disentanglement of cardiac disease and device-related concerns is difficult. The majority of ICD patients and families successfully adjust to the ICD, but optimal care pathways may require additional psychosocial attention to all ICD patients and particularly those experiencing psychosocial distress. This state-of-the-science report was developed on the basis of an analysis and critique of existing science to (1) describe the psychological and quality-of-life outcomes after receipt of an ICD and describe related factors, such as patient characteristics; (2) describe the concerns and educational/informational needs of ICD patients and their family members; (3) outline the evidence that supports interventions for improving educational and psychological outcomes for ICD patients; (4) provide recommendations for clinical approaches for improving patient outcomes; and (5) identify priorities for future research in this area. The ultimate goal of this statement is to improve the precision of identification and care of psychosocial distress in ICD patients to maximize the derived benefit of the ICD.

  20. Effect of psycho-educational interventions on quality of life in patients with implantable cardioverter defibrillators: a meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Kao, Chi-Wen; Chen, Miao-Yi; Chen, Ting-Yu; Lin, Pai-Hui

    2016-09-30

    Implantable cardioverter defibrillators (ICD) were developed for primary and secondary prevention of sudden cardiac death. However, ICD recipients' mortality is significantly predicted by their quality of life (QOL). The aim of this meta-analysis was to evaluate the effects of psycho-educational interventions on QOL in patients with ICDs. We systematically searched PubMed, Medline, Cochrane Library, and CINAHL through April 2015 and references of relevant articles. Studies were reviewed if they met following criteria: (1) randomized controlled trial, (2) participants were adults with an ICD, and (3) data were sufficient to evaluate the effect of psychological or educational interventions on QOL measured by the SF-36 or SF-12. Studies were independently selected and their data were extracted by two reviewers. Study quality was evaluated using a modified Jadad scale. The meta-analysis was conducted using the Cochrane Collaboration's Review Manager Software Package (RevMan 5). Study heterogeneity was assessed by Q statistics and I 2 statistic. Depending on heterogeneity, data were pooled across trials using fixed-effect or random-effect modeling. Seven randomized controlled trials fulfilled the inclusion and exclusion criteria, and included 1017 participants. The psycho-educational interventions improved physical component summary (PCS) scores in the intervention groups more than in control groups (mean difference 2.08, 95 % CI 0.86 to 3.29, p educational interventions improved the physical component, but not the mental component of QOL in patients with ICDs.

  1. Design and Methods for a Pilot Study of a Phone-Delivered, Mindfulness-Based Intervention in Patients with Implantable Cardioverter Defibrillators

    Directory of Open Access Journals (Sweden)

    Elena Salmoirago-Blotcher

    2012-01-01

    Full Text Available Background. Meditation practices are associated with a reduction in adrenergic activity that may benefit patients with severe cardiac arrhythmias. This paper describes the design and methods of a pilot study testing the feasibility of a phone-delivered mindfulness-based intervention (MBI for treatment of anxiety in patients with implantable cardioverter defibrillators (ICDs. Design and Methods. Consecutive, clinically stable outpatients (n=52 will be screened for study eligibility within a month of an ICD-related procedure or ICD shock and will be randomly assigned to MBI or to usual care. MBI patients will receive eight weekly individual phone sessions based on two mindfulness practices (awareness of breath and body scan plus home practice with a CD for 20 minutes daily. Patients assigned to usual care will be offered the standard care planned by the hospital. Assessments will occur at baseline and at the completion of the intervention (between 9 and 12 weeks after randomization. The primary study outcome is feasibility; secondary outcomes include anxiety, mindfulness, and number of administered shocks during the intervention period. Conclusions. If proven feasible and effective, phone-delivered mindfulness-based interventions could improve psychological distress in ICD outpatients with serious cardiovascular conditions.

  2. Contemporary rates and outcomes of single- vs. dual-coil implantable cardioverter defibrillator lead implantation: data from the Israeli ICD Registry.

    Science.gov (United States)

    Leshem, Eran; Suleiman, Mahmoud; Laish-Farkash, Avishag; Konstantino, Yuval; Glikson, Michael; Barsheshet, Alon; Goldenberg, Ilan; Michowitz, Yoav

    2017-09-01

    Dual-coil leads were traditionally considered standard of care due to lower defibrillation thresholds (DFT). Higher complication rates during extraction with parallel progression in implantable cardioverter defibrillator (ICD) technology raised questions on dual coil necessity. Prior substudies found no significant outcome difference between dual and single coils, although using higher rates of DFT testing then currently practiced. We evaluated the temporal trends in implantation rates of single- vs. dual-coil leads and determined the associated adverse clinical outcomes, using a contemporary nation-wide ICD registry. Between July 2010 and March 2015, 6343 consecutive ICD (n = 3998) or CRT-D (n = 2345) implantation patients were prospectively enrolled in the Israeli ICD Registry. A follow-up of at least 1 year of 2285 patients was available for outcome analysis. The primary endpoint was all-cause mortality. Single-coil leads were implanted in 32% of our cohort, 36% among ICD recipients, and 26% among CRT-D recipients. Secondary prevention indication was associated with an increased rate of dual-coil implantation. A significant decline in dual-coil leads with reciprocal incline of single coils was observed, despite low rates of DFT testing (11.6%) during implantation, which also declined from 31 to 2%. In the multivariate Cox model analysis, dual- vs. single-coil lead implantation was not associated with an increased risk of mortality [hazard ratio (HR) = 1.23; P= 0.33], heart failure hospitalization (HR = 1.34; P=0.13), appropriate (HR = 1.25; P= 0.33), or inappropriate ICD therapy (HR = 2.07; P= 0.12). Real-life rates of single-coil lead implantation are rising while adding no additional risk. These results of single-coil safety are reassuring and obtained, despite low and contemporary rates of DFT testing. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  3. Identifying patients with less potential to benefit from implantable cardioverter-defibrillator therapy: comparison of the performance of four risk scoring systems.

    Science.gov (United States)

    Kaura, Amit; Sunderland, Nicholas; Kamdar, Ravi; Petzer, Edward; McDonagh, Theresa; Murgatroyd, Francis; Dhillon, Para; Scott, Paul

    2017-08-01

    Patients at high non-sudden cardiac death risk may gain no significant benefit from implantable cardioverter-defibrillator (ICD) therapy. A number of approaches have been proposed to identify these patients, including single clinical markers and more complex scoring systems. The aims of this study were to use the proposed scoring systems to (1) establish how many current ICD recipients may be too high risk to derive significant benefit from ICD therapy and (2) evaluate how well the scoring systems predict short-term mortality in an unselected ICD cohort. We performed a single-centre retrospective observational study of all new ICD implants over 5 years (2009-2013). We used four published scoring systems (Bilchick, Goldenberg, Kramer and Parkash) and serum urea to identify new ICD recipients whose short-term predicted mortality risk was high. We evaluated how well the scoring systems predicted death. Over 5 years, there were 406 new implants (79% male, mean age 70 (60-76), 58% primary prevention). During a follow-up of 936 ± 560 days, 96 patients died. Using the scoring systems, the proportion of ICD recipients predicted to be at high short-term mortality risk were 5.9% (Bilchick), 34.7% (Goldenberg), 7.4% (Kramer), 21.4% (Parkash) and 25% (urea, cut-off of >9.28 mM). All four risk scores predicted mortality (P systems, a significant proportion of current ICD recipients are at high short-term mortality risk. Although all four scoring systems predicted mortality during follow-up, none significantly outperformed serum urea.

  4. Cardiac sympathetic innervation assessed with (123)I-MIBG retains prognostic utility in diabetic patients with severe left ventricular dysfunction evaluated for primary prevention implantable cardioverter-defibrillator.

    Science.gov (United States)

    García-González, P; Fabregat-Andrés, Ó; Cozar-Santiago, P; Sánchez-Jurado, R; Estornell-Erill, J; Valle-Muñoz, A; Quesada-Dorador, A; Payá-Serrano, R; Ferrer-Rebolleda, J; Ridocci-Soriano, F

    2016-01-01

    Scintigraphy with iodine-123-metaiodobenzylguanidine ((123)I-MIBG) is a non-invasive tool for the assessment of cardiac sympathetic innervation (CSI) that has proven to be an independent predictor of survival. Recent studies have shown that diabetic patients with heart failure (HF) have a higher deterioration in CSI. It is unknown if (123)I-MIBG has the same predictive value for diabetic and non-diabetic patients with advanced HF. An analysis is performed to determine whether CSI with (123)I-MIBG retains prognostic utility in diabetic patients with HF, evaluated for a primary prevention implantable cardioverter-defibrillator (ICD). Seventy-eight consecutive HF patients (48 diabetic) evaluated for primary prevention ICD implantation were prospectively enrolled and underwent (123)I-MIBG to assess CSI (heart-to-mediastinum ratio - HMR). A Cox proportional hazards multivariate analysis was used to determine the influence of (123)I-MIBG images for prediction of cardiac events in both diabetic and non-diabetic patients. The primary end-point was a composite of arrhythmic event, cardiac death, or admission due to HF. During a mean follow-up of 19.5 [9.3-29.3] months, the primary end-point occurred in 24 (31%) patients. Late HMR was significantly lower in diabetic patients (1.30 vs. 1.41, p=0.014). Late HMR≤1.30 was an independent predictor of cardiac events in diabetic (hazard ratio 4.53; p=0.012) and non-diabetic patients (hazard ratio 12.31; p=0.023). Diabetic patients with HF evaluated for primary prevention ICD show a higher deterioration in CSI than non-diabetics; nevertheless (123)I-MIBG imaging retained prognostic utility for both diabetic and non-diabetic patients. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  5. Device orientation of a leadless pacemaker and subcutaneous implantable cardioverter-defibrillator in canine and human subjects and the effect on intrabody communication.

    Science.gov (United States)

    Quast, Anne-Floor B E; Tjong, Fleur V Y; Koop, Brendan E; Wilde, Arthur A M; Knops, Reinoud E; Burke, Martin C

    2018-02-14

    The development of communicating modular cardiac rhythm management systems relies on effective intrabody communication between a subcutaneous implantable cardioverter-defibrillator (S-ICD) and a leadless pacemaker (LP), using conducted communication. Communication success is affected by the LP and S-ICD orientation. This study is designed to evaluate the orientation of the LP and S-ICD in canine subjects and measure success and threshold of intrabody communication. To gain more human insights, we will explore device orientation in LP and S-ICD patients. Canine subjects implanted with a prototype S-ICD and LP (both Boston Scientific, MA, USA) with anterior-posterior fluoroscopy images were included in this analysis. For comparison, a retrospective analysis of human S-ICD and LP patients was performed. The angle of the long axis of the LP towards the vertical axis of 0°, and distance between the coil and LP were measured. Twenty-three canine subjects were analysed. Median angle of the LP was 29° and median distance of the S-ICD coil to LP was 0.8 cm. All canine subjects had successful communication. The median communicating threshold was 2.5 V. In the human retrospective analysis, 72 LP patients and 100 S-ICD patients were included. The mean angle of the LP was 56° and the median distance between the S-ICD coil and LP was 4.6 cm. Despite the less favourable LP orientation in canine subjects, all communication attempts were successful. In the human subjects, we observed a greater and in theory more favourable LP angle towards the communication vector. These data suggests suitability of human anatomy for conductive intrabody communication.

  6. Detection of atrial fibrillation and flutter by a dual-chamber implantable cardioverter-defibrillator. For the Worldwide Jewel AF Investigators.

    Science.gov (United States)

    Swerdlow, C D; Schsls, W; Dijkman, B; Jung, W; Sheth, N V; Olson, W H; Gunderson, B D

    2000-02-29

    To distinguish prolonged episodes of atrial fibrillation (AF) that require cardioversion from self-terminating episodes that do not, an atrial implantable cardioverter-defibrillator (ICD) must be able to detect AF continuously for extended periods. The ICD should discriminate between atrial tachycardia/flutter (AT), which may be terminated by antitachycardia pacing, and AF, which requires cardioversion. We studied 80 patients with AT/AF and ventricular arrhythmias who were treated with a new atrial/dual-chamber ICD. During a follow-up period lasting 6+/-2 months, we validated spontaneous, device-defined AT/AF episodes by stored electrograms in all patients. In 58 patients, we performed 80 Holter recordings with telemetered atrial electrograms, both to validate the continuous detection of AT/AF and to determine the sensitivity of the detection of AT/AF. Detection was appropriate in 98% of 132 AF episodes and 88% of 190 AT episodes (98% of 128 AT episodes with an atrial cycle length 1 hour, for a total of 2697 hours of continuous detection of AT/AF. During Holter monitoring, the sensitivity of the detection of AT/AF (116 hours) was 100%; the specificity of the detection of non-AT/AF rhythms (1290 hours) was 99.99%. Of 166 appropriate episodes detected as AT, 45% were terminated by antitachycardia pacing. A new ICD detects AT/AF accurately and continuously. Therapy may be programmed for long-duration AT/AF, with a low risk of underdetection. Discrimination of AT from AF permits successful pacing therapy for a significant fraction of AT.

  7. The Role of Implantable Cardioverter Defibrillators in Patients Bridged to Transplantation with a Continuous Flow Left Ventricular Assist Device: A Propensity Score Matched Analysis

    Science.gov (United States)

    Clerkin, Kevin J.; Topkara, Veli K.; Mancini, Donna M.; Yuzefpolskaya, Melana; Demmer, Ryan T.; Dizon, Jose M.; Takeda, Koji; Takayama, Hiroo; Naka, Yoshifumi; Colombo, Paolo C.; Garan, A. Reshad

    2016-01-01

    Background Implantable cardioverter defibrillators (ICD) provide a significant mortality benefit for appropriately selected patients with advanced heart failure. ICDs are associated with a mortality benefit when used in patients with a pulsatile left ventricular assist device (LVAD). However it is unclear whether patients with a continuous flow LVAD (CF-LVAD) derive the same benefit. This study sought to determine if the presence of an ICD provided a mortality benefit during CFLVAD support as a bridge to transplantation. Methods Patients were identified in the United Network for Organ Sharing (UNOS) registry that underwent LVAD implantation as bridge to transplantation from May 2004 and April 2014, with follow-up through June 2014. The primary outcome was freedom from death while on CF-LVAD support with adjustment for complications requiring UNOS listing status upgrade. Secondary endpoints included freedom from delisting while on CF-LVAD support and incidence of transplantation. Results 2,990 patients composed the study cohort and propensity score matching identified 1,012 patients with similar propensity scores. There was no difference in survival during device support between patients with and without an ICD (Hazard Ratio [HR] 1.20, 95% Confidence Interval [CI] 0.66-2.17, p=0.55). Adjusting for device complications requiring a UNOS listing status upgrade had minimal influence (HR 1.11, 95% CI 0.60-2.05, p=0.74). There was no increased risk of delisting due to being too sick for those with an ICD (HR 1.08, 95% CI 0.63-1.86, p=0.78). Likewise, the probability of transplantation was similar (HR 1.05, 95% CI 0.87-1.27, p=0.62). Conclusions Among patients bridged to transplantation with a CF-LVAD, the presence of an ICD did not reduce mortality. PMID:28089072

  8. The role of implantable cardioverter defibrillators in patients bridged to transplantation with a continuous-flow left ventricular assist device: A propensity score matched analysis.

    Science.gov (United States)

    Clerkin, Kevin J; Topkara, Veli K; Mancini, Donna M; Yuzefpolskaya, Melana; Demmer, Ryan T; Dizon, Jose M; Takeda, Koji; Takayama, Hiroo; Naka, Yoshifumi; Colombo, Paolo C; Garan, A Reshad

    2017-06-01

    Implantable cardioverter defibrillators (ICDs) provide a significant mortality benefit for appropriately selected patients with advanced heart failure. ICDs are associated with a mortality benefit when used in patients with a pulsatile left ventricular assist device (LVAD). It is unclear whether patients with a continuous-flow LVAD (CF-LVAD) derive the same benefit. We sought to determine if the presence of an ICD provided a mortality benefit during CF-LVAD support as a bridge to transplantation. Patients were identified in the United Network for Organ Sharing (UNOS) registry who underwent LVAD implantation as bridge to transplantation between May 2004 and April 2014, with follow-up through June 2014. Primary outcome was freedom from death while on CF-LVAD support with adjustment for complications requiring UNOS listing status upgrade. Secondary end-points included freedom from delisting while on CF-LVAD support and incidence of transplantation. The study cohort comprised 2,990 patients, and propensity score matching identified 1,012 patients with similar propensity scores. There was no difference in survival during device support between patients with and without an ICD (hazard ratio [HR] = 1.20; 95% confidence interval [CI], 0.66-2.17; p = 0.55). Adjusting for device complications requiring a UNOS listing status upgrade had minimal influence (HR = 1.11; 95% CI, 0.60-2.05; p = 0.74). There was no increased risk of delisting owing to being too sick for patients with an ICD (HR = 1.08; 95% CI, 0.63-1.86; p = 0.78). Likewise, the probability of transplantation was similar (HR = 1.05; 95% CI, 0.87-1.27; p = 0.62). Among patients bridged to transplantation with a CF-LVAD, the presence of an ICD did not reduce mortality. Copyright © 2017 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  9. Combined etiology of anaphylactic cardiogenic shock: Amiodarone, epinephrine, cardioverter defibrillator, left ventricular assist devices and the Kounis syndrome

    Directory of Open Access Journals (Sweden)

    Nicholas G Kounis

    2015-01-01

    Full Text Available Anaphylactic shock is a life-threatening condition which needs detailed and mediculous clinical assessment and thoughtful treatment. Several causes can join forces in order to degranulate mast cells. Amiodarone which is an iodine-containing highly lipophilic benzofuran can induce allergic reactions and anaphylactic shock in sensitized patients. Epinephrine is a life saving drug, but in sulfite allergic patients it should be given with caution due its metabisulfite preservative. Metals covering cardiac defibrillators and pacemakers can act as antigens attached to serum proteins and induce allergic reactions. In anaphylactic shock, myocardial involvement due to vasospasm-induced coronary blood flow reduction manifesting as Kounis syndrome should be always considered. Clinically, combined treatment targeting the primary cause of anaphylaxis together with protection of cardiac tissue seems to be of paramount importance.

  10. Polymorphisms associated with ventricular tachyarrhythmias: rationale, design, and endpoints of the 'diagnostic data influence on disease management and relation of genomics to ventricular tachyarrhythmias in implantable cardioverter/defibrillator patients (DISCOVERY)' study

    DEFF Research Database (Denmark)

    Wieneke, Heinrich; Spencker, Sebastian; Svendsen, Jesper Hastrup

    2010-01-01

    Implantable cardioverter-defibrillator (ICD) therapy is effective in primary and secondary prevention for patients who are at high risk of sudden cardiac death. However, the current risk stratification of patients who may benefit from this therapy is unsatisfactory. Single nucleotide polymorphism...... pathways will be investigated. As it is a diagnostic study, DISCOVERY will also investigate the impact of long-term device diagnostic data on the management of patients suffering from chronic cardiac disease as well as medical decisions made regarding their treatment.......Implantable cardioverter-defibrillator (ICD) therapy is effective in primary and secondary prevention for patients who are at high risk of sudden cardiac death. However, the current risk stratification of patients who may benefit from this therapy is unsatisfactory. Single nucleotide polymorphisms...... modulate the risk for arrhythmias and sudden cardiac death, and identification of common variants could help to better identify patients at risk. The DISCOVERY study is an interventional, longitudinal, prospective, multi-centre diagnostic study that will enrol 1287 patients in approximately 80 European...

  11. A Pregnancy with Severe Hypertrophic Obstructive Cardiomyopathy after Surgery for an Implantable Cardioverter Defibrillator: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Takashi Mitsui

    2016-01-01

    Full Text Available Hypertrophic obstructive cardiomyopathy (HOCM is cardiac hypertrophy of ventricular myocardium with left ventricular outflow tract obstruction. We report a pregnancy with HOCM after defibrillator implantation surgery. The patient was a 33-year-old nulligravida and was categorized as New York Heart Association class II. Her brain natriuretic peptide (BNP level was 724.6 pg/dL at preconception. She received careful pregnancy management. However, because frequent uterine contractions were observed at 25 weeks and 6 days of pregnancy, she was hospitalized, and magnesium sulfate was started as a tocolytic agent. At 27 weeks and 5 days of pregnancy, she had respiratory discomfort and orthopnea with a sudden decrease in peripheral oxygen saturation. Cardiac ultrasonography showed a worsened condition of HOCM and her BNP level was 1418.0 pg/mL. We performed an emergent cesarean section and she delivered a boy weighing 999 g. The Apgar score was 8 and 9 points at 1 and 5 minutes, respectively. The mother’s heart failure quickly improved after birth and she was discharged at 10 days postoperatively. Fluctuations in circulatory dynamics during pregnancy may sometimes exacerbate heart disease. Therefore, the risks should be fully explained and careful assessment of cardiac function should be performed during pregnancy in patients with severe HOCM.

  12. Mechanical dispersion and global longitudinal strain by speckle tracking echocardiography: Predictors of appropriate implantable cardioverter defibrillator therapy in hypertrophic cardiomyopathy.

    Science.gov (United States)

    Candan, Ozkan; Gecmen, Cetin; Bayam, Emrah; Guner, Ahmet; Celik, Mehmet; Doğan, Cem

    2017-06-01

    In this study, we investigated whether mechanical dispersion which reflects electrical abnormality and other echocardiographic and clinic parameters predict appropriate ICD shock in patients undergone ICD implantation for hypertrophic cardiomyopathy. Sixty-three patients who received ICD implantation for primary or secondary prevention were included in the study. Patients' clinical, electrocardiographic, 2D classic, and speckle tracking echocardiographic data were collected. Mechanical dispersion was defined as the standard deviation of time to peak negative strain in 18 left ventricular segments. Appropriate ICD therapy was defined as cardioversion or defibrillation due to ventricular tachycardia or fibrillation. Patients were divided into two groups as occurrence or the absence of appropriate ICD therapy. A total of 17 (26.9%) patients were observed to have an appropriate ICD therapy during follow-up periods. In patients who performed appropriate ICD therapy, a larger left atrial volume index, higher sudden cardiac death (SCD)-Risk Score, longer mechanical dispersion, and decreased global longitudinal peak strain (GLPS) were observed. In multivariate logistic regression analysis, including (GLPS, mechanical dispersion, LAVi, and SCD-Risk Score) was used to determine independent predictors of occurrence of appropriate ICD therapy during the follow-up. Mechanical dispersion, GLPS, and SCD-Risk Score were found to be independent predictors of occurrence of appropriate ICD therapy. Mechanical dispersion, GLPS, and SCD-Risk Score were found to be predictive for appropriate ICD therapy in patients receiving ICD implantation. Readily measurable mechanical dispersion and GLPS could be helpful to distinguish patients at high risk who could optimally benefit from ICD therapy. © 2017, Wiley Periodicals, Inc.

  13. Implantable defibrillator therapy: more than defibrillation...

    NARCIS (Netherlands)

    D.A.M.J. Theuns (Dominic)

    2005-01-01

    textabstractDuring the past 25 years, the implantable cardioverter-defibrillator (ICD) has evolved from the treatment of last resort to the gold standard for patients at high risk for life­threatening ventricular tachyarrhythmias. Patients at high risk include those who survived life-threatening

  14. Is metal artefact reduction mandatory in cardiac PET/CT imaging in the presence of pacemaker and implantable cardioverter defibrillator leads?

    Energy Technology Data Exchange (ETDEWEB)

    Ghafarian, Pardis [Shahid Beheshti University, Department of Radiation Medicine, Tehran (Iran, Islamic Republic of); Geneva University Hospital, Division of Nuclear Medicine, Geneva 4 (Switzerland); Tehran University of Medical Sciences, Research Center for Science and Technology in Medicine, Tehran (Iran, Islamic Republic of); Aghamiri, S.M.R. [Shahid Beheshti University, Department of Radiation Medicine, Tehran (Iran, Islamic Republic of); Ay, Mohammad R. [Tehran University of Medical Sciences, Research Center for Science and Technology in Medicine, Tehran (Iran, Islamic Republic of); Tehran University of Medical Sciences, Department of Medical Physics and Biomedical Engineering, Tehran (Iran, Islamic Republic of); Tehran University of Medical Sciences, Research Institute for Nuclear Medicine, Tehran (Iran, Islamic Republic of); Rahmim, Arman [Johns Hopkins University, Department of Radiology, Baltimore, MD (United States); Schindler, Thomas H. [Geneva University, Cardiovascular Center, Nuclear Cardiology, Geneva (Switzerland); Ratib, Osman [Geneva University Hospital, Division of Nuclear Medicine, Geneva 4 (Switzerland); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine, Geneva 4 (Switzerland); Geneva University, Geneva Neuroscience Center, Geneva (Switzerland)

    2011-02-15

    Cardiac PET/CT imaging is often performed in patients with pacemakers and implantable cardioverter defibrillator (ICD) leads. However, metallic implants usually produce artefacts on CT images which might propagate to CT-based attenuation-corrected (CTAC) PET images. The impact of metal artefact reduction (MAR) for CTAC of cardiac PET/CT images in the presence of pacemaker, ICD and ECG leads was investigated using both qualitative and quantitative analysis in phantom and clinical studies. The study included 14 patients with various leads undergoing perfusion and viability examinations using dedicated cardiac PET/CT protocols. The PET data were corrected for attenuation using both artefactual CT images and CT images corrected using the MAR algorithm. The severity and magnitude of metallic artefacts arising from these leads were assessed on both linear attenuation coefficient maps ({mu}-maps) and attenuation-corrected PET images. CT and PET emission data were obtained using an anthropomorphic thorax phantom and a dedicated heart phantom made in-house incorporating pacemaker and ICD leads attached at the right ventricle of the heart. Volume of interest-based analysis and regression plots were performed for regions related to the lead locations. Bull's eye view analysis was also performed on PET images corrected for attenuation with and without the MAR algorithm. In clinical studies, the visual assessment of PET images by experienced physicians and quantitative analysis did not reveal erroneous interpretation of the tracer distribution or significant differences when PET images were corrected for attenuation with and without MAR. In phantom studies, the mean differences between tracer uptake obtained without and with MAR were 10.16{+-}2.1% and 6.86{+-}2.1% in the segments of the heart in the vicinity of metallic ICD or pacemaker leads, and were 4.43{+-}0.5% and 2.98{+-}0.5% in segments far from the leads. Although the MAR algorithm was able to effectively improve

  15. Manual for the psychotherapeutic treatment of acute and post-traumatic stress disorders following multiple shocks from implantable cardioverter defibrillator (ICD).

    Science.gov (United States)

    Jordan, Jochen; Titscher, Georg; Peregrinova, Ludmila; Kirsch, Holger

    2013-01-01

    In view of the increasing number of implanted cardioverter defibrillators (ICD), the number of people suffering from so-called "multiple ICD shocks" is also increasing. The delivery of more than five shocks (appropriate or inappropriate) in 12 months or three or more shocks (so called multiple shocks) in a short time period (24 hours) leads to an increasing number of patients suffering from severe psychological distress (anxiety disorder, panic disorder, adjustment disorder, post-traumatic stress disorder). Untreated persons show chronic disease processes and a low rate of spontaneous remission and have an increased morbidity and mortality. Few papers have been published concerning the psychotherapeutic treatment for these patients. The aim of this study is to develop a psychotherapeutic treatment for patients with a post-traumatic stress disorder or adjustment disorder after multiple ICD shocks. Explorative feasibility study: Treatment of 22 patients as a natural design without randomisation and without control group. The period of recruitment was three years, from March 2007 to March 2010. The study consisted of two phases: in the first phase (pilot study) we tested different components and dosages of psychotherapeutic treatments. The final intervention programme is presented in this paper. In the second phase (follow-up study) we assessed the residual post-traumatic stress symptoms in these ICD patients. The time between treatment and follow-up measurement was 12 to 30 months. Thirty-one patients were assigned to the Department of Psychocardiology after multiple shocks. The sample consisted of 22 patients who had a post-traumatic stress disorder or an adjustment disorder and were willing and able to participate. They were invited for psychological treatment. 18 of them could be included into the follow-up study. After the clinical assessment at the beginning and at the end of the inpatient treatment a post-treatment assessment with questionnaires followed. In

  16. Implantable Cardioverter-Defibrillators in Patients With a Continuous-Flow Left Ventricular Assist Device: An Analysis of the INTERMACS Registry.

    Science.gov (United States)

    Clerkin, Kevin J; Topkara, Veli K; Demmer, Ryan T; Dizon, Jose M; Yuzefpolskaya, Melana; Fried, Justin A; Mai, Xingchen; Mancini, Donna M; Takeda, Koji; Takayama, Hiroo; Naka, Yoshifumi; Colombo, Paolo C; Garan, A Reshad

    2017-12-01

    This study sought to determine if the presence of implantable cardioverter-defibrillators (ICD) provided a mortality benefit during continuous-flow left ventricular assist device (LVAD) support. An ICD decreases mortality in selected patients with advanced heart failure and have been associated with reduced mortality in patients with pulsatile LVAD. However, it is unclear whether that benefit extends to patients with a contemporary continuous-flow LVAD. Propensity score matching was used to generate a cohort of patients with similar baseline characteristics. The primary outcome was freedom from death during LVAD support. Secondary endpoints included freedom from unexpected death, likelihood of transplantation and recovery, and adverse events. Among 16,384 eligible patients in the Interagency Registry for Mechanically Assisted Circulatory Support registry, 2,209 patients with an ICD and 2,209 patients without one had similar propensity scores and were included. The presence of an ICD was associated with an increased mortality risk (hazard ratio: 1.20; 95% confidence interval [CI]: 1.04 to 1.39; p = 0.013) and an increased risk of unexpected death during device support (HR: 1.33; 95% CI: 1.03 to 1.71; p = 0.03). Patients with an ICD were more likely to undergo transplantation (HR: 1.16; 95% CI: 0.99 to 1.35; p = 0.06) and less likely to have LVAD explant for recovery (HR: 0.53, 95% CI: 0.29 to 0.98; p = 0.04). Patients with an ICD had a higher rate of treated ventricular arrhythmias (rate ratio: 1.27; 95% CI: 1.10 to 1.48; p = 0.001) and rehospitalization (rate ratio: 1.08; 95% CI: 1.04 to 1.12; p < 0.0001), but rates of hemorrhagic stroke were similar (rate ratio: 1.01; 95% CI: 0.81 to 1.26; p = 0.98). Among patients with a continuous flow LVAD, the presence of an ICD was not associated with reduced mortality. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  17. [The pacemaker and implantable cardioverter-defibrillator registry of the Italian Association Arrhythmology Cardiac Pacing and cardiac pacing - annual report 2013].

    Science.gov (United States)

    Proclemer, Alessandro; Zecchin, Massimo; D'Onofrio, Antonio; Botto, Giovanni Luca; Rebellato, Luca; Ghidina, Marco; Bianco, Giulia; Bernardelli, Emanuela; Pucher, Elsa; Gregori, Dario

    2014-11-01

    The pacemaker (PM) and implantable cardioverter-defibrillator (ICD) Registry of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) monitors the main epidemiological data in real-world practice. The survey for the 2013 activity collects information about demographics, clinical characteristics, main indications for PM/ICD therapy and device types from the Italian collaborating centers. The Registry collects prospectively national PM and ICD implantation activity on the basis of European cards. PM Registry: data about 25 419 PM implantations were collected (19 134 first implant and 6285 replacements). The number of collaborating centers was 275. Median age of treated patients was 80 years (74 quartile I; 86 quartile III). ECG indications included atrioventricular conduction disorders in 43.6% of first PM implants, sick sinus syndrome in 24.7%, atrial fibrillation plus bradycardia in 12.9%, other in 18.8%. Among atrioventricular conduction defects, third-degree atrioventricular block was the most common type (23.2% of first implants). Use of single-chamber PMs was reported in 27.2% of first implants, of dual-chamber PMs in 62.6%, of PMs with cardiac resynchronization therapy (CRT) in 1.8%, and of single lead atrial-synchronized ventricular stimulation (VDD/R PMs) in 8.4%. ICD Registry: data about 16 519 ICD implantations were collected (11 474 first implants and 5045 replacements). The number of collaborating centers was 430. Median age of treated patients was 71 years (63 quartile I; 77 quartile III). Primary prevention indication was reported in 76% of first implants, secondary prevention in 24.0% (cardiac arrest in 7.8%). A single-chamber ICD was used in 27.2% of first implants, dual-chamber in 35.9% and biventricular in 36.8%. The PM and ICD Registry appears fundamental for monitoring PM and ICD utilization on a large national scale with rigorous examination of demographics and clinical indications. The PM Registry showed stable electrocardiographic

  18. Sex and Race/Ethnicity Differences in Implantable Cardioverter-Defibrillator Counseling and Use Among Patients Hospitalized With Heart Failure: Findings from the Get With The Guidelines-Heart Failure Program.

    Science.gov (United States)

    Hess, Paul L; Hernandez, Adrian F; Bhatt, Deepak L; Hellkamp, Anne S; Yancy, Clyde W; Schwamm, Lee H; Peterson, Eric D; Schulte, Phillip J; Fonarow, Gregg C; Al-Khatib, Sana M

    2016-08-16

    Previous studies have found that women and black patients eligible for a primary prevention implantable cardioverter-defibrillator (ICD) are less likely than men or white patients to receive one. We performed an observational analysis of the Get With The Guidelines-Heart Failure Program from January 1, 2011, to March 21, 2014. Patients admitted with heart failure and an ejection fraction ≤35% without an ICD were included. Rates of ICD counseling among eligible patients and ICD receipt among counseled patients were examined by sex and race/ethnicity. Among 21 059 patients from 236 sites, 4755 (22.6%) received predischarge ICD counseling. Women were counseled less frequently than men (19.3% versus 24.6%, Prace/ethnic group 14.4% versus white 24.3%, Pdifferences by race and ethnicity persisted. © 2016 American Heart Association, Inc.

  19. Development and evaluation of the EOL-ICDQ as a measure of experiences, attitudes and knowledge in end-of-life in patients living with an implantable cardioverter defibrillator.

    Science.gov (United States)

    Thylén, Ingela; Wenemark, Marika; Fluur, Christina; Strömberg, Anna; Bolse, Kärstin; Årestedt, Kristofer

    2014-04-01

    Due to extended indications and resynchronization therapy, many implantable cardioverter defibrillator (ICD) recipients will experience progressive co-morbid conditions and will be more likely to die of causes other than cardiac death. It is therefore important to elucidate the ICD patients' preferences when nearing end-of-life. Instead of avoiding the subject of end-of-life, a validated questionnaire may be helpful to explore patients' experiences and attitudes about end-of-life concerns and to assess knowledge of the function of the ICD in end-of-life. Validated instruments assessing patients' perspective concerning end-of-life issues are scarce. The purpose of this study was to develop and evaluate respondent satisfaction and measurement properties of the 'Experiences, Attitudes and Knowledge of End-of-Life Issues in Implantable Cardioverter Defibrillator Patients' Questionnaire' (EOL-ICDQ). The instrument was tested for validity, respondent satisfaction, and for homogeneity and stability in the Swedish language. An English version of the EOL-ICDQ was validated, but has not yet been pilot tested. The final instrument contained three domains, which were clustered into 39 items measuring: experiences (10 items), attitudes (18 items), and knowledge (11 items) of end-of-life concerns in ICD patients. In addition, the questionnaire also contained items on socio-demographic background (six items) and ICD-specific background (eight items). The validity and reliability properties were considered sufficient. The EOL-ICDQ has the potential to be used in clinical practice and future research. Further studies are needed using this instrument in an Anglo-Saxon context with a sample of English-speaking ICD recipients.

  20. Clinical safety of an MRI conditional implantable cardioverter defibrillator system: A prospective Monocenter ICD-Magnetic resonance Imaging feasibility study (MIMI).

    Science.gov (United States)

    Kypta, Alexander; Blessberger, Hermann; Hoenig, Simon; Saleh, Karim; Lambert, Thomas; Kammler, Juergen; Fellner, Franz; Lichtenauer, Michael; Steinwender, Clemens

    2016-03-01

    The aim of this study was to evaluate the safety and efficacy of the Lumax 740(®) Implantable Cardioverter Defibrillator (ICD) system in patients undergoing a defined 1.5 Tesla (T) MRI. Between November 2013 and April 2014, eighteen patients (age range, 41-78 years; mean age, 64 years) implanted with a Lumax 740(®) ICD system for at least 6 weeks before an MRI were enrolled into this single-center feasibility study. The local ethics committee approved the study before patients gave written informed consent. Patients underwent defined MRI 1.5T of the brain and lower lumbar spine with three safety follow-up evaluations obtained during the 3-month study period. Data were analyzed descriptively. Study endpoints were the absence of either MRI and pacing system related serious adverse device effects (SADE), or of a ventricular pacing threshold increase >0.5V, or of an R-wave amplitude attenuation battery status. Sixteen patients completed the MRI and the follow-up period. As no SADE occurred, the SADE free rate was 100%. Freedom from ventricular pacing threshold increase was 100% (16/16; 95%CI: 82.9%; 100.0%). There were no significant differences between baseline and follow-up measurements of sensing amplitudes (-0.58 ± 2.07 mV, P = 0.239, -0.41 ± 1.04 mV, P = 0.133, and -0.25 ± 1.36 mV, P = 0.724, for immediately after, 1 month and 3 months after MRI scan, respectively) and pacing thresholds (-0.047 ± 0.18 V, P = 0.317, -0.019 ± 0.11 V, P = 0.490, and 0.075 ± 0.19 V, P = 0.070, for immediately after, 1 month and 3 months after MRI scan, respectively). Lead impedances after the MRI scan were significantly lower as compared with baseline values (-22.8 ± 21.69 Ω, P = 0.001, -21.62 ± 39.71 Ω, P = 0.040, and -33.68 ± 57.73 Ω, P = 0.018, for immediately after, 1 month and 3 months after MRI scan, respectively). MRI scans in patients with MRI conditional ICD system (Lumax 740(

  1. Subcutaneous Implantable Cardioverter-Defibrillator

    Science.gov (United States)

    ... discriminator functions and lacks antitachycardia pacing. Expanded Programmability Programming that allows lower shock energies and the ability ... 2014 American Heart Association, Inc. References 1. ↵ Weiss R , Knight BP , Gold MR , Leon AR , Herre JM , ...

  2. Diagnostic Value of MRI in Patients With Implanted Pacemakers and Implantable Cardioverter-Defibrillators Across a Cross Population: Does the Benefit Justify the Risk? A Proof of Concept Study.

    Science.gov (United States)

    Samar, Huma; Yamrozik, June A; Williams, Ronald B; Doyle, Mark; Shah, Moneal; Bonnet, Christopher A; Biederman, Robert W W

    2017-09-01

    The objective of this study was to assess the diagnostic usefulness of thoracic and nonthoracic magnetic resonance imaging (MRI) imaging in patients with implantable cardiac devices (permanent pacemaker or implantable cardioverter-defibrillators [ICDs]) to determine if there was a substantial benefit to patients with regard to diagnosis and/or management. MRI is infrequently performed on patients with conventional pacemakers or ICDs. Multiple studies have documented the safety of MRI scans in patients with implanted devices, yet the diagnostic value of this approach has not been established. Evaluation data were acquired in 136 patients with implanted cardiac devices who underwent MRIs during a 10-year period at a single institution. Specific criteria were followed for all patients to objectively define if the diagnosis by MRI enhanced patient care; 4 questions were answered after scan interpretation by both MRI technologists and MRI physicians who performed the scan. 1) Did the primary diagnosis change? 2) Did the MRI provide additional information to the existing diagnosis? 3) Was the pre-MRI (tentative) diagnosis confirmed? 4) Did patient management change? If "Yes" was answered to any of the preceding questions, the MRI scan was considered to be of value to patient diagnosis and/or therapy. In 97% (n = 132) of patients, MR added value to patient diagnosis and management. In 49% (n = 67) of patients, MRI added additional valuable information to the primary diagnosis, and in 30% (n = 41) of patients, MRI changed the principle diagnosis and subsequent management of the patient. No safety issues were encountered, and no adverse effects of undergoing the MRI scan were noted in any patient. MRI in patients with implanted pacemakers and defibrillators added value to patient diagnosis and management, which justified the risk of the procedure. Published by Elsevier Inc.

  3. Cross validation in LULOO

    DEFF Research Database (Denmark)

    Sørensen, Paul Haase; Nørgård, Peter Magnus; Hansen, Lars Kai

    1996-01-01

    The leave-one-out cross-validation scheme for generalization assessment of neural network models is computationally expensive due to replicated training sessions. Linear unlearning of examples has recently been suggested as an approach to approximative cross-validation. Here we briefly review...... the linear unlearning scheme, dubbed LULOO, and we illustrate it on a systemidentification example. Further, we address the possibility of extracting confidence information (error bars) from the LULOO ensemble....

  4. Psychological intervention following implantation of an implantable defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; van den Broek, Krista C; Sears, Samuel F

    2007-01-01

    The medical benefits of the implantable cardioverter defibrillator (ICD) are unequivocal, but a subgroup of patients experiences emotional difficulties following implantation. For this subgroup, some form of psychological intervention may be warranted. This review provides an overview of current ...

  5. MR Imaging in patients with cardiac pacemakers and implantable cardioverter defibrillators. Consensus paper of the German Cardiac Society and the German Roentgen Society; MR-Untersuchungen bei Patienten mit Herzschrittmachern und implantierbaren Kardioverter-Defibrillatoren. Konsensuspapier der Deutschen Gesellschaft fuer Kardiologie (DGK) und der Deutschen Roentgengesellschaft (DRG)

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, Torsten [DRK Krankenhaus, Neuwied (Germany). Klinik fuer Diagnostische und Interventionelle Radiologie; Bauer, Wolfgang [Deutsches Zentrum fuer Herzinsuffizienz Univ. Wuerzburg (Germany). Med. Klinik und Poliklinik I Univ. Klinikum Wuerzburg; Fischbach, Katharina [Universitaetsklinikum Magdeburg (Germany). Klinik fuer Radiologie und Nuklearmedizin; and others

    2017-03-15

    This joint consensus paper of the German Roentgen Society and the German Cardiac Society provides physical and electrophysiological background information and specific recommendations for the procedural management of patients with cardiac pacemakers (PM) and implantable cardioverter defibrillators (ICD) undergoing magnetic resonance (MR) imaging. The paper outlines the responsibilities of radiologists and cardiologists regarding patient education, indications, and monitoring with modification of MR sequences and PM/ICD reprogramming strategies being discussed in particular. The aim is to optimize patient safety and to improve legal clarity in order to facilitate the access of SM/ICD patients to MR imaging.

  6. Elektrokirurgi hos patienter med pacemaker og implanterbar kardioverter-defibrillator

    DEFF Research Database (Denmark)

    Lønnberg, Ann Sophie Claire; Philberts, Berit Thornvig; Bonde, Christian

    2017-01-01

    Electrosurgery is a very useful tool and one of the most commonly used techniques. However, the technique can interfere with pacemakers and implantable cardioverter defibrillators. This article provides practical recommendations for the use of electrosurgery in these patients.......Electrosurgery is a very useful tool and one of the most commonly used techniques. However, the technique can interfere with pacemakers and implantable cardioverter defibrillators. This article provides practical recommendations for the use of electrosurgery in these patients....

  7. Rapid-rate nonsustained ventricular tachycardia found on implantable cardioverter-defibrillator interrogation: relationship to outcomes in the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial).

    Science.gov (United States)

    Chen, Jay; Johnson, George; Hellkamp, Anne S; Anderson, Jill; Mark, Daniel B; Lee, Kerry L; Bardy, Gust H; Poole, Jeanne E

    2013-05-28

    The aim of this study was to examine rapid-rate nonsustained ventricular tachycardia (RR-NSVT) during routine implantable cardioverter-defibrillator (ICD) evaluation in patients with heart failure and its relationship to outcomes. The clinical implications of RR-NSVT identified during routine ICD interrogation are unclear. In this study, the occurrence of RR-NSVT and its association with ICD shocks and mortality in SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial) were examined. The 811 patients who received ICDs in SCD-HeFT constituted the study population. The occurrence of RR-NSVT and its association with ICD shocks and mortality in SCD-HeFT were examined. RR-NSVT was documented on ICD interrogation in 186 of 811 patients (22.9%). The mean duration of RR-NSVT was 26.4 ± 9.1 beats (7.5 ± 2.6 s), with a mean cycle length of 259 ± 32 ms. Polymorphic RR-NSVT accounted for 56% of episodes. Compared with patients without RR-NSVT, those with RR-NSVT were less likely to be taking beta-blockers, statins, or aspirin at enrollment. After adjusting for other known predictors of mortality in SCD-HeFT, RR-NSVT was independently associated with appropriate ICD shocks (hazard ratio: 4.25; 95% confidence interval: 2.94 to 6.14; p interrogation should be considered an important clinical event. RR-NSVT during ICD interrogation is associated with appropriate ICD shocks and all-cause mortality. The clinical evaluation of patients with RR-NSVT should include intensification of medical therapy, particularly beta-blockers, or other appropriate clinical interventions. (Sudden Cardiac Death in Heart Failure Trial [SCD-HeFT]; NCT00000609). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  8. The natural history of new-onset heart failure with a severely depressed left ventricular ejection fraction: implications for timing of implantable cardioverter-defibrillator implantation.

    Science.gov (United States)

    Teeter, William A; Thibodeau, Jennifer T; Rao, Krishnasree; Brickner, M Elizabeth; Toto, Kathleen H; Nelson, Lauren L; Mishkin, Joseph D; Ayers, Colby R; Miller, Justin G; Mammen, Pradeep P A; Patel, Parag C; Markham, David W; Drazner, Mark H

    2012-09-01

    Guidelines recommend that patients with new-onset systolic heart failure (HF) receive a trial of medical therapy before an implantable cardiac defibrillator (ICD). This strategy allows for improvement of left ventricular ejection fraction (LVEF), thereby avoiding an ICD, but exposes patients to risk of potentially preventable sudden cardiac death during the trial of medical therapy. We reviewed a consecutive series of patients with HF of <6 months duration with a severely depressed LVEF (<30%) evaluated in a HF clinic (N = 224). The ICD implantation was delayed with plans to reassess LVEF approximately 6 months after optimization of β-blockers. Mortality was ascertained by the National Death Index. Follow-up echocardiograms were performed in 115 of the 224 subjects. Of these, 50 (43%) had mildly depressed or normal LVEF at follow-up ("LVEF recovery") such that an ICD was no longer indicated. In a conservative sensitivity analysis (using the entire study cohort, whether or not a follow-up echocardiogram was obtained, as the denominator), 22% of subjects had LVEF recovery. Mortality at 6, 12, and 18 months in the entire cohort was 2.3%, 4.5%, and 6.8%, respectively. Of 87 patients who tolerated target doses of β-blockers, only 1 (1.1%) died during the first 18 months. Patients with new-onset systolic HF have both a good chance of LVEF recovery and low 6-month mortality. Achievement of target β-blocker dose identifies a very low-risk population. These data support delaying ICD implantation for a trial of medical therapy. Copyright © 2012 Mosby, Inc. All rights reserved.

  9. Antibacterial Envelope Is Associated With Low Infection Rates After Implantable Cardioverter-Defibrillator and Cardiac Resynchronization Therapy Device Replacement: Results of the Citadel and Centurion Studies.

    Science.gov (United States)

    Henrikson, Charles A; Sohail, M Rizwan; Acosta, Helbert; Johnson, Eric E; Rosenthal, Lawrence; Pachulski, Roman; Dan, Dan; Paladino, Walter; Khairallah, Farhat S; Gleed, Kent; Hanna, Ibrahim; Cheng, Alan; Lexcen, Daniel R; Simons, Grant R

    2017-10-01

    This study sought to determine whether the nonabsorbable TYRX Antibacterial Envelope (TYRX) reduces major cardiovascular implantable electronic device (CIED) infections 12 months after implant. TYRX is a monofilament polypropylene mesh impregnated with minocycline and rifampin specifically designed to hold a CIED in place and elute antimicrobials over time. There are limited data on its ability to reduce CIED infections. We prospectively enrolled patients who underwent generator replacement with an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy device (CRT), treated with TYRX. The primary endpoints were major CIED infection and CIED mechanical complications. Given the differences in infection rates among ICD and CRT patients, 3 different control populations were used: a published benchmark rate for ICD patients, and both site-matched and comorbidity-matched controls groups for CRT patients. Overall, a major CIED infection occurred in 5 of 1,129 patients treated with TYRX (0.4%; 95% confidence interval: 0.0% to 0.9%), significantly lower than the 12-month benchmark rate of 2.2% (p = 0.0023). Among the TYRX-treated CRT cohort, the major CIED infection rate was 0.7% compared with an infection rate of 1.0% and 1.3% (p = 0.38 and p = 0.02) in site-matched and comorbidity-matched control groups, respectively. Among the ICD group, the 12-month infection rate was 0.2% compared with the published benchmark of 2.2% (p = 0.0052). The most common CIED mechanical complication in study patients was pocket hematoma, which occurred in 18 of the 1,129 patients (1.6%; 95% confidence interval: 0.8 to 2.5), which is comparable with a published rate of 1.6%. Use of TYRX was associated with a lower major CIED infection rate. (TYRX™ Envelope for Prevention of Infection Following Replacement With a CRT or ICD; [Centurion]; NCT01043861/NCT01043705). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights

  10. Living with Your Implantable Cardioverter Defibrillator (ICD)

    Science.gov (United States)

    ... and Live Our Interactive Cardiovascular Library has detailed animations and illustrations to help you learn about conditions, treatments and procedures related to heart disease and stroke. Popular Articles 1 Understanding Blood Pressure Readings 2 Sodium and Salt 3 Heart Attack Symptoms ...

  11. Cardioverter-Defibrillator: A Treatment for Arrhythmia

    Science.gov (United States)

    ... abdomen (stomach area). It can go in a “pocket” under your skin or in a muscle. The ... counter Products Procedures & Devices Prescription Medicines Health Tools Dictionary Symptom Checker BMI Calculator myhealthfinder Immunization Schedules Nutrient ...

  12. Risk of chronic anxiety in implantable defibrillator patients

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; den Broek, Krista C van; Theuns, Dominic A M J

    2011-01-01

    Little is known about the prevalence of chronic anxiety in patients with an implantable cardioverter defibrillator (ICD). In a multi-center, prospective study, we examined 1) the prevalence of chronic anxiety (i.e., patients anxious at implantation and 12 months), and 2) predictors of chronic...... anxiety....

  13. Shock whilst gardening--implantable defibrillators & lawn mowers.

    Science.gov (United States)

    Von Olshausen, G; Lennerz, C; Grebmer, C; Pavaci, H; Kolb, C

    2014-02-01

    Electromagnetic interference with implantable cardioverter defibrillators (ICDs) can cause inappropriate shock delivery or temporary inhibition of ICD functions. We present a case of electromagnetic interference between a lawn mower and an ICD resulting in an inappropriate discharge of the device due to erroneous detection of ventricular fibrillation.

  14. Prophylactic implantable defibrillator in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior ventricular fibrillation or sustained ventricular tachycardia.

    LENUS (Irish Health Repository)

    Corrado, Domenico

    2010-09-21

    The role of implantable cardioverter-defibrillator (ICD) in patients with arrhythmogenic right ventricular cardiomyopathy\\/dysplasia and no prior ventricular fibrillation (VF) or sustained ventricular tachycardia is an unsolved issue.

  15. An unusual etiological agent of implantable cardioverter device endocarditis: Corynebacterium mucifaciens

    Directory of Open Access Journals (Sweden)

    Adnan Kaya

    2016-03-01

    Full Text Available Cardiac pacing devices and implantable cardioverter defibrillator (ICD are becoming the mainstay of therapy in cardiology and infective endocarditis (IE and pocket infection; however, these devices require careful monitoring. Here, we describe a case of a 68-year-old female with an ICD presenting with a previously unknown etiological agent of IE, Corynebacterium mucifaciens.

  16. A patch in the pectoral position lowers defibrillation threshold.

    Science.gov (United States)

    Karasik, P; Solomon, A; Verdino, R; Moore, H; Rodak, D; Hannan, R; Fletcher, R

    1997-06-01

    Implantable pacemaker cardioverter defibrillators are now available with biphasic waveforms, which have been shown to markedly improve defibrillation thresholds (DFTs). However, in a number of patients the DFT remains high. Also, DFT may increase after implantation, especially if antiarrhythmic drugs are added. We report on the use of a subcutaneous patch in the pectoral position in 15 patients receiving a transvenous defibrillator as a method of easily reducing the DFT. A 660-mm2 patch electrode was placed beneath the generator in a pocket created on the pectoral fascia. The energy required for defibrillation was lowered by 56% on average, and the system impedance was lowered by a mean of 25%. This maneuver allowed all patients to undergo a successful implant with adequate safety margin.

  17. Short- and long-term performance of a tripolar down-sized single lead for implantable cardioverter defibrillator treatment: a randomized prospective European multicenter study. European Endotak DSP Investigator Group.

    Science.gov (United States)

    Sandstedt, B; Kennergren, C; Schaumann, A; Herse, B; Neuzner, J

    1998-11-01

    A new, thinner (10 Fr) and more flexible, single-pass transvenous endocardial ICD lead, Endotak DSP, was compared with a conventional lead, Endotak C, as a control in a prospective randomized multicenter study in combination with a nonactive can ICD. A total of 123 patients were enrolled, 55 of whom received a down-sized DSP lead. Lead-alone configuration was successfully implanted in 95% of the DSP patients vs 88% in the control group. The mean defibrillation threshold (DFT) was determined by means of a step-down protocol, and was identical in the two groups, 10.5 +/- 4.8 J in the DSP group versus 10.5 +/- 4.8 J in the control group. At implantation, the DSP mean pacing threshold was lower, 0.51 +/- 0.18 V versus 0.62 +/- 0.35 V (p < 0.05) in the control group, and the mean pacing impedance higher, 594 +/- 110 omega vs 523 +/- 135 omega (p < 0.05). During the follow-up period, the statistically significant difference in thresholds disappeared, while the difference in impedance remained. Tachyarrhythmia treatment by shock or antitachycardia pacing (ATP) was delivered in 53% and 41%, respectively, of the patients with a 100% success rate. In the DSP group, all 28 episodes of polymorphic ventricular tachycardia or ventricular fibrillation were converted by the first shock as compared to 57 of 69 episodes (83%) in the control group (p < 0.05). Monomorphic ventricular tachycardias were terminated by ATP alone in 96% versus 94%. Lead related problems were minor and observed in 5% and 7%, respectively. In summary, both leads were safe and efficacious in the detection and treatment of ventricular tachyarrhythmias. There were no differences between the DSP and control groups regarding short- or long-term lead related complications.

  18. Linear Unlearning for Cross-Validation

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Larsen, Jan

    1996-01-01

    The leave-one-out cross-validation scheme for generalization assessment of neural network models is computationally expensive due to replicated training sessions. In this paper we suggest linear unlearning of examples as an approach to approximative cross-validation. Further, we discuss...... time series prediction benchmark demonstrate the potential of the linear unlearning technique...

  19. An eight-year prospective controlled study about the safety and diagnostic value of cardiac and non-cardiac 1.5-T MRI in patients with a conventional pacemaker or a conventional implantable cardioverter defibrillator.

    Science.gov (United States)

    Lupo, Pierpaolo; Cappato, Riccardo; Di Leo, Giovanni; Secchi, Francesco; Papini, Giacomo D E; Foresti, Sara; Ali, Hussam; De Ambroggi, Guido M G; Sorgente, Antonio; Epicoco, Gianluca; Cannaò, Paola M; Sardanelli, Francesco

    2018-06-01

    To investigate safety and diagnostic value of 1.5-T MRI in carriers of conventional pacemaker (cPM) or conventional implantable defibrillator (cICD). We prospectively compared cPM/cICD-carriers undergoing MRI (study group, SG), excluding those device-dependent or implanted cPM/cICD-carriers undergoing chest x-ray, CT or follow-up (reference group, RG). 142 MRI (55 cardiac) were performed in 120 patients with cPM (n=71) or cICD (n=71). In the RG 98 measurements were performed in 95 patients with cPM (n=40) or cICD (n=58). No adverse events were observed. No MRI prolonged/interrupted. All cPM/cICD were correctly reprogrammed after MRI without malfunctions. One temporary communication failure was observed in one cPM-carrier. Immediately after MRI, 12/14 device interrogation parameters did not change significantly (clinically negligible changes of battery voltage and cICD charging time), without significant variations for SG versus RG. Three-12 months after MRI, 9/11 device interrogation parameters did not change significantly (clinically negligible changes of battery impedance/voltage). Non-significant changes of three markers of myocardial necrosis. Non-cardiac MRI: 82/87 diagnostic without artefacts; 4/87 diagnostic with artefacts; 1/87 partially diagnostic. Cardiac MRI: in cPM-carriers, 14/15 diagnostic with artefacts, 1/15 partially diagnostic; in cICD-carriers, 9/40 diagnostic with artefacts, 22 partially diagnostic, nine non-diagnostic. A favourable risk-benefit ratio of 1.5-T MRI in cPM/cICD carriers was reported. • Cooperation between radiologists and cardiac electrophysiologists allowed safe 1.5-T MRI in cPM/cICD-carriers. • No adverse events for 142 MRI in 71 cPM-carriers and 71 cICD-carriers. • Ninety-nine per cent (86/87) of non-cardiac MRI in cPM/cICD-carriers were diagnostic. • All cPM-carrier cardiac MRIs had artefacts, 14 examinations diagnostic, 1 partially diagnostic. • Twenty-three per cent (9/40) of cardiac MRI in cICD-carriers were non-diagnostic.

  20. The learning curve associated with the introduction of the subcutaneous implantable defibrillator

    NARCIS (Netherlands)

    Knops, Reinoud E.; Brouwer, Tom F.; Barr, Craig S.; Theuns, Dominic A.; Boersma, Lucas; Weiss, Raul; Neuzil, Petr; Scholten, Marcoen; Lambiase, Pier D.; Leon, Angel R.; Hood, Margaret; Jones, Paul W.; Wold, Nicholas; Grace, Andrew A.; Olde Nordkamp, Louise R. A.; Burke, Martin C.

    2016-01-01

    Aims The subcutaneous implantable cardioverter defibrillator (S-ICD) was introduced to overcome complications related to transvenous leads. Adoption of the S-ICD requires implanters to learn a new implantation technique. The aim of this study was to assess the learning curve for S-ICD implanters

  1. The learning curve associated with the introduction of the subcutaneous implantable defibrillator

    NARCIS (Netherlands)

    R.E. Knops (Reinoud); T.F. Brouwer (Tom F.); C.S. Barr (Craig); D.A.M.J. Theuns (Dominic); L. Boersma (Lucas); R. Weiss (Ram); P. Neuzil (Petr); M.F. Scholten (Marcoen); P.D. Lambiase (Pier); A. Leon (Angel); A.M. Hood (Margaret); P. Jones; Wold, N. (Nicholas); Grace, A.A. (Andrew A.); L.R.A. Olde Nordkamp (Louise R.A.); M.C. Burke (Martin)

    2016-01-01

    textabstractAims: The subcutaneous implantable cardioverter defibrillator (S-ICD) was introduced to overcome complications related to transvenous leads. Adoption of the S-ICD requires implanters to learn a new implantation technique. The aim of this study was to assess the learning curve for S-ICD

  2. Long-Term Clinical Outcomes of Subcutaneous Versus Transvenous Implantable Defibrillator Therapy

    NARCIS (Netherlands)

    Brouwer, Tom F.; Yilmaz, Dilek; Lindeboom, Robert; Buiten, Maurits S.; Olde Nordkamp, Louise R. A.; Schalij, Martin J.; Wilde, Arthur A.; van Erven, Lieselot; Knops, Reinoud E.

    2016-01-01

    Transvenous implantable cardioverter-defibrillators (TV-ICDs) improve survival in patients at risk for sudden cardiac death, but complications remain an important drawback. The subcutaneous ICD (S-ICD) was developed to overcome lead-related complications. Comparison of clinical outcomes of both

  3. Combined leadless pacemaker and subcutaneous implantable defibrillator therapy: feasibility, safety, and performance

    NARCIS (Netherlands)

    Tjong, F. V. Y.; Brouwer, T. F.; Smeding, L.; Kooiman, K. M.; de Groot, J. R.; Ligon, D.; Sanghera, R.; Schalij, M. J.; Wilde, A. A. M.; Knops, R. E.

    2016-01-01

    The subcutaneous implantable cardioverter-defibrillator (S-ICD) and leadless pacemaker (LP) are evolving technologies that do not require intracardiac leads. However, interactions between these two devices are unexplored. We investigated the feasibility, safety, and performance of combined LP and

  4. Towards Low Energy Atrial Defibrillation

    Directory of Open Access Journals (Sweden)

    Philip Walsh

    2015-09-01

    Full Text Available A wireless powered implantable atrial defibrillator consisting of a battery driven hand-held radio frequency (RF power transmitter (ex vivo and a passive (battery free implantable power receiver (in vivo that enables measurement of the intracardiac impedance (ICI during internal atrial defibrillation is reported. The architecture is designed to operate in two modes: Cardiac sense mode (power-up, measure the impedance of the cardiac substrate and communicate data to the ex vivo power transmitter and cardiac shock mode (delivery of a synchronised very low tilt rectilinear electrical shock waveform. An initial prototype was implemented and tested. In low-power (sense mode, >5 W was delivered across a 2.5 cm air-skin gap to facilitate measurement of the impedance of the cardiac substrate. In high-power (shock mode, >180 W (delivered as a 12 ms monophasic very-low-tilt-rectilinear (M-VLTR or as a 12 ms biphasic very-low-tilt-rectilinear (B-VLTR chronosymmetric (6ms/6ms amplitude asymmetric (negative phase at 50% magnitude shock was reliably and repeatedly delivered across the same interface; with >47% DC-to-DC (direct current to direct current power transfer efficiency at a switching frequency of 185 kHz achieved. In an initial trial of the RF architecture developed, 30 patients with AF were randomised to therapy with an RF generated M-VLTR or B-VLTR shock using a step-up voltage protocol (50–300 V. Mean energy for successful cardioversion was 8.51 J ± 3.16 J. Subsequent analysis revealed that all patients who cardioverted exhibited a significant decrease in ICI between the first and third shocks (5.00 Ω (SD(σ = 1.62 Ω, p < 0.01 while spectral analysis across frequency also revealed a significant variation in the impedance-amplitude-spectrum-area (IAMSA within the same patient group (|∆(IAMSAS1-IAMSAS3[1 Hz − 20 kHz] = 20.82 Ω-Hz (SD(σ = 10.77 Ω-Hz, p < 0.01; both trends being absent in all patients that failed to cardiovert

  5. A theory of cross-validation error

    OpenAIRE

    Turney, Peter D.

    1994-01-01

    This paper presents a theory of error in cross-validation testing of algorithms for predicting real-valued attributes. The theory justifies the claim that predicting real-valued attributes requires balancing the conflicting demands of simplicity and accuracy. Furthermore, the theory indicates precisely how these conflicting demands must be balanced, in order to minimize cross-validation error. A general theory is presented, then it is developed in detail for linear regression and instance-bas...

  6. Single-Coil Defibrillator Leads Yield Satisfactory Defibrillation Safety Margin in Hypertrophic Cardiomyopathy.

    Science.gov (United States)

    Okamura, Hideo; Friedman, Paul A; Inoue, Yuko; Noda, Takashi; Aiba, Takeshi; Yasuda, Satoshi; Ogawa, Hisao; Kamakura, Shiro; Kusano, Kengo; Espinosa, Raul E

    2016-09-23

    Single-coil defibrillator leads have gained favor because of their potential ease of extraction. However, a high defibrillation threshold remains a concern in patients with hypertrophic cardiomyopathy (HCM), and in many cases, dual-coil leads have been used for this patient group. There is little data on using single-coil leads for HCM patients. We evaluated 20 patients with HCM who received an implantable cardioverter-defibrillator (ICD) on the left side in combination with a dual-coil lead. Two sets of defibrillation tests were performed in each patient, one with the superior vena cava (SVC) coil "on" and one with the SVC coil "off". ICDs were programmed to deliver 25 joules (J) for the first attempt followed by maximum energy (35 J or 40 J). Shock impedance and shock pulse width at 25 J in each setting as well as the results of the shock were analyzed. All 25-J shocks in both settings successfully terminated ventricular fibrillation. However, shock impedance and pulse width increased substantially with the SVC coil programmed "off" compared with "on" (66.4±6.1 ohm and 14.0±1.3 ms "off" vs. 41.9±5.0 ohm and 9.3±0.8 ms "on", Psatisfactory safety margin for 35-J devices. Single-coil leads appear appropriate for left-sided implantation in this patient group. (Circ J 2016; 80: 2199-2203).

  7. Web-Based Distress Management for Implantable Cardioverter Defibrillator Patients

    DEFF Research Database (Denmark)

    Habibović, Mirela; Denollet, Johan; Cuijpers, Pim

    2017-01-01

    distress post-ICD implantation. The WEB-based distress management program for ICD patients (WEBCARE) was developed to mitigate anxiety and depression and enhance health-related quality of life in ICD patients. This study investigates the 6- and 12-months outcomes. METHOD: A total of 289 consecutive ICD...... care as usual. RESULTS: Current findings show no significant difference on anxiety, depression or quality of life between the WEBCARE and Usual Care group at 6- and 12-months postimplantation. CONCLUSIONS: In this clinical trial of a Web-based behavioral intervention for ICD patients, the Web...

  8. Sexual Health for Patients with an Implantable Cardioverter Defibrillator

    Science.gov (United States)

    ... sex for most patients represents only a moderate stress on the heart. Proposed Strategy Sex is a common concern, but most sexual activity ... all of your efforts, there are times when stress like this cannot be handled by ... patients should not engage in sex. Even if you feel you are not physically ...

  9. Questions to Ask Your Doctor--Implantable Cardioverter Defibrillator (ICD)

    Science.gov (United States)

    ... family member or I still drive, travel, have sex, work out or continue other activities we enjoy? How ... in Children • Arrhythmia Tools & Resources Answers by Heart Fact Sheets Learn and live with our downloadable patient ...

  10. How to Respond to an Implantable Cardioverter-Defibrillator Recall

    Science.gov (United States)

    ... managing your emotions appropriately and being proactive. Behavioral Management Plan Your best plan of action is to ... recall for all patients. The recall of 1 brand of ICD does not mean that there is ...

  11. [Full dental rehabilitation of a patient with implantable cardioverter defibrillator].

    Science.gov (United States)

    Imre, Ildikó; Tóth, Zsuzsanna

    2012-06-01

    During dental rehabilitation of a patient with ICD, an upper telescope retained overdenture with acrylic baseplate and lower cantilever bridges were constructed. In the consultation following the anamnesis and the clinical examination, the cardiologist did not believe antibiotic profilaxis to be necessary, adding that it is advisable to avoid the use of ultrasonic depurator and electrocauter. Nowadays after saving the life the improving of patient's better quality of life is an important aspect. The risk of ICD-implantation is minimal however, not negligible, the patient can pursue a way of life free of limitation. According to the latest trends, the number of ICD-implantations will increase exponentially in the near future, due to the aging of the population, the simplification and safeness of implantation and the increase of patients who can be treated with the device. In case of arritmia or putative dysfunction, the latest ICD-s are able to send emergency alert to the arritmia centre with the help of an outer transmitter. Probably the system will completely change the follow-up of patients with ICD within the next few years, clinical researches of its efficiency are going on at present.

  12. Implantable cardioverter defibrillator does not cure the heart.

    Science.gov (United States)

    Sławuta, Agnieszka; Boczar, Krzysztof; Ząbek, Andrzej; Gajek, Jacek; Lelakowski, Jacek; Vijayaraman, Pugazhendhi; Małecka, Barbara

    2018-01-23

    A man with non-ischemic cardiomyopathy, EF 22%, permanent AF and ICD was admitted for elective device replacement. The need for the optimization of the ventricular rate and avoidance of right ventricular pacing made it necessary to up-grade the existing pacing system using direct His bundle pacing and dual chamber ICD. This enabled the regularization of ventricular rate, avoiding the RV pacing and optimize the beta-blocker dose. The one month follow-up already showed reduction in left ventricle diameter, improvement in ejection fraction, NYHA class decrease to II. The His bundle pacing enabled the optimal treatment of the patient resulting in excellent clinical improvement.

  13. Phantom shocks in patients with implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Berg, Selina Kikkenborg; Moons, Philip; Zwisler, Ann-Dorthe

    2013-01-01

    of phantom shocks.METHODS AND RESULTS: The design was secondary explorative analyses of data from a randomized controlled trial. One hundred and ninety-six patients with first-time ICD implantation (79% male, mean age 58 years) were randomized (1 : 1) to either combined rehabilitation or a control group...... questions regarding the experience of phantom shocks, date, time, and place. Twelve patients (9.4%) experienced a phantom shock, 7 in the intervention group and 5 in the control group (NS). Neither age, sex, quality of life nor perceived health at baseline was significantly related to the probability...

  14. Pacemaker, implanted cardiac defibrillator and irradiation: Management proposal in 2010 depending on the type of cardiac stimulator and prognosis and location of cancer

    International Nuclear Information System (INIS)

    Lambert, P.; Da Costa, A.; Marcy, P.Y.; Kreps, S.; Angellier, G.; Marcie, S.; Bondiau, P.Y.; Briand-Amoros, C.; Thariat, J.

    2011-01-01

    Ionizing radiation may interfere with electric components of pacemakers or implantable cardioverter defibrillators. The type, severity and extent of radiation damage to pacemakers, have previously been shown to depend on the total dose and dose rate. Over 300,000 new cancer cases are treated yearly in France, among which 60% are irradiated in the course of their disease. One among 400 of these patients has an implanted pacemaker or defibrillator. The incidence of pacemaker and implanted cardioverter defibrillator increases in an ageing population. The oncologic prognosis must be weighted against the cardiologic prognosis in a multidisciplinary and transversal setting. Innovative irradiation techniques and technological sophistications of pacemakers and implantable cardioverter-defibrillators (with the introduction of more radiosensitive complementary metal-oxide-semiconductors since 1970) have potentially changed the tolerance profiles. This review of the literature studied the geometric, dosimetric and radiobiological characteristics of the radiation beams for high energy photons, stereotactic irradiation, proton-therapy. Standardized protocols and radiotherapy optimization (particle, treatment fields, energy) are advisable in order to improve patient management during radiotherapy and prolonged monitoring is necessary following radiation therapy. The dose received at the pacemaker/heart should be calculated. The threshold for the cumulated dose to the pacemaker/implantable cardioverter-defibrillator (2 to 5 Gy depending on the brand), the necessity to remove/displace the device based on the dose-volume histogram on dosimetry, as well as the use of lead shielding and magnet are discussed. (authors)

  15. Online cross-validation-based ensemble learning.

    Science.gov (United States)

    Benkeser, David; Ju, Cheng; Lendle, Sam; van der Laan, Mark

    2018-01-30

    Online estimators update a current estimate with a new incoming batch of data without having to revisit past data thereby providing streaming estimates that are scalable to big data. We develop flexible, ensemble-based online estimators of an infinite-dimensional target parameter, such as a regression function, in the setting where data are generated sequentially by a common conditional data distribution given summary measures of the past. This setting encompasses a wide range of time-series models and, as special case, models for independent and identically distributed data. Our estimator considers a large library of candidate online estimators and uses online cross-validation to identify the algorithm with the best performance. We show that by basing estimates on the cross-validation-selected algorithm, we are asymptotically guaranteed to perform as well as the true, unknown best-performing algorithm. We provide extensions of this approach including online estimation of the optimal ensemble of candidate online estimators. We illustrate excellent performance of our methods using simulations and a real data example where we make streaming predictions of infectious disease incidence using data from a large database. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  16. The NO Regular Defibrillation testing In Cardioverter Defibrillator Implantation (NORDIC ICD) trial

    DEFF Research Database (Denmark)

    Bänsch, Dietmar; Bonnemeier, Hendrik; Brandt, Johan

    2015-01-01

    was standardized across all participating centres. After inducing a fast ventricular tachycardia (VT) with a heart rate ≥240 b.p.m. or ventricular fibrillation (VF) with a low-energy T-wave shock, DF was attempted with an initial 15 J shock. If the shock reversed the VT or VF, DF testing was considered successful...... and terminated. If unsuccessful, two effective 24 J shocks were administered. If DF was unsuccessful, the system was reconfigured and another DF testing was performed. An ICD shock energy of 40 J had to be programmed in all patients for treatment of spontaneous VT/VF episodes. The primary endpoint...

  17. Automated External Defibrillator

    Science.gov (United States)

    ... leads to a 10 percent reduction in survival. Training To Use an Automated External Defibrillator Learning how to use an AED and taking a CPR (cardiopulmonary resuscitation) course are helpful. However, if trained ...

  18. Definition of successful defibrillation

    NARCIS (Netherlands)

    Koster, Rudolph W.; Walker, Robert G.; van Alem, Anouk P.

    2006-01-01

    OBJECTIVES: The definition of defibrillation shock "success" endorsed by the International Liaison Committee on Resuscitation since the publication of Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiac Care has been removal of ventricular fibrillation at 5 secs after shock

  19. Pacemaker, implanted cardiac defibrillator and irradiation: Management proposal in 2010 depending on the type of cardiac stimulator and prognosis and location of cancer; Pacemaker, defibrillateur et radiotherapie: propositions de conduite a tenir en 2010 en fonction du type de stimulateur cardiaque, du pronostic et du site du cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, P. [Service d' anesthesie reanimation, hopital Nord, centre hospitalier universitaire de Saint-etienne, 42055 Saint-etienne cedex 2 (France); Da Costa, A. [Service de cardiologie, hopital Nord, centre hospitalier universitaire de Saint-etienne, 42055 Saint-etienne cedex 2 (France); Marcy, P.Y. [Departement de radiologie, centre Antoine-Lacassagne, 33, avenue de Valombrose, 06189 Nice cedex 2 (France); Universite Nice Sophia-Antipolis, 33, avenue de Valombrose, 06189 Nice cedex 2 (France); Kreps, S. [Service de radiotherapie Corad, centre regional universitaire de cancerologie Henry-S.-Kaplan, hopital Bretonneau-2, CHU de Tours, boulevard Tonnelle, 37000 Tours (France); Angellier, G.; Marcie, S.; Bondiau, P.Y. [Universite Nice Sophia-Antipolis, 33, avenue de Valombrose, 06189 Nice cedex 2 (France); Departement de radiotherapie oncologie, centre CyberKnife, centre Antoine-Lacassagne, 33, avenue de Valombrose, 06189 Nice cedex 2 (France); Briand-Amoros, C. [Service de radiotherapie, hopital europeen Georges-Pompidou, 20, rue Leblanc, 75015 Paris (France); Thariat, J. [Universite Nice Sophia-Antipolis, 33, avenue de Valombrose, 06189 Nice cedex 2 (France); Departement de radiotherapie oncologie, centre CyberKnife, centre Antoine-Lacassagne, 33, avenue de Valombrose, 06189 Nice cedex 2 (France); IBDC CNRS UMR 6543, centre Antoine-Lacassagne, universite Sophia-Antipolis, 33, avenue de Valombrose, 06189 Nice cedex 2 (France)

    2011-06-15

    Ionizing radiation may interfere with electric components of pacemakers or implantable cardioverter defibrillators. The type, severity and extent of radiation damage to pacemakers, have previously been shown to depend on the total dose and dose rate. Over 300,000 new cancer cases are treated yearly in France, among which 60% are irradiated in the course of their disease. One among 400 of these patients has an implanted pacemaker or defibrillator. The incidence of pacemaker and implanted cardioverter defibrillator increases in an ageing population. The oncologic prognosis must be weighted against the cardiologic prognosis in a multidisciplinary and transversal setting. Innovative irradiation techniques and technological sophistications of pacemakers and implantable cardioverter-defibrillators (with the introduction of more radiosensitive complementary metal-oxide-semiconductors since 1970) have potentially changed the tolerance profiles. This review of the literature studied the geometric, dosimetric and radiobiological characteristics of the radiation beams for high energy photons, stereotactic irradiation, proton-therapy. Standardized protocols and radiotherapy optimization (particle, treatment fields, energy) are advisable in order to improve patient management during radiotherapy and prolonged monitoring is necessary following radiation therapy. The dose received at the pacemaker/heart should be calculated. The threshold for the cumulated dose to the pacemaker/implantable cardioverter-defibrillator (2 to 5 Gy depending on the brand), the necessity to remove/displace the device based on the dose-volume histogram on dosimetry, as well as the use of lead shielding and magnet are discussed. (authors)

  20. A cross-validation package driving Netica with python

    Science.gov (United States)

    Fienen, Michael N.; Plant, Nathaniel G.

    2014-01-01

    Bayesian networks (BNs) are powerful tools for probabilistically simulating natural systems and emulating process models. Cross validation is a technique to avoid overfitting resulting from overly complex BNs. Overfitting reduces predictive skill. Cross-validation for BNs is known but rarely implemented due partly to a lack of software tools designed to work with available BN packages. CVNetica is open-source, written in Python, and extends the Netica software package to perform cross-validation and read, rebuild, and learn BNs from data. Insights gained from cross-validation and implications on prediction versus description are illustrated with: a data-driven oceanographic application; and a model-emulation application. These examples show that overfitting occurs when BNs become more complex than allowed by supporting data and overfitting incurs computational costs as well as causing a reduction in prediction skill. CVNetica evaluates overfitting using several complexity metrics (we used level of discretization) and its impact on performance metrics (we used skill).

  1. Economic impact of longer battery life of cardiac resynchronization therapy defibrillators in Sweden

    Directory of Open Access Journals (Sweden)

    Gadler F

    2016-10-01

    Full Text Available Fredrik Gadler,1 Yao Ding,2 Nathalie Verin,3 Martin Bergius,4 Jeffrey D Miller,5 Gregory M Lenhart,5 Mason W Russell5 1Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden; 2Truven Health Analytics, an IBM Company, Bethesda, MD, USA; 3Boston Scientific Corporation, Hemel Hempstead, Hertfordshire, UK; 4Boston Scientific Nordic AB, Helsingborg, Sweden; 5Truven Health Analytics, an IBM Company, Cambridge, MA, USA Objective: The objective of this study was to quantify the impact that longer battery life of cardiac resynchronization therapy defibrillator (CRT-D devices has on reducing the number of device replacements and associated costs of these replacements from a Swedish health care system perspective.Methods: An economic model based on real-world published data was developed to estimate cost savings and avoided device replacements for CRT-Ds with longer battery life compared with devices with industry-standard battery life expectancy. Base-case comparisons were performed among CRT-Ds of three manufacturers – Boston Scientific Corporation, St. Jude Medical, and Medtronic – over a 6-year time horizon, as per the available clinical data. As a sensitivity analysis, we evaluated CRT-Ds as well as single-chamber implantable cardioverter defibrillator (ICD-VR and dual-chamber implantable cardioverter defibrillator (ICD-DR devices over a longer 10-year period. All costs were in 2015 Swedish Krona (SEK discounted at 3% per annum.Results: Base-case analysis results show that up to 603 replacements and up to SEK 60.4 million cumulative-associated costs could be avoided over 6 years by using devices with extended ­battery life. The pattern of savings over time suggests that savings are modest initially but increase rapidly beginning in the third year of follow-up with each year’s cumulative savings two to three times the previous year. Evaluating CRT-D, ICD-VR, and ICD-DR devices together over a longer 10-year period, the

  2. Public Access Defibrillation

    DEFF Research Database (Denmark)

    Agerskov, Marianne; Nielsen, Anne Møller; Hansen, Carolina Malta

    2015-01-01

    BACKGROUND: In Copenhagen, a volunteer-based Automated External Defibrillator (AED) network provides a unique opportunity to assess AED use. We aimed to determine the proportion of Out-of-Hospital Cardiac Arrest (OHCA) where an AED was applied before arrival of the ambulance, and the proportion o...

  3. Defibrillator Implantation in Patients with Nonischemic Systolic Heart Failure

    DEFF Research Database (Denmark)

    Køber, Lars; Thune, Jens J; Nielsen, Jens C

    2016-01-01

    Background The benefit of an implantable cardioverter-defibrillator (ICD) in patients with symptomatic systolic heart failure caused by coronary artery disease has been well documented. However, the evidence for a benefit of prophylactic ICDs in patients with systolic heart failure that is not due...... to coronary artery disease has been based primarily on subgroup analyses. The management of heart failure has improved since the landmark ICD trials, and many patients now receive cardiac resynchronization therapy (CRT). Methods In a randomized, controlled trial, 556 patients with symptomatic systolic heart.......6%) in the control group (P=0.29). Conclusions In this trial, prophylactic ICD implantation in patients with symptomatic systolic heart failure not caused by coronary artery disease was not associated with a significantly lower long-term rate of death from any cause than was usual clinical care. (Funded by Medtronic...

  4. Pacing and Defibrillators in Complex Congenital Heart Disease

    Science.gov (United States)

    Chubb, Henry; O’Neill, Mark; Rosenthal, Eric

    2016-01-01

    Device therapy in the complex congenital heart disease (CHD) population is a challenging field. There is a myriad of devices available, but none designed specifically for the CHD patient group, and a scarcity of prospective studies to guide best practice. Baseline cardiac anatomy, prior surgical and interventional procedures, existing tachyarrhythmias and the requirement for future intervention all play a substantial role in decision making. For both pacing systems and implantable cardioverter defibrillators, numerous factors impact on the merits of system location (endovascular versus non-endovascular), lead positioning, device selection and device programming. For those with Fontan circulation and following the atrial switch procedure there are also very specific considerations regarding access and potential complications. This review discusses the published guidelines, device indications and the best available evidence for guidance of device implantation in the complex CHD population. PMID:27403295

  5. [Electrical storm in patients with prophylactic defibrillator implantation].

    Science.gov (United States)

    Rodríguez-Mañero, Moisés; González-Cambeiro, Cristina; Moreno-Arribas, Jose; Expósito-García, Víctor; Sánchez-Gómez, Juan Miguel; González-Torres, Luis; Arce-León, Álvaro; Arguedas-Jiménez, Hugo; Gaztañaga, Larraitz; Salvador-Montañés, Oscar; Iglesias-Bravo, Jose Antonio; Huerta, Ana Andrés La; Fernández-Armenta, Juan; Arias, Miguel Ángel; Martínez-Sande, Luis

    2016-01-01

    Little is known about the prevalence of electrical storm, baseline characteristics and mortality implications of patients with implantable cardioverter defibrillator in primary prevention versus those patients without electrical storm. We sought to assess the prevalence, baseline risk profile and survival significance of electrical storm in patients with implantable defibrillator for primary prevention. Retrospective multicenter study performed in 15 Spanish hospitals. Consecutives patients referred for desfibrillator implantation, with or without left ventricular lead (at least those performed in 2010 and 2011), were included. Over all 1,174 patients, 34 (2,9%) presented an electrical storm, mainly due to ventricular tachycardia (82.4%). There were no significant baseline differences between groups, with similar punctuation in the mortality risk scores (SHOCKED, MADIT and FADES). A clear trigger was identified in 47% of the events. During the study period (38±21 months), long-term total mortality (58.8% versus 14.4%, pstorm patients. Rate of inappropriate desfibrillator intervention was also higher (14.7 versus 8.6%, pstorm was 2.9%. There were no baseline differences in the cardiovascular risk profile versus those without electrical storm. However, all cause mortality and cardiovascular mortality was increased in these patients versus control desfibrillator patients without electrical storm, as was the rate of inappropriate desfibrillator intervention. Copyright © 2015 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

  6. Benchmarking protein classification algorithms via supervised cross-validation

    NARCIS (Netherlands)

    Kertész-Farkas, A.; Dhir, S.; Sonego, P.; Pacurar, M.; Netoteia, S.; Nijveen, H.; Kuzniar, A.; Leunissen, J.A.M.; Kocsor, A.; Pongor, S.

    2008-01-01

    Development and testing of protein classification algorithms are hampered by the fact that the protein universe is characterized by groups vastly different in the number of members, in average protein size, similarity within group, etc. Datasets based on traditional cross-validation (k-fold,

  7. Integration of Attributes from Non-Linear Characterization of Cardiovascular Time-Series for Prediction of Defibrillation Outcomes.

    Directory of Open Access Journals (Sweden)

    Sharad Shandilya

    Full Text Available The timing of defibrillation is mostly at arbitrary intervals during cardio-pulmonary resuscitation (CPR, rather than during intervals when the out-of-hospital cardiac arrest (OOH-CA patient is physiologically primed for successful countershock. Interruptions to CPR may negatively impact defibrillation success. Multiple defibrillations can be associated with decreased post-resuscitation myocardial function. We hypothesize that a more complete picture of the cardiovascular system can be gained through non-linear dynamics and integration of multiple physiologic measures from biomedical signals.Retrospective analysis of 153 anonymized OOH-CA patients who received at least one defibrillation for ventricular fibrillation (VF was undertaken. A machine learning model, termed Multiple Domain Integrative (MDI model, was developed to predict defibrillation success. We explore the rationale for non-linear dynamics and statistically validate heuristics involved in feature extraction for model development. Performance of MDI is then compared to the amplitude spectrum area (AMSA technique.358 defibrillations were evaluated (218 unsuccessful and 140 successful. Non-linear properties (Lyapunov exponent > 0 of the ECG signals indicate a chaotic nature and validate the use of novel non-linear dynamic methods for feature extraction. Classification using MDI yielded ROC-AUC of 83.2% and accuracy of 78.8%, for the model built with ECG data only. Utilizing 10-fold cross-validation, at 80% specificity level, MDI (74% sensitivity outperformed AMSA (53.6% sensitivity. At 90% specificity level, MDI had 68.4% sensitivity while AMSA had 43.3% sensitivity. Integrating available end-tidal carbon dioxide features into MDI, for the available 48 defibrillations, boosted ROC-AUC to 93.8% and accuracy to 83.3% at 80% sensitivity.At clinically relevant sensitivity thresholds, the MDI provides improved performance as compared to AMSA, yielding fewer unsuccessful defibrillations

  8. Frequent Home Monitoring of ICD Is Effective to Prevent Inappropriate Defibrillator Shock Delivery

    Directory of Open Access Journals (Sweden)

    Paolo Bifulco

    2014-01-01

    Full Text Available Recently, in the context of telemedicine, telemonitoring services are gaining attention. They are offered, for example, to patients with implantable cardioverter defibrillators (ICDs. A major problem associated with ICD therapy is the occurrence of inappropriate shocks which impair patients’ quality of life and may also be arrhythmogenic. The telemonitoring can provide a valid support to intensify followup visits, in order to improve the prevention of inappropriate defibrillator shock, thus enhancing patient safety. Inappropriate shock generally depends on atrial fibrillation, supraventricular tachycardia, and abnormal sensing (such as those caused by electromagnetic interferences. As a practical example, an unusual case of an ICD patient who risked an inappropriate shock while taking a shower is reported. Continuous remote telemonitoring was able to timely warn cardiologist via GSM-SMS, who were able to detect improper sensing examining the intracardiac electrogram via Web. Patient was promptly contacted and warned to not further come in contact with the hydraulic system and any electrical appliance to prevent an inappropriate defibrillator shock. This demonstrates the effectiveness and usefulness of continuous remote telemonitoring in supporting ICD patients.

  9. Cross-Validation of Aerobic Capacity Prediction Models in Adolescents.

    Science.gov (United States)

    Burns, Ryan Donald; Hannon, James C; Brusseau, Timothy A; Eisenman, Patricia A; Saint-Maurice, Pedro F; Welk, Greg J; Mahar, Matthew T

    2015-08-01

    Cardiorespiratory endurance is a component of health-related fitness. FITNESSGRAM recommends the Progressive Aerobic Cardiovascular Endurance Run (PACER) or One mile Run/Walk (1MRW) to assess cardiorespiratory endurance by estimating VO2 Peak. No research has cross-validated prediction models from both PACER and 1MRW, including the New PACER Model and PACER-Mile Equivalent (PACER-MEQ) using current standards. The purpose of this study was to cross-validate prediction models from PACER and 1MRW against measured VO2 Peak in adolescents. Cardiorespiratory endurance data were collected on 90 adolescents aged 13-16 years (Mean = 14.7 ± 1.3 years; 32 girls, 52 boys) who completed the PACER and 1MRW in addition to a laboratory maximal treadmill test to measure VO2 Peak. Multiple correlations among various models with measured VO2 Peak were considered moderately strong (R = .74-0.78), and prediction error (RMSE) ranged from 5.95 ml·kg⁻¹,min⁻¹ to 8.27 ml·kg⁻¹.min⁻¹. Criterion-referenced agreement into FITNESSGRAM's Healthy Fitness Zones was considered fair-to-good among models (Kappa = 0.31-0.62; Agreement = 75.5-89.9%; F = 0.08-0.65). In conclusion, prediction models demonstrated moderately strong linear relationships with measured VO2 Peak, fair prediction error, and fair-to-good criterion referenced agreement with measured VO2 Peak into FITNESSGRAM's Healthy Fitness Zones.

  10. Cross-validated detection of crack initiation in aerospace materials

    Science.gov (United States)

    Vanniamparambil, Prashanth A.; Cuadra, Jefferson; Guclu, Utku; Bartoli, Ivan; Kontsos, Antonios

    2014-03-01

    A cross-validated nondestructive evaluation approach was employed to in situ detect the onset of damage in an Aluminum alloy compact tension specimen. The approach consisted of the coordinated use primarily the acoustic emission, combined with the infrared thermography and digital image correlation methods. Both tensile loads were applied and the specimen was continuously monitored using the nondestructive approach. Crack initiation was witnessed visually and was confirmed by the characteristic load drop accompanying the ductile fracture process. The full field deformation map provided by the nondestructive approach validated the formation of a pronounced plasticity zone near the crack tip. At the time of crack initiation, a burst in the temperature field ahead of the crack tip as well as a sudden increase of the acoustic recordings were observed. Although such experiments have been attempted and reported before in the literature, the presented approach provides for the first time a cross-validated nondestructive dataset that can be used for quantitative analyses of the crack initiation information content. It further allows future development of automated procedures for real-time identification of damage precursors including the rarely explored crack incubation stage in fatigue conditions.

  11. Cross-validating a bidimensional mathematics anxiety scale.

    Science.gov (United States)

    Haiyan Bai

    2011-03-01

    The psychometric properties of a 14-item bidimensional Mathematics Anxiety Scale-Revised (MAS-R) were empirically cross-validated with two independent samples consisting of 647 secondary school students. An exploratory factor analysis on the scale yielded strong construct validity with a clear two-factor structure. The results from a confirmatory factor analysis indicated an excellent model-fit (χ(2) = 98.32, df = 62; normed fit index = .92, comparative fit index = .97; root mean square error of approximation = .04). The internal consistency (.85), test-retest reliability (.71), interfactor correlation (.26, p anxiety. Math anxiety, as measured by MAS-R, correlated negatively with student achievement scores (r = -.38), suggesting that MAS-R may be a useful tool for classroom teachers and other educational personnel tasked with identifying students at risk of reduced math achievement because of anxiety.

  12. Atrial therapies reduce atrial arrhythmia burden in defibrillator patients.

    Science.gov (United States)

    Friedman, P A; Dijkman, B; Warman, E N; Xia, H A; Mehra, R; Stanton, M S; Hammill, S C

    2001-08-28

    Approximately 25% of patients who receive an implantable cardioverter-defibrillator (ICD) to treat ventricular tachyarrhythmias have documented atrial tachyarrhythmias before implantation. This study assessed the ability of device-based prevention and termination therapies to reduce the burden of spontaneous atrial tachyarrhythmias. Patients with a standard indication for the implantation of an ICD and 2 episodes of atrial tachyarrhythmias in the preceding year received a dual-chamber ICD (Medtronic 7250 Jewel AF) that uses pacing and shock therapies for prevention and/or termination of atrial tachyarrhythmias. In a multicenter trial, patients were randomized to 3-month periods with atrial therapies "on" or "off" and subsequently crossed over. Analysis was performed on the 52 of 269 patients who had episodes of atrial tachyarrhythmia and had >/=30 days of follow-up with atrial therapies on and off. The atrial therapies resulted in a reduction of atrial tachyarrhythmia burden from a mean of 58.5 to 7.8 h/mo. A paired analysis (Wilcoxon signed-rank test) showed that the median difference in burden (1.1 h/mo) was highly significant (P=0.007). When the subgroup of 41 patients treated only with atrial pacing therapies was analyzed, the reduction in burden persisted (P=0.01). In this study, patients with a standard ICD indication and atrial tachyarrhythmias had a significant reduction in atrial tachyarrhythmia burden with use of atrial pacing and shock therapies.

  13. Inverse Relation between Condition of Heart Failure and Intrathoracic Impedance Measured by Implantable Cardioverter Defibrillator—A case report—

    Directory of Open Access Journals (Sweden)

    Kohei Matsushita, MD

    2005-01-01

    Full Text Available The patient was a 78-year-old man with dilated cardiomyopathy. His cardio-thoracic ratio was 60.4% and left ventricular ejection fraction (LVEF was 33%. He had been repeatedly admitted for congestive heart failure. He underwent implantation of an implantable cardioverter-defibrillator (ICD for ventricular fibrillation. We compared the values of BNP and shock impedance stored by the ICD. The correlation coefficient (p-value between BNP and shock impedance was −0.700 (p < 0.0005, increase of BNP and shock impedance was −0.778 (p < 0.0001, percent increase of BNP and shock impedance was −0.767 (p < 0.0005. In conclusion, there is an inverse relation between BNP and shock impedance, and measurements of shock impedance may be useful in the management of congestive heart failure.

  14. [Septic shock due to infective endocarditis of stimulation system of implantable cardioverter-defibrillator].

    Science.gov (United States)

    Porubčinová, I; Porubčin, S; Stančák, B; Beňa, M; Sabol, F

    2012-01-01

    We present a case of a 60-year old patient hospitalized at the Department of Infectious Diseases and Travel Medicine, Medical faculty of UPJS and L. Pasteurs University Hospital in Kosice with suspected gastroenteritis. The patient was admitted to an intensive care unit because of the signs of septic shock. Within one hour from admission, the patient was administered early goal directed therapy for septic shock. Subsequently, infectious endocarditis of stimulation electrodes and tricuspid valve was identified as the origin of the infection. The stimulation system was then explanted from a stabilized and afebrile patient at the Department of cardiac Surgery of Eastern Slovak Institute of Cardiac and Vascular Diseases in Kosice. This case should emphasise frequently atypical course of this serious disease and the need for early identification of severe sepsis to enable timely management to affect mortality.

  15. Emotional distress in partners of patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Van Den Broek, Krista C; Habibović, Mirela; Pedersen, Susanne S.

    2010-01-01

    on psychological distress in partners of ICD patients and recommendations for future research. PubMed and PsycInfo were searched in March 2010 using a priori defined search terms. This search and the additional hand search resulted in 22 studies, of which 13 were quantitative and eight qualitative. Sample sizes...... studies reported no impact of ICD shocks on distress levels or quality of life in partners. ICD indication as well as comorbid conditions, age, and the psychological profile of the partner were related to distress and quality of life. Domains of concern emerging from qualitative studies were related...... to care of the ICD patient, helplessness and uncertainties related to shocks, role changes, sexual activities, overprotectiveness, and driving. Partner levels of distress may be as high as that of ICD patients. Research with large samples is needed to further investigate the course and determinants...

  16. Low disease prevalence and inappropriate implantable cardioverter defibrillator shock rate in Brugada syndrome

    DEFF Research Database (Denmark)

    Holst, Anders Gaarsdal; Jensen, Henrik Kjærulf; Eschen, Ole

    2012-01-01

    AimsBrugada syndrome (BrS) is an inherited channelopathy that predisposes to malignant ventricular arrhythmias and thereby syncope and sudden cardiac death. Prior studies characterizing BrS patients have used highly selected referral populations from tertiary centres and prevalence estimates have...... been carried out using electrocardiogram (ECG) surveys only. We aimed to identify and characterize all diagnosed BrS patients in Denmark (population 5.4 million).Methods and resultsBrugada syndrome patients were identified using several modalities including identification in all Danish tertiary......%) experienced inappropriate shocks during a median follow-up of 47 months. No patient died or experienced aborted sudden cardiac death during follow-up.ConclusionsWe report the first nationwide study of BrS patients. We found a low incidence of diagnosed definite BrS compared with estimates from ECG surveys...

  17. Inappropriate implantable cardioverter-defibrillator shocks in Brugada syndrome: Pattern in primary and secondary prevention

    Directory of Open Access Journals (Sweden)

    Aimé Bonny

    2017-01-01

    Conclusion: Inappropriate shock is common in Brugada syndrome during the early periods after an ICD implantation, and seems to be more likely in asymptomatic patients. This finding may warrant a review of the indications for ICD implantation, especially in the young and apparently healthy population of patients with Brugada syndrome.

  18. Poor perceived social support in implantable cardioverter defibrillator (ICD) patients and their partners

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; Spinder, Helle; Erdman, Ruud A M

    2009-01-01

    Social support is a known buffer of psychological distress and has also been shown to influence adverse medical outcomes.......Social support is a known buffer of psychological distress and has also been shown to influence adverse medical outcomes....

  19. Clinical effects and implications of cardiac rehabilitation for implantable cardioverter defibrillator patients

    DEFF Research Database (Denmark)

    Berg, Selina Kikkenborg; Moons, Philip; Christensen, Anne Vingaard

    2015-01-01

    rehabilitation and usual care was found in physical capacity and general and mental health. However, the clinical effect sizes of these findings were not investigated, and the findings from the quantitative and qualitative analyses were not triangulated to address the issue of whether the qualitative results...... could help explain the quantitative results and bring forward additional information. OBJECTIVES:: The objectives are to (a) determine the clinical effect sizes of the primary outcomes and (b) triangulate the quantitative and qualitative findings. METHODS:: A total of 196 patients with first...... d was calculated. Qualitative interviews were conducted with 10 patients representing the rehabilitation group. Triangulation was carried out by integrating the findings from the quantitative and qualitative results in light of each other. RESULTS:: Clinically meaningful effects were found between...

  20. Implantable cardioverter defibrillators in the context of hypertrophic cardiomyopathy: a lesson in patient autonomy.

    Science.gov (United States)

    Bray, Jonathan James Hyett; Bucciarelli-Ducci, Chiara; Stuart, Graham

    2018-02-05

    Hypertrophiccardiomyopathy (HCM) is common, whereas the decision not to have an implantable cardioverterdefibrillator (ICD) when probably falling into a 'high-risk' category is not. A solicitor aged 45 years attended the inherited cardiac conditions clinic for review of her HCM and discussion about ICD implantation for primary prevention of sudden cardiac death (SCD). Despite a predicted 7% risk of SCD within the next 5 years, according to the European Society of Cardiology endorsed HCM Risk-SCD risk stratification tool, the patient opted against implantation of an ICD and comprehensively justifies her decision. This report discusses ethical aspects of a consultation offering ICD protection against SCD in the context of HCM and emphasises the clinicians' role in respecting patient autonomy. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Effects of an alert system on implantable cardioverter defibrillator-related anxiety

    DEFF Research Database (Denmark)

    Duru, Firat; Dorian, Paul; Favale, Stefano

    2010-01-01

    failing to receive needed therapy for the same reason. New devices include programmable vibrating patient notifiers (PN), which, by warning patients of a possible device dysfunction, might lower device-related anxiety. PAtient NOtifier feature for Reduction of Anxiety: a Multicentre ICD study (PANORAMIC......) is a multicentre, randomized, clinical trial designed to examine the effects of the awareness of an active vibrating alert system on device-related anxiety....

  2. Quality of Life and Psychological Factors in Patients with Implantable Cardioverter Defibrillator

    Directory of Open Access Journals (Sweden)

    Akiko Suyama-Chishaki, MD PhD

    2007-01-01

    CONCLUSION: To support ICD recipients both physically and mentally, not only the cardiologists but also specialists from other fields such as psychologists and nurse specialists are needed. Ancillary care must be provided through the support team. Cardiologists who determine whether ICD implantation is required must keep in mind potential psychological sequelae.

  3. Shock as a determinant of poor patient-centered outcomes in implantable cardioverter defibrillator patients

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; Van Den Broek, Krista C; Van Den Berg, Martha

    2010-01-01

    as an outcome, and compare the influence of ICD shock with other factors (e.g., heart failure and psychological factors) as determinants of outcomes, with a view to providing recommendations for clinical practice and future research. Based on the large-scale primary and secondary prevention trials (i.e., CABG......-PATCH, CIDS, AVID, AMIOVIRT, SCD-HeFT, MADIT-II, and DEFINITE), evidence for an association between ICD shocks and quality of life is mixed, with some indication that the influence of shocks may depend largely on the interval between shocks and assessment of quality of life. In order to improve the clinical...... management of ICD patients, we need to adopt a more rigorous and standardized methodology in future studies in order to be able to draw firm conclusions about the impact of ICD shocks on individual patients. We also need to acknowledge that the impact of shocks on psychological functioning and quality...

  4. Merits and limitations of the mode switching rate stabilization pacing algorithms in the implantable cardioverter defibrillator.

    Science.gov (United States)

    Dijkman, B; Wellens, H J

    2001-09-01

    The 7250 Jewel AF Medtronic model of ICD is the first implantable device in which both therapies for atrial arrhythmias and pacing algorithms for atrial arrhythmia prevention are available. Feasibility of that extensive atrial arrhythmia management requires correct and synergic functioning of different algorithms to control arrhythmias. The ability of the new pacing algorithms to stabilize the atrial rate following termination of treated atrial arrhythmias was evaluated in the marker channel registration of 600 spontaneously occurring episodes in 15 patients with the Jewel AF. All patients (55+/-15 years) had structural heart disease and documented atrial and ventricular arrhythmias. Dual chamber rate stabilization pacing was present in 245 (41 %) of episodes following arrhythmia termination and was a part of the mode switching operation during which pacing was provided in the dynamic DDI mode. This algorithm could function as the atrial rate stabilization pacing only when there was a slow spontaneous atrial rhythm or in presence of atrial premature beats conducted to the ventricles with a normal AV time. In case of atrial premature beats with delayed or absent conduction to the ventricles and in case of ventricular premature beats, the algorithm stabilized the ventricular rate. The rate stabilization pacing in DDI mode during sinus rhythm following atrial arrhythmia termination was often extended in time due to the device-based definition of arrhythmia termination. This was also the case in patients, in whom the DDD mode with true atrial rate stabilization algorithm was programmed. The rate stabilization algorithms in the Jewel AF applied after atrial arrhythmia termination provide pacing that is not based on the timing of atrial events. Only under certain circumstances the algorithm can function as atrial rate stabilization pacing. Adjustments in availability and functioning of the rate stabilization algorithms might be of benefit for the clinical performance of pacing as part of device therapy for atrial arrhythmias.

  5. Long-term mortality risk in patients with an implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Theuns, Dominic A M J; Pedersen, Susanne S.

    2014-01-01

    .9)). The impact of heart rate and QRS duration on time to all-cause mortality was separately assessed with Cox proportional hazard regression analysis, adjusting for clinical factors and symptoms of depression and anxiety. RESULTS: Mean (SD) heart rate was 68.0 ± 13.3 bpm and mean QRS duration was 130.9 ± 36.9 ms....... Heart rate of ≥80 bpm was associated with increased risk of mortality (HR=1.86; 95% CI=1.15-3.00; p=.011) in unadjusted analysis. In adjusted analyses, this relationship remained significant both with depression (HR=1.86, 95% CI=1.12-3.09; p=.017) and anxiety (HR=1.82, 95% CI=1.10-3.03; p=.021...

  6. Long-term survival of implantable cardioverter defibrillator recipients with end-stage renal disease

    Directory of Open Access Journals (Sweden)

    Mikhael F. El-Chami, MD, FACC, FHRS

    2017-10-01

    Conclusion: ESRD patients are at significantly increased risk of mortality as compared with a non-dialysis cohort. While the majority of these patients survive more than one year post-diagnosis, the three-year mortality is high (43%. Randomized studies addressing the benefits of ICDs in ESRD patients are needed to better define their value for primary prevention of SCD.

  7. Intensity of primary emotions in patients after implantation of an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Stoier, Louise; Pedersen, Preben Ulrich; Berg, Selina Kikkenborg

    2013-01-01

    -November 2009. A total number of 154 patients were needed in the trial. The data collected were compared with secondary data from patients who had recently suffered a Myocardial Infarction and from a healthy population. SPSS version 18.0 was used to analyze the data using t-test, chisquare and F...

  8. Failure to Treat Life-Threatening Ventricular Tachyarrhythmias in Contemporary Implantable Cardioverter-Defibrillators

    DEFF Research Database (Denmark)

    Thøgersen, Anna Margrethe; Larsen, Jacob Moesgaard; Johansen, Jens Brock

    2017-01-01

    . CONCLUSIONS: Complex and unanticipated interactions between manufacturer-specific features and generic programming can prevent therapy for VF. More data are needed to assess the risks and benefits of translating evidence-based detection parameters from one manufacturer to another....

  9. Long-Term Evaluation of Biotronik Linox and Linox(smart) Implantable Cardioverter Defibrillator Leads.

    Science.gov (United States)

    Good, Eric D; Cakulev, Ivan; Orlov, Michael V; Hirsh, David; Simeles, John; Mohr, Kelly; Moll, Phil; Bloom, Heather

    2016-06-01

    Expert consensus holds that post-market, systematic surveillance of ICD leads is essential to ensure confirmation of adequate lead performance. GALAXY (NCT00836589) and CELESTIAL (NCT00810264) are ongoing multicenter, prospective, non-randomized registries conducted to confirm the long-term safety and reliability of Biotronik leads. ICD and CRT-D patients are followed for Linox and Linox(smart) ICD lead performance and safety for 5 years post-implant. All procedural and system-related adverse events (AEs) were assessed at each follow-up, along with lead electrical parameters. An independent CEC of EPs adjudicated AEs to determine AE category and lead relatedness. The analysis used categories of lead observations per ISO 5841-2 (Third edition). A total of 3,933 leads were implanted in 3,840 patients (73.0% male, mean age 67.0 ± 12.2 years) at 146 US centers. The estimated cumulative survival probability was 96.3% at 5 years after implant for Linox leads and 96.6% at 4 years after implant for Linox(smart) leads. A comparison of the Linox and Linox(smart) survival functions did not find evidence of a difference (P = 0.2155). The most common AEs were oversensing (23, 0.58%), conductor fracture (14, 0.36%), failure to capture (13, 0.33%), lead dislodgement (12, 0.31%), insulation breach (10, 0.25%), and abnormal pacing impedance (8, 0.20%). Linox and Linox(smart) ICD leads are safe, reliable and infrequently associated with lead-related AEs. Additionally, estimated cumulative survival probability is clinically acceptable and well within industry standards. Ongoing data collection will confirm the longer-term safety and performance of the Linox family of ICD leads. © 2016 Wiley Periodicals, Inc.

  10. Coping with Trauma and Stressful Events As a Patient with an Implantable Cardioverter-Defibrillator

    Science.gov (United States)

    ... Circulation My alerts Sign In Join Sign out Facebook Twitter Home About this Journal Editorial Board General Statistics Circulation Doodle Information for Advertisers Author Reprints Commercial Reprints Customer Service and Ordering ...

  11. Clinical and psychological impact of prophylactic implantable cardioverter-defibrillators in a community heart failure population.

    LENUS (Irish Health Repository)

    Arnous, S

    2012-02-01

    AIMS: ICD implantation for primary prevention of sudden cardiac death in patients with left ventricular systolic dysfunction (ejection fraction <\\/= 35%) has increased since the publication of the SCD-HEFT and MADIT-II data. The aim of this study is to examine the effectiveness and safety of prophylactic ICD use in a community heart failure population and to assess the impact on patient\\'s quality of life. METHODS AND RESULTS: Seventy-one ICDs were inserted between the years 2002 and 2006. The mean follow-up from time of insertion was 24 +\\/- 11 months. Eighteen patients (25%) had potentially life-saving therapy. Seven (10%) patients received inappropriate shocks. Complications were encountered in five patients (7%). CONCLUSION: In a community heart failure population, prophylactic ICD implantation is associated with a high incidence of life-saving therapy, a low complication rate and a high level of tolerability. These data indicate translation of clinical trial benefits to the general heart failure population.

  12. Relation of statin therapy to psychological functioning in patients with an implantable cardioverter defibrillator

    NARCIS (Netherlands)

    Hoogwegt, M.T.; Theuns, D.A.M.J.; Kupper, N.; Jordaens, L.; Pedersen, S.S.

    2013-01-01

    Statin therapy is an important secondary prevention measure in cardiovascular disease. However, the side effects associated with statin use could potentially affect patients' quality of life. Little is known about the influence of statin therapy on the well-being and health status of cardiac

  13. My Child Needs or Has an Implantable Cardioverter-Defibrillator: What Should I Do?

    Science.gov (United States)

    ... al. 7 How Can We Boost My Child's Self-Esteem? No matter what the age, a fun way ... to treatment among children with cardiac disease . Cardiol Young . 2009 ; 19 : 545 – 551 . OpenUrl CrossRef PubMed 3. ↵ ...

  14. 77 FR 20873 - Qualification of Drivers; Application for Exemptions; Implantable Cardioverter Defibrillators

    Science.gov (United States)

    2012-04-06

    ..., please include a self-addressed, stamped envelope or postcard or print the acknowledgement page that... variety known to be accompanied by syncope, dyspnea, collapse, or congestive cardiac failure. FMCSA..., collapse or congestive cardiac failure; and/or (2) which is likely to cause syncope, dyspnea, collapse, or...

  15. Sex differences in outcomes of primary prevention implantable cardioverter defibrillator therapy

    DEFF Research Database (Denmark)

    Sticherling, Christian; Arendacka, Barbora; Svendsen, Jesper Hastrup

    2018-01-01

    measures were overall mortality and first appropriate and first inappropriate shocks. A multivariable model enforcing a common hazard ratio for sex category across the centres, but allowing for centre-specific baseline hazards and centre specific effects of other covariates, was adjusted for age...

  16. Comprehensive cardiac rehabilitation improves outcome for patients with implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Berg, Selina Kikkenborg; Pedersen, Preben Ulrich; Zwisler, Ann-Dorthe

    2015-01-01

    year of psycho-educational follow-up focusing on modifiable factors associated with poor outcomes. Two primary outcomes, general health score (Short Form-36 (SF-36)) and peak oxygen uptake (VO2), were used. Post-hoc analyses included SF-36 and ICD therapy history.Results:Comprehensive cardiac...

  17. Arrhythmogenic Right Ventricular Cardiomyopathy: Risk Stratification and Indications for Defibrillator Therapy.

    Science.gov (United States)

    Zorzi, Alessandro; Rigato, Ilaria; Bauce, Barbara; Pilichou, Kalliopi; Basso, Cristina; Thiene, Gaetano; Iliceto, Sabino; Corrado, Domenico

    2016-06-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetically determined disease which predisposes to life-threatening ventricular arrhythmias. The main goal of ARVC therapy is prevention of sudden cardiac death (SCD). Implantable cardioverter defibrillator (ICD) is the most effective therapy for interruption of potentially lethal ventricular tachyarrhythmias. Despite its life-saving potential, ICD implantation is associated with a high rate of complications and significant impact on quality of life. Accurate risk stratification is needed to identify individuals who most benefit from the therapy. While there is general agreement that patients with a history of cardiac arrest or hemodynamically unstable ventricular tachycardia are at high risk of SCD and needs an ICD, indications for primary prevention remain a matter of debate. The article reviews the available scientific evidence and guidelines that may help to stratify the arrhythmic risk of ARVC patients and guide ICD implantation. Other therapeutic strategies, either alternative or additional to ICD, will be also addressed.

  18. Cross validation for the classical model of structured expert judgment

    International Nuclear Information System (INIS)

    Colson, Abigail R.; Cooke, Roger M.

    2017-01-01

    We update the 2008 TU Delft structured expert judgment database with data from 33 professionally contracted Classical Model studies conducted between 2006 and March 2015 to evaluate its performance relative to other expert aggregation models. We briefly review alternative mathematical aggregation schemes, including harmonic weighting, before focusing on linear pooling of expert judgments with equal weights and performance-based weights. Performance weighting outperforms equal weighting in all but 1 of the 33 studies in-sample. True out-of-sample validation is rarely possible for Classical Model studies, and cross validation techniques that split calibration questions into a training and test set are used instead. Performance weighting incurs an “out-of-sample penalty” and its statistical accuracy out-of-sample is lower than that of equal weighting. However, as a function of training set size, the statistical accuracy of performance-based combinations reaches 75% of the equal weight value when the training set includes 80% of calibration variables. At this point the training set is sufficiently powerful to resolve differences in individual expert performance. The information of performance-based combinations is double that of equal weighting when the training set is at least 50% of the set of calibration variables. Previous out-of-sample validation work used a Total Out-of-Sample Validity Index based on all splits of the calibration questions into training and test subsets, which is expensive to compute and includes small training sets of dubious value. As an alternative, we propose an Out-of-Sample Validity Index based on averaging the product of statistical accuracy and information over all training sets sized at 80% of the calibration set. Performance weighting outperforms equal weighting on this Out-of-Sample Validity Index in 26 of the 33 post-2006 studies; the probability of 26 or more successes on 33 trials if there were no difference between performance

  19. Use of Automated External Defibrillators

    Energy Technology Data Exchange (ETDEWEB)

    Gregory K Christensen

    2009-02-01

    In an effort to improve survival from cardiac arrest, the American Heart Association (AHA) has promoted the Chain of Survival concept, describing a sequence of prehospital steps that result in improved survival after sudden cardiac arrest. These interventions include immediate deployment of emergency medical services, prompt cardiopulmonary resuscitation, early defibrillation when indicated, and early initiation of advanced medical care. Early defibrillation has emerged as the most important intervention with survival decreasing by 10% with each minute of delay in defibrillation. Ventricular Fibrillation (VF) is a condition in which there is uncoordinated contraction of the heart cardiac muscle of the ventricles in the heart, making them tremble rather than contract properly. VF is a medical emergency and if the arrhythmia continues for more than a few seconds, blood circulation will cease, and death can occur in a matter of minutes. During VF, contractions of the heart are not synchronized, blood flow ceases, organs begin to fail from oxygen deprivation and within 10 minutes, death will occur. When VF occurs, the victim must be defibrillated in order to establish the heart’s normal rhythm. On average, the wait for an ambulance in populated areas of the United States is about 11 minutes. In view of these facts, the EFCOG Electrical Safety Task Group initiated this review to evaluate the potential value of deployment and use of automated external defibrillators (AEDs) for treatment of SCA victims. This evaluation indicates the long term survival benefit to victims of SCA is high if treated with CPR plus defibrillation within the first 3-5 minutes after collapse. According to the American Heart Association (AHA), survival rates as high as 74% are possible if treatment and defibrillation is performed in the first 3 minutes. In contrast survival rates are only 5% where no AED programs have been established to provide prompt CPR and defibrillation. ["CPR statistics

  20. Cross-validation pitfalls when selecting and assessing regression and classification models.

    Science.gov (United States)

    Krstajic, Damjan; Buturovic, Ljubomir J; Leahy, David E; Thomas, Simon

    2014-03-29

    We address the problem of selecting and assessing classification and regression models using cross-validation. Current state-of-the-art methods can yield models with high variance, rendering them unsuitable for a number of practical applications including QSAR. In this paper we describe and evaluate best practices which improve reliability and increase confidence in selected models. A key operational component of the proposed methods is cloud computing which enables routine use of previously infeasible approaches. We describe in detail an algorithm for repeated grid-search V-fold cross-validation for parameter tuning in classification and regression, and we define a repeated nested cross-validation algorithm for model assessment. As regards variable selection and parameter tuning we define two algorithms (repeated grid-search cross-validation and double cross-validation), and provide arguments for using the repeated grid-search in the general case. We show results of our algorithms on seven QSAR datasets. The variation of the prediction performance, which is the result of choosing different splits of the dataset in V-fold cross-validation, needs to be taken into account when selecting and assessing classification and regression models. We demonstrate the importance of repeating cross-validation when selecting an optimal model, as well as the importance of repeating nested cross-validation when assessing a prediction error.

  1. CVTresh: R Package for Level-Dependent Cross-Validation Thresholding

    Directory of Open Access Journals (Sweden)

    Donghoh Kim

    2006-04-01

    Full Text Available The core of the wavelet approach to nonparametric regression is thresholding of wavelet coefficients. This paper reviews a cross-validation method for the selection of the thresholding value in wavelet shrinkage of Oh, Kim, and Lee (2006, and introduces the R package CVThresh implementing details of the calculations for the procedures. This procedure is implemented by coupling a conventional cross-validation with a fast imputation method, so that it overcomes a limitation of data length, a power of 2. It can be easily applied to the classical leave-one-out cross-validation and K-fold cross-validation. Since the procedure is computationally fast, a level-dependent cross-validation can be developed for wavelet shrinkage of data with various sparseness according to levels.

  2. CVTresh: R Package for Level-Dependent Cross-Validation Thresholding

    Directory of Open Access Journals (Sweden)

    Donghoh Kim

    2006-04-01

    Full Text Available The core of the wavelet approach to nonparametric regression is thresholding of wavelet coefficients. This paper reviews a cross-validation method for the selection of the thresholding value in wavelet shrinkage of Oh, Kim, and Lee (2006, and introduces the R package CVThresh implementing details of the calculations for the procedures.This procedure is implemented by coupling a conventional cross-validation with a fast imputation method, so that it overcomes a limitation of data length, a power of 2. It can be easily applied to the classical leave-one-out cross-validation and K-fold cross-validation. Since the procedure is computationally fast, a level-dependent cross-validation can be developed for wavelet shrinkage of data with various sparseness according to levels.

  3. A second defibrillator chest patch electrode will increase implantation rates for nonthoracotomy defibrillators.

    Science.gov (United States)

    Solomon, A J; Swartz, J F; Rodak, D J; Moore, H J; Hannan, R L; Tracy, C M; Fletcher, R D

    1996-09-01

    Nonthoracotomy defibrillator systems can be implanted with a lower morbidity and mortality, compared to epicardial systems. However, implantation may be unsuccessful in up to 15% of patients, using a monophasic waveform. It was the purpose of this study to prospectively examine the efficacy of a second chest patch electrode in a nonthoracotomy defibrillator system. Fourteen patients (mean age 62 +/- 11 years, ejection fraction = 0.29 +/- 0.12) with elevated defibrillation thresholds, defined as > or = 24 J, were studied. The initial lead system consisted of a right ventricular electrode (cathode), a left innominate vein, and subscapular chest patch electrode (anodes). If the initial defibrillation threshold was > or = 24 J, a second chest patch electrode was added. This was placed subcutaneously in the anterior chest (8 cases), or submuscularly in the subscapular space (6 cases). This resulted in a decrease in the system impedance at the defibrillation threshold, from 72.3 +/- 13.3 omega to 52.2 +/- 8.6 omega. Additionally, the defibrillation threshold decreased from > or = 24 J, with a single patch, to 16.6 +/- 2.8 J with two patches. These changes were associated with successful implantation of a nonthoracotomy defibrillator system in all cases. In conclusion, the addition of a second chest patch electrode (using a subscapular approach) will result in lower defibrillation thresholds in patients with high defibrillation thresholds, and will subsequently increase implantation rates for nonthoracotomy defibrillators.

  4. Cross validation of bioelectrical impedance equations for men

    Directory of Open Access Journals (Sweden)

    Maria Fátima Glaner

    2005-06-01

    Full Text Available The purpose of this study was to analyze the cross validity of bioimpedance equations (BIA on the estimation of the fat free mass (FFM of 44 men, with mean age of 24.98 ± 3.40 years and relative body fat (%BF of 17.15 ± 6.41%. A dual energy x-ray absorptiometry was used as a reference method for %BF and FFM. Total body resistance was assessed by the Biodynamics (Model 310. The equations analyzed in this study were: two equations (Eq.1 and 2 developed by Carvalho e Pires Neto (1998; one equation (Eq. 3 developed by Rising et al.(1991; one equation (Eq. 4 developed by Oppliger et al.(1991; two equations (Eq. 5 (%FM RESUMO Este estudo teve como objetivo analisar a validade concorrente de equações de impedância bioelétrica (IB para estimar a massa corporal livre de gordura (MLG, em 44 homens, com idade média de 24,98 ± 3,40 anos e gordura relativa (%G de 17,15 ± 6,41 %. A absortometria de raio-x de dupla energia foi usada como critério, para mensurar a %G e a MLG, e para obter estas variáveis decorrentes das equações de IB foi utilizado o Biodynamics (Modelo 310. As equações de IB analisadas neste estudo foram: duas equações (Eq. 1 e 2 de Carvalho e Pires Neto (1998; uma equação (Eq. 3 de Rising et al. (1991; uma equação (Eq. 4 de Oppliger et al.(1991; duas equações (Eq. 5 (%G < 20% e Eq. 6 (%G ≥ 20% de Segal et al. (1988. Os critérios adotados para validação foram os propostos por Lohman (1991. Todas as correlações foram altas e significativas, oscilando de 0,906 (Eq. 2 a 0,981 (Eq. 6. As equações 1 a 5 superestimaram de forma significativa (p < 0,001 a MLG, sendo que os erros constantes variaram de 1,32 kg (Eq. 5 a 5,90 kg (Eq. 4. A equação 6 atendeu a todos os critérios de validação, apresentando: correlação = 0,981; erro constante = -0,38 kg; erro total = 1,10 kg. Esta equação de Segal et al.(1988, para homens com gordura relativa ≥ 20% (Eq. 6 foi a única que apresentou validade concorrente, estimando

  5. Bayesian leave-one-out cross-validation approximations for Gaussian latent variable models

    DEFF Research Database (Denmark)

    Vehtari, Aki; Mononen, Tommi; Tolvanen, Ville

    2016-01-01

    The future predictive performance of a Bayesian model can be estimated using Bayesian cross-validation. In this article, we consider Gaussian latent variable models where the integration over the latent values is approximated using the Laplace method or expectation propagation (EP). We study...... the properties of several Bayesian leave-one-out (LOO) cross-validation approximations that in most cases can be computed with a small additional cost after forming the posterior approximation given the full data. Our main objective is to assess the accuracy of the approximative LOO cross-validation estimators...

  6. Interaction of defibrillation waveform with the time to defibrillation or the number of defibrillation attempts on survival from out-of-hospital cardiac arrest.

    Science.gov (United States)

    Hagihara, Akihito; Onozuka, Daisuke; Ono, Junko; Nagata, Takashi; Hasegawa, Manabu

    2018-01-01

    Early biphasic defibrillation is effective in out-of-hospital cardiac arrest (OHCA) cases. In the resuscitation of patients with OHCA, it is not clear how the defibrillation waveform interacts with the time to defibrillation to influence patient survival. The second, and any subsequent, shocks need to be administered by an on-line physician in Japan. Thus, we investigated the interaction between the defibrillation waveform and time to or the number of defibrillation on resuscitation outcomes. This prospective observational study used data for all OHCAs that occurred between 2005 and 2014 in Japan. To investigate the interaction effect between the defibrillation waveform and the time to defibrillation or the number of defibrillations on the return to spontaneous circulation (ROSC), 1-month survival, and cerebral performance category (CPC) (1, 2), we assessed the modifying effects of the defibrillation waveform and the time to or the number of defibrillation on additive scale (i.e., the relative excessive risk due to interaction, RERI) and multiplicative scale (i.e., ratio of odds ratios (ORs)). In total, 71,566 cases met the inclusion criteria. For the measure of interaction between the defibrillation waveform and the time to defibrillation, ratio of ORs for ROSC was 0.84 (0.75-0.94), implying that the effect of time to first defibrillation on ROSC was negatively modified by defibrillation waveform. For the interaction between the defibrillation waveform and the number of defibrillations, RERI and ratio of ORs for CPC (1, 2) was -0.25 (-0.47 to -0.06) and 0.79 (0.67-0.93), respectively. It is implied that the effect of number of defibrillation on CPC (1, 2) was negatively modified by defibrillation waveform. An increased number of defibrillations was associated with a decreased ROSC in the case of biphasic and monophasic defibrillation, while an increased number of defibrillations was related to an increased 1-month survival rate and CPC (1, 2) only in the case of

  7. Ensemble Kalman filter regularization using leave-one-out data cross-validation

    KAUST Repository

    Rayo Schiappacasse, Lautaro Jeró nimo; Hoteit, Ibrahim

    2012-01-01

    In this work, the classical leave-one-out cross-validation method for selecting a regularization parameter for the Tikhonov problem is implemented within the EnKF framework. Following the original concept, the regularization parameter is selected

  8. Empirical Performance of Cross-Validation With Oracle Methods in a Genomics Context.

    Science.gov (United States)

    Martinez, Josue G; Carroll, Raymond J; Müller, Samuel; Sampson, Joshua N; Chatterjee, Nilanjan

    2011-11-01

    When employing model selection methods with oracle properties such as the smoothly clipped absolute deviation (SCAD) and the Adaptive Lasso, it is typical to estimate the smoothing parameter by m-fold cross-validation, for example, m = 10. In problems where the true regression function is sparse and the signals large, such cross-validation typically works well. However, in regression modeling of genomic studies involving Single Nucleotide Polymorphisms (SNP), the true regression functions, while thought to be sparse, do not have large signals. We demonstrate empirically that in such problems, the number of selected variables using SCAD and the Adaptive Lasso, with 10-fold cross-validation, is a random variable that has considerable and surprising variation. Similar remarks apply to non-oracle methods such as the Lasso. Our study strongly questions the suitability of performing only a single run of m-fold cross-validation with any oracle method, and not just the SCAD and Adaptive Lasso.

  9. A protocol for patients with cardiovascular implantable devices undergoing magnetic resonance imaging (MRI): should defibrillation threshold testing be performed post-(MRI).

    Science.gov (United States)

    Burke, Peter Thomas; Ghanbari, Hamid; Alexander, Patrick B; Shaw, Michael K; Daccarett, Marcos; Machado, Christian

    2010-06-01

    Magnetic resonance imaging (MRI) in patients with Cardiovascular Implantable Electronic Devices (CIED) has not been approved by the Food and Drug Administration. Recent data suggests MRI as a relative rather than absolute contraindication in CIED patients. Recently, the American Heart Association has recommended defibrillation threshold testing (DFTT) in implantable cardioverter defibrillator (ICD) patients undergoing MRI. We evaluated the feasibility and safety of a protocol for MRI in CIED patients, incorporating the new recommendations on DFTT. Consecutive patients with CIED undergoing MRI were included. The protocol consisted of continuous monitoring during imaging, device interrogation pre- and post-MRI, reprogramming of the pacemaker to an asynchronous mode in pacemaker-dependent (PMD) patients and a non-tracking/sensing mode for non-PMD patients. All tachyarrhythmia therapies were disabled. Devices were interrogated for lead impedance, battery life, pacing, and sensing thresholds. All patients with ICD underwent DFTT/defibrillator safety margin testing (DSMT) post-MRI. A total of 92 MRI's at 1.5 Tesla were performed in 38 patients. A total of 13 PMD patients, ten ICD patients, four cardiac resynchronization therapy with defibrillator (CRT-D) patients, and 11 non-PMD patients were scanned from four major manufacturers. No device circuitry damage, programming alterations, inappropriate shocks, failure to pace, or changes in sensing, pacing, or defibrillator thresholds were found on single or multiple MRI sessions. Our protocol for MRI in CIED patients appears safe, feasible, and reproducible. This is irrespective of the type of CIED, pacemaker dependancy or multiple 24-h scanning sessions. Our protocol addresses early detection of potential complications and establishes a response system for potential device-related complications. Our observation suggests that routine DFTT/DSMT post-MRI may not be necessary.

  10. Non-linear dynamical signal characterization for prediction of defibrillation success through machine learning

    Directory of Open Access Journals (Sweden)

    Shandilya Sharad

    2012-10-01

    Full Text Available Abstract Background Ventricular Fibrillation (VF is a common presenting dysrhythmia in the setting of cardiac arrest whose main treatment is defibrillation through direct current countershock to achieve return of spontaneous circulation. However, often defibrillation is unsuccessful and may even lead to the transition of VF to more nefarious rhythms such as asystole or pulseless electrical activity. Multiple methods have been proposed for predicting defibrillation success based on examination of the VF waveform. To date, however, no analytical technique has been widely accepted. We developed a unique approach of computational VF waveform analysis, with and without addition of the signal of end-tidal carbon dioxide (PetCO2, using advanced machine learning algorithms. We compare these results with those obtained using the Amplitude Spectral Area (AMSA technique. Methods A total of 90 pre-countershock ECG signals were analyzed form an accessible preshosptial cardiac arrest database. A unified predictive model, based on signal processing and machine learning, was developed with time-series and dual-tree complex wavelet transform features. Upon selection of correlated variables, a parametrically optimized support vector machine (SVM model was trained for predicting outcomes on the test sets. Training and testing was performed with nested 10-fold cross validation and 6–10 features for each test fold. Results The integrative model performs real-time, short-term (7.8 second analysis of the Electrocardiogram (ECG. For a total of 90 signals, 34 successful and 56 unsuccessful defibrillations were classified with an average Accuracy and Receiver Operator Characteristic (ROC Area Under the Curve (AUC of 82.2% and 85%, respectively. Incorporation of the end-tidal carbon dioxide signal boosted Accuracy and ROC AUC to 83.3% and 93.8%, respectively, for a smaller dataset containing 48 signals. VF analysis using AMSA resulted in accuracy and ROC AUC of 64

  11. Biased binomial assessment of cross-validated estimation of classification accuracies illustrated in diagnosis predictions

    Directory of Open Access Journals (Sweden)

    Quentin Noirhomme

    2014-01-01

    Full Text Available Multivariate classification is used in neuroimaging studies to infer brain activation or in medical applications to infer diagnosis. Their results are often assessed through either a binomial or a permutation test. Here, we simulated classification results of generated random data to assess the influence of the cross-validation scheme on the significance of results. Distributions built from classification of random data with cross-validation did not follow the binomial distribution. The binomial test is therefore not adapted. On the contrary, the permutation test was unaffected by the cross-validation scheme. The influence of the cross-validation was further illustrated on real-data from a brain–computer interface experiment in patients with disorders of consciousness and from an fMRI study on patients with Parkinson disease. Three out of 16 patients with disorders of consciousness had significant accuracy on binomial testing, but only one showed significant accuracy using permutation testing. In the fMRI experiment, the mental imagery of gait could discriminate significantly between idiopathic Parkinson's disease patients and healthy subjects according to the permutation test but not according to the binomial test. Hence, binomial testing could lead to biased estimation of significance and false positive or negative results. In our view, permutation testing is thus recommended for clinical application of classification with cross-validation.

  12. Biased binomial assessment of cross-validated estimation of classification accuracies illustrated in diagnosis predictions.

    Science.gov (United States)

    Noirhomme, Quentin; Lesenfants, Damien; Gomez, Francisco; Soddu, Andrea; Schrouff, Jessica; Garraux, Gaëtan; Luxen, André; Phillips, Christophe; Laureys, Steven

    2014-01-01

    Multivariate classification is used in neuroimaging studies to infer brain activation or in medical applications to infer diagnosis. Their results are often assessed through either a binomial or a permutation test. Here, we simulated classification results of generated random data to assess the influence of the cross-validation scheme on the significance of results. Distributions built from classification of random data with cross-validation did not follow the binomial distribution. The binomial test is therefore not adapted. On the contrary, the permutation test was unaffected by the cross-validation scheme. The influence of the cross-validation was further illustrated on real-data from a brain-computer interface experiment in patients with disorders of consciousness and from an fMRI study on patients with Parkinson disease. Three out of 16 patients with disorders of consciousness had significant accuracy on binomial testing, but only one showed significant accuracy using permutation testing. In the fMRI experiment, the mental imagery of gait could discriminate significantly between idiopathic Parkinson's disease patients and healthy subjects according to the permutation test but not according to the binomial test. Hence, binomial testing could lead to biased estimation of significance and false positive or negative results. In our view, permutation testing is thus recommended for clinical application of classification with cross-validation.

  13. Canadian Registry of ICD Implant Testing procedures (CREDIT): current practice, risks, and costs of intraoperative defibrillation testing.

    Science.gov (United States)

    Healey, Jeff S; Dorian, Paul; Mitchell, L Brent; Talajic, Mario; Philippon, Francois; Simpson, Chris; Yee, Raymond; Morillo, Carlos A; Lamy, Andre; Basta, Magdy; Birnie, David H; Wang, Xiaoyin; Nair, Girish M; Crystal, Eugene; Kerr, Charles R; Connolly, Stuart J

    2010-02-01

    There is uncertainty about the proper role of defibrillation testing (DT) at the time of implantable cardioverter defibrillator (ICD) insertion. A prospective registry was conducted at 13 sites in Canada between January 2006 and October 2007. To document the details of DT, the reasons for not conducting DT, and the costs and complications associated with DT. DT was conducted at implantation in 230 of 361 patients (64%). DT was more likely to be conducted for new implants compared with impulse generator replacements (71% vs 32%, P = 0.0001), but was similar for primary and secondary prevention indications (64% vs 63%, P = NS). Among patients not having DT, the reason(s) given were: considered unnecessary (44%); considered unsafe, mainly due to persistent atrial fibrillation (37%); lack of an anesthetist (20%); and, patient or physician preference (6%). When performed, DT consisted of a single successful shock > or = 10J below maximum device output in 65% of cases. A 10J safety-margin was met by 97% of patients, requiring system modification in 2.3%. Major perioperative complications occurred in 4.4% of patients having DT versus 6.6% of patients not having DT (P = NS). ICD insertion was $844 more expensive for patients having DT (P = 0.16), largely due to increased costs ($28,017 vs $24,545) among patients having impulse generator replacement (P = 0.02). DT was not performed in a third of ICD implants, usually due to a perceived lack of need or relative contraindication.

  14. Accelerating cross-validation with total variation and its application to super-resolution imaging.

    Directory of Open Access Journals (Sweden)

    Tomoyuki Obuchi

    Full Text Available We develop an approximation formula for the cross-validation error (CVE of a sparse linear regression penalized by ℓ1-norm and total variation terms, which is based on a perturbative expansion utilizing the largeness of both the data dimensionality and the model. The developed formula allows us to reduce the necessary computational cost of the CVE evaluation significantly. The practicality of the formula is tested through application to simulated black-hole image reconstruction on the event-horizon scale with super resolution. The results demonstrate that our approximation reproduces the CVE values obtained via literally conducted cross-validation with reasonably good precision.

  15. Ensemble Kalman filter regularization using leave-one-out data cross-validation

    KAUST Repository

    Rayo Schiappacasse, Lautaro Jerónimo

    2012-09-19

    In this work, the classical leave-one-out cross-validation method for selecting a regularization parameter for the Tikhonov problem is implemented within the EnKF framework. Following the original concept, the regularization parameter is selected such that it minimizes the predictive error. Some ideas about the implementation, suitability and conceptual interest of the method are discussed. Finally, what will be called the data cross-validation regularized EnKF (dCVr-EnKF) is implemented in a 2D 2-phase synthetic oil reservoir experiment and the results analyzed.

  16. Electrical storm presages nonsudden death: the antiarrhythmics versus implantable defibrillators (AVID) trial.

    Science.gov (United States)

    Exner, D V; Pinski, S L; Wyse, D G; Renfroe, E G; Follmann, D; Gold, M; Beckman, K J; Coromilas, J; Lancaster, S; Hallstrom, A P

    2001-04-24

    Electrical storm, multiple temporally related episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF), is a frequent problem among recipients of implantable cardioverter defibrillators (ICDs). However, insufficient data exist regarding its prognostic significance. This analysis includes 457 patients who received an ICD in the Antiarrhythmics Versus Implantable Defibrillators (AVID) trial and who were followed for 31 +/- 13 months. Electrical storm was defined as > or = 3 separate episodes of VT/VF within 24 hours. Characteristics and survival of patients surviving electrical storm (n = 90), those with VT/VF unrelated to electrical storm (n = 184), and the remaining patients (n = 183) were compared. The 3 groups differed in terms of ejection fraction, index arrhythmia, revascularization status, and baseline medication use. Survival was evaluated using time-dependent Cox modeling. Electrical storm occurred 9.2 +/- 11.5 months after ICD implantation, and most episodes (86%) were due to VT. Electrical storm was a significant risk factor for subsequent death, independent of ejection fraction and other prognostic variables (relative risk [RR], 2.4; 95% confidence interval [CI], 1.3 to 4.2; P = 0.003), but VT/VF unrelated to electrical storm was not (RR, 1.0; 95% CI, 0.6 to 1.7; P = 0.9). The risk of death was greatest 3 months after electrical storm (RR, 5.4; 95% Cl, 2.4 to 12.3; P = 0.0001) and diminished beyond this time (RR, 1.9; 95% CI, 1.0 to 3.6; P=0.04). Electrical storm is an important, independent marker for subsequent death among ICD recipients, particularly in the first 3 months after its occurrence. However, the development of VT/VF unrelated to electrical storm does not seem to be associated with an increased risk of subsequent death.

  17. Physicians’ knowledge and attitudes in Saudi Arabia regarding implantable cardiac defibrillators

    Directory of Open Access Journals (Sweden)

    Tariq Alhogbani

    2018-04-01

    Full Text Available Objectives: To evaluate knowledge and attitude of physicians involved in the management of patients with heart failure regarding implantable cardioverter-defibrillator (ICD. Methods: We conducted personal interviews with physicians involved in treating patients with heart failure. Between October 2015 and February 2016, the study was conducted in hospitals in the Riyadh region where no cardiac electrophysiology service was available. Every participant was met in person and received an oral questionnaire that aimed to assess basic knowledge regarding ICD indications and benefits. Results: Sixty-three physicians were met from 13 hospitals (14 consultants and 49 specialists. Forty-one percent of participants use the recommended cut-off level of left ventricular ejection fraction (LVEF which is ≤35% as the LVEF criterion for ICD referral in patients with cardiomyopathy. Only 50% of the consultants use ≤35% as the LVEF criterion for ICD referral. Seventy percent of the participants thought that ICD may improve heart failure symptoms. Forty-eight percent of physicians have a defined channel to refer patients to higher centers for ICD implant. There was no statistically significant difference between physicians’ knowledge when we categorized them according to three different factors: (1 physician’s specialty (cardiology vs. internal medicine; (2 physician’s degree (consultant vs. specialist; and (3 physician’s location (inside vs. outside Riyadh city. Conclusion: There is a lack of knowledge of current clinical guidelines regarding ICD implantation for patients with heart failure at general hospitals in Saudi Arabia. This finding highlights the need to improve the dissemination of guidelines to practitioners involved in managing patients with heart failure in an effort to improve ICD utilization. Keywords: Cardiac defibrillator, Heart failure, Physicians’ knowledge, Saudi Arabia

  18. A Cross-Validation Study of Police Recruit Performance as Predicted by the IPI and MMPI.

    Science.gov (United States)

    Shusman, Elizabeth J.; And Others

    Validation and cross-validation studies were conducted using the Minnesota Multiphasic Personality Inventory (MMPI) and Inwald Personality Inventory (IPI) to predict job performance for 698 urban male police officers who completed a six-month training academy. Job performance criteria evaluated included absence, lateness, derelictions, negative…

  19. Efficient approximate k-fold and leave-one-out cross-validation for ridge regression

    NARCIS (Netherlands)

    Meijer, R.J.; Goeman, J.J.

    2013-01-01

    In model building and model evaluation, cross-validation is a frequently used resampling method. Unfortunately, this method can be quite time consuming. In this article, we discuss an approximation method that is much faster and can be used in generalized linear models and Cox' proportional hazards

  20. [Public access defibrillation: successful cardiopulmonary resuscitation due to automatic external defibrillator at traffic accident].

    Science.gov (United States)

    Wanke, S; Reuter, H; Pfister, R; Michels, G

    2014-03-01

    A 65-year-old man collapsed after he stepped out of his car after a traffic accident. Fortunately, two police officers on a routine patrol in the area were quickly on the scene and started cardiopulmonary resuscitation. A passerby noticed that the patient was in distress and that an automatic defibrillator was nearby. He attached the electrodes of the defibrillator to the chest of the patient in accordance with instructions on the defibrillator and terminated the ventricular fibrillation (200 joule, biphasic). Emergency cardiac catheterization revealed a subtotal stenosis proximally in the right coronary artery, which was successfully treated with a stent. Based on the ideal basic life support, the immediate care by emergency mobile system and coronary angioplasty with successful revascularisation the patient could be released without any neurological deficit. This case illustrates that laypersons can use automatic external defibrillator in case of cardiac resuscitation sufficiently and quickly. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Externalized conductors and insulation failure in Biotronik defibrillator leads: History repeating or a false alarm?

    Science.gov (United States)

    De Maria, Elia; Borghi, Ambra; Bonetti, Lorenzo; Fontana, Pier Luigi; Cappelli, Stefano

    2017-02-16

    Conductor externalization and insulation failure are frequent complications with the recalled St. Jude Medical Riata implantable cardioverter-defibrillator (ICD) leads. Conductor externalization is a "unique" failure mechanism: Cables externalize through the insulation ("inside-out" abrasion) and appear outside the lead body. Recently, single reports described a similar failure also for Biotronik leads. Moreover, some studies reported a high rate of electrical dysfunction (not only insulation failure) with Biotronik Linox leads and a reduced survival rate in comparison with the competitors. In this paper we describe the case of a patient with a Biotronik Kentrox ICD lead presenting with signs of insulation failure and conductor externalization at fluoroscopy. Due to the high risk of extraction we decided to implant a new lead, abandoning the damaged one; lead reimplant was uneventful. Subsequently, we review currently available literature about Biotronik Kentrox and Linox ICD lead failure and in particular externalized conductors. Some single-center studies and a non-prospective registry reported a survival rate between 88% and 91% at 5 years for Linox leads, significantly worse than that of other manufacturers. However, the preliminary results of two ongoing multicenter, prospective registries (GALAXY and CELESTIAL) showed 96% survival rate at 5 years after implant, well within industry standards. Ongoing data collection is needed to confirm longer-term performance of this family of ICD leads.

  2. Electrical storm in patients with an implanted defibrillator: a matter of definition.

    Science.gov (United States)

    Israel, Carsten W; Barold, S Serge

    2007-10-01

    The term "electrical storm" (ES) indicates a state of cardiac electrical instability manifested by several episodes of ventricular tachyarrhythmias (VTs) within a short time. In patients with an implantable cardioverter defibrillator (ICD), ES is best defined as 3 appropriate VT detections in 24 h, treated by antitachycardia pacing, shock or eventually untreated but sustained in a VT monitoring zone. The number of shocks and inappropriate detections are irrelevant for the definition. ES occurs in approximately 25% of ICD patients within 3 years, with typically 5-55 individual VTs within one storm. Potential triggers can be found in approximately 66% of patients and include new/worsened heart failure, changes in antiarrhythmic medication, context with other illness, psychological stress, diarrhea, and hypokalemia. In most patients, ES consists of monomorphic VT indicating the presence of reentry while ventricular fibrillation indicating acute ischemia is rare. ES seems to have a low immediate mortality (1%) but frequently (50-80%) leads to hospitalization. Long-term prognostic implications of ES are unclear. The key intervention in ES is reduction of the elevated sympathetic tone by beta blockers and frequently benzodiazepines. Amiodarone i.v. has also been successful and azimilide seems promising while class I antiarrhythmic drugs are usually unsuccessful. Substrate mapping and VT ablation may be useful in treatment and prevention of ES. Prevention of ES requires ICD programming systematically avoiding unnecessary shocks (long VT detection, antitachycardia pacing where ever possible) which otherwise can fuel the sympathetic tone and prolong ES.

  3. Validation of defibrillator lead performance registry data

    DEFF Research Database (Denmark)

    Kristensen, Anders Elgaard; Larsen, Jacob Moesgaard; Nielsen, Jens Cosedis

    2017-01-01

    all reported surgical interventions due to defibrillator lead events in the Danish Pacemaker and ICD Register (DPIR) from 2000 to 2013. Medical records of all patients (n = 753) were examined blinded for 5 predefined intervention types and 18 reasons for lead intervention. The overall level...

  4. On the use of the observation-wise k-fold operation in PCA cross-validation

    NARCIS (Netherlands)

    Saccenti, E.; Camacho, J.

    2015-01-01

    Cross-validation (CV) is a common approach for determining the optimal number of components in a principal component analysis model. To guarantee the independence between model testing and calibration, the observationwise k-fold operation is commonly implemented in each cross-validation step. This

  5. Association between implantable cardioverter-defibrillator therapy and different lead positions in patients with cardiac resynchronization therapy

    DEFF Research Database (Denmark)

    Kronborg, Mads Brix; Johansen, Jens Brock; Haarbo, Jens

    2017-01-01

    /mid-ventricular/apical for the LV-LP, and as apical/non-apical for the RV-LP. Appropriate and inappropriate therapies were registered during follow-up via remote monitoring or at device interrogations. Time to event was summarized with Kaplan-Meier plots, and competed risk regression analysis was used to calculate adjusted hazard...... with an apical. We observed no significant association between appropriate therapy and LV-LP in left anterior oblique or right anterior oblique views or inappropriate therapy between any lead positions. Conclusion: An apical RV-LP is associated with an increased risk of appropriate therapy for ventricular...

  6. Self-reported quality of life predicts mortality 7 years post implant in patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Andersen, Christina Maar; Veen, Barbara van; Theuns, Dominic A M J

    2018-01-01

    (SD) age=58 (12) consecutively implanted between 2003 and 2010. Patients completed the SF-36. The eight subscales and the physical and mental component summary scores were used as predictors of mortality 7 years post implant. Results: At 7-year follow-up, 33.7% (132/392) of the patients had died...

  7. Relation of symptomatic heart failure and psychological status to persistent depression in patients with implantable cardioverter-defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; Hoogwegt, Madelein T; Jordaens, Luc

    2011-01-01

    . We examined the prevalence and correlates of persistent depression using an intraindividual approach. Consecutive patients who had undergone ICD implantation (n = 386; 79.3% men) completed a set of validated questionnaires, including the Hospital Anxiety and Depression Scale (HADS), at baseline and 3...... months after implantation. Information on ICD therapies was obtained by device interrogation. At 3 months after implantation, 52 (14%) of the 386 patients had persistent depression (HADS cutoff ≥8 before and 3 months after implantation). Heart failure (odds ratio [OR] 2.29; 95% confidence interval [CI] 1.......71), diuretics (OR 2.41; 95% CI 1.26 to 4.61), and psychotropic medication (OR 3.58; 95% CI 1.86 to 6.90) were all significant univariate correlates of persistent depression at 3 months. No effect was found for ICD shock during follow-up (OR 1.59; 95% CI 0.57 to 4.41). In adjusted analysis, New York Heart...

  8. The impact of co-morbidity burden on appropriate implantable cardioverter defibrillator therapy and all-cause mortality

    DEFF Research Database (Denmark)

    Ruwald, Anne Christine; Vinther, Michael; Gislason, Gunnar H

    2017-01-01

    -ICD indication-related co-morbidities including atrial fibrillation, diabetes, chronic obstructive pulmonary disease, chronic renal disease, liver disease, cancer, chronic psychiatric disease, and peripheral and/or cerebrovascular disease, and divided into four groups (co-morbidity burden 0, 1, 2, and ≥3......). Through Cox models, we assessed the impact of co-morbidity burden on appropriate ICD therapy and mortality. Increasing co-morbidity burden was not associated with increased risk of appropriate therapy, irrespective of implant indication [all hazard ratios (HRs) 1.0-1.4, P = NS]. Using no co...

  9. The Screen-ICD trial. Screening for anxiety and cognitive therapy intervention for patients with implanted cardioverter defibrillator (ICD)

    DEFF Research Database (Denmark)

    Berg, Selina Kikkenborg; Herning, Margrethe; Svendsen, Jesper Hastrup

    2016-01-01

    by Structured Clinical Interview for DSM Disorders (SCID). (3) Investigator-initiated randomised clinical superiority trial with blinded outcome assessment, with 1:1 randomisation to cognitive–behavioural therapy (CBT) performed by a cardiac nurse with CBT training, plus usual care or usual care alone...... of starting relevant intervention. Methods and analysis: Screen-ICD consists of 3 parts: (1) screening of all hospitalised and outpatient patients at two university hospitals using the Hospital Anxiety and Depression Scale (HADS), scores ≥8 are invited to participate. (2) Assessment of type of anxiety...

  10. Classification in hyperspectral images by independent component analysis, segmented cross-validation and uncertainty estimates

    Directory of Open Access Journals (Sweden)

    Beatriz Galindo-Prieto

    2018-02-01

    Full Text Available Independent component analysis combined with various strategies for cross-validation, uncertainty estimates by jack-knifing and critical Hotelling’s T2 limits estimation, proposed in this paper, is used for classification purposes in hyperspectral images. To the best of our knowledge, the combined approach of methods used in this paper has not been previously applied to hyperspectral imaging analysis for interpretation and classification in the literature. The data analysis performed here aims to distinguish between four different types of plastics, some of them containing brominated flame retardants, from their near infrared hyperspectral images. The results showed that the method approach used here can be successfully used for unsupervised classification. A comparison of validation approaches, especially leave-one-out cross-validation and regions of interest scheme validation is also evaluated.

  11. Cross-Validation of Survival Bump Hunting by Recursive Peeling Methods.

    Science.gov (United States)

    Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J Sunil

    2014-08-01

    We introduce a survival/risk bump hunting framework to build a bump hunting model with a possibly censored time-to-event type of response and to validate model estimates. First, we describe the use of adequate survival peeling criteria to build a survival/risk bump hunting model based on recursive peeling methods. Our method called "Patient Recursive Survival Peeling" is a rule-induction method that makes use of specific peeling criteria such as hazard ratio or log-rank statistics. Second, to validate our model estimates and improve survival prediction accuracy, we describe a resampling-based validation technique specifically designed for the joint task of decision rule making by recursive peeling (i.e. decision-box) and survival estimation. This alternative technique, called "combined" cross-validation is done by combining test samples over the cross-validation loops, a design allowing for bump hunting by recursive peeling in a survival setting. We provide empirical results showing the importance of cross-validation and replication.

  12. Will medical examination gloves protect rescuers from defibrillation voltages during hands-on defibrillation?

    Science.gov (United States)

    Sullivan, Joseph L; Chapman, Fred W

    2012-12-01

    Continuing compressions during a defibrillation shock has been proposed as a method of reducing pauses in cardiopulmonary resuscitation (CPR) but the safety of this procedure is unproven. The medical examination gloves worn by rescuers play an important role in protecting the rescuer yet the electrical characteristics of these gloves are unknown. This study examined the response of medical examination gloves to defibrillation voltages. Part 1 of this study measured voltage-current curves for a small sample (8) of gloves. Part 2 tested more gloves (460) to determine the voltage required to produce a specific amount of current flow. Gloves were tested at two current levels: 0.1 mA and 10 mA. Testing included four glove materials (chloroprene, latex, nitrile, and vinyl) in a single layer and double-gloved. All gloves tested in part 1 allowed little current to flow (gloves and 93 of 120 (77%) double gloves allowed at least 0.1 mA of current flow at voltages within the external defibrillation voltage range. Also, 6 of 80 (7.5%) single gloves and 5 of 80 (6.2%) double gloves allowed over 10 mA. Few of the gloves tested limited the current to levels proven to be safe. A lack of sensation during hands-on defibrillation does not guarantee that a safety margin exists. As such, we encourage rescuers to minimize rather than eliminate the pause in compressions for defibrillation. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  13. Fast Electrocardiogram Amplifier Recovery after Defibrillation Shock

    Directory of Open Access Journals (Sweden)

    Ivan Dotsinsky

    2005-04-01

    Full Text Available A procedure for fast ECG amplifier recovery after defibrillation shocks was developed and simulated in the MATLAB environment. Exponentially decaying post-shock voltages have been recorded. Signals from the AHA database are taken and mixed with the recorded exponential disturbances. The algorithm applies moving averaging (comb filter on the compound input signal, thereby obtaining the samples of the disturbance. They are currently subtracted from the input signal. The results obtained show that its recovery is practically instantaneous.

  14. Raman fiber-optical method for colon cancer detection: Cross-validation and outlier identification approach

    Science.gov (United States)

    Petersen, D.; Naveed, P.; Ragheb, A.; Niedieker, D.; El-Mashtoly, S. F.; Brechmann, T.; Kötting, C.; Schmiegel, W. H.; Freier, E.; Pox, C.; Gerwert, K.

    2017-06-01

    Endoscopy plays a major role in early recognition of cancer which is not externally accessible and therewith in increasing the survival rate. Raman spectroscopic fiber-optical approaches can help to decrease the impact on the patient, increase objectivity in tissue characterization, reduce expenses and provide a significant time advantage in endoscopy. In gastroenterology an early recognition of malign and precursor lesions is relevant. Instantaneous and precise differentiation between adenomas as precursor lesions for cancer and hyperplastic polyps on the one hand and between high and low-risk alterations on the other hand is important. Raman fiber-optical measurements of colon biopsy samples taken during colonoscopy were carried out during a clinical study, and samples of adenocarcinoma (22), tubular adenomas (141), hyperplastic polyps (79) and normal tissue (101) from 151 patients were analyzed. This allows us to focus on the bioinformatic analysis and to set stage for Raman endoscopic measurements. Since spectral differences between normal and cancerous biopsy samples are small, special care has to be taken in data analysis. Using a leave-one-patient-out cross-validation scheme, three different outlier identification methods were investigated to decrease the influence of systematic errors, like a residual risk in misplacement of the sample and spectral dilution of marker bands (esp. cancerous tissue) and therewith optimize the experimental design. Furthermore other validations methods like leave-one-sample-out and leave-one-spectrum-out cross-validation schemes were compared with leave-one-patient-out cross-validation. High-risk lesions were differentiated from low-risk lesions with a sensitivity of 79%, specificity of 74% and an accuracy of 77%, cancer and normal tissue with a sensitivity of 79%, specificity of 83% and an accuracy of 81%. Additionally applied outlier identification enabled us to improve the recognition of neoplastic biopsy samples.

  15. Raman fiber-optical method for colon cancer detection: Cross-validation and outlier identification approach.

    Science.gov (United States)

    Petersen, D; Naveed, P; Ragheb, A; Niedieker, D; El-Mashtoly, S F; Brechmann, T; Kötting, C; Schmiegel, W H; Freier, E; Pox, C; Gerwert, K

    2017-06-15

    Endoscopy plays a major role in early recognition of cancer which is not externally accessible and therewith in increasing the survival rate. Raman spectroscopic fiber-optical approaches can help to decrease the impact on the patient, increase objectivity in tissue characterization, reduce expenses and provide a significant time advantage in endoscopy. In gastroenterology an early recognition of malign and precursor lesions is relevant. Instantaneous and precise differentiation between adenomas as precursor lesions for cancer and hyperplastic polyps on the one hand and between high and low-risk alterations on the other hand is important. Raman fiber-optical measurements of colon biopsy samples taken during colonoscopy were carried out during a clinical study, and samples of adenocarcinoma (22), tubular adenomas (141), hyperplastic polyps (79) and normal tissue (101) from 151 patients were analyzed. This allows us to focus on the bioinformatic analysis and to set stage for Raman endoscopic measurements. Since spectral differences between normal and cancerous biopsy samples are small, special care has to be taken in data analysis. Using a leave-one-patient-out cross-validation scheme, three different outlier identification methods were investigated to decrease the influence of systematic errors, like a residual risk in misplacement of the sample and spectral dilution of marker bands (esp. cancerous tissue) and therewith optimize the experimental design. Furthermore other validations methods like leave-one-sample-out and leave-one-spectrum-out cross-validation schemes were compared with leave-one-patient-out cross-validation. High-risk lesions were differentiated from low-risk lesions with a sensitivity of 79%, specificity of 74% and an accuracy of 77%, cancer and normal tissue with a sensitivity of 79%, specificity of 83% and an accuracy of 81%. Additionally applied outlier identification enabled us to improve the recognition of neoplastic biopsy samples. Copyright

  16. Superior Rhythm Discrimination With the SmartShock Technology Algorithm - Results of the Implantable Defibrillator With Enhanced Features and Settings for Reduction of Inaccurate Detection (DEFENSE) Trial.

    Science.gov (United States)

    Oginosawa, Yasushi; Kohno, Ritsuko; Honda, Toshihiro; Kikuchi, Kan; Nozoe, Masatsugu; Uchida, Takayuki; Minamiguchi, Hitoshi; Sonoda, Koichiro; Ogawa, Masahiro; Ideguchi, Takeshi; Kizaki, Yoshihisa; Nakamura, Toshihiro; Oba, Kageyuki; Higa, Satoshi; Yoshida, Keiki; Tsunoda, Soichi; Fujino, Yoshihisa; Abe, Haruhiko

    2017-08-25

    Shocks delivered by implanted anti-tachyarrhythmia devices, even when appropriate, lower the quality of life and survival. The new SmartShock Technology ® (SST) discrimination algorithm was developed to prevent the delivery of inappropriate shock. This prospective, multicenter, observational study compared the rate of inaccurate detection of ventricular tachyarrhythmia using the SST vs. a conventional discrimination algorithm.Methods and Results:Recipients of implantable cardioverter defibrillators (ICD) or cardiac resynchronization therapy defibrillators (CRT-D) equipped with the SST algorithm were enrolled and followed up every 6 months. The tachycardia detection rate was set at ≥150 beats/min with the SST algorithm. The primary endpoint was the time to first inaccurate detection of ventricular tachycardia (VT) with conventional vs. the SST discrimination algorithm, up to 2 years of follow-up. Between March 2012 and September 2013, 185 patients (mean age, 64.0±14.9 years; men, 74%; secondary prevention indication, 49.5%) were enrolled at 14 Japanese medical centers. Inaccurate detection was observed in 32 patients (17.6%) with the conventional, vs. in 19 patients (10.4%) with the SST algorithm. SST significantly lowered the rate of inaccurate detection by dual chamber devices (HR, 0.50; 95% CI: 0.263-0.950; P=0.034). Compared with previous algorithms, the SST discrimination algorithm significantly lowered the rate of inaccurate detection of VT in recipients of dual-chamber ICD or CRT-D.

  17. A statistical method (cross-validation) for bone loss region detection after spaceflight

    Science.gov (United States)

    Zhao, Qian; Li, Wenjun; Li, Caixia; Chu, Philip W.; Kornak, John; Lang, Thomas F.

    2010-01-01

    Astronauts experience bone loss after the long spaceflight missions. Identifying specific regions that undergo the greatest losses (e.g. the proximal femur) could reveal information about the processes of bone loss in disuse and disease. Methods for detecting such regions, however, remains an open problem. This paper focuses on statistical methods to detect such regions. We perform statistical parametric mapping to get t-maps of changes in images, and propose a new cross-validation method to select an optimum suprathreshold for forming clusters of pixels. Once these candidate clusters are formed, we use permutation testing of longitudinal labels to derive significant changes. PMID:20632144

  18. The development and cross-validation of an MMPI typology of murderers.

    Science.gov (United States)

    Holcomb, W R; Adams, N A; Ponder, H M

    1985-06-01

    A sample of 80 male offenders charged with premeditated murder were divided into five personality types using MMPI scores. A hierarchical clustering procedure was used with a subsequent internal cross-validation analysis using a second sample of 80 premeditated murderers. A Discriminant Analysis resulted in a 96.25% correct classification of subjects from the second sample into the five types. Clinical data from a mental status interview schedule supported the external validity of these types. There were significant differences among the five types in hallucinations, disorientation, hostility, depression, and paranoid thinking. Both similarities and differences of the present typology with prior research was discussed. Additional research questions were suggested.

  19. Cross-validation of an employee safety climate model in Malaysia.

    Science.gov (United States)

    Bahari, Siti Fatimah; Clarke, Sharon

    2013-06-01

    Whilst substantial research has investigated the nature of safety climate, and its importance as a leading indicator of organisational safety, much of this research has been conducted with Western industrial samples. The current study focuses on the cross-validation of a safety climate model in the non-Western industrial context of Malaysian manufacturing. The first-order factorial validity of Cheyne et al.'s (1998) [Cheyne, A., Cox, S., Oliver, A., Tomas, J.M., 1998. Modelling safety climate in the prediction of levels of safety activity. Work and Stress, 12(3), 255-271] model was tested, using confirmatory factor analysis, in a Malaysian sample. Results showed that the model fit indices were below accepted levels, indicating that the original Cheyne et al. (1998) safety climate model was not supported. An alternative three-factor model was developed using exploratory factor analysis. Although these findings are not consistent with previously reported cross-validation studies, we argue that previous studies have focused on validation across Western samples, and that the current study demonstrates the need to take account of cultural factors in the development of safety climate models intended for use in non-Western contexts. The results have important implications for the transferability of existing safety climate models across cultures (for example, in global organisations) and highlight the need for future research to examine cross-cultural issues in relation to safety climate. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.

  20. Analysis of implantable defibrillator longevity under clinical circumstances: implications for device selection.

    Science.gov (United States)

    Knops, Paul; Theuns, Dominic A M J; Res, Jan C J; Jordaens, Luc

    2009-10-01

    Information about implantable cardioverter-defibrillator (ICD) longevity is mostly calculated from measurements under ideal laboratory conditions. However, little information about longevity under clinical circumstances is available. This survey gives an overview on ICD service times and generator replacements in a cohort of consecutive ICD patients. Indications for replacement were classified as a normal end-of-service (EOS), premature EOS, system malfunction, infection and device advisory, or recall actions. From the premature and normal EOS group, longevity from single-chamber (SC), dual-chamber (DC), and cardiac resynchronization therapy defibrillator (CRT-D), rate-responsive (RR) settings, high output (HO) stimulation, and indication for ICD therapy was compared. Differences between brands were compared as well. In a total of 854 patients, 203 ICD replacements (165 patients) were recorded. Premature and normal EOS replacements consisted of 32 SC, 98 DC and 24 CRT-D systems. Longevity was significantly longer in SC systems compared to DC and CRT-D systems (54 +/- 19 vs. 40 +/- 17 and 42 +/- 15 months; P = 0.008). Longevity between non-RR (n = 143) and RR (n = 11) settings was not significantly different (43 +/- 18 vs. 45 +/- 13 months) as it also was not for HO versus non-HO stimulation (43 +/- 19 vs. 46 +/- 17 months). Longevity of ICDs was not significantly different between primary and secondary prevention (42 +/- 19 vs. 44 +/- 18 months). The average longevity on account of a device-based EOS message was 43 +/- 18 months. Average longevity for Biotronik (BIO, n = 72) was 33 +/- 10 months, for ELA Medical (ELA, n = 12) 44 +/- 17 months, for Guidant (GDT, n = 36) 49 +/- 12 months, for Medtronic (MDT, n = 29) 62 +/- 22 months, and for St. Jude Medical (SJM, n = 5) 31 +/- 9 months (P generators had a longer service time compared to DC and CRT-D systems. No influence of indication for ICD therapy and HO stimulation on generator longevity was observed in this

  1. Safety and interaction of patients with implantable cardiac defibrillators driving a hybrid vehicle.

    Science.gov (United States)

    Tondato, Fernando; Bazzell, Jane; Schwartz, Linda; Mc Donald, Bruce W; Fisher, Robert; Anderson, S Shawn; Galindo, Arcenio; Dueck, Amylou C; Scott, Luis R

    2017-01-15

    Electromagnetic interference (EMI) can affect the function of implantable cardioverter defibrillators (ICD). Hybrid electric vehicles (HEV) have increased popularity and are a potential source of EMI. Little is known about the in vivo effects of EMI generated by HEV on ICD. This study evaluated the in vivo interaction between EMI generated by HEV with ICD. Thirty patients (73±9 y/o; 80% male) with stable ICD function were exposed to EMI generated by a Toyota Prius Hybrid®. The vehicle was lifted above the ground, allowing safe changes in engine rotation and consequent variations in electromagnetic emission. EMI was measured (NARDA STS® model EHP-50C) and expressed in A/m (magnetic), Volts/m (electrical), and Hertz (frequency). Six positions were evaluated: driver, front passenger, right and left back seats, outside, at the back and front of the car. Each position was evaluated at idle, 30 mph, 60 mph and variable speeds (acceleration-deceleration-brake). All ICD devices were continuously monitored during the study. The levels of EMI generated were low (highest mean levels: 2.09A/m at right back seat at 30 mph; and 3.5V/m at driver seat at variable speeds). No episode of oversensing or inadvertent change in ICD programming was observed. It is safe for patients with ICD to interact with HEV. This is the first study to address this issue using an in vivo model. Further studies are necessary to evaluate the interaction of different models of HEV or electric engine with ICD or unipolar pacemakers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Assessing the Risks Associated with MRI in Patients with a Pacemaker or Defibrillator.

    Science.gov (United States)

    Russo, Robert J; Costa, Heather S; Silva, Patricia D; Anderson, Jeffrey L; Arshad, Aysha; Biederman, Robert W W; Boyle, Noel G; Frabizzio, Jennifer V; Birgersdotter-Green, Ulrika; Higgins, Steven L; Lampert, Rachel; Machado, Christian E; Martin, Edward T; Rivard, Andrew L; Rubenstein, Jason C; Schaerf, Raymond H M; Schwartz, Jennifer D; Shah, Dipan J; Tomassoni, Gery F; Tominaga, Gail T; Tonkin, Allison E; Uretsky, Seth; Wolff, Steven D

    2017-02-23

    The presence of a cardiovascular implantable electronic device has long been a contraindication for the performance of magnetic resonance imaging (MRI). We established a prospective registry to determine the risks associated with MRI at a magnetic field strength of 1.5 tesla for patients who had a pacemaker or implantable cardioverter-defibrillator (ICD) that was "non-MRI-conditional" (i.e., not approved by the Food and Drug Administration for MRI scanning). Patients in the registry were referred for clinically indicated nonthoracic MRI at a field strength of 1.5 tesla. Devices were interrogated before and after MRI with the use of a standardized protocol and were appropriately reprogrammed before the scanning. The primary end points were death, generator or lead failure, induced arrhythmia, loss of capture, or electrical reset during the scanning. The secondary end points were changes in device settings. MRI was performed in 1000 cases in which patients had a pacemaker and in 500 cases in which patients had an ICD. No deaths, lead failures, losses of capture, or ventricular arrhythmias occurred during MRI. One ICD generator could not be interrogated after MRI and required immediate replacement; the device had not been appropriately programmed per protocol before the MRI. We observed six cases of self-terminating atrial fibrillation or flutter and six cases of partial electrical reset. Changes in lead impedance, pacing threshold, battery voltage, and P-wave and R-wave amplitude exceeded prespecified thresholds in a small number of cases. Repeat MRI was not associated with an increase in adverse events. In this study, device or lead failure did not occur in any patient with a non-MRI-conditional pacemaker or ICD who underwent clinically indicated nonthoracic MRI at 1.5 tesla, was appropriately screened, and had the device reprogrammed in accordance with the prespecified protocol. (Funded by St. Jude Medical and others; MagnaSafe ClinicalTrials.gov number, NCT

  3. Long-term single-center experience of defibrillator therapy in children and adolescents.

    Science.gov (United States)

    Frommeyer, Gerrit; Feder, Sebastian; Bettin, Markus; Debus, Volker; Köbe, Julia; Reinke, Florian; Uebing, Anselm; Eckardt, Lars; Kehl, Hans Gerd

    2018-06-01

    Implantable cardioverter-defibrillator (ICD) systems are established therapy for prevention of sudden cardiac death. Long-term data on ICD systems in children and adolescents is rare. The present study displays a long-term single-center follow-up of children and adolescents with ICD systems. The present study represents a single-center experience of patients younger than 18 years who received an ICD (n = 58). Follow-up data included in-house follow-up as well as examinations of collaborating specialists. Mean age at implantation was 14.0 ± 3.3 years and 33 patients (56.9%) were male. A transvenous ICD system was implanted in 54 patients (93.1%). In 33 patients (56.9%) electrical heart disease or idiopathic ventricular fibrillation represented the underlying condition of ICD implantation. Median follow-up duration was 70 months (45; 94). 3 patients (5.2%) died during the observation period. None of these deaths was associated with ICD failure. Appropriate shocks occurred in 32 patients (55.2%). Inappropriate shock delivery was recorded in 17 patients (29.3%). Supraventricular tachycardia represented the most frequent cause of inappropriate shock delivery (9 patients, 52.9%). T-wave oversensing led to inappropriate shock delivery in 3 patients (17.6%). In 5 patients (29.4%), lead failure caused inappropriate shock delivery. Of note, during follow-up lead failure was reported in 15 patients (25.9%) leading to surgical revision. ICD therapy in children and adolescents is effective for prevention of sudden cardiac death. The rate of appropriate shock deliveries was significantly higher as compared with large ICD trials. Inappropriate therapies occurred frequently. In particular supraventricular tachycardia, T-wave oversensing and lead failures were responsible for these episodes. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. The challenges and possibilities of public access defibrillation.

    Science.gov (United States)

    Ringh, M; Hollenberg, J; Palsgaard-Moeller, T; Svensson, L; Rosenqvist, M; Lippert, F K; Wissenberg, M; Malta Hansen, C; Claesson, A; Viereck, S; Zijlstra, J A; Koster, R W; Herlitz, J; Blom, M T; Kramer-Johansen, J; Tan, H L; Beesems, S G; Hulleman, M; Olasveengen, T M; Folke, F

    2018-03-01

    Out-of-hospital cardiac arrest (OHCA) is a major health problem that affects approximately four hundred and thousand patients annually in the United States alone. It is a major challenge for the emergency medical system as decreased survival rates are directly proportional to the time delay from collapse to defibrillation. Historically, defibrillation has only been performed by physicians and in-hospital. With the development of automated external defibrillators (AEDs), rapid defibrillation by nonmedical professionals and subsequently by trained or untrained lay bystanders has become possible. Much hope has been put to the concept of Public Access Defibrillation with a massive dissemination of public available AEDs throughout most Western countries. Accordingly, current guidelines recommend that AEDs should be deployed in places with a high likelihood of OHCA. Despite these efforts, AED use is in most settings anecdotal with little effect on overall OHCA survival. The major reasons for low use of public AEDs are that most OHCAs take place outside high incidence sites of cardiac arrest and that most OHCAs take place in residential settings, currently defined as not suitable for Public Access Defibrillation. However, the use of new technology for identification and recruitment of lay bystanders and nearby AEDs to the scene of the cardiac arrest as well as new methods for strategic AED placement redefines and challenges the current concept and definitions of Public Access Defibrillation. Existing evidence of Public Access Defibrillation and knowledge gaps and future directions to improve outcomes for OHCA are discussed. In addition, a new definition of the different levels of Public Access Defibrillation is offered as well as new strategies for increasing AED use in the society. © 2018 The Association for the Publication of the Journal of Internal Medicine.

  5. Electrical storm is an independent predictor of adverse long-term outcome in the era of implantable defibrillator therapy.

    Science.gov (United States)

    Gatzoulis, Konstantinos A; Andrikopoulos, George K; Apostolopoulos, Theodoros; Sotiropoulos, Elias; Zervopoulos, George; Antoniou, John; Brili, Stella; Stefanadis, Christodoulos I

    2005-03-01

    Electrical storm (ES) is a life-threatening arrhythmia complication affecting patients treated with an implantable cardioverter defibrillator (ICD). Despite its increasing importance, existing data on prognosis and management of ICD patients affected by ES are limited and conflicting. We prospectively studied 169 consecutive patients receiving an ICD. Thirty-two patients presented with at least one episode of ES during the period of observation (33+/-26 months). ES patients were older (64+/-9 vs. 59+/-13 years, P=0.013) with more advanced congestive heart failure (CHF) but a similar incidence of an underlying organic heart disease. Long-term total and cardiac mortality were both increased among ES patients. Seventeen of the 32 ES patients died as opposed to 19 of the 137 ICD patients without ES (53 vs. 14%, P<0.001). In multivariate Cox regression analysis adjusted for the main confounders, history of ES was significantly and independently associated with total and cardiac mortality (risk ratio (RR)=2.13, P=0.031 and RR=2.59, P=0.019, respectively). ES is a relatively frequent complication affecting ICD patients treated for secondary prevention of sudden cardiac death (SCD). Although the acute management of this serious arrhythmia complication is usually successful, occurrence of ES is a strong independent predictor of poor outcome in ICD patients.

  6. Asymptotic optimality and efficient computation of the leave-subject-out cross-validation

    KAUST Repository

    Xu, Ganggang

    2012-12-01

    Although the leave-subject-out cross-validation (CV) has been widely used in practice for tuning parameter selection for various nonparametric and semiparametric models of longitudinal data, its theoretical property is unknown and solving the associated optimization problem is computationally expensive, especially when there are multiple tuning parameters. In this paper, by focusing on the penalized spline method, we show that the leave-subject-out CV is optimal in the sense that it is asymptotically equivalent to the empirical squared error loss function minimization. An efficient Newton-type algorithm is developed to compute the penalty parameters that optimize the CV criterion. Simulated and real data are used to demonstrate the effectiveness of the leave-subject-out CV in selecting both the penalty parameters and the working correlation matrix. © 2012 Institute of Mathematical Statistics.

  7. Efficient generalized cross-validation with applications to parametric image restoration and resolution enhancement.

    Science.gov (United States)

    Nguyen, N; Milanfar, P; Golub, G

    2001-01-01

    In many image restoration/resolution enhancement applications, the blurring process, i.e., point spread function (PSF) of the imaging system, is not known or is known only to within a set of parameters. We estimate these PSF parameters for this ill-posed class of inverse problem from raw data, along with the regularization parameters required to stabilize the solution, using the generalized cross-validation method (GCV). We propose efficient approximation techniques based on the Lanczos algorithm and Gauss quadrature theory, reducing the computational complexity of the GCV. Data-driven PSF and regularization parameter estimation experiments with synthetic and real image sequences are presented to demonstrate the effectiveness and robustness of our method.

  8. Asymptotic optimality and efficient computation of the leave-subject-out cross-validation

    KAUST Repository

    Xu, Ganggang; Huang, Jianhua Z.

    2012-01-01

    Although the leave-subject-out cross-validation (CV) has been widely used in practice for tuning parameter selection for various nonparametric and semiparametric models of longitudinal data, its theoretical property is unknown and solving the associated optimization problem is computationally expensive, especially when there are multiple tuning parameters. In this paper, by focusing on the penalized spline method, we show that the leave-subject-out CV is optimal in the sense that it is asymptotically equivalent to the empirical squared error loss function minimization. An efficient Newton-type algorithm is developed to compute the penalty parameters that optimize the CV criterion. Simulated and real data are used to demonstrate the effectiveness of the leave-subject-out CV in selecting both the penalty parameters and the working correlation matrix. © 2012 Institute of Mathematical Statistics.

  9. Evaluation of Analysis by Cross-Validation, Part II: Diagnostic and Optimization of Analysis Error Covariance

    Directory of Open Access Journals (Sweden)

    Richard Ménard

    2018-02-01

    Full Text Available We present a general theory of estimation of analysis error covariances based on cross-validation as well as a geometric interpretation of the method. In particular, we use the variance of passive observation-minus-analysis residuals and show that the true analysis error variance can be estimated, without relying on the optimality assumption. This approach is used to obtain near optimal analyses that are then used to evaluate the air quality analysis error using several different methods at active and passive observation sites. We compare the estimates according to the method of Hollingsworth-Lönnberg, Desroziers et al., a new diagnostic we developed, and the perceived analysis error computed from the analysis scheme, to conclude that, as long as the analysis is near optimal, all estimates agree within a certain error margin.

  10. [ILCOR recommendation on signage of automated external defibrillators (AEDs)].

    Science.gov (United States)

    Truhlár, A

    2010-05-01

    Early defibrillation is a determinant of survival in both out-of-hospital and in-hospital cardiac arrests from ventricular fibrillation and pulseless ventricular tachycardia. The review summarizes importance of early defibrillation with automated external defibrillators (AED) and presents the International Liaison Committee on Resuscitation (ILCOR) recommendation for universal AED sign. The aim of the recommendation is to unify the AED signs worldwide and to spread the knowledge of this. The public in general, but healthcare professionals particularly, should be able to recognize AED location and use the device immediately in case of cardiac arrest.

  11. Genoplivning med automatisk ekstern defibrillator på hospital

    DEFF Research Database (Denmark)

    Løfgren, Bo; Wahlgreen, Claus; Hoffmann, Anne Mette

    2009-01-01

    Early defibrillation is a determinant of survival in cardiac arrest. We report a Danish case of successful in-hospital resuscitation using an automated external defibrillator (AED). This case illustrates important aspects of implementation of in-hospital use of an AED, i.e. location of the AED......, education of the staff, systematic registration and data collection and technical aspects of AED use. If in-hospital AED implementation is carefully executed, its use may provide a safe and effective way of obtaining early defibrillation. Udgivelsesdato: 2009-Jan-26...

  12. Diversity shrinkage: Cross-validating pareto-optimal weights to enhance diversity via hiring practices.

    Science.gov (United States)

    Song, Q Chelsea; Wee, Serena; Newman, Daniel A

    2017-12-01

    To reduce adverse impact potential and improve diversity outcomes from personnel selection, one promising technique is De Corte, Lievens, and Sackett's (2007) Pareto-optimal weighting strategy. De Corte et al.'s strategy has been demonstrated on (a) a composite of cognitive and noncognitive (e.g., personality) tests (De Corte, Lievens, & Sackett, 2008) and (b) a composite of specific cognitive ability subtests (Wee, Newman, & Joseph, 2014). Both studies illustrated how Pareto-weighting (in contrast to unit weighting) could lead to substantial improvement in diversity outcomes (i.e., diversity improvement), sometimes more than doubling the number of job offers for minority applicants. The current work addresses a key limitation of the technique-the possibility of shrinkage, especially diversity shrinkage, in the Pareto-optimal solutions. Using Monte Carlo simulations, sample size and predictor combinations were varied and cross-validated Pareto-optimal solutions were obtained. Although diversity shrinkage was sizable for a composite of cognitive and noncognitive predictors when sample size was at or below 500, diversity shrinkage was typically negligible for a composite of specific cognitive subtest predictors when sample size was at least 100. Diversity shrinkage was larger when the Pareto-optimal solution suggested substantial diversity improvement. When sample size was at least 100, cross-validated Pareto-optimal weights typically outperformed unit weights-suggesting that diversity improvement is often possible, despite diversity shrinkage. Implications for Pareto-optimal weighting, adverse impact, sample size of validation studies, and optimizing the diversity-job performance tradeoff are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. SU-E-T-231: Cross-Validation of 3D Gamma Comparison Tools

    International Nuclear Information System (INIS)

    Alexander, KM; Jechel, C; Pinter, C; Lasso, A; Fichtinger, G; Salomons, G; Schreiner, LJ

    2015-01-01

    Purpose: Moving the computational analysis for 3D gel dosimetry into the 3D Slicer (www.slicer.org) environment has made gel dosimetry more clinically accessible. To ensure accuracy, we cross-validate the 3D gamma comparison module in 3D Slicer with an independently developed algorithm using simulated and measured dose distributions. Methods: Two reference dose distributions were generated using the Varian Eclipse treatment planning system. The first distribution consisted of a four-field box irradiation delivered to a plastic water phantom and the second, a VMAT plan delivered to a gel dosimeter phantom. The first reference distribution was modified within Eclipse to create an evaluated dose distribution by spatially shifting one field by 3mm, increasing the monitor units of the second field, applying a dynamic wedge for the third field, and leaving the fourth field unchanged. The VMAT plan was delivered to a gel dosimeter and the evaluated dose in the gel was calculated from optical CT measurements. Results from the gamma comparison tool built into the SlicerRT toolbox were compared to results from our in-house gamma algorithm implemented in Matlab (via MatlabBridge in 3D Slicer). The effects of noise, resolution and the exchange of reference and evaluated designations on the gamma comparison were also examined. Results: Perfect agreement was found between the gamma results obtained using the SlicerRT tool and our Matlab implementation for both the four-field box and gel datasets. The behaviour of the SlicerRT comparison with respect to changes in noise, resolution and the role of the reference and evaluated dose distributions was consistent with previous findings. Conclusion: Two independently developed gamma comparison tools have been cross-validated and found to be identical. As we transition our gel dosimetry analysis from Matlab to 3D Slicer, this validation serves as an important test towards ensuring the consistency of dose comparisons using the 3D Slicer

  14. Cross-validation and Peeling Strategies for Survival Bump Hunting using Recursive Peeling Methods

    Science.gov (United States)

    Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J. Sunil

    2015-01-01

    We introduce a framework to build a survival/risk bump hunting model with a censored time-to-event response. Our Survival Bump Hunting (SBH) method is based on a recursive peeling procedure that uses a specific survival peeling criterion derived from non/semi-parametric statistics such as the hazards-ratio, the log-rank test or the Nelson--Aalen estimator. To optimize the tuning parameter of the model and validate it, we introduce an objective function based on survival or prediction-error statistics, such as the log-rank test and the concordance error rate. We also describe two alternative cross-validation techniques adapted to the joint task of decision-rule making by recursive peeling and survival estimation. Numerical analyses show the importance of replicated cross-validation and the differences between criteria and techniques in both low and high-dimensional settings. Although several non-parametric survival models exist, none addresses the problem of directly identifying local extrema. We show how SBH efficiently estimates extreme survival/risk subgroups unlike other models. This provides an insight into the behavior of commonly used models and suggests alternatives to be adopted in practice. Finally, our SBH framework was applied to a clinical dataset. In it, we identified subsets of patients characterized by clinical and demographic covariates with a distinct extreme survival outcome, for which tailored medical interventions could be made. An R package PRIMsrc (Patient Rule Induction Method in Survival, Regression and Classification settings) is available on CRAN (Comprehensive R Archive Network) and GitHub. PMID:27034730

  15. Cross-validation and hypothesis testing in neuroimaging: An irenic comment on the exchange between Friston and Lindquist et al.

    Science.gov (United States)

    Reiss, Philip T

    2015-08-01

    The "ten ironic rules for statistical reviewers" presented by Friston (2012) prompted a rebuttal by Lindquist et al. (2013), which was followed by a rejoinder by Friston (2013). A key issue left unresolved in this discussion is the use of cross-validation to test the significance of predictive analyses. This note discusses the role that cross-validation-based and related hypothesis tests have come to play in modern data analyses, in neuroimaging and other fields. It is shown that such tests need not be suboptimal and can fill otherwise-unmet inferential needs. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Cross Validation of Rain Drop Size Distribution between GPM and Ground Based Polarmetric radar

    Science.gov (United States)

    Chandra, C. V.; Biswas, S.; Le, M.; Chen, H.

    2017-12-01

    Dual-frequency precipitation radar (DPR) on board the Global Precipitation Measurement (GPM) core satellite has reflectivity measurements at two independent frequencies, Ku- and Ka- band. Dual-frequency retrieval algorithms have been developed traditionally through forward, backward, and recursive approaches. However, these algorithms suffer from "dual-value" problem when they retrieve medium volume diameter from dual-frequency ratio (DFR) in rain region. To this end, a hybrid method has been proposed to perform raindrop size distribution (DSD) retrieval for GPM using a linear constraint of DSD along rain profile to avoid "dual-value" problem (Le and Chandrasekar, 2015). In the current GPM level 2 algorithm (Iguchi et al. 2017- Algorithm Theoretical Basis Document) the Solver module retrieves a vertical profile of drop size distributionn from dual-frequency observations and path integrated attenuations. The algorithm details can be found in Seto et al. (2013) . On the other hand, ground based polarimetric radars have been used for a long time to estimate drop size distributions (e.g., Gorgucci et al. 2002 ). In addition, coincident GPM and ground based observations have been cross validated using careful overpass analysis. In this paper, we perform cross validation on raindrop size distribution retrieval from three sources, namely the hybrid method, the standard products from the solver module and DSD retrievals from ground polarimetric radars. The results are presented from two NEXRAD radars located in Dallas -Fort Worth, Texas (i.e., KFWS radar) and Melbourne, Florida (i.e., KMLB radar). The results demonstrate the ability of DPR observations to produce DSD estimates, which can be used subsequently to generate global DSD maps. References: Seto, S., T. Iguchi, T. Oki, 2013: The basic performance of a precipitation retrieval algorithm for the Global Precipitation Measurement mission's single/dual-frequency radar measurements. IEEE Transactions on Geoscience and

  17. Wide variation in cardiopulmonary resuscitation interruption intervals among commercially available automated external defibrillators may affect survival despite high defibrillation efficacy.

    Science.gov (United States)

    Snyder, David; Morgan, Carl

    2004-09-01

    Recent studies have associated interruptions of cardiopulmonary resuscitation imposed by automated external defibrillators (AEDs) with poor resuscitation outcome. In particular, the "hands-off" interval between precordial compressions and subsequent defibrillation shock has been implicated. We sought to determine the range of variation among current-generation AEDs with respect to this characteristic. Seven AEDs from six manufacturers were characterized via stopwatch and arrhythmia simulator with respect to the imposed hands-off interval. All AEDs were equipped with new batteries, and measurements were repeated five times for each AED. A wide variation in the hands-off interval between precordial compressions and shock delivery was observed, ranging from 5.2 to 28.4 secs, with only one AED achieving an interruption of <10 secs. Laboratory and clinical data suggest that this range of variation could be responsible for a more than two-fold variation in patient resuscitation success, an effect that far exceeds any defibrillation efficacy differences that may hypothetically exist. In addition to defibrillation waveform and dose, researchers should consider the hands-off cardiopulmonary resuscitation interruption interval between cardiopulmonary resuscitation and subsequent defibrillation shock to be an important covariate of outcome in resuscitation studies. Defibrillator design should minimize this interval to avoid potential adverse consequences on patient survival.

  18. Test-retest reliability and cross validation of the functioning everyday with a wheelchair instrument.

    Science.gov (United States)

    Mills, Tamara L; Holm, Margo B; Schmeler, Mark

    2007-01-01

    The purpose of this study was to establish the test-retest reliability and content validity of an outcomes tool designed to measure the effectiveness of seating-mobility interventions on the functional performance of individuals who use wheelchairs or scooters as their primary seating-mobility device. The instrument, Functioning Everyday With a Wheelchair (FEW), is a questionnaire designed to measure perceived user function related to wheelchair/scooter use. Using consumer-generated items, FEW Beta Version 1.0 was developed and test-retest reliability was established. Cross-validation of FEW Beta Version 1.0 was then carried out with five samples of seating-mobility users to establish content validity. Based on the content validity study, FEW Version 2.0 was developed and administered to seating-mobility consumers to examine its test-retest reliability. FEW Beta Version 1.0 yielded an intraclass correlation coefficient (ICC) Model (3,k) of .92, p content validity results revealed that FEW Beta Version 1.0 captured 55% of seating-mobility goals reported by consumers across five samples. FEW Version 2.0 yielded ICC(3,k) = .86, p content validity of FEW Version 2.0 was confirmed. FEW Beta Version 1.0 and FEW Version 2.0 were highly stable in their measurement of participants' seating-mobility goals over a 1-week interval.

  19. Sound quality indicators for urban places in Paris cross-validated by Milan data.

    Science.gov (United States)

    Ricciardi, Paola; Delaitre, Pauline; Lavandier, Catherine; Torchia, Francesca; Aumond, Pierre

    2015-10-01

    A specific smartphone application was developed to collect perceptive and acoustic data in Paris. About 3400 questionnaires were analyzed, regarding the global sound environment characterization, the perceived loudness of some emergent sources and the presence time ratio of sources that do not emerge from the background. Sound pressure level was recorded each second from the mobile phone's microphone during a 10-min period. The aim of this study is to propose indicators of urban sound quality based on linear regressions with perceptive variables. A cross validation of the quality models extracted from Paris data was carried out by conducting the same survey in Milan. The proposed sound quality general model is correlated with the real perceived sound quality (72%). Another model without visual amenity and familiarity is 58% correlated with perceived sound quality. In order to improve the sound quality indicator, a site classification was performed by Kohonen's Artificial Neural Network algorithm, and seven specific class models were developed. These specific models attribute more importance on source events and are slightly closer to the individual data than the global model. In general, the Parisian models underestimate the sound quality of Milan environments assessed by Italian people.

  20. Application of Monte Carlo cross-validation to identify pathway cross-talk in neonatal sepsis.

    Science.gov (United States)

    Zhang, Yuxia; Liu, Cui; Wang, Jingna; Li, Xingxia

    2018-03-01

    To explore genetic pathway cross-talk in neonates with sepsis, an integrated approach was used in this paper. To explore the potential relationships between differently expressed genes between normal uninfected neonates and neonates with sepsis and pathways, genetic profiling and biologic signaling pathway were first integrated. For different pathways, the score was obtained based upon the genetic expression by quantitatively analyzing the pathway cross-talk. The paired pathways with high cross-talk were identified by random forest classification. The purpose of the work was to find the best pairs of pathways able to discriminate sepsis samples versus normal samples. The results found 10 pairs of pathways, which were probably able to discriminate neonates with sepsis versus normal uninfected neonates. Among them, the best two paired pathways were identified according to analysis of extensive literature. Impact statement To find the best pairs of pathways able to discriminate sepsis samples versus normal samples, an RF classifier, the DS obtained by DEGs of paired pathways significantly associated, and Monte Carlo cross-validation were applied in this paper. Ten pairs of pathways were probably able to discriminate neonates with sepsis versus normal uninfected neonates. Among them, the best two paired pathways ((7) IL-6 Signaling and Phospholipase C Signaling (PLC); (8) Glucocorticoid Receptor (GR) Signaling and Dendritic Cell Maturation) were identified according to analysis of extensive literature.

  1. Compressive Sensing with Cross-Validation and Stop-Sampling for Sparse Polynomial Chaos Expansions

    Energy Technology Data Exchange (ETDEWEB)

    Huan, Xun; Safta, Cosmin; Sargsyan, Khachik; Vane, Zachary Phillips; Lacaze, Guilhem; Oefelein, Joseph C.; Najm, Habib N.

    2017-07-01

    Compressive sensing is a powerful technique for recovering sparse solutions of underdetermined linear systems, which is often encountered in uncertainty quanti cation analysis of expensive and high-dimensional physical models. We perform numerical investigations employing several com- pressive sensing solvers that target the unconstrained LASSO formulation, with a focus on linear systems that arise in the construction of polynomial chaos expansions. With core solvers of l1 ls, SpaRSA, CGIST, FPC AS, and ADMM, we develop techniques to mitigate over tting through an automated selection of regularization constant based on cross-validation, and a heuristic strategy to guide the stop-sampling decision. Practical recommendations on parameter settings for these tech- niques are provided and discussed. The overall method is applied to a series of numerical examples of increasing complexity, including large eddy simulations of supersonic turbulent jet-in-cross flow involving a 24-dimensional input. Through empirical phase-transition diagrams and convergence plots, we illustrate sparse recovery performance under structures induced by polynomial chaos, accuracy and computational tradeoffs between polynomial bases of different degrees, and practi- cability of conducting compressive sensing for a realistic, high-dimensional physical application. Across test cases studied in this paper, we find ADMM to have demonstrated empirical advantages through consistent lower errors and faster computational times.

  2. The cross-validated AUC for MCP-logistic regression with high-dimensional data.

    Science.gov (United States)

    Jiang, Dingfeng; Huang, Jian; Zhang, Ying

    2013-10-01

    We propose a cross-validated area under the receiving operator characteristic (ROC) curve (CV-AUC) criterion for tuning parameter selection for penalized methods in sparse, high-dimensional logistic regression models. We use this criterion in combination with the minimax concave penalty (MCP) method for variable selection. The CV-AUC criterion is specifically designed for optimizing the classification performance for binary outcome data. To implement the proposed approach, we derive an efficient coordinate descent algorithm to compute the MCP-logistic regression solution surface. Simulation studies are conducted to evaluate the finite sample performance of the proposed method and its comparison with the existing methods including the Akaike information criterion (AIC), Bayesian information criterion (BIC) or Extended BIC (EBIC). The model selected based on the CV-AUC criterion tends to have a larger predictive AUC and smaller classification error than those with tuning parameters selected using the AIC, BIC or EBIC. We illustrate the application of the MCP-logistic regression with the CV-AUC criterion on three microarray datasets from the studies that attempt to identify genes related to cancers. Our simulation studies and data examples demonstrate that the CV-AUC is an attractive method for tuning parameter selection for penalized methods in high-dimensional logistic regression models.

  3. Assessing behavioural changes in ALS: cross-validation of ALS-specific measures.

    Science.gov (United States)

    Pinto-Grau, Marta; Costello, Emmet; O'Connor, Sarah; Elamin, Marwa; Burke, Tom; Heverin, Mark; Pender, Niall; Hardiman, Orla

    2017-07-01

    The Beaumont Behavioural Inventory (BBI) is a behavioural proxy report for the assessment of behavioural changes in ALS. This tool has been validated against the FrSBe, a non-ALS-specific behavioural assessment, and further comparison of the BBI against a disease-specific tool was considered. This study cross-validates the BBI against the ALS-FTD-Q. Sixty ALS patients, 8% also meeting criteria for FTD, were recruited. All patients were evaluated using the BBI and the ALS-FTD-Q, completed by a carer. Correlational analysis was performed to assess construct validity. Precision, sensitivity, specificity, and overall accuracy of the BBI when compared to the ALS-FTD-Q, were obtained. The mean score of the whole sample on the BBI was 11.45 ± 13.06. ALS-FTD patients scored significantly higher than non-demented ALS patients (31.6 ± 14.64, 9.62 ± 11.38; p ALS-FTD-Q was observed (r = 0.807, p ALS-FTD-Q. Good construct validity has been further confirmed when the BBI is compared to an ALS-specific tool. Furthermore, the BBI is a more comprehensive behavioural assessment for ALS, as it measures the whole behavioural spectrum in this condition.

  4. A Cross-Validation Study of the Kirton Adaption-Innovation Inventory in Three Research and Development Organizations.

    Science.gov (United States)

    Keller, Robert T.; Holland, Winford E.

    1979-01-01

    A cross-validation study of the Kirton Adaption-Innovation Inventory (KAI) was conducted with 256 professional employees from three applied research and development organizations. The KAI correlated well with both direct and indirect measures of innovativeness in all three organizations. (Author/MH)

  5. Development and Cross-Validation of Equation for Estimating Percent Body Fat of Korean Adults According to Body Mass Index

    Directory of Open Access Journals (Sweden)

    Hoyong Sung

    2017-06-01

    Full Text Available Background : Using BMI as an independent variable is the easiest way to estimate percent body fat. Thus far, few studies have investigated the development and cross-validation of an equation for estimating the percent body fat of Korean adults according to the BMI. The goals of this study were the development and cross-validation of an equation for estimating the percent fat of representative Korean adults using the BMI. Methods : Samples were obtained from the Korea National Health and Nutrition Examination Survey between 2008 and 2011. The samples from 2008-2009 and 2010-2011 were labeled as the validation group (n=10,624 and the cross-validation group (n=8,291, respectively. The percent fat was measured using dual-energy X-ray absorptiometry, and the body mass index, gender, and age were included as independent variables to estimate the measured percent fat. The coefficient of determination (R², standard error of estimation (SEE, and total error (TE were calculated to examine the accuracy of the developed equation. Results : The cross-validated R² was 0.731 for Model 1 and 0.735 for Model 2. The SEE was 3.978 for Model 1 and 3.951 for Model 2. The equations developed in this study are more accurate for estimating percent fat of the cross-validation group than those previously published by other researchers. Conclusion : The newly developed equations are comparatively accurate for the estimation of the percent fat of Korean adults.

  6. Cross-validity of a portable glucose capillary monitors in relation to enzymatic spectrophotometer methods

    Directory of Open Access Journals (Sweden)

    William Alves Lima

    2006-09-01

    Full Text Available The glucose is an important substrate utilizaded during exercise. Accurate measurement of glucose is vital to obtain trustworthy results. The enzymatic spectrophotometer methods are generally considered the “goldstandard” laboratory procedure for measuring of glucose (GEnz, is time consuming, costly, and inappropriate for large scale field testing. Compact and portable glucose monitors (GAccu are quick and easy methods to assess glucose on large numbers of subjects. So, this study aimed to test the cross-validity of GAccu. The sample was composed of 107 men (aged= 35.4±10.7 years; stature= 168.4±6.9 cm; body mass= 73.4±11.2 kg; %fat= 20.9±8.3% – by dual energy x-ray absorptiometry. Blood for measuring fasting glucose was taken in basilar vein (Genz, Bioplus: Bio-2000 and in ring finger (GAccu: Accu-Chek© Advantage©, after a 12-hour overnight fast. GEnz was used as the criterion for cross-validity. Paired t-test shown differences (p RESUMO A glicose é um substrato importante utilizado durante o exercício físico. Medidas acuradas da glicose são fundamentais para a obtenção de resultados confiáveis. O método laboratorial de espectrofotometria enzimática geralmente é considerado o procedimento “padrão ouro” para medir a glicose (GEnz, o qual requer tempo, custo e é inapropriado para o uso em larga escala. Monitores portáteis de glicose (GAccu são rápidos e fáceis para medir a glicose em um grande número de sujeitos. Então, este estudo teve por objetivo testar a validade concorrente do GAccu. A amostra foi composta por 107 homens (idade= 35,4±10,7 anos; estatura= 168,4±6,9 cm; massa corporal= 73,4±11,2 kg; %gordura= 20,9±8,3% – por absortometria de raio-x de dupla energia. O sangue para mensurar a glicose em jejum foi tirado na veia basilar (Genz, Bioplus: Bio-2000 e no dedo anular (GAccu - Accu- Chek© Advantage©, depois de 12h de jejum noturno. O GEnz foi usado como critério para testar a validade

  7. Out-of-hospital cardiac arrest: Probability of bystander defibrillation relative to distance to nearest automated external defibrillator.

    Science.gov (United States)

    Sondergaard, Kathrine B; Hansen, Steen Moller; Pallisgaard, Jannik L; Gerds, Thomas Alexander; Wissenberg, Mads; Karlsson, Lena; Lippert, Freddy K; Gislason, Gunnar H; Torp-Pedersen, Christian; Folke, Fredrik

    2018-03-01

    Despite wide dissemination of automated external defibrillators (AEDs), bystander defibrillation rates remain low. We aimed to investigate how route distance to the nearest accessible AED was associated with probability of bystander defibrillation in public and residential locations. We used data from the nationwide Danish Cardiac Arrest Registry and the Danish AED Network to identify out-of-hospital cardiac arrests and route distances to nearest accessible registered AED during 2008-2013. The association between route distance and bystander defibrillation was described using restricted cubic spline logistic regression. We included 6971 out-of-hospital cardiac arrest cases. The proportion of arrests according to distance in meters (≤100, 101-200, >200) to the nearest accessible AED was: 4.6% (n=320), 5.3% (n=370), and 90.1% (n=6281), respectively. For cardiac arrests in public locations, the probability of bystander defibrillation at 0, 100 and 200m from the nearest AED was 35.7% (95% confidence interval 28.0%-43.5%), 21.3% (95% confidence interval 17.4%-25.2%), and 13.7% (95% confidence interval 10.1%-16.8%), respectively. The corresponding numbers for cardiac arrests in residential locations were 7.0% (95% confidence interval -2.1%-16.1%), 1.5% (95% confidence interval 0.002%-2.8%), and 0.9% (95% confidence interval 0.0005%-1.7%), respectively. In public locations, the probability of bystander defibrillation decreased rapidly within the first 100m route distance from cardiac arrest to nearest accessible AED whereas the probability of bystander defibrillation was low for all distances in residential areas. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Vascular Adaptation: Pattern Formation and Cross Validation between an Agent Based Model and a Dynamical System.

    Science.gov (United States)

    Garbey, Marc; Casarin, Stefano; Berceli, Scott A

    2017-09-21

    Myocardial infarction is the global leading cause of mortality (Go et al., 2014). Coronary artery occlusion is its main etiology and it is commonly treated by Coronary Artery Bypass Graft (CABG) surgery (Wilson et al, 2007). The long-term outcome remains unsatisfactory (Benedetto, 2016) as the graft faces the phenomenon of restenosis during the post-surgery, which consists of re-occlusion of the lumen and usually requires secondary intervention even within one year after the initial surgery (Harskamp, 2013). In this work, we propose an extensive study of the restenosis phenomenon by implementing two mathematical models previously developed by our group: a heuristic Dynamical System (DS) (Garbey and Berceli, 2013), and a stochastic Agent Based Model (ABM) (Garbey et al., 2015). With an extensive use of the ABM, we retrieved the pattern formations of the cellular events that mainly lead the restenosis, especially focusing on mitosis in intima, caused by alteration in shear stress, and mitosis in media, fostered by alteration in wall tension. A deep understanding of the elements at the base of the restenosis is indeed crucial in order to improve the final outcome of vein graft bypass. We also turned the ABM closer to the physiological reality by abating its original assumption of circumferential symmetry. This allowed us to finely replicate the trigger event of the restenosis, i.e. the loss of the endothelium in the early stage of the post-surgical follow up (Roubos et al., 1995) and to simulate the encroachment of the lumen in a fashion aligned with histological evidences (Owens et al., 2015). Finally, we cross-validated the two models by creating an accurate matching procedure. In this way we added the degree of accuracy given by the ABM to a simplified model (DS) that can serve as powerful predictive tool for the clinic. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Development and Cross-Validation of the Short Form of the Cultural Competence Scale for Nurses

    Directory of Open Access Journals (Sweden)

    Duckhee Chae, PhD, RN

    2018-03-01

    Full Text Available Purpose: To develop and validate the short form of the Korean adaptation of the Cultural Competence Scale for Nurses. Methods: To shorten the 33-item Cultural Competence Scale for Nurses, an expert panel (N = 6 evaluated its content validity. The revised items were pilot tested using a sample of nine nurses, and clarity was assessed through cognitive interviews with respondents. The original instrument was shortened and validated through item analysis, exploratory factor analysis, convergent validity, and reliability using data from 277 hospital nurses. The 14-item final version was cross-validated through confirmatory factor analysis, convergent validity, discriminant validity, known-group comparisons, and reliability using data from 365 nurses belonging to 19 hospitals. Results: A 4-factor, 14-item model demonstrated satisfactory fit with significant factor loadings. The convergent validity between the developed tool and transcultural self-efficacy was significant (r = .55, p < .001. The convergent validity evaluated using the Average Variance Extracted and discriminant validity were acceptable. Known-group comparisons revealed significant differences in the mean scores of the groups who spent more than one month abroad (p = .002 were able to communicate in a foreign language (p < .001 and had education to care for foreign patients (p = .039. Cronbach's α was .89, and the reliability of the subscales ranged from .74 to .91. Conclusion: The Cultural Competence Scale for Nurses-Short Form demonstrated good reliability and validity. It is a short and appropriate instrument for use in clinical and research settings to assess nurses' cultural competence. Keywords: cultural competence, psychometric properties, nurse

  10. Cross Validation Through Two-Dimensional Solution Surface for Cost-Sensitive SVM.

    Science.gov (United States)

    Gu, Bin; Sheng, Victor S; Tay, Keng Yeow; Romano, Walter; Li, Shuo

    2017-06-01

    Model selection plays an important role in cost-sensitive SVM (CS-SVM). It has been proven that the global minimum cross validation (CV) error can be efficiently computed based on the solution path for one parameter learning problems. However, it is a challenge to obtain the global minimum CV error for CS-SVM based on one-dimensional solution path and traditional grid search, because CS-SVM is with two regularization parameters. In this paper, we propose a solution and error surfaces based CV approach (CV-SES). More specifically, we first compute a two-dimensional solution surface for CS-SVM based on a bi-parameter space partition algorithm, which can fit solutions of CS-SVM for all values of both regularization parameters. Then, we compute a two-dimensional validation error surface for each CV fold, which can fit validation errors of CS-SVM for all values of both regularization parameters. Finally, we obtain the CV error surface by superposing K validation error surfaces, which can find the global minimum CV error of CS-SVM. Experiments are conducted on seven datasets for cost sensitive learning and on four datasets for imbalanced learning. Experimental results not only show that our proposed CV-SES has a better generalization ability than CS-SVM with various hybrids between grid search and solution path methods, and than recent proposed cost-sensitive hinge loss SVM with three-dimensional grid search, but also show that CV-SES uses less running time.

  11. Estimating misclassification error: a closer look at cross-validation based methods

    Directory of Open Access Journals (Sweden)

    Ounpraseuth Songthip

    2012-11-01

    Full Text Available Abstract Background To estimate a classifier’s error in predicting future observations, bootstrap methods have been proposed as reduced-variation alternatives to traditional cross-validation (CV methods based on sampling without replacement. Monte Carlo (MC simulation studies aimed at estimating the true misclassification error conditional on the training set are commonly used to compare CV methods. We conducted an MC simulation study to compare a new method of bootstrap CV (BCV to k-fold CV for estimating clasification error. Findings For the low-dimensional conditions simulated, the modest positive bias of k-fold CV contrasted sharply with the substantial negative bias of the new BCV method. This behavior was corroborated using a real-world dataset of prognostic gene-expression profiles in breast cancer patients. Our simulation results demonstrate some extreme characteristics of variance and bias that can occur due to a fault in the design of CV exercises aimed at estimating the true conditional error of a classifier, and that appear not to have been fully appreciated in previous studies. Although CV is a sound practice for estimating a classifier’s generalization error, using CV to estimate the fixed misclassification error of a trained classifier conditional on the training set is problematic. While MC simulation of this estimation exercise can correctly represent the average bias of a classifier, it will overstate the between-run variance of the bias. Conclusions We recommend k-fold CV over the new BCV method for estimating a classifier’s generalization error. The extreme negative bias of BCV is too high a price to pay for its reduced variance.

  12. Evidence-based cross validation for acoustic power transmission for a novel treatment system.

    Science.gov (United States)

    Mihcin, Senay; Strehlow, Jan; Demedts, Daniel; Schwenke, Michael; Levy, Yoav; Melzer, Andreas

    2017-06-01

    The novel Trans-Fusimo Treatment System (TTS) is designed to control Magnetic Resonance guided Focused Ultrasound (MRgFUS) therapy to ablate liver tumours under respiratory motion. It is crucial to deliver the acoustic power within tolerance limits for effective liver tumour treatment via MRgFUS. Before application in a clinical setting, evidence of reproducibility and reliability is a must for safe practice. The TTS software delivers the acoustic power via ExAblate-2100 Conformal Bone System (CBS) transducer. A built-in quality assurance application was developed to measure the force values, using a novel protocol to measure the efficiency for the electrical power values of 100 and 150W for 6s of sonication. This procedure was repeated 30 times by two independent users against the clinically approved ExAblate-2100 CBS for cross-validation. Both systems proved to deliver the power within the accepted efficiency levels (70-90%). Two sample t-tests were used to assess the differences in force values between the ExAblate-2100 CBS and the TTS (p > 0.05). Bland-Altman plots were used to demonstrate the limits of agreement between the two systems falling within the 10% limits of agreement. Two sample t-tests indicated that TTS does not have user dependency (p > 0.05). The TTS software proved to deliver the acoustic power without exceeding the safety levels. Results provide evidence as a part of ISO13485 regulations for CE marking purposes. The developed methodology could be utilised as a part of quality assurance system in clinical settings; when the TTS is used in clinical practice.

  13. Use a defibrillator, save a life

    CERN Multimedia

    Joannah Caborn Wengler

    2012-01-01

    With the work for Long Shutdown 1 looming on the horizon, the CERN Fire Brigade is anticipating a heavy workload: more people working at CERN means more call-outs. So the more trained first-aiders around to help out before the paramedics arrive, the better. Would you know what to do in a medical emergency?   It could happen at any time: two colleagues are having a coffee at work, when one suddenly clutches his or her chest and falls to the floor unconscious. What would you do? Run to find a first-aider? Call the ambulance and wait, finishing your coffee? Neither response is entirely correct. On Monday 11 June in Building 40 the CMS safety group, in collaboration with the Fire Brigade and the Medical Service, demonstrated the recommended, potentially life-saving response to cardiac arrest (see the video), including the correct use of a defibrillator, ten of which were recently installed in key CERN locations (the Bulletin reported).     “In countries where...

  14. Defibrillator implantations for primary prevention in the United States: Inappropriate care or inadequate documentation: Insights from the National Cardiovascular Data ICD Registry.

    Science.gov (United States)

    Kaiser, Daniel W; Tsai, Vivian; Heidenreich, Paul A; Goldstein, Mary K; Wang, Yongfei; Curtis, Jeptha; Turakhia, Mintu P

    2015-10-01

    Prior studies have reported that more than 20% of implantable cardioverter-defibrillator (ICD) implantations in the United States do not adhere to trial-based criteria. We sought to investigate the patient characteristics associated with not meeting the inclusion criteria of the clinical trials that have demonstrated the efficacy of primary prevention ICDs. Using data from the National Cardiovascular Data Registry's ICD Registry, we identified patients who received ICDs for primary prevention from January 2006 to December 2008. We determined whether patients met the inclusion criteria of at least 1 of the 4 ICD primary prevention trials: Multicenter Automatic Defibrillator Implantation Trial (MADIT), MADIT-II, Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), and the Multicenter Unsustained Tachycardia Trial (MUSTT). Among 150,264 patients, 86% met criteria for an ICD implantation based on trial data. The proportion of patients who did not meet trial-based criteria increased as age decreased. In multivariate analysis, the significant predictors for not meeting trial criteria included prior cardiac transplantation (odds ratio [OR] 2.1), pediatric electrophysiology operator (OR 2.0), and high-grade atrioventricular conduction disease (OR 1.4). Among National Cardiovascular Data Registry registrants receiving first-time ICDs for primary prevention, the majority met trial-based criteria. Multivariate analyses suggested that many patients who did not meet the trial-based criteria may have had clinical circumstances that warranted ICD implantation. These findings caution against the use of trial-based indications to determine site quality metrics that could penalize sites that care for younger patients. The planned incorporation of appropriate use criteria into the ICD registry may better characterize patient- and site-level quality and performance. Published by Elsevier Inc.

  15. The challenges and possibilities of public access defibrillation

    DEFF Research Database (Denmark)

    Ringh, Mattias; Hollenberg, Jacob; Palsgaard-Moeller, Thea

    2018-01-01

    . Much hope has been put to the concept of Public Access Defibrillation with a massive dissemination of public available AEDs throughout most western countries. Accordingly, current guidelines recommend that AEDs should be deployed in places with a high likelihood of OHCA. Despite these efforts, AED use...... is in most settings anecdotal with little effect on overall OHCA survival. The major reasons for low use of public AEDs are that most OHCA take place outside high incidence sites of cardiac arrest and that most OHCAs take place in residential settings, currently defined as not suitable for Public Access...... Defibrillation. However, the use of new technology for identification and recruitment of lay bystanders and nearby AEDs to the scene of the cardiac arrest as well as new methods for strategic AED placement redefines and challenges the current concept and definitions of Public Access Defibrillation. Existing...

  16. Praehospital-hjertestopbehandling med semiautomatisk defibrillator--Heartstart 2000

    DEFF Research Database (Denmark)

    Fonsmark, L; Sandøe, E; Kastrup, J

    1989-01-01

    %. No practical problems of note occurred in connection with employment of the defibrillator. The ambulance staffs underwent six hours of training and this appeared to be adequate. It is concluded that Heartstart 2000 functions well and effectively in connection with revival of patients with cardiac arrest......In order to test the efficacy of a semiautomatic defibrillator (Heartstart 2000) in connection with cardiac arrest outside hospital, the apparatus was installed in two of the ambulances belonging to the Copenhagen Fire Service. The ambulance district involved was also equipped with an ambulance...... staffed by a doctor. A total of 48 patients with cardiac arrest were found and 16 of these had ventricular fibrillation. Six of the 16 patients have since been discharged from hospital (37.5%). The defibrillator had a high diagnostic certainty with a sensitivity of 96.5% and a specificity of 100...

  17. Comparison of the Effects of Cross-validation Methods on Determining Performances of Classifiers Used in Diagnosing Congestive Heart Failure

    Directory of Open Access Journals (Sweden)

    Isler Yalcin

    2015-08-01

    Full Text Available Congestive heart failure (CHF occurs when the heart is unable to provide sufficient pump action to maintain blood flow to meet the needs of the body. Early diagnosis is important since the mortality rate of the patients with CHF is very high. There are different validation methods to measure performances of classifier algorithms designed for this purpose. In this study, k-fold and leave-one-out cross-validation methods were tested for performance measures of five distinct classifiers in the diagnosis of the patients with CHF. Each algorithm was run 100 times and the average and the standard deviation of classifier performances were recorded. As a result, it was observed that average performance was enhanced and the variability of performances was decreased when the number of data sections used in the cross-validation method was increased.

  18. Cross-validation analysis for genetic evaluation models for ranking in endurance horses.

    Science.gov (United States)

    García-Ballesteros, S; Varona, L; Valera, M; Gutiérrez, J P; Cervantes, I

    2018-01-01

    Ranking trait was used as a selection criterion for competition horses to estimate racing performance. In the literature the most common approaches to estimate breeding values are the linear or threshold statistical models. However, recent studies have shown that a Thurstonian approach was able to fix the race effect (competitive level of the horses that participate in the same race), thus suggesting a better prediction accuracy of breeding values for ranking trait. The aim of this study was to compare the predictability of linear, threshold and Thurstonian approaches for genetic evaluation of ranking in endurance horses. For this purpose, eight genetic models were used for each approach with different combinations of random effects: rider, rider-horse interaction and environmental permanent effect. All genetic models included gender, age and race as systematic effects. The database that was used contained 4065 ranking records from 966 horses and that for the pedigree contained 8733 animals (47% Arabian horses), with an estimated heritability around 0.10 for the ranking trait. The prediction ability of the models for racing performance was evaluated using a cross-validation approach. The average correlation between real and predicted performances across genetic models was around 0.25 for threshold, 0.58 for linear and 0.60 for Thurstonian approaches. Although no significant differences were found between models within approaches, the best genetic model included: the rider and rider-horse random effects for threshold, only rider and environmental permanent effects for linear approach and all random effects for Thurstonian approach. The absolute correlations of predicted breeding values among models were higher between threshold and Thurstonian: 0.90, 0.91 and 0.88 for all animals, top 20% and top 5% best animals. For rank correlations these figures were 0.85, 0.84 and 0.86. The lower values were those between linear and threshold approaches (0.65, 0.62 and 0.51). In

  19. Cultural Orientations Framework (COF) Assessment Questionnaire in Cross-Cultural Coaching: A Cross-Validation with Wave Focus Styles

    OpenAIRE

    Rojon, C; McDowall, A

    2010-01-01

    This paper outlines a cross-validation of the Cultural Orientations Framework assessment questionnaire\\ud (COF, Rosinski, 2007; a new tool designed for cross-cultural coaching) with the Saville Consulting\\ud Wave Focus Styles questionnaire (Saville Consulting, 2006; an existing validated measure of\\ud occupational personality), using data from UK and German participants (N = 222). The convergent and\\ud divergent validity of the questionnaire was adequate. Contrary to previous findings which u...

  20. Screening for postdeployment conditions: development and cross-validation of an embedded validity scale in the neurobehavioral symptom inventory.

    Science.gov (United States)

    Vanderploeg, Rodney D; Cooper, Douglas B; Belanger, Heather G; Donnell, Alison J; Kennedy, Jan E; Hopewell, Clifford A; Scott, Steven G

    2014-01-01

    To develop and cross-validate internal validity scales for the Neurobehavioral Symptom Inventory (NSI). Four existing data sets were used: (1) outpatient clinical traumatic brain injury (TBI)/neurorehabilitation database from a military site (n = 403), (2) National Department of Veterans Affairs TBI evaluation database (n = 48 175), (3) Florida National Guard nonclinical TBI survey database (n = 3098), and (4) a cross-validation outpatient clinical TBI/neurorehabilitation database combined across 2 military medical centers (n = 206). Secondary analysis of existing cohort data to develop (study 1) and cross-validate (study 2) internal validity scales for the NSI. The NSI, Mild Brain Injury Atypical Symptoms, and Personality Assessment Inventory scores. Study 1: Three NSI validity scales were developed, composed of 5 unusual items (Negative Impression Management [NIM5]), 6 low-frequency items (LOW6), and the combination of 10 nonoverlapping items (Validity-10). Cut scores maximizing sensitivity and specificity on these measures were determined, using a Mild Brain Injury Atypical Symptoms score of 8 or more as the criterion for invalidity. Study 2: The same validity scale cut scores again resulted in the highest classification accuracy and optimal balance between sensitivity and specificity in the cross-validation sample, using a Personality Assessment Inventory Negative Impression Management scale with a T score of 75 or higher as the criterion for invalidity. The NSI is widely used in the Department of Defense and Veterans Affairs as a symptom-severity assessment following TBI, but is subject to symptom overreporting or exaggeration. This study developed embedded NSI validity scales to facilitate the detection of invalid response styles. The NSI Validity-10 scale appears to hold considerable promise for validity assessment when the NSI is used as a population-screening tool.

  1. Praehospital-hjertestopbehandling med semiautomatisk defibrillator--Heartstart 2000

    DEFF Research Database (Denmark)

    Fonsmark, L; Sandøe, E; Kastrup, J

    1989-01-01

    staffed by a doctor. A total of 48 patients with cardiac arrest were found and 16 of these had ventricular fibrillation. Six of the 16 patients have since been discharged from hospital (37.5%). The defibrillator had a high diagnostic certainty with a sensitivity of 96.5% and a specificity of 100......%. No practical problems of note occurred in connection with employment of the defibrillator. The ambulance staffs underwent six hours of training and this appeared to be adequate. It is concluded that Heartstart 2000 functions well and effectively in connection with revival of patients with cardiac arrest...

  2. Determinants of geographic variations in implantation of cardiac defibrillators in the European Society of Cardiology member countries--data from the European Heart Rhythm Association White Book.

    Science.gov (United States)

    Lubinski, Andrzej; Bissinger, Andrzej; Boersma, Lucas; Leenhardt, Antoine; Merkely, Bela; Oto, Ali; Proclemer, Alessandro; Brugada, Josep; Vardas, Panos E; Wolpert, Christian

    2011-05-01

    Sudden cardiac death (SCD) is a major health concern in developed countries. Many studies have demonstrated the efficacy of implantable cardioverter defibrillator (ICD) therapy in the prevention of SCD and total mortality reduction. However, the high individual costs and the reimbursement policy may limit widespread ICD utilization. This study analyzed the temporal and the geographical trends of the ICD implantation rate. Data were gathered from two editions of the European Heart Rhythm Association (EHRA) White Books published in 2008 and 2009. The analysis revealed significant differences in the rates of ICD implantation per million capita between the countries, but the median implantations was constantly increasing. The number of ICD implantations correlated with gross domestic product (GDP), GDP per capita, expenditure on health, life expectancy, and the number of implanting centres. There are great number of differences in the ICD-implanting rates between EHRA member countries, consequent to the increase in the number of ICD implantations. The ICD implantation rates are related to national economic status and healthcare expenses.

  3. Testing of Anesthesia Machines and Defibrillators in Healthcare Institutions.

    Science.gov (United States)

    Gurbeta, Lejla; Dzemic, Zijad; Bego, Tamer; Sejdic, Ervin; Badnjevic, Almir

    2017-09-01

    To improve the quality of patient treatment by improving the functionality of medical devices in healthcare institutions. To present the results of the safety and performance inspection of patient-relevant output parameters of anesthesia machines and defibrillators defined by legal metrology. This study covered 130 anesthesia machines and 161 defibrillators used in public and private healthcare institutions, during a period of two years. Testing procedures were carried out according to international standards and legal metrology legislative procedures in Bosnia and Herzegovina. The results show that in 13.84% of tested anesthesia machine and 14.91% of defibrillators device performance is not in accordance with requirements and should either have its results be verified, or the device removed from use or scheduled for corrective maintenance. Research emphasizes importance of independent safety and performance inspections, and gives recommendations for the frequency of inspection based on measurements. Results offer implications for adequacy of preventive and corrective maintenance performed in healthcare institutions. Based on collected data, the first digital electronical database of anesthesia machines and defibrillators used in healthcare institutions in Bosnia and Herzegovina is created. This database is a useful tool for tracking each device's performance over time.

  4. Hvor er den automatiske eksterne defibrillator? Udvikling og uddannelse

    DEFF Research Database (Denmark)

    Løfgren, Bo; Grove, Erik; Krarup, Niels Henrik

    2009-01-01

    The International Liaison Committee on Resuscitation has presented a universal sign to indicate the presence of automated external defibrillators (AED). To disseminate the knowledge of this important signage, a review in a Danish context is presented. It is essential that the public in general...

  5. Worldwide experience with a totally subcutaneous implantable defibrillator

    DEFF Research Database (Denmark)

    Lambiase, Pier D; Barr, Craig; Theuns, Dominic A M J

    2014-01-01

    AIMS: The totally subcutaneous implantable-defibrillator (S-ICD) is a new alternative to the conventional transvenous ICD system to minimize intravascular lead complications. There are limited data describing the long-term performance of the S-ICD. This paper presents the first large internationa...

  6. Pacemakers and Implantable Defibrillators: MedlinePlus Health Topic

    Science.gov (United States)

    ... ClinicalTrials.gov: Pacemaker, Artificial (National Institutes of Health) Journal Articles References and abstracts from MEDLINE/PubMed (National ... Leadless Cardiac Pacemakers: The Next Evolution in Pacemaker Technology. ... on Pacemakers and Implantable Defibrillators is the National Heart, Lung, and Blood Institute Other Languages Find health information in languages other than English on Pacemakers and ...

  7. Estudo clínico de um sistema cardioversor-desfibrilador implantável que apresenta limiares de desfibrilação baixos usando eletrodos de estrutura fractal Clinical studies of an implantable cardioversor - defibrillators system providing low defibrillation thresholds as well as high signal amplitudes due to fractal coated electrodes

    Directory of Open Access Journals (Sweden)

    Fernando A. LUCCHESE

    1999-01-01

    Full Text Available Em função do contínuo desenvolvimento tecnológico, a geração atual de cardioversores-desfibriladores implantáveis (CDI garante um alto grau de segurança e eficiência na detecção e reversão de taquiarritmias ventriculares. O presente trabalho sumariza os resultados clínicos obtidos com 1058 CDI de câmara única (Phylax 6, Phylax XM, Biotronik utilizando eletrodo único e tecnologia de carcaça ativa, SPS e Kainox RV (com uma mola intracavitária de choque, SL-ICD e Kainox SL (com duas molas intracavitárias de choque, Biotronik. Na quase totalidade dos pacientes, com exceção de 3 (> 99%, foram obtidos limiares de desfibrilação com baixa energia usando apenas um eletrodo transvenoso. Isto tem permitido substituir o teste de limiar de desfibrilação usual por um teste simples durante o implante, afim de minimizar os riscos associados com repetidas induções de fibrilação e conseqüente extensão do período de anestesia.Due to continuously improved technologies, the present generation of implantable cardioverter-defibrillators (ICD guarantees a high degree of safety and efficacy for detecting and terminating ventricular tachyarrhythmias. This paper summarizes the clinical results obtained with 1058 single-chamber ICD (Phylax 6, Phylax XM, Biotronik employing single-lead and active housing technology (SPS and Kainox RV (single coil, SL-ICD and Kainox SL (double coil, Biotronik. In all but 3 patients (> 99%, reliable low-energy defibrillation was achieved using transvenous leads only. This has led to the trend to replace DFT testing by a short function test during implantation in order to minimize the risks associated with repeated induction of fibrillation and extended anesthesia.

  8. Exact Cross-Validation for kNN and applications to passive and active learning in classification

    OpenAIRE

    Célisse, Alain; Mary-Huard, Tristan

    2011-01-01

    In the binary classification framework, a closed form expression of the cross-validation Leave-p-Out (LpO) risk estimator for the k Nearest Neighbor algorithm (kNN) is derived. It is first used to study the LpO risk minimization strategy for choosing k in the passive learning setting. The impact of p on the choice of k and the LpO estimation of the risk are inferred. In the active learning setting, a procedure is proposed that selects new examples using a LpO committee of kNN classifiers. The...

  9. Bystander defibrillation for out-of-hospital cardiac arrest in Public vs Residential Locations

    DEFF Research Database (Denmark)

    Hansen, Steen Møller; Hansen, Carolina Malta; Folke, Fredrik

    2017-01-01

    Importance: Bystander-delivered defibrillation (hereinafter referred to as bystander defibrillation) of patients with out-of-hospital cardiac arrests (OHCAs) remains limited despite the widespread dissemination of automated external defibrillators (AEDs). Objective: To examine calendar changes...... in bystander defibrillation and subsequent survival according to a public or a residential location of the cardiac arrest after nationwide initiatives in Denmark to facilitate bystander-mediated resuscitative efforts, including bystander defibrillation. Design, Setting, and Participants: This nationwide study......, 2016. Exposures: Nationwide initiatives to facilitate bystander resuscitative efforts, including bystander defibrillation, consisted of resuscitation training of Danish citizens, dissemination of on-site AEDs, foundation of an AED registry linked to emergency medical dispatch centers, and dispatcher...

  10. Factors associated with delayed defibrillation in cardiopulmonary resuscitation: A prospective simulation study.

    Directory of Open Access Journals (Sweden)

    Christoph Castan

    Full Text Available Early defibrillation is an important factor of survival in cardiac arrest. However, novice resuscitators often struggle with cardiac arrest patients. We investigated factors leading to delayed defibrillation performed by final-year medical students within a simulated bystander cardiac arrest situation.Final-year medical students received a refresher lecture and basic life support training before being confronted with a simulated cardiac arrest situation in a simulation ambulance. The scenario was analyzed for factors leading to delayed defibrillation. We compared the time intervals the participants needed for various measures with a benchmark set by experienced resuscitators. After training, the participants were interviewed regarding challenges and thoughts during the scenario.The median time needed for defibrillation was 158 s (n = 49, interquartile range: 107-270 s, more than six-fold of the benchmark time. The major part of total defibrillation time (49%; median, n = 49 was between onset of ventricular fibrillation and beginning to prepare the defibrillator, more specifically the time between end of preparation of the defibrillator and actual delivery of the shock, with a mean proportion of 26% (n = 49, SD = 17% of the overall time needed for defibrillation (maximum 67%. Self-reported reasons for this delay included uncertainty about the next step to take, as reported by 73% of the participants. A total of 35% were unsure about which algorithm to follow. Diagnosing the patient was subjectively difficult for 35% of the participants. Overall, 53% of the participants felt generally confused.Our study shows that novice resuscitators rarely achieve guideline-recommended defibrillation times. The most relative delays were observed when participants had to choose what to do next or which algorithm to follow, and thus i.e. performed extensive airway management before a life-saving defibrillation. Our data provides a first insight in the process of

  11. Live defibrillation in simulation-based medical education--a survey of simulation center practices and attitudes.

    Science.gov (United States)

    Turban, Joseph W; Peters, Deborah P; Berg, Benjamin W

    2010-02-01

    Resuscitation from cardiac arrhythmia, requiring cardioversion/defibrillation is a common simulation training scenario. Use of live defibrillation enhances simulation fidelity but is not without risk. This survey was conducted to describe the prevalence of live defibrillation use during training scenarios in healthcare simulation centers, and when used, if safety training was required before using live defibrillation. A convenience sample of attendees at the 7th annual International Meeting on Simulation in Healthcare (January 2007) was surveyed using a closed-ended 23-item survey instrument. Survey domains included responder and simulation center demographics, simulation center defibrillation safety policies, and attitudes toward defibrillation practices in simulation training environments. Fifty-seven individuals representing 39 simulation centers returned surveys, 29 of which were in the United States. Live defibrillation was used in 35 of the 39 centers (90%). A defibrillation safety training policy was in effect at 14 of 39 centers (36%). Formal training before using live defibrillation was considered necessary by 48 of 55 responders (87%). Forty-eight of 54 responders (89%) strongly agreed or agreed with the statement, "I feel using live defibrillation plays an important role in simulation-based education." Although most responders consider use of live defibrillation important and believe formal defibrillator safety training should be conducted before use, only about one third of the centers had a training policy in effect. It remains to be determined whether safety training before the use of live defibrillation during simulation-based education increases user safety.

  12. The Effects of Normothermic and Hypothermic Cardiopulmonary Bypass Upon Defibrillation Energy Requirements and Transmyocardial Impedance

    National Research Council Canada - National Science Library

    Martin, David

    1993-01-01

    .... To evaluate these questions we studied the effect of controlled hypothermia upon defibrillation energy requirements and transcardiac impedance in a canine model of cardiopulmonary bypass in which 26...

  13. Heart rate variability density analysis (Dyx) for identification of appropriate implantable cardioverter defibrillator recipients among elderly patients with acute myocardial infarction and left ventricular systolic dysfunction

    DEFF Research Database (Denmark)

    Jørgensen, Rikke Mørch; Levitan, Jacob; Halevi, Zohar

    2015-01-01

    AIMS: Dyx is a new heart rate variability (HRV) density analysis specifically designed to identify patients at high risk for malignant ventricular arrhythmias. The aim of this study was to test if Dyx can improve risk stratification for malignant ventricular tachyarrhythmias and to test if the pr......AIMS: Dyx is a new heart rate variability (HRV) density analysis specifically designed to identify patients at high risk for malignant ventricular arrhythmias. The aim of this study was to test if Dyx can improve risk stratification for malignant ventricular tachyarrhythmias and to test...

  14. Physical activity in primary versus secondary prevention indication implantable cardioverter defibrillator recipients 6-12 months after implantation - a cross-sectional study with register follow up

    DEFF Research Database (Denmark)

    Berg, S. K.; Thygesen, L. C.; Svendsen, J. H.

    2015-01-01

    OBJECTIVE: To describe (i) physical activity status among ICD patients according to the indication for ICD implant compared to international guidelines and compared to a matched normal population in order to detect potentials for improved physical outcomes, (ii) patients' beliefs regarding...... and participation in physical exercise by ICD indication, (iii) factors predicting low physical activity, and (iv) physical activity as a predictor of mortality. DESIGN: National survey with register follow-up. Comparisons were made to a matched healthy reference population and patients were followed in registers...... MEASURES: Questions regarding physical activity and the IPAQ questionnaire were used to assess physical activity. RESULTS: The response rate was 71.7%. Mean age 65.5 years with 82% males. 37% participated in a rehabilitation programme. 21 % were sedentary compared to 8 % in the reference population (p

  15. Prophylactic catheter ablation of ventricular tachycardia before cardioverter-defibrillator implantation in patients with non-ischemic cardiomyopathy: Clinical outcomes after a single endocardial ablation

    Directory of Open Access Journals (Sweden)

    Atsushi Suzuki, MD

    2015-06-01

    Conclusion: Single endocardial PCA can decrease ES occurrence in NICM patients. However, high rates of VT recurrence and low success rates are issues to be resolved; therefore, the efficacy of single endocardial PCA is currently limited.

  16. The CopenHeartSF trial—comprehensive sexual rehabilitation programme for male patients with implantable cardioverter defibrillator or ischaemic heart disease and impaired sexual function

    DEFF Research Database (Denmark)

    Johansen, Pernille Palm; Zwisler, Ann-Dorthe; Svendsen, Jesper Hastrup

    2013-01-01

    Sexuality is an important part of people's physical and mental health. Patients with heart disease often suffer from sexual dysfunction. Sexual dysfunction has a negative impact on quality of life and well-being in persons with heart disease, and sexual dysfunction is associated with anxiety...... and depression. Treatment and care possibilities seem to be lacking. Studies indicate that non-pharmacological interventions such as exercise training and psychoeducation possess the potential of reducing sexual dysfunction in patients with heart disease. The CopenHeartSF trial will investigate the effect...

  17. Frequency of "Pocket" Hematoma in Patients Receiving Vitamin K Antagonist and Antiplatelet Therapy at the Time of Pacemaker or Cardioverter Defibrillator Implantation (from the POCKET Study).

    Science.gov (United States)

    Malagù, Michele; Trevisan, Filippo; Scalone, Antonella; Marcantoni, Lina; Sammarco, Giuseppe; Bertini, Matteo

    2017-04-01

    In patients undergoing cardiac device implantation, anticoagulant and antiplatelet therapy are associated with an increased risk of pocket hematoma. In case of vitamin K antagonist therapy, a strategy of continued warfarin with no heparin bridge showed a reduction of pocket hematoma. Evidence regarding antiplatelet therapy management is limited. This is a single-center observational study which reflects our systematic approach to the problem. In 2012, we proposed an improved management protocol for anticoagulant and antiplatelet therapy (no-bridge protocol) based on individual thromboembolic risk stratification, noninterruption of oral anticoagulation, no bridge with heparin and elastic adherence compression bandage. The primary end point was the incidence of clinically significant pocket hematoma in the first 30 days after implantation. A total of 1,035 patients were enrolled, of whom 522 received the standard management and 513 the new protocol. The primary end point occurred in 34 patients of the standard management group and 8 patients of the no-bridge protocol group (6.5% vs 1.6%, p hematoma (relative risk [RR] 3.48, 95% confidence interval [CI] 1.55 to 7.83 and RR 2.43, 95% CI 1.25 to 4.76, respectively), whereas the no-bridge protocol was associated with a reduction of pocket hematoma (RR 0.33, 95% CI 0.14 to 0.76). New anticoagulant and antiplatelet therapy management protocol was associated with a reduced incidence of clinically significant pocket hematomas, thromboembolic events, pocket infections, and lead dislodgements. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Estimation of current density distribution under electrodes for external defibrillation

    Directory of Open Access Journals (Sweden)

    Papazov Sava P

    2002-12-01

    Full Text Available Abstract Background Transthoracic defibrillation is the most common life-saving technique for the restoration of the heart rhythm of cardiac arrest victims. The procedure requires adequate application of large electrodes on the patient chest, to ensure low-resistance electrical contact. The current density distribution under the electrodes is non-uniform, leading to muscle contraction and pain, or risks of burning. The recent introduction of automatic external defibrillators and even wearable defibrillators, presents new demanding requirements for the structure of electrodes. Method and Results Using the pseudo-elliptic differential equation of Laplace type with appropriate boundary conditions and applying finite element method modeling, electrodes of various shapes and structure were studied. The non-uniformity of the current density distribution was shown to be moderately improved by adding a low resistivity layer between the metal and tissue and by a ring around the electrode perimeter. The inclusion of openings in long-term wearable electrodes additionally disturbs the current density profile. However, a number of small-size perforations may result in acceptable current density distribution. Conclusion The current density distribution non-uniformity of circular electrodes is about 30% less than that of square-shaped electrodes. The use of an interface layer of intermediate resistivity, comparable to that of the underlying tissues, and a high-resistivity perimeter ring, can further improve the distribution. The inclusion of skin aeration openings disturbs the current paths, but an appropriate selection of number and size provides a reasonable compromise.

  19. An MRI-Conditional External Cardiac Defibrillator for Resuscitation Within the MRI Scanner Bore

    Science.gov (United States)

    Schmidt, Ehud J.; Watkins, Ronald D.; Zviman, Menekhem M.; Guttman, Michael A.; Wang, Wei; Halperin, Henry A.

    2016-01-01

    Background Subjects undergoing cardiac arrest within an MRI scanner are currently removed from the bore and then from the MRI suite, prior to delivery of CPR and defibrillation, potentially increasing risk of mortality. This precludes many higher-risk (acute-ischemic, acute-stroke) patients from undergoing MRI imaging and MRI-guided intervention. An MRI-conditional cardiac defibrillator should enable scanning with defibrillation pads attached and the generator ON, enabling application of defibrillation within the MRI seconds after a cardiac event. An MRI-conditional external defibrillator may improve patient acceptance for MRI procedures. Methods and Results A commercial external defibrillator was rendered 1.5 Tesla MRI-conditional by addition of novel Radio-Frequency (RF) filters between the generator and commercial disposable surface-pads. The RF filters reduced emission into the MRI scanner, and prevented cable/surface-pad heating during imaging, while preserving all the defibrillator’s monitoring and delivery functions. Human volunteers were imaged using high Specific-Absorption-Rate sequences to validate MRI image quality (IQ) and lack of heating. Swine were electrically fibrillated (N=4) and thereafter defibrillated both outside and inside the MRI bore. MRI IQ was reduced by 0.8 or 1.6 dB, with the generator in monitoring mode and operating on battery or AC power, respectively. Commercial surface-pads did not create artifacts deeper than 6mm below the skin surface. RF heating was within FDA guidelines. Defibrillation was completely successful inside and outside the MRI bore. Conclusions A prototype MRI-conditional defibrillation system successfully defibrillated in the MRI without degrading image quality, or increasing the time needed for defibrillation. It can increase patient acceptance for MRI procedures. PMID:27729363

  20. Law Enforcement Agency Defibrillation (LEA-D): proceedings of the National Center for Early Defibrillation Police AED Issues Forum.

    Science.gov (United States)

    Mosesso, Vincent N; Newman, Mary M; Ornato, Joseph P; Paris, Paul M; Andersen, Leon; Brinsfield, Kathryn; Dunnavant, Gregory R; Frederick, Jay; Groh, William J; Johnston, Steven; Lerner, E Brooke; Murphy, George P; Myerburg, Robert J; Rosenberg, Donald G; Savino, Mitchell; Sayre, Michael R; Sciammarella, Joseph; Schoen, Valerie; Vargo, Philip; van Alem, Anouk; White, Roger D

    2002-01-01

    Why does LEA-D intervention seem to work in some systems but not others? Panelists agreed that some factors that delay rapid access to treatment, such as long travel distances in rural areas, may represent insurmountable barriers. Other factors, however, may be addressed more readily. These include: absence of a medical response culture, discomfort with the role of medical intervention, insecurity with the use of medical devices, a lack of proactive medical direction, infrequent refresher training, and dependence on EMS intervention. Panelists agreed that successful LEA-D programs possess ten key attributes (Table 6). In the end, the goal remains "early" defibrillation, not "police" defibrillation. It does not matter whether the rescuer wears a blue uniform--or any uniform, for that matter--so long as the defibrillator reaches the victim quickly. If LEA personnel routinely arrive at medical emergencies after other emergency responders or after 8 minutes have elapsed from the time of collapse, an LEA-D program will be unlikely to provide added value. Similarly, if police frequently arrive first, but the department is unwilling or unable to cultivate the attributes of successful LEA-D programs, efforts to improve survival may not be realized. In most communities, however, LEA-D programs have tremendous lifesaving potential and are well worth the investment of time and resources. Law enforcement agencies considering adoption of AED programs should review the frequency with which police arrive first at medical emergencies and LEA response intervals to determine whether AED programs might help improve survival in their communities. It is time for law enforcement agency defibrillation to become the rule, not the exception.

  1. The role of conductivity discontinuities in design of cardiac defibrillation

    Science.gov (United States)

    Lim, Hyunkyung; Cun, Wenjing; Wang, Yue; Gray, Richard A.; Glimm, James

    2018-01-01

    Fibrillation is an erratic electrical state of the heart, of rapid twitching rather than organized contractions. Ventricular fibrillation is fatal if not treated promptly. The standard treatment, defibrillation, is a strong electrical shock to reinitialize the electrical dynamics and allow a normal heart beat. Both the normal and the fibrillatory electrical dynamics of the heart are organized into moving wave fronts of changing electrical signals, especially in the transmembrane voltage, which is the potential difference between the cardiac cellular interior and the intracellular region of the heart. In a normal heart beat, the wave front motion is from bottom to top and is accompanied by the release of Ca ions to induce contractions and pump the blood. In a fibrillatory state, these wave fronts are organized into rotating scroll waves, with a centerline known as a filament. Treatment requires altering the electrical state of the heart through an externally applied electrical shock, in a manner that precludes the existence of the filaments and scroll waves. Detailed mechanisms for the success of this treatment are partially understood, and involve local shock-induced changes in the transmembrane potential, known as virtual electrode alterations. These transmembrane alterations are located at boundaries of the cardiac tissue, including blood vessels and the heart chamber wall, where discontinuities in electrical conductivity occur. The primary focus of this paper is the defibrillation shock and the subsequent electrical phenomena it induces. Six partially overlapping causal factors for defibrillation success are identified from the literature. We present evidence in favor of five of these and against one of them. A major conclusion is that a dynamically growing wave front starting at the heart surface appears to play a primary role during defibrillation by critically reducing the volume available to sustain the dynamic motion of scroll waves; in contrast, virtual

  2. Defibrillation probability and impedance change between shocks during resuscitation from out-of-hospital cardiac arrest

    NARCIS (Netherlands)

    Walker, Robert G.; Koster, Rudolph W.; Sun, Charles; Moffat, George; Barger, Joseph; Dodson, Pamela P.; Chapman, Fred W.

    2009-01-01

    Objective: Technical data now gathered by automated external defibrillators (AEDs) allows closer evaluation of the behavior of defibrillation shocks administered during out-of-hospital cardiac arrest. We analyzed technical data from a large case series to evaluate the change in transthoracic

  3. Long Detection Programming in Single-Chamber Defibrillators Reduces Unnecessary Therapies and Mortality: The ADVANCE III Trial.

    Science.gov (United States)

    Gasparini, Maurizio; Lunati, Maurizio G; Proclemer, Alessandro; Arenal, Angel; Kloppe, Axel; Martínez Ferrer, Josè B; Hersi, Ahmad S; Gulaj, Marcin; Wijffels, Maurits C E; Santi, Elisabetta; Manotta, Laura; Varma, Niraj

    2017-11-01

    This study sought to evaluate the effects of programming a long detection in single-chamber (VVI) implantable cardioverter-defibrillators (ICDs) in the multicenter prospective ADVANCE III (Avoid DeliVering TherApies for Non-sustained Arrhythmias in ICD PatiEnts III) trial. Programming strategies may reduce unnecessary ICD shocks and their adverse effects but to date have been described only for dual-chamber ICDs. A total of 545 subjects (85% male; atrial fibrillation 25%, left ventricular ejection fraction 31%, ischemic etiology 68%, secondary prevention indications 32%) receiving a VVI ICD were randomized to long detection (30 of 40 intervals) or standard programming (18 of 24 intervals) based on device type, atrial fibrillation history, and indication. In both arms, antitachycardia pacing (ATP) therapy during charging was programmed for episodes with cycle length 320 to 200 ms and shock only for cycle length functions enabled. Therapies delivered were compared using a negative binomial regression model. A total of 267 patients were randomized to long detection and 278 to the control group. Median follow-up was 12 months. One hundred twelve therapies (shocks and ATP) occurred in the long detection arm versus 257 in the control arm, for a 48% reduction with 30 of 40 intervals (95% confidence interval [CI]: 0.36 to 0.76; p = 0.002). In the long detection arm, overall shocks were reduced by 40% compared to the control arm (48 vs. 24; 95% CI: 0.38 to 0.94; p = 0.026) and appropriate shocks by 51% (34 vs. 74; 95% CI: 0.26 to 0.94; p = 0.033). Syncopal events did not differ between arms, but survival improved in the long detection arm. Among patients implanted with a VVI ICD, programming with the long detection interval significantly reduced appropriate therapies, shocks, and all-cause mortality. (Avoid DeliVering TherApies for Non-sustained Arrhythmias in ICD PatiEnts III [ADVANCEIII]; NCT00617175). Copyright © 2017 The Authors. Published by Elsevier Inc. All

  4. Bystander Defibrillation for Out-of-Hospital Cardiac Arrest in Public vs Residential Locations.

    Science.gov (United States)

    Hansen, Steen Møller; Hansen, Carolina Malta; Folke, Fredrik; Rajan, Shahzleen; Kragholm, Kristian; Ejlskov, Linda; Gislason, Gunnar; Køber, Lars; Gerds, Thomas A; Hjortshøj, Søren; Lippert, Freddy; Torp-Pedersen, Christian; Wissenberg, Mads

    2017-05-01

    Bystander-delivered defibrillation (hereinafter referred to as bystander defibrillation) of patients with out-of-hospital cardiac arrests (OHCAs) remains limited despite the widespread dissemination of automated external defibrillators (AEDs). To examine calendar changes in bystander defibrillation and subsequent survival according to a public or a residential location of the cardiac arrest after nationwide initiatives in Denmark to facilitate bystander-mediated resuscitative efforts, including bystander defibrillation. This nationwide study identified 18 688 patients in Denmark with first-time OHCA from June 1, 2001, to December 31, 2012, using the Danish Cardiac Arrest Registry. Patients had a presumed cardiac cause of arrest that was not witnessed by emergency medical services personnel. Data were analyzed from April 1, 2015, to December 10, 2016. Nationwide initiatives to facilitate bystander resuscitative efforts, including bystander defibrillation, consisted of resuscitation training of Danish citizens, dissemination of on-site AEDs, foundation of an AED registry linked to emergency medical dispatch centers, and dispatcher-assisted guidance of bystander resuscitation efforts. The proportion of patients who received bystander defibrillation according to the location of the cardiac arrest and their subsequent 30-day survival. Of the 18 688 patients with OHCAs (67.8% men and 32.2% women; median [interquartile range] age, 72 [62-80] years), 4783 (25.6%) had a cardiac arrest in a public location and 13 905 (74.4%) in a residential location. The number of registered AEDs increased from 141 in 2007 to 7800 in 2012. The distribution of AED location was consistently skewed in favor of public locations. Bystander defibrillation increased in public locations from 3 of 245 (1.2%; 95% CI, 0.4%-3.5%) in 2001 to 78 of 510 (15.3%; 95% CI, 12.4%-18.7%) in 2012 (P bystander defibrillation increased in public locations from 8.3% (95% CI, 1.5%-35.4%) in 2001/2002 to 57

  5. A Procedure for Identification of Appropriate State Space and ARIMA Models Based on Time-Series Cross-Validation

    Directory of Open Access Journals (Sweden)

    Patrícia Ramos

    2016-11-01

    Full Text Available In this work, a cross-validation procedure is used to identify an appropriate Autoregressive Integrated Moving Average model and an appropriate state space model for a time series. A minimum size for the training set is specified. The procedure is based on one-step forecasts and uses different training sets, each containing one more observation than the previous one. All possible state space models and all ARIMA models where the orders are allowed to range reasonably are fitted considering raw data and log-transformed data with regular differencing (up to second order differences and, if the time series is seasonal, seasonal differencing (up to first order differences. The value of root mean squared error for each model is calculated averaging the one-step forecasts obtained. The model which has the lowest root mean squared error value and passes the Ljung–Box test using all of the available data with a reasonable significance level is selected among all the ARIMA and state space models considered. The procedure is exemplified in this paper with a case study of retail sales of different categories of women’s footwear from a Portuguese retailer, and its accuracy is compared with three reliable forecasting approaches. The results show that our procedure consistently forecasts more accurately than the other approaches and the improvements in the accuracy are significant.

  6. Latent structure and reliability analysis of the measure of body apperception: cross-validation for head and neck cancer patients.

    Science.gov (United States)

    Jean-Pierre, Pascal; Fundakowski, Christopher; Perez, Enrique; Jean-Pierre, Shadae E; Jean-Pierre, Ashley R; Melillo, Angelica B; Libby, Rachel; Sargi, Zoukaa

    2013-02-01

    Cancer and its treatments are associated with psychological distress that can negatively impact self-perception, psychosocial functioning, and quality of life. Patients with head and neck cancers (HNC) are particularly susceptible to psychological distress. This study involved a cross-validation of the Measure of Body Apperception (MBA) for HNC patients. One hundred and twenty-two English-fluent HNC patients between 20 and 88 years of age completed the MBA on a Likert scale ranging from "1 = disagree" to "4 = agree." We assessed the latent structure and internal consistency reliability of the MBA using Principal Components Analysis (PCA) and Cronbach's coefficient alpha (α), respectively. We determined convergent and divergent validities of the MBA using correlations with the Hospital Anxiety and Depression Scale (HADS), observer disfigurement rating, and patients' clinical and demographic variables. The PCA revealed a coherent set of items that explained 38 % of the variance. The Kaiser-Meyer-Olkin measure of sampling adequacy was 0.73 and the Bartlett's test of sphericity was statistically significant (χ (2) (28) = 253.64; p 0.05). The MBA is a valid and reliable screening measure of body apperception for HNC patients.

  7. A cross-validation Delphi method approach to the diagnosis and treatment of personality disorders in older adults.

    Science.gov (United States)

    Rosowsky, Erlene; Young, Alexander S; Malloy, Mary C; van Alphen, S P J; Ellison, James M

    2018-03-01

    The Delphi method is a consensus-building technique using expert opinion to formulate a shared framework for understanding a topic with limited empirical support. This cross-validation study replicates one completed in the Netherlands and Belgium, and explores US experts' views on the diagnosis and treatment of older adults with personality disorders (PD). Twenty-one geriatric PD experts participated in a Delphi survey addressing diagnosis and treatment of older adults with PD. The European survey was translated and administered electronically. First-round consensus was reached for 16 out of 18 items relevant to diagnosis and specific mental health programs for personality disorders in older adults. Experts agreed on the usefulness of establishing criteria for specific types of treatments. The majority of psychologists did not initially agree on the usefulness of pharmacotherapy. Expert consensus was reached following two subsequent rounds after clarification addressing medication use. Study results suggest consensus among regarding psychosocial treatments. Limited acceptance amongst US psychologists about the suitability of pharmacotherapy for late-life PDs contrasted with the views expressed by experts surveyed in Netherlands and Belgium studies.

  8. Cross-validation of generalised body composition equations with diverse young men and women: the Training Intervention and Genetics of Exercise Response (TIGER) Study

    Science.gov (United States)

    Generalised skinfold equations developed in the 1970s are commonly used to estimate laboratory-measured percentage fat (BF%). The equations were developed on predominately white individuals using Siri's two-component percentage fat equation (BF%-GEN). We cross-validated the Jackson-Pollock (JP) gene...

  9. Cross-Validation of a Recently Published Equation Predicting Energy Expenditure to Run or Walk a Mile in Normal-Weight and Overweight Adults

    Science.gov (United States)

    Morris, Cody E.; Owens, Scott G.; Waddell, Dwight E.; Bass, Martha A.; Bentley, John P.; Loftin, Mark

    2014-01-01

    An equation published by Loftin, Waddell, Robinson, and Owens (2010) was cross-validated using ten normal-weight walkers, ten overweight walkers, and ten distance runners. Energy expenditure was measured at preferred walking (normal-weight walker and overweight walkers) or running pace (distance runners) for 5 min and corrected to a mile. Energy…

  10. Rasch Validation and Cross-validation of the Health of Nation Outcome Scales (HoNOS) for Monitoring of Psychiatric Disability in Traumatized Refugees in Western Psychiatric Care

    DEFF Research Database (Denmark)

    Palic, Sabina; Kappel, Michelle Lind; Makransky, Guido

    2016-01-01

    group. A revised 10-item HoNOS fit the Rasch model at pre-treatment, and also showed excellent fit within the cross-validation data. Culture, gender, and need for translation did not exert serious bias on the measure’s performance. The results establish good monitoring properties of the 10-item Ho...

  11. Automated external defibrillators in the Australian fitness industry.

    Science.gov (United States)

    Norton, Kevin I; Norton, Lynda H

    2008-04-01

    Sudden cardiac arrest (SCA) occurs in many thousands of Australians each year. Scientific evidence shows an increased survival rate for individuals who receive electrical defibrillation in the first few minutes after SCA. In the last decade automated (rhythm-detecting) external defibrillators (AEDs) have become available that are portable and affordable. Although still relatively rare, there is still the potential that SCA may occur when a person undertakes physical activity. Consequently, health/fitness centres are increasingly recognised as higher risk sites that may benefit from placement of AEDs. There are no laws in Australia requiring health/fitness centres to install AEDs. However, several international and professional organisations have "strongly encouraged" larger centres to install AEDs. Guidelines and algorithms are presented to help estimate the risk of SCA in fitness centres. Fitness centre placement is particularly important if the clientele is older or has a 'high-risk' profile, for example, clients with cardiovascular, respiratory or metabolic disease. International negligence case law and duty of care principles suggests the standard of care required in health/fitness centres may be increasing. Therefore, it may be prudent to install AEDs in larger centres and those in which higher risk groups are physically active.

  12. Dual- vs. single-chamber defibrillators for primary prevention of sudden cardiac death: long-term follow-up of the Défibrillateur Automatique Implantable-Prévention Primaire registry.

    Science.gov (United States)

    Defaye, Pascal; Boveda, Serge; Klug, Didier; Beganton, Frankie; Piot, Olivier; Narayanan, Kumar; Périer, Marie-Cécile; Gras, Daniel; Fauchier, Laurent; Bordachar, Pierre; Algalarrondo, Vincent; Babuty, Dominique; Deharo, Jean-Claude; Leclercq, Christophe; Marijon, Eloi; Sadoul, Nicolas

    2017-09-01

    Implantable cardioverter defibrillators (ICDs) are an effective primary prevention of sudden cardiac death. We examined whether dual-chamber (DC) ICDs confer a greater benefit than single-chamber (SC) ICDs, and compared the long-term outcomes of recipients of each type of device implanted for primary prevention. Between 2002 and 2012, the DAI-PP registry consecutively enrolled 1258 SC- and 1280 DC-ICD recipients at 12 French medical centres. The devices were interrogated at 4- to 6-month intervals during outpatient visits, with a focus on the therapies delivered. The study endpoints were incidence of appropriate therapies, ICD-related morbidity, and deaths from all and from specific causes. The mean age of the SC- and DC-ICD recipients was 59 ± 12 and 62 ± 11 years, respectively (PDC- vs. 8.8% in the SC-ICD groups (P= 0.008). Over a mean follow-up of 3.1 ± 2.2 years, pulse generators were replaced in 21.9% of the DC- vs. 13.6% of the SC-ICD group (PDC-ICDs were associated with higher rates of peri-implant complications and generator replacements, whereas the survival and rates of inappropriate shocks were similar in both groups. NCT#01992458. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions please email: journals.permissions@oup.com.

  13. Cross-validation of the Student Perceptions of Team-Based Learning Scale in the United States

    Directory of Open Access Journals (Sweden)

    Donald H. Lein

    2017-06-01

    Full Text Available Purpose The purpose of this study was to cross-validate the factor structure of the previously developed Student Perceptions of Team-Based Learning (TBL Scale among students in an entry-level doctor of physical therapy (DPT program in the United States. Methods Toward the end of the semester in 2 patient/client management courses taught using TBL, 115 DPT students completed the Student Perceptions of TBL Scale, with a response rate of 87%. Principal component analysis (PCA and confirmatory factor analysis (CFA were conducted to replicate and confirm the underlying factor structure of the scale. Results Based on the PCA for the validation sample, the original 2-factor structure (preference for TBL and preference for teamwork of the Student Perceptions of TBL Scale was replicated. The overall goodness-of-fit indices from the CFA suggested that the original 2-factor structure for the 15 items of the scale demonstrated a good model fit (comparative fit index, 0.95; non-normed fit index/Tucker-Lewis index, 0.93; root mean square error of approximation, 0.06; and standardized root mean square residual, 0.07. The 2 factors demonstrated high internal consistency (alpha= 0.83 and 0.88, respectively. DPT students taught using TBL viewed the factor of preference for teamwork more favorably than preference for TBL. Conclusion Our findings provide evidence supporting the replicability of the internal structure of the Student Perceptions of TBL Scale when assessing perceptions of TBL among DPT students in patient/client management courses.

  14. Effects of postshock atrial pacing on atrial defibrillation outcome in the isolated sheep heart

    NARCIS (Netherlands)

    Skanes, A. C.; Gray, R. A.; Zuur, C. L.; Jalife, J.

    1998-01-01

    BACKGROUND: Failed atrial defibrillation shocks are associated with organization of postshock activity and a substantial postshock electrical quiescence. We investigated the ability of a train of pacing stimuli to capture or locally entrain atrial myocardium during the quiescent period after

  15. Use of automated external defibrillators in a Brazilian airline. A 1-year experience

    Directory of Open Access Journals (Sweden)

    Alves Paulo Magalhães

    2001-01-01

    Full Text Available After the incorporation of automated external defibrilators by other airlines and the support of the Brazilian Society of cardiology, Varig Airlines Began the onboard defibrilation program with the initial purpose of equiping wide-body aircrafts frequently used in international flights and that airplanes use in the Rio - São Paulo route. With all fight attendants trained, the automated. External defibrilation devides were incorporated to 34 airplanes of a total pleet of 80 aircrats. The devices were intalled in the bagage compartments secured with velero straps and 2 pairs of electrods, one or which pre-conected to the device to minimize application time. Later, a portable monitor was addres to the ressocitation kit in the long flights. The expansion of the knowledge of the basic life support fundamentors and the correted implantation of the survival chain and of the automated external defibrilators will increase the extense of recovery of cardiorespiratory arrest victins in aircrafts.

  16. Automated external defibrillators in National Collegiate Athletic Association Division I Athletics.

    Science.gov (United States)

    Coris, Eric E; Sahebzamani, Frances; Walz, Steve; Ramirez, Arnold M

    2004-01-01

    Sudden cardiac death is the leading cause of death in athletes. Evidence on current sudden cardiac death prevention through preparticipation history, physicals, and noninvasive cardiovascular diagnostics has demonstrated a low sensitivity for detection of athletes at high risk of sudden cardiac death. Data are lacking on automated external defibrillator programs specifically initiated to respond to rare dysrhythmia in younger, relatively low-risk populations. Surveys were mailed to the head athletic trainers of all National Collegiate Athletic Association Division I athletics programs listed in the National Athletic Trainers' Association directory. In all, 303 surveys were mailed; 186 departments (61%) responded. Seventy-two percent (133) of responding National Collegiate Athletic Association Division I athletics programs have access to automated external defibrillator units; 54% (101) own their units. Proven medical benefit (55%), concern for liability (51%), and affordability (29%) ranked highest in frequency of reasons for automated external defibrillator purchase. Unit cost (odds ratio = 1.01; 95% confidence interval, 1.01-1.0), donated units (odds ratio = 1.92; confidence interval, 3.66-1.01), institution size (odds ratio =.0001; confidence interval, 1.3 E-4 to 2.2E-05), and proven medical benefit of automated external defibrillators (odds ratio = 24; confidence interval, 72-8.1) were the most significant predictors of departmental defibrillator ownership. Emergency medical service response time and sudden cardiac death event history were not significantly predictive of departmental defibrillator ownership. The majority of automated external defibrillator interventions occurred on nonathletes. Many athletics medicine programs are obtaining automated external defibrillators without apparent criteria for determination of need. Usage and maintenance policies vary widely among departments with unit ownership or access. Programs need to approach the issue of unit

  17. A qualitative study to identify barriers to deployment and student training in the use of automated external defibrillators in schools

    DEFF Research Database (Denmark)

    Zinckernagel, Line; Hansen, Carolina Malta; Rod, Morten Hulvej

    2017-01-01

    such as delayed access have been reported. The purpose of this study was to identify barriers to the implementation of defibrillator training of students and deployment of defibrillators in schools. Methods: A qualitative study based on semi-structured individual interviews and focus groups with a total of 25......Background: Student training in use of automated external defibrillators and deployment of such defibrillators in schools is recommended to increase survival after out-of-hospital cardiac arrest. Low implementation rates have been observed, and even at schools with a defibrillator, challenges...... to their perception of student training but not for their considerations on the relevance of their placement at schools. Conclusions: It is crucial for implementation of automated external defibrillators in schools to inform staff about how they work and are operated and that students are an appropriate target group...

  18. A qualitative study to identify barriers to deployment and student training in the use of automated external defibrillators in schools

    DEFF Research Database (Denmark)

    Zinckernagel, Line; Hansen, Carolina Malta; Rod, Morten Hulvej

    2017-01-01

    to their perception of student training but not for their considerations on the relevance of their placement at schools. Conclusions: It is crucial for implementation of automated external defibrillators in schools to inform staff about how they work and are operated and that students are an appropriate target group...... for defibrillator training. Furthermore, it is important to provide schools with a basis for decision making about when to install defibrillators, and to ensure that school staff and students are informed about their placement.......Background: Student training in use of automated external defibrillators and deployment of such defibrillators in schools is recommended to increase survival after out-of-hospital cardiac arrest. Low implementation rates have been observed, and even at schools with a defibrillator, challenges...

  19. Attitudes toward automated external defibrillator use in Japan.

    Science.gov (United States)

    Taniguchi, Takumi; Omi, Wataru; Inaba, Hideo

    2008-11-01

    The American Heart Association 2005 Guidelines recommend immediate defibrillation for ventricular fibrillation (VF) of short duration, such as witnessed sudden cardiac arrest. However, it is unclear if public-access automated external defibrillators (AEDs) would actually be used in Japan, because there have been few studies about public attitudes regarding AED use. Therefore, we examined Japanese attitudes toward AED use. Between February and March 2006, 3328 individuals, including high school students, teachers, emergency medical technicians (EMTs), medical nurses, and medical students, were asked about AED knowledge and their willingness to operate an AED. All EMTs, 86% of nurses, and 90% of medical students knew how to use AEDs, while only 15% of high school students and 44% of teachers had such knowledge. All EMTs, 78% of nurses, and 94% of medical students reported they would 'definitely' use the AED, but only 12% of high school students and 35% of teachers gave this reply. The reasons for unwillingness to operate AEDs among both laypeople and health care providers were poor of awareness of what AED is and/or how to use an AED. However, 83% of students and 81% of teachers with AED knowledge reported they would 'definitely' use the AED. Many non-medical people in Japan would be unwilling to operate an AED, because they do not know what AED is and/or how to use an AED. However, many would be willing to operate AEDs if they had better understanding of AEDs. Thus, it is necessary to improve public knowledge of AEDs and AED use.

  20. Optimizing a Drone Network to Deliver Automated External Defibrillators.

    Science.gov (United States)

    Boutilier, Justin J; Brooks, Steven C; Janmohamed, Alyf; Byers, Adam; Buick, Jason E; Zhan, Cathy; Schoellig, Angela P; Cheskes, Sheldon; Morrison, Laurie J; Chan, Timothy C Y

    2017-06-20

    Public access defibrillation programs can improve survival after out-of-hospital cardiac arrest, but automated external defibrillators (AEDs) are rarely available for bystander use at the scene. Drones are an emerging technology that can deliver an AED to the scene of an out-of-hospital cardiac arrest for bystander use. We hypothesize that a drone network designed with the aid of a mathematical model combining both optimization and queuing can reduce the time to AED arrival. We applied our model to 53 702 out-of-hospital cardiac arrests that occurred in the 8 regions of the Toronto Regional RescuNET between January 1, 2006, and December 31, 2014. Our primary analysis quantified the drone network size required to deliver an AED 1, 2, or 3 minutes faster than historical median 911 response times for each region independently. A secondary analysis quantified the reduction in drone resources required if RescuNET was treated as a large coordinated region. The region-specific analysis determined that 81 bases and 100 drones would be required to deliver an AED ahead of median 911 response times by 3 minutes. In the most urban region, the 90th percentile of the AED arrival time was reduced by 6 minutes and 43 seconds relative to historical 911 response times in the region. In the most rural region, the 90th percentile was reduced by 10 minutes and 34 seconds. A single coordinated drone network across all regions required 39.5% fewer bases and 30.0% fewer drones to achieve similar AED delivery times. An optimized drone network designed with the aid of a novel mathematical model can substantially reduce the AED delivery time to an out-of-hospital cardiac arrest event. © 2017 American Heart Association, Inc.

  1. A Study on Performance and Safety Tests of Defibrillator Equipment

    Directory of Open Access Journals (Sweden)

    Tavakoli Golpaygani A.

    2017-12-01

    Full Text Available Introduction: Nowadays, more than 10,000 different types of medical devices can be found in hospitals. This way, medical electrical equipment is being employed in a wide variety of fields in medical sciences with different physiological effects and measurements. Hospitals and medical centers must ensure that their critical medical devices are safe, accurate, reliable and operational at the required level of performance. Defibrillators are critical resuscitation devices. The use of reliable defibirillators has led to more effective treatments and improved patient safety through better control and management of complications during Cardiopulmonary Resuscitation (CPR. Materials and Methods: The metrological reliability of twenty frequent use, manual defibrillators in use ten hospitals (4 private and 6 public in one of the provinces of Iran according to international and national standards was evaluated. Results: Quantitative analysis of control and instrument accuracy showed the amount of the obtained results in many units are critical which had less value over the standard limitations especially in devices with poor battery. For the accuracy of delivered energy analysis, only twelve units delivered acceptable output values and the precision in the output energy measurements especialy in weak battry condition, after activation of discharge alarm, were low. Conclusion: Obtained results indicate a need for new and severe regulations on periodic performance verifications and medical equipment quality control program especially for high risk instruments. It is also necessary to provide training courses on the fundumentals of operation and performane parameters for medical staff in the field of meterology in medicine and how one can get good accuracy results especially in high risk medical devices.

  2. A Study on Performance and Safety Tests of Defibrillator Equipment.

    Science.gov (United States)

    Tavakoli Golpaygani, A; Movahedi, M M; Reza, M

    2017-12-01

    Nowadays, more than 10,000 different types of medical devices can be found in hospitals. This way, medical electrical equipment is being employed in a wide variety of fields in medical sciences with different physiological effects and measurements. Hospitals and medical centers must ensure that their critical medical devices are safe, accurate, reliable and operational at the required level of performance. Defibrillators are critical resuscitation devices. The use of reliable defibirillators has led to more effective treatments and improved patient safety through better control and management of complications during Cardiopulmonary Resuscitation (CPR). The metrological reliability of twenty frequent use, manual defibrillators in use ten hospitals (4 private and 6 public) in one of the provinces of Iran according to international and national standards was evaluated. Quantitative analysis of control and instrument accuracy showed the amount of the obtained results in many units are critical which had less value over the standard limitations especially in devices with poor battery. For the accuracy of delivered energy analysis, only twelve units delivered acceptable output values and the precision in the output energy measurements especialy in weak battry condition, after activation of discharge alarm, were low. Obtained results indicate a need for new and severe regulations on periodic performance verifications and medical equipment quality control program especially for high risk instruments. It is also necessary to provide training courses on the fundumentals of operation and performane parameters for medical staff in the field of meterology in medicine and how one can get good accuracy results especially in high risk medical devices.

  3. Hands-On Defibrillation Skills of Pediatric Acute Care Providers During a Simulated Ventricular Fibrillation Cardiac Arrest Scenario.

    Science.gov (United States)

    Bhalala, Utpal S; Balakumar, Niveditha; Zamora, Maria; Appachi, Elumalai

    2018-01-01

    Introduction: Timely defibrillation in ventricular fibrillation cardiac arrest (VFCA) is associated with good outcome. While defibrillation skills of pediatric providers have been reported to be poor, the factors related to poor hands-on defibrillation skills of pediatric providers are largely unknown. The aim of our study was to evaluate delay in individual steps of the defibrillation and human and non-human factors associated with poor hands-on defibrillation skills among pediatric acute care providers during a simulated VFCA scenario. Methods: We conducted a prospective observational study of video evaluation of hands-on defibrillation skills of pediatric providers in a simulated VFCA in our children's hospital. Each provider was asked to use pads followed by paddles to provide 2 J/kg shock to an infant mannequin in VFCA. The hands-on skills were evaluated for struggle with any step of defibrillation, defined a priori as >10 s delay with particular step. The data was analyzed using chi-square test with significant p -value 10 s delay) with each of connecting the pads/paddles to the device, using pads/paddles on the mannequin and using buttons on the machine was 34 (50%), 26 (38%), and 31 (46%), respectively. Conclusions: The defibrillation skills of providers in a tertiary care children's hospital are poor. Both human and machine-related factors are associated with delay in defibrillation. Prior use of the study defibrillator is associated with a significantly shorter time-to-first shock as compared to prior use of any other defibrillator or no prior use of any defibrillator.

  4. A Magnetic Resonance Imaging-Conditional External Cardiac Defibrillator for Resuscitation Within the Magnetic Resonance Imaging Scanner Bore.

    Science.gov (United States)

    Schmidt, Ehud J; Watkins, Ronald D; Zviman, Menekhem M; Guttman, Michael A; Wang, Wei; Halperin, Henry A

    2016-10-01

    Subjects undergoing cardiac arrest within a magnetic resonance imaging (MRI) scanner are currently removed from the bore and then from the MRI suite, before the delivery of cardiopulmonary resuscitation and defibrillation, potentially increasing the risk of mortality. This precludes many higher-risk (acute ischemic and acute stroke) patients from undergoing MRI and MRI-guided intervention. An MRI-conditional cardiac defibrillator should enable scanning with defibrillation pads attached and the generator ON, enabling application of defibrillation within the seconds of MRI after a cardiac event. An MRI-conditional external defibrillator may improve patient acceptance for MRI procedures. A commercial external defibrillator was rendered 1.5 Tesla MRI-conditional by the addition of novel radiofrequency filters between the generator and commercial disposable surface pads. The radiofrequency filters reduced emission into the MRI scanner and prevented cable/surface pad heating during imaging, while preserving all the defibrillator monitoring and delivery functions. Human volunteers were imaged using high specific absorption rate sequences to validate MRI image quality and lack of heating. Swine were electrically fibrillated (n=4) and thereafter defibrillated both outside and inside the MRI bore. MRI image quality was reduced by 0.8 or 1.6 dB, with the generator in monitoring mode and operating on battery or AC power, respectively. Commercial surface pads did not create artifacts deeper than 6 mm below the skin surface. Radiofrequency heating was within US Food and Drug Administration guidelines. Defibrillation was completely successful inside and outside the MRI bore. A prototype MRI-conditional defibrillation system successfully defibrillated in the MRI without degrading the image quality or increasing the time needed for defibrillation. It can increase patient acceptance for MRI procedures. © 2016 American Heart Association, Inc.

  5. Cross validation of two partitioning-based sampling approaches in mesocosms containing PCB contaminated field sediment, biota, and activated carbon amendment

    DEFF Research Database (Denmark)

    Nørgaard Schmidt, Stine; Wang, Alice P.; Gidley, Philip T

    2017-01-01

    with multiple thicknesses of silicone and in situ pre-equilibrium sampling with low density polyethylene (LDPE) loaded with performance reference compounds were applied independently to measure polychlorinated biphenyls (PCBs) in mesocosms with (1) New Bedford Harbor sediment (MA, USA), (2) sediment and biota......, and (3) activated carbon amended sediment and biota. The aim was to cross validate the two different sampling approaches. Around 100 PCB congeners were quantified in the two sampling polymers, and the results confirmed the good precision of both methods and were in overall good agreement with recently...... published silicone to LDPE partition ratios. Further, the methods yielded Cfree in good agreement for all three experiments. The average ratio between Cfree determined by the two methods was factor 1.4±0.3 (range: 0.6-2.0), and the results thus cross-validated the two sampling approaches. For future...

  6. Accuracies of genomic breeding values in American Angus beef cattle using K-means clustering for cross-validation

    Directory of Open Access Journals (Sweden)

    Saatchi Mahdi

    2011-11-01

    Full Text Available Abstract Background Genomic selection is a recently developed technology that is beginning to revolutionize animal breeding. The objective of this study was to estimate marker effects to derive prediction equations for direct genomic values for 16 routinely recorded traits of American Angus beef cattle and quantify corresponding accuracies of prediction. Methods Deregressed estimated breeding values were used as observations in a weighted analysis to derive direct genomic values for 3570 sires genotyped using the Illumina BovineSNP50 BeadChip. These bulls were clustered into five groups using K-means clustering on pedigree estimates of additive genetic relationships between animals, with the aim of increasing within-group and decreasing between-group relationships. All five combinations of four groups were used for model training, with cross-validation performed in the group not used in training. Bivariate animal models were used for each trait to estimate the genetic correlation between deregressed estimated breeding values and direct genomic values. Results Accuracies of direct genomic values ranged from 0.22 to 0.69 for the studied traits, with an average of 0.44. Predictions were more accurate when animals within the validation group were more closely related to animals in the training set. When training and validation sets were formed by random allocation, the accuracies of direct genomic values ranged from 0.38 to 0.85, with an average of 0.65, reflecting the greater relationship between animals in training and validation. The accuracies of direct genomic values obtained from training on older animals and validating in younger animals were intermediate to the accuracies obtained from K-means clustering and random clustering for most traits. The genetic correlation between deregressed estimated breeding values and direct genomic values ranged from 0.15 to 0.80 for the traits studied. Conclusions These results suggest that genomic estimates

  7. Accuracies of genomic breeding values in American Angus beef cattle using K-means clustering for cross-validation.

    Science.gov (United States)

    Saatchi, Mahdi; McClure, Mathew C; McKay, Stephanie D; Rolf, Megan M; Kim, JaeWoo; Decker, Jared E; Taxis, Tasia M; Chapple, Richard H; Ramey, Holly R; Northcutt, Sally L; Bauck, Stewart; Woodward, Brent; Dekkers, Jack C M; Fernando, Rohan L; Schnabel, Robert D; Garrick, Dorian J; Taylor, Jeremy F

    2011-11-28

    Genomic selection is a recently developed technology that is beginning to revolutionize animal breeding. The objective of this study was to estimate marker effects to derive prediction equations for direct genomic values for 16 routinely recorded traits of American Angus beef cattle and quantify corresponding accuracies of prediction. Deregressed estimated breeding values were used as observations in a weighted analysis to derive direct genomic values for 3570 sires genotyped using the Illumina BovineSNP50 BeadChip. These bulls were clustered into five groups using K-means clustering on pedigree estimates of additive genetic relationships between animals, with the aim of increasing within-group and decreasing between-group relationships. All five combinations of four groups were used for model training, with cross-validation performed in the group not used in training. Bivariate animal models were used for each trait to estimate the genetic correlation between deregressed estimated breeding values and direct genomic values. Accuracies of direct genomic values ranged from 0.22 to 0.69 for the studied traits, with an average of 0.44. Predictions were more accurate when animals within the validation group were more closely related to animals in the training set. When training and validation sets were formed by random allocation, the accuracies of direct genomic values ranged from 0.38 to 0.85, with an average of 0.65, reflecting the greater relationship between animals in training and validation. The accuracies of direct genomic values obtained from training on older animals and validating in younger animals were intermediate to the accuracies obtained from K-means clustering and random clustering for most traits. The genetic correlation between deregressed estimated breeding values and direct genomic values ranged from 0.15 to 0.80 for the traits studied. These results suggest that genomic estimates of genetic merit can be produced in beef cattle at a young age but

  8. The Cross-Calibration of Spectral Radiances and Cross-Validation of CO2 Estimates from GOSAT and OCO-2

    Directory of Open Access Journals (Sweden)

    Fumie Kataoka

    2017-11-01

    Full Text Available The Greenhouse gases Observing SATellite (GOSAT launched in January 2009 has provided radiance spectra with a Fourier Transform Spectrometer for more than eight years. The Orbiting Carbon Observatory 2 (OCO-2 launched in July 2014, collects radiance spectra using an imaging grating spectrometer. Both sensors observe sunlight reflected from Earth’s surface and retrieve atmospheric carbon dioxide (CO2 concentrations, but use different spectrometer technologies, observing geometries, and ground track repeat cycles. To demonstrate the effectiveness of satellite remote sensing for CO2 monitoring, the GOSAT and OCO-2 teams have worked together pre- and post-launch to cross-calibrate the instruments and cross-validate their retrieval algorithms and products. In this work, we first compare observed radiance spectra within three narrow bands centered at 0.76, 1.60 and 2.06 µm, at temporally coincident and spatially collocated points from September 2014 to March 2017. We reconciled the differences in observation footprints size, viewing geometry and associated differences in surface bidirectional reflectance distribution function (BRDF. We conclude that the spectral radiances measured by the two instruments agree within 5% for all bands. Second, we estimated mean bias and standard deviation of column-averaged CO2 dry air mole fraction (XCO2 retrieved from GOSAT and OCO-2 from September 2014 to May 2016. GOSAT retrievals used Build 7.3 (V7.3 of the Atmospheric CO2 Observations from Space (ACOS algorithm while OCO-2 retrievals used Version 7 of the OCO-2 retrieval algorithm. The mean biases and standard deviations are −0.57 ± 3.33 ppm over land with high gain, −0.17 ± 1.48 ppm over ocean with high gain and −0.19 ± 2.79 ppm over land with medium gain. Finally, our study is complemented with an analysis of error sources: retrieved surface pressure (Psurf, aerosol optical depth (AOD, BRDF and surface albedo inhomogeneity. We found no change in XCO2

  9. Hartrevalidatie bij patiënten met een aangeboren hartafwijking, een implanteerbare defibrillator of chronisch hartfalen.

    NARCIS (Netherlands)

    Brügemann, J.; Postema, K.; van Gelder, I.C.; Oosterwijk, M.H.; van Veldhuisen, D.J.

    2004-01-01

    Cardiac rehabilitation is no longer just used to treat patients after the manifestation of a coronary artery disease such as a myocardial infarct, after a PTCA or after a coronary bypass operation. Patients with a congenital heart disease, patients who have received an implantable cardioverter

  10. Robustness of two single-item self-esteem measures: cross-validation with a measure of stigma in a sample of psychiatric patients.

    Science.gov (United States)

    Bagley, Christopher

    2005-08-01

    Robins' Single-item Self-esteem Inventory was compared with a single item from the Coopersmith Self-esteem. Although a new scoring format was used, there was good evidence of cross-validation in 83 current and former psychiatric patients who completed Harvey's adapted measure of stigma felt and experienced by users of mental health services. Scores on the two single-item self-esteem measures correlated .76 (p self-esteem in users of mental health services.

  11. Attempted development and cross-validation of predictive models of individual-level and organizational-level turnover of nuclear power operators

    International Nuclear Information System (INIS)

    Vasa-Sideris, S.J.

    1989-01-01

    Nuclear power accounts for 209% of the electric power generated in the U.S. by 107 nuclear plants which employ over 8,700 operators. Operator turnover is significant to utilities from the economic point of view since it costs almost three hundred thousand dollars to train and qualify one operator, and because turnover affects plant operability and therefore plant safety. The study purpose was to develop and cross-validate individual-level and organizational-level models of turnover of nuclear power plant operators. Data were obtained by questionnaires and from published data for 1983 and 1984 on a number of individual, organizational, and environmental predictors. Plants had been in operation for two or more years. Questionnaires were returned by 29 out of 50 plants on over 1600 operators. The objectives were to examine the reliability of the turnover criterion, to determine the classification accuracy of the multivariate predictive models and of categories of predictors (individual, organizational, and environmental) and to determine if a homology existed between the individual-level and organizational-level models. The method was to examine the shrinkage that occurred between foldback design (in which the predictive models were reapplied to the data used to develop them) and cross-validation. Results did not support the hypothesis objectives. Turnover data were accurate but not stable between the two years. No significant differences were detected between the low and high turnover groups at the organization or individual level in cross-validation. Lack of stability in the criterion, restriction of range, and small sample size at the organizational level were serious limitations of this study. The results did support the methods. Considerable shrinkage occurred between foldback and cross-validation of the models

  12. Prediction of cognitive and motor development in preterm children using exhaustive feature selection and cross-validation of near-term white matter microstructure.

    Science.gov (United States)

    Schadl, Kornél; Vassar, Rachel; Cahill-Rowley, Katelyn; Yeom, Kristin W; Stevenson, David K; Rose, Jessica

    2018-01-01

    Advanced neuroimaging and computational methods offer opportunities for more accurate prognosis. We hypothesized that near-term regional white matter (WM) microstructure, assessed on diffusion tensor imaging (DTI), using exhaustive feature selection with cross-validation would predict neurodevelopment in preterm children. Near-term MRI and DTI obtained at 36.6 ± 1.8 weeks postmenstrual age in 66 very-low-birth-weight preterm neonates were assessed. 60/66 had follow-up neurodevelopmental evaluation with Bayley Scales of Infant-Toddler Development, 3rd-edition (BSID-III) at 18-22 months. Linear models with exhaustive feature selection and leave-one-out cross-validation computed based on DTI identified sets of three brain regions most predictive of cognitive and motor function; logistic regression models were computed to classify high-risk infants scoring one standard deviation below mean. Cognitive impairment was predicted (100% sensitivity, 100% specificity; AUC = 1) by near-term right middle-temporal gyrus MD, right cingulate-cingulum MD, left caudate MD. Motor impairment was predicted (90% sensitivity, 86% specificity; AUC = 0.912) by left precuneus FA, right superior occipital gyrus MD, right hippocampus FA. Cognitive score variance was explained (29.6%, cross-validated Rˆ2 = 0.296) by left posterior-limb-of-internal-capsule MD, Genu RD, right fusiform gyrus AD. Motor score variance was explained (31.7%, cross-validated Rˆ2 = 0.317) by left posterior-limb-of-internal-capsule MD, right parahippocampal gyrus AD, right middle-temporal gyrus AD. Search in large DTI feature space more accurately identified neonatal neuroimaging correlates of neurodevelopment.

  13. Internal defibrillation: where we have been and where we should be going?

    Science.gov (United States)

    Lévy, Samuel

    2005-08-01

    Internal cardioversion has been developed as an alternative technique for patients who are resistant to external DC cardioversion of atrial fibrillation (AF) and was found to be associated with higher success rates. It used initially high energies (200-300 J) delivered between an intracardiac catheter and a backplate. Subsequent studies have shown that it is possible to terminate with energies of 1 to 6 Joules, paroxysmal or induced AF in 90 percent of patients and persistent AF in 75 percent of patients, using biphasic shocks delivered between a right atrium-coronary sinus vectors. Consequently, internal atrial defibrillation can be performed under sedation only without the need for general anesthesia. Recently developed external defibrillators, capable of delivering biphasic shocks, have increased the success rates of external cardioversion and reduced the need for internal cardioversion. However, internal defibrillation is still useful in overweight or obese patients, in patients with chronic obstructive pulmonary disease or asthma who are more difficult to defibrillate, and in patients with implanted devices which may be injured by high energy shocks. Low energy internal defibrillation has also proven to be safe and this has prompted the development of implantable devices for terminating AF. The first device used was the Metrix system, a stand-alone atrial defibrillator (without ventricular defibrillation) which was found to be safe and effective in selected groups of patients. Unfortunately, this device is no longer being marketed. Only double chamber defibrillators with pacing capabilities are presently available: the Medtronic GEM III AT, an updated version of the Jewel AF and the Guidant PRIZM AVT. These devices can be patient-activated or programmed to deliver automatically ounce atrial tachyarrhythmias are detected, therapies including pacing or/and shocks. Attempts to define the group of patients who might benefit from these devices are described but the

  14. Differences between out-of-hospital cardiac arrest in residential and public locations and implications for public-access defibrillation

    DEFF Research Database (Denmark)

    Folke, Fredrik; Gislason, Gunnar H; Lippert, Freddy

    2010-01-01

    The majority of out-of-hospital cardiac arrests (OHCAs) occur in residential locations, but knowledge about strategic placement of automated external defibrillators in residential areas is lacking. We examined whether residential OHCA areas suitable for placement of automated external defibrillat...... defibrillators could be identified on the basis of demographic characteristics and characterized individuals with OHCA in residential locations....

  15. Effect of Metoprolol Versus Carvedilol on Outcomes in MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy)

    DEFF Research Database (Denmark)

    Ruwald, Martin H; Ruwald, Anne-Christine H; Jøns, Christian

    2013-01-01

    This study sought to compare the effects of metoprolol and carvedilol in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) study.......This study sought to compare the effects of metoprolol and carvedilol in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) study....

  16. Y2K: effects on pacemaker and implantable defibrillator programmers.

    Science.gov (United States)

    Flynn, D P; Daubert, J P; Huang, D T; Ocampo, C M; O'Gorman, E

    1999-01-01

    All permanent pacemakers and implantable defibrillators (PPM/ICDs) will continue to function as programmed without regard to the date in the year 2000 (Y2K). All manufacturers contacted reassured us that some of these devices incorporate a day/year clock in the circuitry; however, these are not involved in sensing or delivering programmed therapy. Some manufacturers' device programmers will roll over to the year 2000 without any problems at all, whereas others may have difficulty with date and time stamping on printed reports. We tested 14 different types of PPM/ICD programmers for Y2K compliance using 8 tests. Five of the 14 models passed each test and were labeled at our institution with a green "Y2K" sticker to identify them as Y2K compatible and needing no special attention after December 31, 1999. The most common test failed was the ability to roll the date forward from December 31, 1999, with the programmer power off. Organizations should consider testing and replacing noncompliant device programmers or placing a red sticker with "Y2K" crossed out on noncompliant pieces. The red sticker alerts the advanced practice nurse or physician to the need to confirm the appropriate date and time in the programmer after startup in the year 2000 and before interrogating or programming any PPM/ICD, to avoid inappropriate date and time stamping on printed reports from that programmer.

  17. Implanted Cardiac Defibrillator Care in Radiation Oncology Patient Population

    International Nuclear Information System (INIS)

    Gelblum, Daphna Y.; Amols, Howard

    2009-01-01

    Purpose: To review the experience of a large cancer center with radiotherapy (RT) patients bearing implantable cardiac defibrillators (ICDs) to propose some preliminary care guidelines as we learn more about the devices and their interaction with the therapeutic radiation environment. Methods and Materials: We collected data on patients with implanted ICDs treated with RT during a 2.5-year period at any of the five Memorial Sloan-Kettering clinical campuses. Information regarding the model, location, and dose detected from the device, as well as the treatment fields, fraction size, and treatment energy was collected. During this time, a new management policy for these patients had been implemented requiring treatment with low-energy beams (6 MV) and close surveillance of the patients in partnership with their electrophysiologist, as they received RT. Results: During the study period, 33 patients were treated with an ICD in place. One patient experienced a default of the device to its initial factory setting that was detected by the patient hearing an auditory signal from the device. This patient had initially been treated with a 15-MV beam. After this episode, his treatment was replanned to be completed with 6-MV photons, and he experienced no further events. Conclusion: Patients with ICDs and other implanted computer-controlled devices will be encountered more frequently in the RT department, and proper management is important. We present a policy for the safe treatment of these patients in the radiation oncology environment.

  18. Availability of Automated External Defibrillators in Public High Schools.

    Science.gov (United States)

    White, Michelle J; Loccoh, Emefah C; Goble, Monica M; Yu, Sunkyung; Duquette, Deb; Davis, Matthew M; Odetola, Folafoluwa O; Russell, Mark W

    2016-05-01

    To assess automated external defibrillator (AED) distribution and cardiac emergency preparedness in Michigan secondary schools and investigate for association with school sociodemographic characteristics. Surveys were sent via electronic mail to representatives from all public high schools in 30 randomly selected Michigan counties, stratified by population. Association of AED-related factors with school sociodemographic characteristics were evaluated using Wilcoxon rank sum test and χ(2) test, as appropriate. Of 188 schools, 133 (71%) responded to the survey and all had AEDs. Larger student population was associated with fewer AEDs per 100 students (P schools. Schools with >20% students from racial minority groups had significantly fewer AEDs available per 100 students than schools with less racial diversity (P = .03). Schools with more students eligible for free and reduced lunch were less likely to have a cardiac emergency response plan (P = .02) and demonstrated less frequent AED maintenance (P = .03). Although AEDs are available at public high schools across Michigan, the number of AEDs per student varies inversely with minority student population and school size. Unequal distribution of AEDs and lack of cardiac emergency preparedness may contribute to outcomes of sudden cardiac arrest among youth. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Psychological Effects of Automated External Defibrillator Training A randomized trial

    Science.gov (United States)

    Meischke, Hendrika; Diehr, Paula; Phelps, Randi; Damon, Susan; Rea, Tom

    2011-01-01

    Objectives The objective of this study was to test if an Automated External Defibrillator (AED) training program would positively affect the mental health of family members of high risk patients. Methods 305 ischemic heart disease patients and their family members were randomized to one of four AED training programs: two video-based training programs and two face-to-face training programs that emphasized self-efficacy and perceived control. Patients and family members were surveyed at baseline, 3 and 9 months post ischemic event on demographic characteristics, measures of quality of life (SF=36) , self-efficacy and perceived control. For this study, family members were the focus rather than the patients. Results Regression analyses showed that family members in the face-to-face training programs did not score better on any of the mental health status variables than family members who participated in the other training programs but for an increase in self-efficacy beliefs at 3 months post training. Conclusion The findings suggest that a specifically designed AED training program emphasizing self-efficacy and perceived control beliefs is not likely to enhance family member mental health. PMID:21411144

  20. Basic study on a lower-energy defibrillation method using computer simulation and cultured myocardial cell models.

    Science.gov (United States)

    Yaguchi, A; Nagase, K; Ishikawa, M; Iwasaka, T; Odagaki, M; Hosaka, H

    2006-01-01

    Computer simulation and myocardial cell models were used to evaluate a low-energy defibrillation technique. A generated spiral wave, considered to be a mechanism of fibrillation, and fibrillation were investigated using two myocardial sheet models: a two-dimensional computer simulation model and a two-dimensional experimental model. A new defibrillation technique that has few side effects, which are induced by the current passing into the patient's body, on cardiac muscle is desired. The purpose of the present study is to conduct a basic investigation into an efficient defibrillation method. In order to evaluate the defibrillation method, the propagation of excitation in the myocardial sheet is measured during the normal state and during fibrillation, respectively. The advantages of the low-energy defibrillation technique are then discussed based on the stimulation timing.

  1. Prediction of fat-free mass by bioelectrical impedance analysis in older adults from developing countries: a cross-validation study using the deuterium dilution method

    International Nuclear Information System (INIS)

    Mateo, H. Aleman; Romero, J. Esparza; Valencia, M.E.

    2010-01-01

    Objective: Several limitations of published bioelectrical impedance analysis (BIA) equations have been reported. The aims were to develop in a multiethnic, elderly population a new prediction equation and cross- validate it along with some published BIA equations for estimating fat-free mass using deuterium oxide dilution as the reference method. Design and setting: Cross-sectional study of elderly from five developing countries. Methods: Total body water (TBW) measured by deuterium dilution was used to determine fat-free mass (FFM) in 383 subjects. Anthropometric and BIA variables were also measured. Only 377 subjects were included for the analysis, randomly divided into development and cross-validation groups after stratified by gender. Stepwise model selection was used to generate the model and Bland Altman analysis was used to test agreement. Results: FFM = 2.95 - 3.89 (Gender) + 0.514 (Ht2/Z) + 0.090 (Waist) + 0.156 (Body weight). The model fit parameters were an R2, total F-Ratio, and the SEE of 0.88, 314.3, and 3.3, respectively. None of the published BIA equations met the criteria for agreement. The new BIA equation underestimated FFM by just 0.3 kg in the cross-validation sample. The mean of the difference between FFM by TBW and the new BIA equation were not significantly different; 95% of the differences were between the limits of agreement of -6.3 to 6.9 kg of FFM. There was no significant association between the mean of the differences and their averages (r= 0.008 and p= 0.2). Conclusions:This new BIA equation offers a valid option compared with some of the current published BIA equations to estimate FFM in elderly subjects from five developing countries. (Authors)

  2. Genome-Wide Association Studies and Comparison of Models and Cross-Validation Strategies for Genomic Prediction of Quality Traits in Advanced Winter Wheat Breeding Lines

    Directory of Open Access Journals (Sweden)

    Peter S. Kristensen

    2018-02-01

    Full Text Available The aim of the this study was to identify SNP markers associated with five important wheat quality traits (grain protein content, Zeleny sedimentation, test weight, thousand-kernel weight, and falling number, and to investigate the predictive abilities of GBLUP and Bayesian Power Lasso models for genomic prediction of these traits. In total, 635 winter wheat lines from two breeding cycles in the Danish plant breeding company Nordic Seed A/S were phenotyped for the quality traits and genotyped for 10,802 SNPs. GWAS were performed using single marker regression and Bayesian Power Lasso models. SNPs with large effects on Zeleny sedimentation were found on chromosome 1B, 1D, and 5D. However, GWAS failed to identify single SNPs with significant effects on the other traits, indicating that these traits were controlled by many QTL with small effects. The predictive abilities of the models for genomic prediction were studied using different cross-validation strategies. Leave-One-Out cross-validations resulted in correlations between observed phenotypes corrected for fixed effects and genomic estimated breeding values of 0.50 for grain protein content, 0.66 for thousand-kernel weight, 0.70 for falling number, 0.71 for test weight, and 0.79 for Zeleny sedimentation. Alternative cross-validations showed that the genetic relationship between lines in training and validation sets had a bigger impact on predictive abilities than the number of lines included in the training set. Using Bayesian Power Lasso instead of GBLUP models, gave similar or slightly higher predictive abilities. Genomic prediction based on all SNPs was more effective than prediction based on few associated SNPs.

  3. Barriers and facilitators to public access defibrillation in out-of-hospital cardiac arrest: a systematic review.

    Science.gov (United States)

    Smith, Christopher M; Lim Choi Keung, Sarah N; Khan, Mohammed O; Arvanitis, Theodoros N; Fothergill, Rachael; Hartley-Sharpe, Christopher; Wilson, Mark H; Perkins, Gavin D

    2017-10-01

    Public access defibrillation initiatives make automated external defibrillators available to the public. This facilitates earlier defibrillation of out-of-hospital cardiac arrest victims and could save many lives. It is currently only used for a minority of cases. The aim of this systematic review was to identify barriers and facilitators to public access defibrillation. A comprehensive literature review was undertaken defining formal search terms for a systematic review of the literature in March 2017. Studies were included if they considered reasons affecting the likelihood of public access defibrillation and presented original data. An electronic search strategy was devised searching MEDLINE and EMBASE, supplemented by bibliography and related-article searches. Given the low-quality and observational nature of the majority of articles, a narrative review was performed. Sixty-four articles were identified in the initial literature search. An additional four unique articles were identified from the electronic search strategies. The following themes were identified related to public access defibrillation: knowledge and awareness; willingness to use; acquisition and maintenance; availability and accessibility; training issues; registration and regulation; medicolegal issues; emergency medical services dispatch-assisted use of automated external defibrillators; automated external defibrillator-locator systems; demographic factors; other behavioural factors. In conclusion, several barriers and facilitators to public access defibrillation deployment were identified. However, the evidence is of very low quality and there is not enough information to inform changes in practice. This is an area in urgent need of further high-quality research if public access defibrillation is to be increased and more lives saved. PROSPERO registration number CRD42016035543. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions

  4. [Training program on cardiopulmonary resuscitation with the use of automated external defibrillator in a university].

    Science.gov (United States)

    Boaventura, Ana Paula; Miyadahira, Ana Maria Kazue

    2012-03-01

    Early defibrillation in cardiopulmonary resuscitation (CPR) receives increasing emphasis on its priority and rapidity. This is an experience report about the implementation of a training program in CPR using a defibrillator in a private university. The training program in basic CPR maneuvers was based on global guidelines, including a theorical course with practical demonstration of CPR maneuvers with the defibrillator, individual practical training and theoretical and practical assessments. About the performance of students in the practical assessment the mean scores obtained by students in the first stage of the course was 26.4 points, while in the second stage the mean was 252.8 points, in the theoretical assessment the mean in the first stage was 3.06 points and in the second 9.0 points. The implementation of programs like this contribute to the effective acquisition of knowledge (theory) and skill (pratice) for the care of CPR victims.

  5. Use and benefits of public access defibrillation in a nation-wide network

    DEFF Research Database (Denmark)

    Nielsen, Anne Møller; Folke, Fredrik; Lippert, Freddy Knudsen

    2013-01-01

    BACKGROUND: Automated External Defibrillators (AEDs) are known to increase survival after out-of-hospital cardiac arrest (OHCA). The aim of this study was to examine the use and benefit of public-access defibrillation (PAD) in a nation-wide network. We primarily sought to assess survival at 1 month...... to exercise (42% vs. 0%), and with improved 30-day survival (69% vs. 15%, p=0.001). Among those presenting with a shockable rhythm, 20 (65%) had Return of Spontaneous Circulation upon arrival of EMS and 8 (26%) were conscious, which emphasizes the diagnostic value of ECG downloads from AEDs. Survival could...

  6. Access to automatic defibrillation at airports on an example of Warsaw Chopin Airport

    Directory of Open Access Journals (Sweden)

    Witold Pawłowski

    2017-08-01

    Full Text Available Sudden cardiac arrest and cessation of blood circulation is the most common cause of death of people around the world. Immediate notification of emergency services and cardiopulmonary resuscitation combined with an automatic external defibrillator (AED increases the chances of survivors. Warsaw Chopin Airport is the only public place in Poland and the third one in Europe where a complex and integrated life saving system has been implemented in the ICC. The paper presents an analysis of the access to automatic defibrillation at airports at the Warsaw Chopin Airport

  7. Derivation and Cross-Validation of Cutoff Scores for Patients With Schizophrenia Spectrum Disorders on WAIS-IV Digit Span-Based Performance Validity Measures.

    Science.gov (United States)

    Glassmire, David M; Toofanian Ross, Parnian; Kinney, Dominique I; Nitch, Stephen R

    2016-06-01

    Two studies were conducted to identify and cross-validate cutoff scores on the Wechsler Adult Intelligence Scale-Fourth Edition Digit Span-based embedded performance validity (PV) measures for individuals with schizophrenia spectrum disorders. In Study 1, normative scores were identified on Digit Span-embedded PV measures among a sample of patients (n = 84) with schizophrenia spectrum diagnoses who had no known incentive to perform poorly and who put forth valid effort on external PV tests. Previously identified cutoff scores resulted in unacceptable false positive rates and lower cutoff scores were adopted to maintain specificity levels ≥90%. In Study 2, the revised cutoff scores were cross-validated within a sample of schizophrenia spectrum patients (n = 96) committed as incompetent to stand trial. Performance on Digit Span PV measures was significantly related to Full Scale IQ in both studies, indicating the need to consider the intellectual functioning of examinees with psychotic spectrum disorders when interpreting scores on Digit Span PV measures. © The Author(s) 2015.

  8. Comparison of a new expert elicitation model with the Classical Model, equal weights and single experts, using a cross-validation technique

    Energy Technology Data Exchange (ETDEWEB)

    Flandoli, F. [Dip.to di Matematica Applicata, Universita di Pisa, Pisa (Italy); Giorgi, E. [Dip.to di Matematica Applicata, Universita di Pisa, Pisa (Italy); Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Pisa, via della Faggiola 32, 56126 Pisa (Italy); Aspinall, W.P. [Dept. of Earth Sciences, University of Bristol, and Aspinall and Associates, Tisbury (United Kingdom); Neri, A., E-mail: neri@pi.ingv.it [Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Pisa, via della Faggiola 32, 56126 Pisa (Italy)

    2011-10-15

    The problem of ranking and weighting experts' performances when quantitative judgments are being elicited for decision support is considered. A new scoring model, the Expected Relative Frequency model, is presented, based on the closeness between central values provided by the expert and known values used for calibration. Using responses from experts in five different elicitation datasets, a cross-validation technique is used to compare this new approach with the Cooke Classical Model, the Equal Weights model, and individual experts. The analysis is performed using alternative reward schemes designed to capture proficiency either in quantifying uncertainty, or in estimating true central values. Results show that although there is only a limited probability that one approach is consistently better than another, the Cooke Classical Model is generally the most suitable for assessing uncertainties, whereas the new ERF model should be preferred if the goal is central value estimation accuracy. - Highlights: > A new expert elicitation model, named Expected Relative Frequency (ERF), is presented. > A cross-validation approach to evaluate the performance of different elicitation models is applied. > The new ERF model shows the best performance with respect to the point-wise estimates.

  9. Defibrillator patients should not be denied a peaceful death.

    Science.gov (United States)

    Westerdahl, Annika Kinch; Sutton, Richard; Frykman, Viveka

    2015-03-01

    Implantable defibrillators (ICDs) prevent sudden cardiac death. With declining health, ICD therapy may prolong death and expose the patient to unnecessary pain and anxiety. Few studies have addressed end of life care in ICD patients. The objective of this study was to investigate end of life in ICD patients, with respect to location of death; duration between do-not-resuscitate (DNR)-orders and deactivation of ICD therapy or DNR and time of death. A descriptive analysis of 65 deceased ICD patients, all whom had a written DNR-order before death, is presented. The majority (86%) was treated in hospitals, mainly (63%) university hospitals, and many (33%) in cardiology wards. Despite DNR-order, ICD shock therapy was active in 51% of all patients. In those with therapy deactivated at death, therapy deactivation was carried out two days or more after DNR-order in more than a third (38%). The time from DNR decision to death in patients with therapy active had a median of four days (IQR 1-38). During the last 24h of life, 24% of the patients experienced shock treatment. The majority of ICD patients with a DNR-order were treated in university hospitals. More than half still had shock treatment active at time of death with a median of four days or more between DNR decision and death. Patients with therapy deactivated, two days or more elapsed in more than a third from DNR decision to deactivation of therapy, exposing patients to a high risk of painful shocks before death. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. The utilization of automated external defibrillators in Taiwan.

    Science.gov (United States)

    Wang, Tsung-Hsi; Wu, Hsi-Wen; Hou, Peter C; Tseng, Hao-Jui

    2018-03-24

    Increasing attention to care of patient succumbed to out-of-hospital cardiac arrest (OHCA) and evidence for improved survival have resulted in many countries to encourage the use automated external defibrillators (AEDs) by legislation. In Taiwan, the amendment of the Emergency Medical Services Act mandated the installation of AEDs in designated areas in 2013. Since then, 6151 AEDs have been installed and registered in mandated and non-mandated locations. The purpose of this study was to investigate the utilization of AEDs at mandated and non-mandated locations. This paper analyzed 217 cases in whom AEDs was used between July 11, 2013 and July 31, 2015. Descriptive statistics were used to analyze the data. The highest frequency of AEDs used was in long-term care facilities, accounting for 34 (15.7%) cases. The second and third highest was in schools and commuting stations. The highest utilization rate of registered AED was in long-term care facilities (73.9%), the second was in residential areas, and the third was in hot spring areas. Employees at the designated locations or medical personnel operated the AED in 143 cases (84.6%), and bystanders, relatives, friends or others operated the AEDs in 26 cases (15.4%). On-site Return of Spontaneous Circulation (ROSC) after applying AEDs occurred in 76 cases (45.8%). Long-term care facilities had the highest utilization of AEDs and government should pay more attention to enforce the installing of AEDs in these places. The government also needs to promote the education public on how to search the AEDs locations. Copyright © 2018. Published by Elsevier B.V.

  11. Comparison of Sprint Fidelis and Riata defibrillator lead failure rates.

    Science.gov (United States)

    Fazal, Iftikhar A; Shepherd, Ewen J; Tynan, Margaret; Plummer, Christopher J; McComb, Janet M

    2013-09-30

    Sprint Fidelis and Riata defibrillator leads are prone to early failure. Few data exist on the comparative failure rates and mortality related to lead failure. The aims of this study were to determine the failure rate of Sprint Fidelis and Riata leads, and to compare failure rates and mortality rates in both groups. Patients implanted with Sprint Fidelis leads and Riata leads at a single centre were identified and in July 2012, records were reviewed to ascertain lead failures, deaths, and relationship to device/lead problems. 113 patients had Sprint Fidelis leads implanted between June 2005 and September 2007; Riata leads were implanted in 106 patients between January 2003 and February 2008. During 53.0 ± 22.3 months of follow-up there were 13 Sprint Fidelis lead failures (11.5%, 2.60% per year) and 25 deaths. Mean time to failure was 45.1 ± 15.5 months. In the Riata lead cohort there were 32 deaths, and 13 lead failures (11.3%, 2.71% per year) over 54.8 ± 26.3 months follow-up with a mean time to failure of 53.5 ± 24.5 months. There were no significant differences in the lead failure-free Kaplan-Meier survival curve (p=0.77), deaths overall (p=0.17), or deaths categorised as sudden/cause unknown (p=0.54). Sprint Fidelis and Riata leads have a significant but comparable failure rate at 2.60% per year and 2.71% per year of follow-up respectively. The number of deaths in both groups is similar and no deaths have been identified as being related to lead failure in either cohort. Copyright © 2012. Published by Elsevier Ireland Ltd.

  12. Cardiogenic Shock and Lung Injury as a Complication of Defibrillation

    Directory of Open Access Journals (Sweden)

    Hasan Serdar Kıhtır

    2017-12-01

    Full Text Available Local burns, embolism, and arrhythmia are the most common side effects observed after electrical shock treatments. However, systolic function may be rarely affected and pulmonary edema may develop. The cases of pulmonary edema after electrical shock treatments have been reported since 1960s and the proposed mechanism is the inadequacy of the left atrium cuff and ventricle. It was learned that a 7-year-old-girl without any known disease except vesicoureteral reflux had a ventricular fibrillation during general anesthesia induction and defibrillation at 2 joule/kg was attempted. It was also learned that the procedure was delayed and the patient was diagnosed with a long QT (QTc: 0.47 ms and had respiratory distress and circulatory disturbances after four hours. Pulmonary edema and heart failure was determined, and due to hipoxemia (SpO2 <88% not getting any better with non-invasive ventilation, the patient was intubated and followed with mechanical ventilation. A thermodilution catheter was inserted into the femoral artery and a low cardiac index (CI: 1.58 L/min/m2, elevated extravascular lung water index (EVLWI: 18 mL/kg and high pulmonary vascular permeability index (PVPI: 7.6 were determined. The patient was treated by mechanical ventilation and vasoactive/inotropic management and discharged at the fifth day of hospitalization without any sequela. Having high EVLWI with high PVPI suggest that the pulmonary edema mechanism may also be caused by alveolocapillary membrane damage, which is not accompanied by heart failure alone. This case is presented to show that it is the first child in the literature and that the results of transpulmonary thermodilution can also give information about lung function as well as cardiac function.

  13. Interprofessional education and social interaction: The use of automated external defibrillators in team-based basic life support.

    Science.gov (United States)

    Onan, Arif; Simsek, Nurettin

    2017-04-01

    Automated external defibrillators are pervasive computing devices designed for the treatment and management of acute sudden cardiac arrest. This study aims to explain users' actual use behavior in teams formed by different professions taken after a short time span of interaction with automated external defibrillator. Before the intervention, all the participants were certified with the American Heart Association Basic Life Support for healthcare providers. A statistically significant difference was revealed in mean individual automated external defibrillator technical skills between uniprofessional and interprofessional groups. The technical automated external defibrillator team scores were greater for groups with interprofessional than for those with uniprofessional education. The nontechnical automated external defibrillator skills of interprofessional and uniprofessional teams revealed differences in advantage of interprofessional teams. Students positively accept automated external defibrillators if well-defined and validated training opportunities to use them expertly are available. Uniprofessional teams were successfully supported by their members and, thereby, used automated external defibrillator effectively. Furthermore, the interprofessional approach resulted in as much effective teamwork as the uniprofessional approach.

  14. End-tidal carbon dioxide and defibrillation success in out-of-hospital cardiac arrest.

    Science.gov (United States)

    Savastano, Simone; Baldi, Enrico; Raimondi, Maurizio; Palo, Alessandra; Belliato, Mirko; Cacciatore, Elisa; Corazza, Valentina; Molinari, Simone; Canevari, Fabrizio; Danza, Aurora I; De Ferrari, Gaetano M; Iotti, Giorgio Antonio; Visconti, Luigi Oltrona

    2017-12-01

    Basing on the relationship between the quality of cardiopulmonary resuscitation (CPR) and the responsiveness of VF to the defibrillation we aimed to assess whether the values of ETCO2 in the minute before defibrillation could predict the effectiveness of the shock. We retrospectively evaluated the reports generated by the manual monitor/defibrillator (Corpuls by GS Elektromedizinische Geräte G. Stemple GmbH, Germany) used for cases of VF cardiac arrest from January 2015 to December 2016. The mean ETCO2 value of the minute preceding the shock (METCO2 60 ) was computed. A blind evaluation of the effectiveness of each shock was provided by three cardiologists. A total amount of 207 shocks were delivered for 62 patients. When considering the three tertiles of METCO2 60 (T1:METCO2 60 ≤ 20mmHg; T2: 20mmHg 31mmHg) a statistically significant difference between the percentages of shock success was found (T1: 50%; T2: 63%; T3: 78%; Chi square p=0.003; p for trend CPR, monitored via ETCO2, and suggest ETCO2 monitoring as an additional weapon to guide defibrillation. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Vernakalant selectively prolongs atrial refractoriness with no effect on ventricular refractoriness or defibrillation threshold in pigs.

    Science.gov (United States)

    Bechard, Jeff; Gibson, John Ken; Killingsworth, Cheryl R; Wheeler, Jeffery J; Schneidkraut, Marlowe J; Huang, Jian; Ideker, Raymond E; McAfee, Donald A

    2011-03-01

    Vernakalant is a novel antiarrhythmic agent that has demonstrated clinical efficacy for the treatment of atrial fibrillation. Vernakalant blocks, to various degrees, cardiac sodium and potassium channels with a pattern that suggests atrial selectivity. We hypothesized, therefore, that vernakalant would affect atrial more than ventricular effective refractory period (ERP) and have little or no effect on ventricular defibrillation threshold (DFT). Atrial and ventricular ERP and ventricular DFT were determined before and after treatment with vernakalant or vehicle in 23 anesthetized male mixed-breed pigs. Vernakalant was infused at a rate designed to achieve stable plasma levels similar to those in human clinical trials. Atrial and ventricular ERP were determined by endocardial extrastimuli delivered to the right atria or right ventricle. Defibrillation was achieved using external biphasic shocks delivered through adhesive defibrillation patches placed on the thorax after 10 seconds of electrically induced ventricular fibrillation. The DFT was estimated using the Dixon "up-and-down" method. Vernakalant significantly increased atrial ERP compared with vehicle controls (34 ± 8 versus 9 ± 7 msec, respectively) without significantly affecting ventricular ERP or DFT. This is consistent with atrial selective actions and supports the conclusion that vernakalant does not alter the efficacy of electrical defibrillation.

  16. Data management in automated external defibrillators: a call for a standardised solution

    DEFF Research Database (Denmark)

    Nielsen, Anne Møller; Rasmussen, L S

    2011-01-01

    The ECG data stored in automated external defibrillators (AEDs) may be valuable for establishing a final diagnosis and deciding further diagnostics and treatment. Different data management systems are used and this may create significant problems for data storage and access for physicians treating...

  17. Success and failure of the defibrillation shock: insights from a simulation study.

    Science.gov (United States)

    Skouibine, K; Trayanova, N; Moore, P

    2000-07-01

    This simulation study presents a further inquiry into the mechanisms by which a strong electric shock fails to halt life-threatening cardiac arrhythmias. The research uses a model of the defibrillation process that represents a sheet of myocardium as a bidomain. The tissue consists of nonuniformly curved fibers in which spiral wave reentry is initiated. Monophasic defibrillation shocks are delivered via two line electrodes that occupy opposite tissue boundaries. In some simulation experiments, the polarity of the shock is reversed. Electrical activity in the sheet is compared for failed and successful shocks under controlled conditions. The maps of transmembrane potential and activation times calculated during and after the shock demonstrate that weak shocks fail to terminate the reentrant activity via two major mechanisms. As compared with strong shocks, weak shocks result in (1) smaller extension of refractoriness in the areas depolarized by the shock, and (2) slower or incomplete activation of the excitable gap created by deexcitation of the negatively polarized areas. In its turn, mechanism 2 is associated with one or more of the following events: (a) lack of some break excitations, (b) latency in the occurrence of the break excitations, and (c) slower propagation through deexcited areas. Reversal of shock polarity results in a change of the extent of the regions of deexcitation, and thus, in a change in defibrillation threshold. The results of this study indicate the paramount importance of shock-induced deexcitation in both defibrillation and postshock arrhythmogenesis.

  18. [Worldwide experience with automated external defibrillators: What have we achieved? What else can we expect?].

    Science.gov (United States)

    Trappe, Hans-Joachim

    2016-03-01

    In Germany approximately 70,000-100,000 SCD patients die from sudden cardiac death (SCD). SCD is not caused by a single factor but is a multifactorial problem. In 50 % of SCD victims, sudden cardiac death is the first manifestation of heart disease. SCD is caused by ventricular tachyarrhythmias in approximately 90 % of patients, whereas SCD is caused by bradyarrhythmias in 5-10 % of the patients. Risk stratification is not possible in the majority of them prior to the fatal event. Early defibrillation is the method of choice to terminate ventricular fibrillation. Therefore, it is mandatory to install automatic external defibrillators (AED) in places with many people. There is general agreement that early defibrillation with automated external defibrillators (AED) is an effective tool to treat patients with ventricular fibrillation and will improve survival. It seems necessary to teach cardiocompression and AED use, also to children and adolescents. AED therapy "at home" did not improve survival in patients with cardiac arrest and can not be recommended.

  19. Cross-Validation of a Glucose-Insulin-Glucagon Pharmacodynamics Model for Simulation using Data from Patients with Type 1 Diabetes

    DEFF Research Database (Denmark)

    Wendt, Sabrina Lyngbye; Ranjan, Ajenthen; Møller, Jan Kloppenborg

    2017-01-01

    three PD model test fits in each of the seven subjects. Thus, we successfully validated the PD model by leave-one-out cross-validation in seven out of eight T1D patients. Conclusions: The PD model accurately simulates glucose excursions based on plasma insulin and glucagon concentrations. The reported...... for concentrations of glucagon, insulin, and glucose. We fitted pharmacokinetic (PK) models to insulin and glucagon data using maximum likelihood and maximum a posteriori estimation methods. Similarly, we fitted a pharmacodynamic (PD) model to glucose data. The PD model included multiplicative effects of insulin...... and glucagon on EGP. Bias and precision of PD model test fits were assessed by mean predictive error (MPE) and mean absolute predictive error (MAPE). Results: Assuming constant variables in a subject across nonoutlier visits and using thresholds of ±15% MPE and 20% MAPE, we accepted at least one and at most...

  20. Cross-validation of theoretically quantified fiber continuum generation and absolute pulse measurement by MIIPS for a broadband coherently controlled optical source

    DEFF Research Database (Denmark)

    Tu, H.; Liu, Y.; Lægsgaard, Jesper

    2012-01-01

    source with the MIIPS-integrated pulse shaper produces compressed transform-limited 9.6 fs (FWHM) pulses or arbitrarily shaped pulses at a central wavelength of 1020 nm, an average power over 100 mW, and a repetition rate of 76 MHz. In comparison to the 229-fs pump laser pulses that generate the fiber......The predicted spectral phase of a fiber continuum pulsed source rigorously quantified by the scalar generalized nonlinear Schrödinger equation is found to be in excellent agreement with that measured by multiphoton intrapulse interference phase scan (MIIPS) with background subtraction. This cross......-validation confirms the absolute pulse measurement by MIIPS and the transform-limited compression of the fiber continuum pulses by the pulse shaper performing the MIIPS measurement, and permits the subsequent coherent control on the fiber continuum pulses by this pulse shaper. The combination of the fiber continuum...

  1. Body fat measurement by bioelectrical impedance and air displacement plethysmography: a cross-validation study to design bioelectrical impedance equations in Mexican adults

    Directory of Open Access Journals (Sweden)

    Valencia Mauro E

    2007-08-01

    Full Text Available Abstract Background The study of body composition in specific populations by techniques such as bio-impedance analysis (BIA requires validation based on standard reference methods. The aim of this study was to develop and cross-validate a predictive equation for bioelectrical impedance using air displacement plethysmography (ADP as standard method to measure body composition in Mexican adult men and women. Methods This study included 155 male and female subjects from northern Mexico, 20–50 years of age, from low, middle, and upper income levels. Body composition was measured by ADP. Body weight (BW, kg and height (Ht, cm were obtained by standard anthropometric techniques. Resistance, R (ohms and reactance, Xc (ohms were also measured. A random-split method was used to obtain two samples: one was used to derive the equation by the "all possible regressions" procedure and was cross-validated in the other sample to test predicted versus measured values of fat-free mass (FFM. Results and Discussion The final model was: FFM (kg = 0.7374 * (Ht2 /R + 0.1763 * (BW - 0.1773 * (Age + 0.1198 * (Xc - 2.4658. R2 was 0.97; the square root of the mean square error (SRMSE was 1.99 kg, and the pure error (PE was 2.96. There was no difference between FFM predicted by the new equation (48.57 ± 10.9 kg and that measured by ADP (48.43 ± 11.3 kg. The new equation did not differ from the line of identity, had a high R2 and a low SRMSE, and showed no significant bias (0.87 ± 2.84 kg. Conclusion The new bioelectrical impedance equation based on the two-compartment model (2C was accurate, precise, and free of bias. This equation can be used to assess body composition and nutritional status in populations similar in anthropometric and physical characteristics to this sample.

  2. Remote sensing and GIS-based landslide hazard analysis and cross-validation using multivariate logistic regression model on three test areas in Malaysia

    Science.gov (United States)

    Pradhan, Biswajeet

    2010-05-01

    This paper presents the results of the cross-validation of a multivariate logistic regression model using remote sensing data and GIS for landslide hazard analysis on the Penang, Cameron, and Selangor areas in Malaysia. Landslide locations in the study areas were identified by interpreting aerial photographs and satellite images, supported by field surveys. SPOT 5 and Landsat TM satellite imagery were used to map landcover and vegetation index, respectively. Maps of topography, soil type, lineaments and land cover were constructed from the spatial datasets. Ten factors which influence landslide occurrence, i.e., slope, aspect, curvature, distance from drainage, lithology, distance from lineaments, soil type, landcover, rainfall precipitation, and normalized difference vegetation index (ndvi), were extracted from the spatial database and the logistic regression coefficient of each factor was computed. Then the landslide hazard was analysed using the multivariate logistic regression coefficients derived not only from the data for the respective area but also using the logistic regression coefficients calculated from each of the other two areas (nine hazard maps in all) as a cross-validation of the model. For verification of the model, the results of the analyses were then compared with the field-verified landslide locations. Among the three cases of the application of logistic regression coefficient in the same study area, the case of Selangor based on the Selangor logistic regression coefficients showed the highest accuracy (94%), where as Penang based on the Penang coefficients showed the lowest accuracy (86%). Similarly, among the six cases from the cross application of logistic regression coefficient in other two areas, the case of Selangor based on logistic coefficient of Cameron showed highest (90%) prediction accuracy where as the case of Penang based on the Selangor logistic regression coefficients showed the lowest accuracy (79%). Qualitatively, the cross

  3. Late Ratchet syndrome involving isolated left ventricular lead dislodgement post-cardiac resynchronization therapy defibrillator generator change.

    Science.gov (United States)

    Tan, Vern Hsen; Wong, Kelvin

    2018-04-01

    Lead dislodgement following cardiac implantable electronic device (CIED) generator change is rare. We report a case including the postulate mechanism of an isolated left ventricular lead dislodgement 3 months after cardiac resynchronization therapy defibrillator pulse generator change.

  4. Evaluation of a novel ventricular support device with defibrillation capabilities in canine and porcine animal models.

    Science.gov (United States)

    Killingsworth, Cheryl R; Rippy, Marian K; Virmani, Renu; Rollins, Dennis L; McGiffin, David C; Ideker, Raymond E

    2008-08-01

    Sudden death is prevalent in heart failure patients. We tested an implantable ventricular support device consisting of a wireform harness with one or two pairs of integrated defibrillation electrode coils. The device was implanted into six pigs (36-44 kg) through a subxiphoid incision. Peak voltage (V) defibrillation thresholds (DFT) were determined for five test configurations compared with a control transvenous lead (RV to CanPect). Defibrillator can location (abdominal or pectoral) and common coil separation on the implant (0 degrees or 60 degrees ) were studied.(.) The DFT for RV60 to LV60 + CanPect was significantly less than control (348 +/- 57 vs 473 +/- 27 V, P < 0.05). The DFTs for other vectors were similar to control except for RV0 to LV0 + CanAbd (608 +/- 159 V). The device was implanted into 12 adult dogs for 42, 90, or 180 days with DFT and pathological examination performed at the terminal study. Cardiac pressures were determined at baseline, after implantation, and at the terminal study. The DFT was also determined in a separate group of four dogs at 42 days following implantation of the support device with one pair of defibrillation electrodes. The DFTs at implant and explant in dogs with one pair (8 +/- 1.5 Joules [J] and 6 +/- 1.9 J) or two pairs (8 +/- 3.4 J and 7 +/- 1.9 J) of defibrillation electrodes were not significantly different from each other but significantly less than control measured at the terminal study (18 +/- 3.4 J). Left-sided pressures were significantly decreased at explant but within expected normal ranges. Right-sided pressures were not different except for RV systolic. Histopathology indicated mild to moderate epicardial inflammation and fibrosis, consistent with a foreign body healing response. This defibrillation-enabled ventricular support system maintained mechanical functionality for up to 6 months while inducing typical chronic healing responses. The DFT was equal to or lower than a standard transvenous vector.

  5. The number of prehospital defibrillation shocks and 1-month survival in patients with out-of-hospital cardiac arrest.

    Science.gov (United States)

    Hasegawa, Manabu; Abe, Takeru; Nagata, Takashi; Onozuka, Daisuke; Hagihara, Akihito

    2015-04-17

    The relationship between the number of pre-hospital defibrillation shocks and treatment outcome in patients with out-of-hospital cardiac arrest (OHCA) presenting with ventricular fibrillation (VF) is unknown currently. We examined the association between the number of pre-hospitalization defibrillation shocks and 1-month survival in OHCA patients. We conducted a prospective observational study using national registry data obtained from patients with OHCA between January 1, 2009 and December 31, 2012 in Japan. The study subjects were ≥ 18-110 years of age, had suffered from an OHCA before arrival of EMS personnel, had a witnessed collapse, had an initial rhythm that was shockable [VF/ventricular tachycardia (pulseless VT)], were not delivered a shock using a public automated external defibrillator (AED), received one or more shocks using a biphasic defibrillator by EMS personnel, and were transported to a medical institution between January 1, 2009 and December 31, 2012. There were 20,851 OHCA cases which met the inclusion criteria during the study period. Signal detection analysis was used to identify the cutoff point in the number of prehospital defibrillation shocks most closely related to one-month survival. Variables related to the number of defibrillations or one-month survival in OHCA were identified using multiple logistic regression analysis. A cutoff point in the number of pre-hospital defibrillation shocks most closely associated with 1-month OHCA survival was between two and three (χ(2) = 209.61, p < 0.0001). Among those patients who received two shocks or less, 34.48% survived for at least 1 month, compared with 24.75% of those who received three shocks or more. The number of defibrillations (odds ratio [OR] = 1.19, 95% CI: 1.03, 1.38), OHCA origin (OR = 2.81, 95% CI: 2.26, 3.49), use of ALS devices (OR = 0.68, 95% CI: 0.59, 0.79), use of epinephrine (OR = 0.33, 95% C: 0.28, 0.39), interval between first defibrillation and first ROSC (OR = 1.45, 95

  6. Simultaneous estimation of cross-validation errors in least squares collocation applied for statistical testing and evaluation of the noise variance components

    Science.gov (United States)

    Behnabian, Behzad; Mashhadi Hossainali, Masoud; Malekzadeh, Ahad

    2018-02-01

    The cross-validation technique is a popular method to assess and improve the quality of prediction by least squares collocation (LSC). We present a formula for direct estimation of the vector of cross-validation errors (CVEs) in LSC which is much faster than element-wise CVE computation. We show that a quadratic form of CVEs follows Chi-squared distribution. Furthermore, a posteriori noise variance factor is derived by the quadratic form of CVEs. In order to detect blunders in the observations, estimated standardized CVE is proposed as the test statistic which can be applied when noise variances are known or unknown. We use LSC together with the methods proposed in this research for interpolation of crustal subsidence in the northern coast of the Gulf of Mexico. The results show that after detection and removing outliers, the root mean square (RMS) of CVEs and estimated noise standard deviation are reduced about 51 and 59%, respectively. In addition, RMS of LSC prediction error at data points and RMS of estimated noise of observations are decreased by 39 and 67%, respectively. However, RMS of LSC prediction error on a regular grid of interpolation points covering the area is only reduced about 4% which is a consequence of sparse distribution of data points for this case study. The influence of gross errors on LSC prediction results is also investigated by lower cutoff CVEs. It is indicated that after elimination of outliers, RMS of this type of errors is also reduced by 19.5% for a 5 km radius of vicinity. We propose a method using standardized CVEs for classification of dataset into three groups with presumed different noise variances. The noise variance components for each of the groups are estimated using restricted maximum-likelihood method via Fisher scoring technique. Finally, LSC assessment measures were computed for the estimated heterogeneous noise variance model and compared with those of the homogeneous model. The advantage of the proposed method is the

  7. Cross-validation of the factorial structure of the Neighborhood Environment Walkability Scale (NEWS and its abbreviated form (NEWS-A

    Directory of Open Access Journals (Sweden)

    Cerin Ester

    2009-06-01

    Full Text Available Abstract Background The Neighborhood Environment Walkability Scale (NEWS and its abbreviated form (NEWS-A assess perceived environmental attributes believed to influence physical activity. A multilevel confirmatory factor analysis (MCFA conducted on a sample from Seattle, WA showed that, at the respondent level, the factor-analyzable items of the NEWS and NEWS-A measured 11 and 10 constructs of perceived neighborhood environment, respectively. At the census blockgroup (used by the US Census Bureau as a subunit of census tracts level, the MCFA yielded five factors for both NEWS and NEWS-A. The aim of this study was to cross-validate the individual- and blockgroup-level measurement models of the NEWS and NEWS-A in a geographical location and population different from those used in the original validation study. Methods A sample of 912 adults was recruited from 16 selected neighborhoods (116 census blockgroups in the Baltimore, MD region. Neighborhoods were stratified according to their socio-economic status and transport-related walkability level measured using Geographic Information Systems. Participants self-completed the NEWS. MCFA was used to cross-validate the individual- and blockgroup-level measurement models of the NEWS and NEWS-A. Results The data provided sufficient support for the factorial validity of the original individual-level measurement models, which consisted of 11 (NEWS and 10 (NEWS-A correlated factors. The original blockgroup-level measurement model of the NEWS and NEWS-A showed poor fit to the data and required substantial modifications. These included the combining of aspects of building aesthetics with safety from crime into one factor; the separation of natural aesthetics and building aesthetics into two factors; and for the NEWS-A, the separation of presence of sidewalks/walking routes from other infrastructure for walking. Conclusion This study provided support for the generalizability of the individual

  8. Cross validation of gas chromatography-flame photometric detection and gas chromatography-mass spectrometry methods for measuring dialkylphosphate metabolites of organophosphate pesticides in human urine.

    Science.gov (United States)

    Prapamontol, Tippawan; Sutan, Kunrunya; Laoyang, Sompong; Hongsibsong, Surat; Lee, Grace; Yano, Yukiko; Hunter, Ronald Elton; Ryan, P Barry; Barr, Dana Boyd; Panuwet, Parinya

    2014-01-01

    We report two analytical methods for the measurement of dialkylphosphate (DAP) metabolites of organophosphate pesticides in human urine. These methods were independently developed/modified and implemented in two separate laboratories and cross validated. The aim was to develop simple, cost effective, and reliable methods that could use available resources and sample matrices in Thailand and the United States. While several methods already exist, we found that direct application of these methods required modification of sample preparation and chromatographic conditions to render accurate, reliable data. The problems encountered with existing methods were attributable to urinary matrix interferences, and differences in the pH of urine samples and reagents used during the extraction and derivatization processes. Thus, we provide information on key parameters that require attention during method modification and execution that affect the ruggedness of the methods. The methods presented here employ gas chromatography (GC) coupled with either flame photometric detection (FPD) or electron impact ionization-mass spectrometry (EI-MS) with isotopic dilution quantification. The limits of detection were reported from 0.10ng/mL urine to 2.5ng/mL urine (for GC-FPD), while the limits of quantification were reported from 0.25ng/mL urine to 2.5ng/mL urine (for GC-MS), for all six common DAP metabolites (i.e., dimethylphosphate, dimethylthiophosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate, and diethyldithiophosphate). Each method showed a relative recovery range of 94-119% (for GC-FPD) and 92-103% (for GC-MS), and relative standard deviations (RSD) of less than 20%. Cross-validation was performed on the same set of urine samples (n=46) collected from pregnant women residing in the agricultural areas of northern Thailand. The results from split sample analysis from both laboratories agreed well for each metabolite, suggesting that each method can produce

  9. Genomic prediction using different estimation methodology, blending and cross-validation techniques for growth traits and visual scores in Hereford and Braford cattle.

    Science.gov (United States)

    Campos, G S; Reimann, F A; Cardoso, L L; Ferreira, C E R; Junqueira, V S; Schmidt, P I; Braccini Neto, J; Yokoo, M J I; Sollero, B P; Boligon, A A; Cardoso, F F

    2018-05-07

    The objective of the present study was to evaluate the accuracy and bias of direct and blended genomic predictions using different methods and cross-validation techniques for growth traits (weight and weight gains) and visual scores (conformation, precocity, muscling and size) obtained at weaning and at yearling in Hereford and Braford breeds. Phenotypic data contained 126,290 animals belonging to the Delta G Connection genetic improvement program, and a set of 3,545 animals genotyped with the 50K chip and 131 sires with the 777K. After quality control, 41,045 markers remained for all animals. An animal model was used to estimate (co)variances components and to predict breeding values, which were later used to calculate the deregressed estimated breeding values (DEBV). Animals with genotype and phenotype for the traits studied were divided into four or five groups by random and k-means clustering cross-validation strategies. The values of accuracy of the direct genomic values (DGV) were moderate to high magnitude for at weaning and at yearling traits, ranging from 0.19 to 0.45 for the k-means and 0.23 to 0.78 for random clustering among all traits. The greatest gain in relation to the pedigree BLUP (PBLUP) was 9.5% with the BayesB method with both the k-means and the random clustering. Blended genomic value accuracies ranged from 0.19 to 0.56 for k-means and from 0.21 to 0.82 for random clustering. The analyzes using the historical pedigree and phenotypes contributed additional information to calculate the GEBV and in general, the largest gains were for the single-step (ssGBLUP) method in bivariate analyses with a mean increase of 43.00% among all traits measured at weaning and of 46.27% for those evaluated at yearling. The accuracy values for the marker effects estimation methods were lower for k-means clustering, indicating that the training set relationship to the selection candidates is a major factor affecting accuracy of genomic predictions. The gains in

  10. Slips of action and sequential decisions: a cross-validation study of tasks assessing habitual and goal-directed action control

    Directory of Open Access Journals (Sweden)

    Zsuzsika Sjoerds

    2016-12-01

    Full Text Available Instrumental learning and decision-making rely on two parallel systems: a goal-directed and a habitual system. In the past decade, several paradigms have been developed to study these systems in animals and humans by means of e.g. overtraining, devaluation procedures and sequential decision-making. These different paradigms are thought to measure the same constructs, but cross-validation has rarely been investigated. In this study we compared two widely used paradigms that assess aspects of goal-directed and habitual behavior. We correlated parameters from a two-step sequential decision-making task that assesses model-based and model-free learning with a slips-of-action paradigm that assesses the ability to suppress cue-triggered, learnt responses when the outcome has been devalued and is therefore no longer desirable. Model-based control during the two-step task showed a very moderately positive correlation with goal-directed devaluation sensitivity, whereas model-free control did not. Interestingly, parameter estimates of model-based and goal-directed behavior in the two tasks were positively correlated with higher-order cognitive measures (e.g. visual short-term memory. These cognitive measures seemed to (at least partly mediate the association between model-based control during sequential decision-making and goal-directed behavior after instructed devaluation. This study provides moderate support for a common framework to describe the propensity towards goal-directed behavior as measured with two frequently used tasks. However, we have to caution that the amount of shared variance between the goal-directed and model-based system in both tasks was rather low, suggesting that each task does also pick up distinct aspects of goal-directed behavior. Further investigation of the commonalities and differences between the model-free and habit systems as measured with these, and other, tasks is needed. Also, a follow-up cross-validation on the neural

  11. Complications after cardiac implantable electronic device implantations

    DEFF Research Database (Denmark)

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard

    2013-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  12. Infectious endocardial intracardiac defibrillator lead, infectious pericarditis, and delayed constrictive pericarditis

    Directory of Open Access Journals (Sweden)

    Mohsen Mir Mohammad Sadeghi

    2013-01-01

    Full Text Available The usage of Implantable Cardiac Defibrillator (ICD since 1980s is becoming more popular these days. The rate of both, endocarditis and constrictive pericarditis are low but it still needs attention. We are reporting a rare case of ICD endocarditis as a result of toe infection in a diabetic patient. This was followed by infectious pericarditis after device removal by open heart surgery and then delayed constrictive pericarditis.

  13. Utilization of automated external defibrillators installed in commonly used areas of Japanese hospitals

    OpenAIRE

    OHTA, SHOICHI; NAKAO, HIROYUKI; KUSHIMOTO, SHIGEKI; HIRAIDE, ATSUSHI; SAKAMOTO, TETSUYA; NAGAO, KEN; HORI, SHINGO

    2013-01-01

    Objective. Since July 2004, it has become legal in Japan for laypersons to use automated external defibrillators (AEDs). We investigated the effect of AED installation in commonly used areas of Japanese Association for Acute Medicine accredited training (JAAM) hospitals. Methods. In 2008, we sent questionnaires to 419 JAAM hospitals enquiring about the systems, operations, outcome and characteristics of AED usage. Results. Valid responses were received from 271 hospitals (64.7%). A total of 2...

  14. Knowledge and attitudes towards cardiopulmonary resuscitation and defibrillation amongst Asian primary health care physicians

    Directory of Open Access Journals (Sweden)

    Marcus Eh Ong

    2009-11-01

    Full Text Available Marcus Eh Ong1, Susan Yap1, Kim P Chan1, Papia Sultana2, Venkataraman Anantharaman11Department of Emergency Medicine, 2Department of Clinical Research, Singapore General Hospital, SingaporeObjective: To assess the knowledge and attitudes of local primary health care physicians in relation to cardiopulmonary resuscitation (CPR and defibrillation.Methods: We conducted a survey on general practitioners in Singapore by using a self-administered questionnaire that comprised 29 questions.Results: The response rate was 80%, with 60 of 75 physicians completing the questionnaire. The average age of the respondents was 52 years. Sixty percent of them reported that they knew how to operate an automated external defibrillator (AED, and 38% had attended AED training. Only 36% were willing to perform mouth-to-mouth ventilation during CPR, and 53% preferred chest compression-only resuscitation (CCR to standard CPR. We found those aged <50 years were more likely to be trained in basic cardiac life support (BCLS (P < 0.001 and advanced cardiac life support (P = 0.005 or to have ever attended to a patient with cardiac arrest (P = 0.007. Female physicians tended to agree that all clinics should have AEDs (P = 0.005 and support legislation to make AEDs compulsory in clinics (P < 0.001. We also found that a large proportion of physicians who were trained in BCLS (P = 0.006 were willing to perform mouth-to-mouth ventilation.Conclusion: Most local primary care physicians realize the importance of defibrillation, and the majority prefer CCR to standard CPR.Keywords: general practitioners, cardiac arrest, resuscitation, defibrillation, attitude, knowledge

  15. Automated external defibrillation as part BLS: implications for education and practice.

    Science.gov (United States)

    Moule, Pam; Albarran, John W

    2002-09-01

    The latest Adult Basic Life Support (BLS) guidelines support the inclusion of the use of the automated external defibrillator (AED), as part of basic life support (BLS). Emphasis on the provision of early defibrillation as part of BLS acknowledges the importance of this manoeuvre in the successful termination of ventricular fibrillation. The ramifications of such changes for both first responders and organisations implementing the guidelines should not be underestimated. Issues relating to resourcing, content and duration of training and retraining, auditing and evaluation require further exploration. To consider these issues now seems particularly pertinent, given the recent launch of the UK Government's paper on public health, 'Saving Lives-Our Healthier Nation' which seeks to deploy AEDs in busy public places for use by trained members of the lay public. Additionally, defibrillation has been identified as one of the key competencies that all trained nurses and other health care providers should be able to undertake. This paper will consider the background to the current guideline changes, analyse the wider implications of translating the recommendations into practice, and offer possible solutions to address the issues raised. Whilst the analysis is particularly pertinent to the United Kingdom, many of the issues raised have international importance.

  16. Impact of Bystander Automated External Defibrillator Use on Survival and Functional Outcomes in Shockable Observed Public Cardiac Arrests.

    Science.gov (United States)

    Pollack, Ross A; Brown, Siobhan P; Rea, Thomas; Aufderheide, Tom; Barbic, David; Buick, Jason E; Christenson, James; Idris, Ahamed H; Jasti, Jamie; Kampp, Michael; Kudenchuk, Peter; May, Susanne; Muhr, Marc; Nichol, Graham; Ornato, Joseph P; Sopko, George; Vaillancourt, Christian; Morrison, Laurie; Weisfeldt, Myron

    2018-02-26

    Background - Survival following out-of-hospital cardiac arrest (OHCA) with shockable rhythms can be improved with early defibrillation. Although shockable OHCA accounts for only ≈25% of overall arrests, ≈60% of public OHCAs are shockable, offering the possibility of restoring thousands of individuals to full recovery with early defibrillation by bystanders. We sought to determine the association of bystander automated external defibrillator use with survival and functional outcomes in shockable observed public OHCA. Methods - From 2011 to 2015, the Resuscitation Outcomes Consortium prospectively collected detailed information on all cardiac arrests at 9 regional centers. The exposures were shock administration by a bystander-applied automated external defibrillator in comparison with initial defibrillation by emergency medical services. The primary outcome measure was discharge with normal or near-normal (favorable) functional status defined as a modified Rankin Score ≤2. Survival to hospital discharge was the secondary outcome measure. Results -Among 49 555 OHCAs, 4115 (8.3%) observed public OHCAs were analyzed, of which 2500 (60.8%) were shockable. A bystander shock was applied in 18.8% of the shockable arrests. Patients shocked by a bystander were significantly more likely to survive to discharge (66.5% versus 43.0%) and be discharged with favorable functional outcome (57.1% versus 32.7%) than patients initially shocked by emergency medical services. After adjusting for known predictors of outcome, the odds ratio associated with a bystander shock was 2.62 (95% confidence interval, 2.07-3.31) for survival to hospital discharge and 2.73 (95% confidence interval, 2.17-3.44) for discharge with favorable functional outcome. The benefit of bystander shock increased progressively as emergency medical services response time became longer. Conclusions - Bystander automated external defibrillator use before emergency medical services arrival in shockable observed

  17. Sediment transport patterns in the San Francisco Bay Coastal System from cross-validation of bedform asymmetry and modeled residual flux

    Science.gov (United States)

    Barnard, Patrick L.; Erikson, Li H.; Elias, Edwin P.L.; Dartnell, Peter; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    The morphology of ~ 45,000 bedforms from 13 multibeam bathymetry surveys was used as a proxy for identifying net bedload sediment transport directions and pathways throughout the San Francisco Bay estuary and adjacent outer coast. The spatially-averaged shape asymmetry of the bedforms reveals distinct pathways of ebb and flood transport. Additionally, the region-wide, ebb-oriented asymmetry of 5% suggests net seaward-directed transport within the estuarine-coastal system, with significant seaward asymmetry at the mouth of San Francisco Bay (11%), through the northern reaches of the Bay (7–8%), and among the largest bedforms (21% for λ > 50 m). This general indication for the net transport of sand to the open coast strongly suggests that anthropogenic removal of sediment from the estuary, particularly along clearly defined seaward transport pathways, will limit the supply of sand to chronically eroding, open-coast beaches. The bedform asymmetry measurements significantly agree (up to ~ 76%) with modeled annual residual transport directions derived from a hydrodynamically-calibrated numerical model, and the orientation of adjacent, flow-sculpted seafloor features such as mega-flute structures, providing a comprehensive validation of the technique. The methods described in this paper to determine well-defined, cross-validated sediment transport pathways can be applied to estuarine-coastal systems globally where bedforms are present. The results can inform and improve regional sediment management practices to more efficiently utilize often limited sediment resources and mitigate current and future sediment supply-related impacts.

  18. Estimation of influential points in any data set from coefficient of determination and its leave-one-out cross-validated counterpart.

    Science.gov (United States)

    Tóth, Gergely; Bodai, Zsolt; Héberger, Károly

    2013-10-01

    Coefficient of determination (R (2)) and its leave-one-out cross-validated analogue (denoted by Q (2) or R cv (2) ) are the most frequantly published values to characterize the predictive performance of models. In this article we use R (2) and Q (2) in a reversed aspect to determine uncommon points, i.e. influential points in any data sets. The term (1 - Q (2))/(1 - R (2)) corresponds to the ratio of predictive residual sum of squares and the residual sum of squares. The ratio correlates to the number of influential points in experimental and random data sets. We propose an (approximate) F test on (1 - Q (2))/(1 - R (2)) term to quickly pre-estimate the presence of influential points in training sets of models. The test is founded upon the routinely calculated Q (2) and R (2) values and warns the model builders to verify the training set, to perform influence analysis or even to change to robust modeling.

  19. Shuffling cross-validation-bee algorithm as a new descriptor selection method for retention studies of pesticides in biopartitioning micellar chromatography.

    Science.gov (United States)

    Zarei, Kobra; Atabati, Morteza; Ahmadi, Monire

    2017-05-04

    Bee algorithm (BA) is an optimization algorithm inspired by the natural foraging behaviour of honey bees to find the optimal solution which can be proposed to feature selection. In this paper, shuffling cross-validation-BA (CV-BA) was applied to select the best descriptors that could describe the retention factor (log k) in the biopartitioning micellar chromatography (BMC) of 79 heterogeneous pesticides. Six descriptors were obtained using BA and then the selected descriptors were applied for model development using multiple linear regression (MLR). The descriptor selection was also performed using stepwise, genetic algorithm and simulated annealing methods and MLR was applied to model development and then the results were compared with those obtained from shuffling CV-BA. The results showed that shuffling CV-BA can be applied as a powerful descriptor selection method. Support vector machine (SVM) was also applied for model development using six selected descriptors by BA. The obtained statistical results using SVM were better than those obtained using MLR, as the root mean square error (RMSE) and correlation coefficient (R) for whole data set (training and test), using shuffling CV-BA-MLR, were obtained as 0.1863 and 0.9426, respectively, while these amounts for the shuffling CV-BA-SVM method were obtained as 0.0704 and 0.9922, respectively.

  20. Incidência de choques e qualidade de vida em jovens com cardioversor-desfibrilador implantável Incidence of shock and quality of life in young patients with implantable cardioverter-defibrillator

    Directory of Open Access Journals (Sweden)

    Roberto Costa

    2007-03-01

    Full Text Available OBJETIVOS: Avaliar a incidência e a causa de choques de CDI em crianças e adolescentes e sua repercussão na qualidade de vida (QV. MÉTODOS: De março/1997 a fevereiro/2006, 29 pacientes (15,7±5,4 anos foram submetidos a implante de CDI. Parada cardiorrespiratória recuperada (41,5%, taquicardia ventricular sustentada (27,6% e profilaxia primária de morte súbita cardíaca (30,9% motivaram os implantes. O número de terapias foi avaliado por entrevista e pela telemetria dos CDI. A QV foi avaliada pela aplicação do questionário SF-36 e comparada à de indivíduos saudáveis. Empregou-se o método de Kaplan-Meier para análise da sobrevida livre de choques. RESULTADOS: Após 2,6±1,8 anos de seguimento, 8 (27,6% pacientes receberam 141 choques apropriados em razão de TV polimórfica (6 ou FV (2, e 11 (37,9% sofreram 152 choques inapropriados em razão de taquiarritmias supraventriculares (8 ou oversensing (3. A expectativa de sobrevida livre de choques apropriados foi de 74,2%±9,0 após um ano, e de 66,7%±10,7 após três anos. Observou-se diminuição da QV nos aspectos físicos (61,7±28,7, na vitalidade (64,7±19,1, na saúde mental (65,9±22,7 e nos aspectos emocionais (66,7±38,5. Medo e preocupações relacionados ao CDI foram referidos por todos os pacientes. CONCLUSÃO: A despeito da grande eficácia dessa terapêutica, a incidência elevada de choques interferiu na QV e na adaptação ao dispositivo.OBJECTIVES: To analyze the incidence and causes of ICD therapies in children and young adults and verify their impact on the quality of life (QoL. METHODS: From March/1977 to February/2006, 29 patients (15.7±5.4 years old were submitted to ICD implants. Aborted cardiac arrest (41.5%, sustained ventricular tachycardia (27.6% and primary prophylaxis of sudden cardiac death (30.9% indicated device therapy. The number of therapies was evaluated by interviewing patients and by ICD diagnostic data. The SF-36 questionnaire was used to measure the QoL and the results were compared to healthy population. The expectative of freedom from ICD therapies were estimated by the Kaplan-Meier method. RESULTS: After 2.6±1.8 years follow-up, 8 (27.6% patients received 141 appropriate ICD shocks due to ventricular tachycardia (6 or ventricular fibrillation (2, and 11 (37.9% patients received 152 inappropriate ICD shocks due to supraventricular tachyarrhythmias (8 or oversensing (3. Expectative of freedom from appropriate shocks was 74.2±9.0% and 66.7±10.7% after one and three years, respectively. Compared to healthy population, QoL decreased in physical function (61.7±28.7, vitality (64.7±19.1, mental health (65.9±22.7 and role-emotional domains (66.7±38.5. All patients referred fear and concern related to ICD use. CONCLUSION: Despite the efficacy of ICD therapies, the high incidence of appropriate and inappropriate shocks interfered in patients’ QoL and adaptation to the device.

  1. Comparison of low-energy versus high-energy biphasic defibrillation shocks following prolonged ventricular fibrillation.

    Science.gov (United States)

    Walcott, Gregory P; Melnick, Sharon B; Killingsworth, Cheryl R; Ideker, Raymond E

    2010-01-01

    Since the initial development of the defibrillator, there has been concern that, while delivery of a large electric shock would stop fibrillation, it would also cause damage to the heart. This concern has been raised again with the development of the biphasic defibrillator. To compare defibrillation efficacy, postshock cardiac function, and troponin I levels following 150-J and 360-J shocks. Nineteen swine were anesthetized with isoflurane and instrumented with pressure catheters in the left ventricle, aorta, and right atrium. The animals were fibrillated for 6 minutes, followed by defibrillation with either low-energy (n = 8) or high-energy (n = 11) shocks. After defibrillation, chest compressions were initiated and continued until return of spontaneous circulation (ROSC). Epinephrine, 0.01 mg/kg every 3 minutes, was given for arterial blood pressure < 50 mmHg. Hemodynamic parameters were recorded for four hours. Transthoracic echocardiography was performed and troponin I levels were measured at baseline and four hours following ventricular fibrillation (VF). Survival rates at four hours were not different between the two groups (low-energy, 5 of 8; high-energy, 7 of 11). Results for arterial blood pressure, positive dP/dt (first derivative of pressure measured over time, a measure of left ventricular contractility), and negative dP/dt at the time of lowest arterial blood pressure (ABP) following ROSC were not different between the two groups (p = not significant [NS]), but were lower than at baseline. All hemodynamic measures returned to baseline by four hours. Ejection fractions, stroke volumes, and cardiac outputs were not different between the two groups at four hours. Troponin I levels at four hours were not different between the two groups (12 +/- 11 ng/mL versus 21 +/- 26 ng/mL, p = NS) but were higher at four hours than at baseline (19 +/- 19 ng/mL versus 0.8 +/- 0.5 ng/mL, p < 0.05, groups combined). Biphasic 360-J shocks do not cause more cardiac damage

  2. Ranking Businesses and Municipal Locations by Spatiotemporal Cardiac Arrest Risk to Guide Public Defibrillator Placement.

    Science.gov (United States)

    Sun, Christopher L F; Brooks, Steven C; Morrison, Laurie J; Chan, Timothy C Y

    2017-03-21

    Efforts to guide automated external defibrillator placement for out-of-hospital cardiac arrest (OHCA) treatment have focused on identifying broadly defined location categories without considering hours of operation. Broad location categories may be composed of many businesses with varying accessibility. Identifying specific locations for automated external defibrillator deployment incorporating operating hours and time of OHCA occurrence may improve automated external defibrillator accessibility. We aim to identify specific businesses and municipal locations that maximize OHCA coverage on the basis of spatiotemporal assessment of OHCA risk in the immediate vicinity of franchise locations. This study was a retrospective population-based cohort study using data from the Toronto Regional RescuNET Epistry cardiac arrest database. We identified all nontraumatic public OHCAs occurring in Toronto, ON, Canada, from January 2007 through December 2015. We identified 41 unique businesses and municipal location types with ≥20 locations in Toronto from the YellowPages, Canadian Franchise Association, and the City of Toronto Open Data Portal. We obtained their geographic coordinates and hours of operation from Web sites, by phone, or in person. We determined the number of OHCAs that occurred within 100 m of each location when it was open (spatiotemporal coverage) for Toronto overall and downtown. The businesses and municipal locations were then ranked by spatiotemporal OHCA coverage. To evaluate temporal stability of the rankings, we calculated intraclass correlation of the annual coverage values. There were 2654 nontraumatic public OHCAs. Tim Hortons ranked first in Toronto, covering 286 OHCAs. Starbucks ranked first in downtown, covering 110 OHCAs. Coffee shops and bank machines from the 5 largest Canadian banks occupied 8 of the top 10 spots in both Toronto and downtown. The rankings exhibited high temporal stability with intraclass correlation values of 0.88 (95

  3. del Nido versus St. Thomas Cardioplegia Solutions: A Single-Center Retrospective Analysis of Post Cross-Clamp Defibrillation Rates.

    Science.gov (United States)

    Buel, Shane T; Striker, Carrie Whittaker; O'Brien, James E

    2016-06-01

    There are many cardioplegia solutions currently in use for pediatric cardiopulmonary bypass (CPB). The most common being del Nido solution. Another common cardioplegia solution used for pediatric CPB is St. Thomas. In October 2014, Children's Mercy Kansas City changed from the use of modified St. Thomas to del Nido. This study compared rates of post cross-clamp fibrillation requiring defibrillation between del Nido solution and modified St. Thomas solution stratified by weight at Children's Mercy Kansas City. This retrospective study consisted of 394 patients who underwent cardiac surgery requiring cardioplegia between January 1, 2014 and July 31, 2015. The outcome measured was defibrillation upon cross-clamp removal. Statistical significance was determined using Fishers exact test with a two-sided significance level of .05. Incidence of defibrillation post cross-clamp removal was 4.4% in the del Nido group and 26.8% in the St. Thomas group (p Thomas group (p Thomas group (p Thomas group (p 60-kg category had an incidence of defibrillation of 16.7% in the del Nido group and 63% in the St. Thomas group (p Thomas and del Nido cardioplegia solutions. Analyses of weight stratifications demonstrate a decrease in the rate of defibrillation post cross-clamp removal in all categories within the del Nido group.

  4. 41 CFR 102-79.115 - What guidelines must an agency follow if it elects to establish a public access defibrillation...

    Science.gov (United States)

    2010-07-01

    ... SPACE Assignment and Utilization of Space Public Access Defibrillation Programs § 102-79.115 What... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What guidelines must an agency follow if it elects to establish a public access defibrillation program in a Federal facility? 102...

  5. An intercomparison of a large ensemble of statistical downscaling methods for Europe: Overall results from the VALUE perfect predictor cross-validation experiment

    Science.gov (United States)

    Gutiérrez, Jose Manuel; Maraun, Douglas; Widmann, Martin; Huth, Radan; Hertig, Elke; Benestad, Rasmus; Roessler, Ole; Wibig, Joanna; Wilcke, Renate; Kotlarski, Sven

    2016-04-01

    VALUE is an open European network to validate and compare downscaling methods for climate change research (http://www.value-cost.eu). A key deliverable of VALUE is the development of a systematic validation framework to enable the assessment and comparison of both dynamical and statistical downscaling methods. This framework is based on a user-focused validation tree, guiding the selection of relevant validation indices and performance measures for different aspects of the validation (marginal, temporal, spatial, multi-variable). Moreover, several experiments have been designed to isolate specific points in the downscaling procedure where problems may occur (assessment of intrinsic performance, effect of errors inherited from the global models, effect of non-stationarity, etc.). The list of downscaling experiments includes 1) cross-validation with perfect predictors, 2) GCM predictors -aligned with EURO-CORDEX experiment- and 3) pseudo reality predictors (see Maraun et al. 2015, Earth's Future, 3, doi:10.1002/2014EF000259, for more details). The results of these experiments are gathered, validated and publicly distributed through the VALUE validation portal, allowing for a comprehensive community-open downscaling intercomparison study. In this contribution we describe the overall results from Experiment 1), consisting of a European wide 5-fold cross-validation (with consecutive 6-year periods from 1979 to 2008) using predictors from ERA-Interim to downscale precipitation and temperatures (minimum and maximum) over a set of 86 ECA&D stations representative of the main geographical and climatic regions in Europe. As a result of the open call for contribution to this experiment (closed in Dec. 2015), over 40 methods representative of the main approaches (MOS and Perfect Prognosis, PP) and techniques (linear scaling, quantile mapping, analogs, weather typing, linear and generalized regression, weather generators, etc.) were submitted, including information both data

  6. Cross-validation of the Dot Counting Test in a large sample of credible and non-credible patients referred for neuropsychological testing.

    Science.gov (United States)

    McCaul, Courtney; Boone, Kyle B; Ermshar, Annette; Cottingham, Maria; Victor, Tara L; Ziegler, Elizabeth; Zeller, Michelle A; Wright, Matthew

    2018-01-18

    To cross-validate the Dot Counting Test in a large neuropsychological sample. Dot Counting Test scores were compared in credible (n = 142) and non-credible (n = 335) neuropsychology referrals. Non-credible patients scored significantly higher than credible patients on all Dot Counting Test scores. While the original E-score cut-off of ≥17 achieved excellent specificity (96.5%), it was associated with mediocre sensitivity (52.8%). However, the cut-off could be substantially lowered to ≥13.80, while still maintaining adequate specificity (≥90%), and raising sensitivity to 70.0%. Examination of non-credible subgroups revealed that Dot Counting Test sensitivity in feigned mild traumatic brain injury (mTBI) was 55.8%, whereas sensitivity was 90.6% in patients with non-credible cognitive dysfunction in the context of claimed psychosis, and 81.0% in patients with non-credible cognitive performance in depression or severe TBI. Thus, the Dot Counting Test may have a particular role in detection of non-credible cognitive symptoms in claimed psychiatric disorders. Alternative to use of the E-score, failure on ≥1 cut-offs applied to individual Dot Counting Test scores (≥6.0″ for mean grouped dot counting time, ≥10.0″ for mean ungrouped dot counting time, and ≥4 errors), occurred in 11.3% of the credible sample, while nearly two-thirds (63.6%) of the non-credible sample failed one of more of these cut-offs. An E-score cut-off of 13.80, or failure on ≥1 individual score cut-offs, resulted in few false positive identifications in credible patients, and achieved high sensitivity (64.0-70.0%), and therefore appear appropriate for use in identifying neurocognitive performance invalidity.

  7. WE-DE-201-04: Cross Validation of Knowledge-Based Treatment Planning for Prostate LDR Brachytherapy Using Principle Component Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Roper, J; Ghavidel, B; Godette, K; Schreibmann, E [Winship Cancer Institute of Emory University, GA (United States); Chanyavanich, V [Rocky Mountain Cancer Centers, CO (United States)

    2016-06-15

    Purpose: To validate a knowledge-based algorithm for prostate LDR brachytherapy treatment planning. Methods: A dataset of 100 cases was compiled from an active prostate seed implant service. Cases were randomized into 10 subsets. For each subset, the 90 remaining library cases were registered to a common reference frame and then characterized on a point by point basis using principle component analysis (PCA). Each test case was converted to PCA vectors using the same process and compared with each library case using a Mahalanobis distance to evaluate similarity. Rank order PCA scores were used to select the best-matched library case. The seed arrangement was extracted from the best-matched case and used as a starting point for planning the test case. Any subsequent modifications were recorded that required input from a treatment planner to achieve V100>95%, V150<60%, V200<20%. To simulate operating-room planning constraints, seed activity was held constant, and the seed count could not increase. Results: The computational time required to register test-case contours and evaluate PCA similarity across the library was 10s. Preliminary analysis of 2 subsets shows that 9 of 20 test cases did not require any seed modifications to obtain an acceptable plan. Five test cases required fewer than 10 seed modifications or a grid shift. Another 5 test cases required approximately 20 seed modifications. An acceptable plan was not achieved for 1 outlier, which was substantially larger than its best match. Modifications took between 5s and 6min. Conclusion: A knowledge-based treatment planning algorithm for prostate LDR brachytherapy is being cross validated using 100 prior cases. Preliminary results suggest that for this size library, acceptable plans can be achieved without planner input in about half of the cases while varying amounts of planner input are needed in remaining cases. Computational time and planning time are compatible with clinical practice.

  8. A model of prediction and cross-validation of fat-free mass in men with motor complete spinal cord injury.

    Science.gov (United States)

    Gorgey, Ashraf S; Dolbow, David R; Gater, David R

    2012-07-01

    To establish and validate prediction equations by using body weight to predict legs, trunk, and whole-body fat-free mass (FFM) in men with chronic complete spinal cord injury (SCI). Cross-sectional design. Research setting in a large medical center. Individuals with SCI (N=63) divided into prediction (n=42) and cross-validation (n=21) groups. Not applicable. Whole-body FFM and regional FFM were determined by using dual-energy x-ray absorptiometry. Body weight was measured by using a wheelchair weighing scale after subtracting the weight of the chair. Body weight predicted legs FFM (legs FFM=.09×body weight+6.1; R(2)=.25, standard error of the estimate [SEE]=3.1kg, PFFM (trunk FFM=.21×body weight+8.6; R(2)=.56, SEE=3.6kg, PFFM (whole-body FFM=.288×body weight+26.3; R(2)=.53, SEE=5.3kg, PFFM(predicted) (FFM predicted from the derived equations) shared 86% of the variance in whole-body FFM(measured) (FFM measured using dual-energy x-ray absorptiometry scan) (R(2)=.86, SEE=1.8kg, PFFM(measured), and 66% of legs FFM(measured). The trunk FFM(predicted) shared 69% of the variance in trunk FFM(measured) (R(2)=.69, SEE=2.7kg, PFFM(predicted) shared 67% of the variance in legs FFM(measured) (R(2)=.67, SEE=2.8kg, PFFM did not differ between the prediction and validation groups. Body weight can be used to predict whole-body FFM and regional FFM. The predicted whole-body FFM improved the prediction of trunk FFM and legs FFM. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  9. Evolution of Precipitation Structure During the November DYNAMO MJO Event: Cloud-Resolving Model Intercomparison and Cross Validation Using Radar Observations

    Science.gov (United States)

    Li, Xiaowen; Janiga, Matthew A.; Wang, Shuguang; Tao, Wei-Kuo; Rowe, Angela; Xu, Weixin; Liu, Chuntao; Matsui, Toshihisa; Zhang, Chidong

    2018-04-01

    Evolution of precipitation structures are simulated and compared with radar observations for the November Madden-Julian Oscillation (MJO) event during the DYNAmics of the MJO (DYNAMO) field campaign. Three ground-based, ship-borne, and spaceborne precipitation radars and three cloud-resolving models (CRMs) driven by observed large-scale forcing are used to study precipitation structures at different locations over the central equatorial Indian Ocean. Convective strength is represented by 0-dBZ echo-top heights, and convective organization by contiguous 17-dBZ areas. The multi-radar and multi-model framework allows for more stringent model validations. The emphasis is on testing models' ability to simulate subtle differences observed at different radar sites when the MJO event passed through. The results show that CRMs forced by site-specific large-scale forcing can reproduce not only common features in cloud populations but also subtle variations observed by different radars. The comparisons also revealed common deficiencies in CRM simulations where they underestimate radar echo-top heights for the strongest convection within large, organized precipitation features. Cross validations with multiple radars and models also enable quantitative comparisons in CRM sensitivity studies using different large-scale forcing, microphysical schemes and parameters, resolutions, and domain sizes. In terms of radar echo-top height temporal variations, many model sensitivity tests have better correlations than radar/model comparisons, indicating robustness in model performance on this aspect. It is further shown that well-validated model simulations could be used to constrain uncertainties in observed echo-top heights when the low-resolution surveillance scanning strategy is used.

  10. Higher risks when working unusual times? A cross-validation of the effects on safety, health, and work-life balance.

    Science.gov (United States)

    Greubel, Jana; Arlinghaus, Anna; Nachreiner, Friedhelm; Lombardi, David A

    2016-11-01

    Replication and cross-validation of results on health and safety risks of work at unusual times. Data from two independent surveys (European Working Conditions Surveys 2005 and 2010; EU 2005: n = 23,934 and EU 2010: n = 35,187) were used to examine the relative risks of working at unusual times (evenings, Saturdays, and Sundays) on work-life balance, work-related health complaints, and occupational accidents using logistic regression while controlling for potential confounders such as demographics, work load, and shift work. For the EU 2005 survey, evening work was significantly associated with an increased risk of poor work-life balance (OR 1.69) and work-related health complaints (OR 1.14), Saturday work with poor work-life balance (OR 1.49) and occupational accidents (OR 1.34), and Sunday work with poor work-life balance (OR 1.15) and work-related health complaints (OR 1.17). For EU 2010, evening work was associated with poor work-life balance (OR 1.51) and work-related health complaints (OR 1.12), Saturday work with poor work-life balance (OR 1.60) and occupational accidents (OR 1.19) but a decrease in risk for work-related health complaints (OR 0.86) and Sunday work with work-related health complaints (OR 1.13). Risk estimates in both samples yielded largely similar results with comparable ORs and overlapping confidence intervals. Work at unusual times constitutes a considerable risk to social participation and health and showed structurally consistent effects over time and across samples.

  11. A cross-validation trial of an Internet-based prevention program for alcohol and cannabis: Preliminary results from a cluster randomised controlled trial.

    Science.gov (United States)

    Champion, Katrina E; Newton, Nicola C; Stapinski, Lexine; Slade, Tim; Barrett, Emma L; Teesson, Maree

    2016-01-01

    Replication is an important step in evaluating evidence-based preventive interventions and is crucial for establishing the generalizability and wider impact of a program. Despite this, few replications have occurred in the prevention science field. This study aims to fill this gap by conducting a cross-validation trial of the Climate Schools: Alcohol and Cannabis course, an Internet-based prevention program, among a new cohort of Australian students. A cluster randomized controlled trial was conducted among 1103 students (Mage: 13.25 years) from 13 schools in Australia in 2012. Six schools received the Climate Schools course and 7 schools were randomized to a control group (health education as usual). All students completed a self-report survey at baseline and immediately post-intervention. Mixed-effects regressions were conducted for all outcome variables. Outcomes assessed included alcohol and cannabis use, knowledge and intentions to use these substances. Compared to the control group, immediately post-intervention the intervention group reported significantly greater alcohol (d = 0.67) and cannabis knowledge (d = 0.72), were less likely to have consumed any alcohol (even a sip or taste) in the past 6 months (odds ratio = 0.69) and were less likely to intend on using alcohol in the future (odds ratio = 0.62). However, there were no effects for binge drinking, cannabis use or intentions to use cannabis. These preliminary results provide some support for the Internet-based Climate Schools: Alcohol and Cannabis course as a feasible way of delivering alcohol and cannabis prevention. Intervention effects for alcohol and cannabis knowledge were consistent with results from the original trial; however, analyses of longer-term follow-up data are needed to provide a clearer indication of the efficacy of the intervention, particularly in relation to behavioral changes. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  12. Do clinical examination gloves provide adequate electrical insulation for safe hands-on defibrillation? I: Resistive properties of nitrile gloves.

    Science.gov (United States)

    Deakin, Charles D; Lee-Shrewsbury, Victoria; Hogg, Kitwani; Petley, Graham W

    2013-07-01

    Uninterrupted chest compressions are a key factor in determining resuscitation success. Interruptions to chest compression are often associated with defibrillation, particularly the need to stand clear from the patient during defibrillation. It has been suggested that clinical examination gloves may provide adequate electrical resistance to enable safe hands-on defibrillation in order to minimise interruptions. We therefore examined whether commonly used nitrile clinical examination gloves provide adequate resistance to current flow to enable safe hands-on defibrillation. Clinical examination gloves (Kimberly Clark KC300 Sterling nitrile) worn by members of hospital cardiac arrest teams were collected immediately following termination of resuscitation. To determine the level of protection afforded by visually intact gloves, electrical resistance across the glove was measured by applying a DC voltage across the glove and measuring subsequent resistance. Forty new unused gloves (control) were compared with 28 clinical (non-CPR) gloves and 128 clinical (CPR) gloves. One glove in each group had a visible tear and was excluded from analysis. Control gloves had a minimum resistance of 120 kΩ (median 190 kΩ) compared with 60 kΩ in clinical gloves (both CPR (median 140 kΩ) and non-CPR groups (median 160 kΩ)). Nitrile clinical examination gloves do not provide adequate electrical insulation for the rescuer to safely undertake 'hands-on' defibrillation and when exposed to the physical forces of external chest compression, even greater resistive degradation occurs. Further work is required to identify gloves suitable for safe use for 'hands-on' defibrillation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Early Outcomes of Out-of-Hospital Cardiac Arrest after Early Defibrillation: a 24 Months Retrospective Analysis

    Directory of Open Access Journals (Sweden)

    Paolo Terranova

    2006-10-01

    Full Text Available Introduction: Cardiovascular disease remains the most common cause of death in the United States and most other Western nations. Among these deaths, sudden, out-of-hospital cardiac arrest claims approximately 1000 lives each day in the United States alone. Most of these cardiac arrests are due to ventricular fibrillation. Though highly reversible with the rapid application of a defibrillator, ventricular fibrillation is otherwise fatal within minutes, even when cardiopulmonary resuscitation is provided immediately. The overall survival rate in the United States is estimated to be less than 5 percent. Recent developments in automated-external-defibrillator technology have provided a means of increasing the rate of prompt defibrillation after out-of-hospital cardiac arrest. After minimal training, nonmedical personnel (e.g., flight attendants and casino workers are also able to use defibrillators in the workplace, with lifesaving effects. Nonetheless, such programs have involved designated personnel whose job description includes assisting persons who have had sudden cardiac arrest. Data are still lacking on the success of programs in which automated external defibrillators have been installed in public places to be used by persons who have no specific training or duty to act. Materials and Methods: All patients who had an out-of-hospital cardiac arrest between January 2003 and December 2004 and who received early defibrillation for ventricular fibrillation were included. We conducted a 24 months retrospective population-based analysis of the outcome in our population. Results: Over a 24 month period, 446 people had non–traumatic cardiac arrest, and in all of them it was observed to be ventricular fibrillation. In a very few cases, the defibrillator operators were good Samaritans, acting voluntarily. Eighty-nine patients (about 19% with ventricular fibrillation were successfully resuscitated, including eighteen who regained consciousness before

  14. Manuell arytmitolkning och defibrillering prehospitalt för att minska avbrott i bröstkompressioner

    OpenAIRE

    Mattsson, Andreas; Erling, Kristofer

    2014-01-01

    Abstract Background Todays guidelines for advanced CPR emphasize chest compressions with good quality and early defibrillation. Prehospital CPR performed by ambulance crew, an automated external defibrillator (AED) is used. The AED analyzes the heart rhythm and the performer is following the advice to chock the heart or not, given by the AED. During on-going CPR there are sequences when no chest compression is performed known as hands-off time. Hands-off time includes the time for the AED to ...

  15. Saving lives with public access defibrillation: A deadly game of hide and seek.

    Science.gov (United States)

    Sidebottom, David B; Potter, Ryan; Newitt, Laura K; Hodgetts, Gillian A; Deakin, Charles D

    2018-07-01

    Early defibrillation is a critical link in the chain of survival. Public access defibrillation (PAD) programmes utilising automated external defibrillators (AEDs) aim to decrease the time-to-first-shock, and improve survival from out-of-hospital cardiac arrest. Effective use of PADs requires rapid location of the device, facilitated by adequate signage. We aimed to therefore assess the quality of signage for PADs in the community. From April 2017 to January 2018 we surveyed community PADs available for public use on the 'Save a Life' AED locator mobile application in and around Southampton, UK. Location and signage characteristics were collected, and the distance from the furthest sign to the AED was measured. Researchers evaluated 201 separate PADs. All devices visited were included in the final analysis. No signage at all was present for 135 (67.2%) devices. Only 15/201 (7.5%) AEDs had signage at a distance from AED itself. In only 5 of these cases (2.5%) was signage mounted more than 5.0 m from the AED. When signage was present, 46 used 2008 ILCOR signage and 15 used 2006 Resuscitation Council (UK) signage. Signage visibility was partially or severely obstructed at 27/66 (40.9%) sites. None of the 45 GP surgeries surveyed used exterior signage or an exterior 24/7 access box. Current signage of PADs is poor and limits the device effectiveness by impeding public awareness and location of AEDs. Recommendations should promote visible signage within the operational radius of each AED. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Underutilisation of public access defibrillation is related to retrieval distance and time-dependent availability.

    Science.gov (United States)

    Deakin, Charles D; Anfield, Steve; Hodgetts, Gillian A

    2018-05-14

    Public access defibrillation doubles the chances of neurologically intact survival following out-of-hospital cardiac arrest (OHCA). Although there are increasing numbers of defibrillators (automated external defibrillator (AEDs)) available in the community, they are used infrequently, despite often being available. We aimed to match OHCAs with known AED locations in order to understand AED availability, the effects of reduced AED availability at night and the operational radius at which they can be effectively retrieved. All emergency calls to South Central Ambulance Service from April 2014 to April 2016 were screened to identify cardiac arrests. Each was mapped to the nearest AED, according to the time of day. Mapping software was used to calculate the actual walking distance for a bystander between each OHCA and respective AED, when travelling at a brisk walking speed (4 mph). 4012 cardiac arrests were identified and mapped to one of 2076 AEDs. All AEDs were available during daytime hours, but only 713 at night (34.3%). 5.91% of cardiac arrests were within a retrieval (walking) radius of 100 m during the day, falling to 1.59% out-of-hours. Distances to rural AEDs were greater than in urban areas (P<0.0001). An AED could potentially have been retrieved prior to actual ambulance arrival in 25.3% cases. Existing AEDs are underused; 36.4% of OHCAs are located within 500 m of an AED. Although more AEDs will improve availability, greater use can be made of existing AEDs, particularly by ensuring they are all available on a 24/7 basis. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  17. Successful Treatment of Refractory Electrical Storm With Landiolol After More Than 100 Electrical Defibrillations.

    Science.gov (United States)

    Kanamori, Kenta; Aoyagi, Takashi; Mikamo, Takashi; Tsutsui, Kenta; Kunishima, Tomoyuki; Inaba, Hideko; Hayami, Noriyuki; Murakawa, Yuji

    2015-01-01

    Electrical storm (ES) was observed in an 82-year-old man with recent myocardial infarction. Conventional therapy, including amiodarone, could not suppress the ES. After more than 100 electrical defibrillations, we were finally able to control the ES with the administration of landiolol. It is known that landiolol can inhibit ES. However, we hesitate to use landiolol in patients with low cardiac output. We would like to emphasize that careful use of landiolol should be considered in patients with refractory ES after myocardial infarction, although cardiac output is severely reduced.

  18. TED-Time and life saving External Defibrillator for home-use.

    Science.gov (United States)

    Weiss, Teddy A; Rosenheck, Shimon; Gorni, Shraga; Katz, Ioni; Mendelbaum, Mendel; Gilon, Dan

    2014-06-01

    Sudden Cardiac Death--SCD --is a major unmet health problem that needs urgent and prompt solution. AICDs are very expensive, risky and indicated for a small group of patients, at the highest risk. AEDs--Automatic External Defibrillators--are designed for public places and although safe, cannot enter the home-market due to their cost and need for constant, high-cost maintenance. We developed TED, a low-cost AED that derives its energy off the mains, designed for home-use, to save SCD victims' lives. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Association of psychiatric history and type D personality with symptoms of anxiety, depression, and health status prior to ICD implantation

    DEFF Research Database (Denmark)

    Starrenburg, Annemieke H; Kraaier, Karin; Pedersen, Susanne S.

    2013-01-01

    Personality factors and psychiatric history may help explain individual differences in risk of psychological morbidity and poor health outcomes in patients with an implantable cardioverter defibrillator (ICD).......Personality factors and psychiatric history may help explain individual differences in risk of psychological morbidity and poor health outcomes in patients with an implantable cardioverter defibrillator (ICD)....

  20. Transmural recording of shock potential gradient fields, early postshock activations, and refibrillation episodes associated with external defibrillation of long-duration ventricular fibrillation in swine.

    Science.gov (United States)

    Allred, James D; Killingsworth, Cheryl R; Allison, J Scott; Dosdall, Derek J; Melnick, Sharon B; Smith, William M; Ideker, Raymond E; Walcott, Gregory P

    2008-11-01

    Knowledge of the shock potential gradient (nablaV) and postshock activation is limited to internal defibrillation of short-duration ventricular fibrillation (SDVF). The purpose of this study was to determine these variables after external defibrillation of long-duration VF (LDVF). In six pigs, 115-20 plunge needles with three to six electrodes each were inserted to record throughout both ventricles. After the chest was closed, the biphasic defibrillation threshold (DFT) was determined after 20 seconds of SDVF with external defibrillation pads. After 7 minutes of LDVF, defibrillation shocks that were less than or equal to the SDVF DFT strength were given. For DFT shocks (1632 +/- 429 V), the maximum minus minimum ventricular voltage (160 +/- 100 V) was 9.8% of the shock voltage. Maximum cardiac nablaV (28.7 +/- 17 V/cm) was 4.7 +/- 2.0 times the minimum nablaV (6.2 +/- 3.5 V/cm). Although LDVF did not increase the DFT in five of the six pigs, it significantly lengthened the time to earliest postshock activation following defibrillation (1.6 +/- 2.2 seconds for SDVF and 4.9 +/- 4.3 seconds for LDVF). After LDVF, 1.3 +/- 0.8 episodes of spontaneous refibrillation occurred per animal, but there was no refibrillation after SDVF. Compared with previous studies of internal defibrillation, during external defibrillation much less of the shock voltage appears across the heart and the shock field is much more even; however, the minimum nablaV is similar. Compared with external defibrillation of SDVF, the biphasic external DFT for LDVF is not increased; however, time to earliest postshock activation triples. Refibrillation is common after LDVF but not after SDVF in these normal hearts, indicating that LDVF by itself can cause refibrillation without requiring preexisting heart disease.

  1. Computational cardiology: the bidomain based modified Hill model incorporating viscous effects for cardiac defibrillation

    Science.gov (United States)

    Cansız, Barış; Dal, Hüsnü; Kaliske, Michael

    2017-10-01

    Working mechanisms of the cardiac defibrillation are still in debate due to the limited experimental facilities and one-third of patients even do not respond to cardiac resynchronization therapy. With an aim to develop a milestone towards reaching the unrevealed mechanisms of the defibrillation phenomenon, we propose a bidomain based finite element formulation of cardiac electromechanics by taking into account the viscous effects that are disregarded by many researchers. To do so, the material is deemed as an electro-visco-active material and described by the modified Hill model (Cansız et al. in Comput Methods Appl Mech Eng 315:434-466, 2017). On the numerical side, we utilize a staggered solution method, where the elliptic and parabolic part of the bidomain equations and the mechanical field are solved sequentially. The comparative simulations designate that the viscoelastic and elastic formulations lead to remarkably different outcomes upon an externally applied electric field to the myocardial tissue. Besides, the achieved framework requires significantly less computational time and memory compared to monolithic schemes without loss of stability for the presented examples.

  2. Is there an Optimal Shape of the Defibrillation Shock: Constant Current vs. Pulsed Biphasic Waveforms

    Directory of Open Access Journals (Sweden)

    Ivan Dotsinsky

    2013-04-01

    Full Text Available Three waveforms for transthoracic defibrillation are assessed and compared: the Pulsed Biphasic Waveform (PBW, the Rectilinear Biphasic Waveform (RBW, and the "lossless" constant current (LLCC pulses. Two indices are introduced: 1 kf = W/W0 - the ratio between the delivered energy W and the energy W0 of a rectangular pulse with the same duration and electric charge; 2 ηC = W/WC0 - the level of utilizing the initially loaded capacitor energy WC0. The envisioned comparative study shows that ηC index is favorable for both PBW and LLCC, while kf of both RBW and LLCC demonstrates advantage over the PBW in the range of small inter-electrode thoracic impedances below 80 Ω. Some design considerations are also discussed. The attractive LLCC concept needs large and heavy inductive coil to support the constant current amplitude, besides it is capable to induce strong electromagnetic influences due to the complex current control. The RBW technology controls the delivery of current through a series of internal resistors which are, however, a source of high heat losses. The PBW implements controlled duty cycle of high-frequency chopped pulses to adapt the energy delivery in respect of the patient impedance measured at the beginning of the shock. PBW technology makes use of small capacitors which allows the construction of light weight and small-size portable devices for transthoracic defibrillation.

  3. Bystander Automated External Defibrillator Use and Clinical Outcomes after Out-of-Hospital Cardiac Arrest

    DEFF Research Database (Denmark)

    Holmberg, Mathias J; Vognsen, Mikael; Andersen, Mikkel S

    2017-01-01

    Aim: To systematically review studies comparing bystander automated external defibrillator (AED) use to no AED use in regard to clinical outcomes in out-of-hospital cardiac arrest (OHCA), and to provide a descriptive summary of studies on the cost-effectiveness of bystander AED use. Methods: We...... randomized trials, and 13 cost-effectiveness studies were included. Meta-analysis of 6 observational studies without critical risk of bias showed that bystander AED use was associated with survival to hospital discharge (all rhythms OR: 1.73 [95% CI: 1.36, 2.18], shockable rhythms OR: 1.66 [95% CI: 1.54, 1.......79]) and favorable neurological outcome (all rhythms OR: 2.12 [95% CI: 1.36, 3.29], shockable rhythms OR: 2.37 [95% CI: 1.58, 3.57]). There was no association between bystander AED use and neurological outcome for non-shockable rhythms (OR: 0.76 [95% CI: 0.10, 5.87]). The Public-Access Defibrillation trial found...

  4. Surviving out-of-hospital cardiac arrest: just a matter of defibrillators?

    Science.gov (United States)

    Zorzi, Alessandro; Gasparetto, Nicola; Stella, Federica; Bortoluzzi, Andrea; Cacciavillani, Luisa; Basso, Cristina

    2014-08-01

    Out-of-hospital sudden cardiac arrest (OHCA) is a leading cause of death all over the world. Although the outcome of OHCA resulting from 'nonshockable' rhythms (asystole and pulseless electrical activity) is poor regardless of resuscitation efforts, 'shockable' rhythms such as ventricular tachycardia or fibrillation may carry a good prognosis if early defibrillation is performed. At present, simplified cardiopulmonary resuscitation techniques (hands-only cardiopulmonary resuscitation) and automated external defibrillators (AEDs) offer lay people the possibility to provide lifesaving treatment to OHCA victims in the critical minutes before the arrival of the emergency medical system. Programs aimed at increasing provision of cardiopulmonary resuscitation and use of AEDs by lay people have been set up in different countries, including Italy, and have contributed to improve survival rates. However, success of these programs critically depends on appropriate planning and design, and on cultural predisposition of witnesses to undertake immediate measures of resuscitation in the case of OHCA. Placement of a large number of AEDs may carry high costs and little benefits if it is uncoordinated and not preceded by educational campaigns to spread widely the 'culture of resuscitation' in the population.

  5. Automated external defibrillators in the hospital: A case of medical reversal.

    Science.gov (United States)

    Stewart, John A

    2018-05-01

    Automated external defibrillators (AEDs) emerged in the 1980s as an important innovation in pre-hospital emergency cardiac care (ECC). In the years since, the American Heart Association (AHA) and the International Liaison Committee for Resuscitation (ILCOR) have promoted AED technology for use in hospitals as well, resulting in the widespread purchase and use of AED-capable defibrillators. In-hospital use of AEDs now appears to have decreased survival from cardiac arrests. This article will look at the use of AEDs in hospitals as a case of "medical reversal." Medical reversal occurs when an accepted, widely used treatment is found to be ineffective or even harmful. This article will discuss the issue of AEDs in the hospital using a conceptual framework provided by recent work on medical reversal. It will go on to consider the implications of the reversal for in-hospital resuscitation programs and emergency medicine more generally. Copyright © 2017 The Author. Published by Elsevier Inc. All rights reserved.

  6. Subclavian Vein Stenosis/Occlusion Following Transvenous Cardiac Pacemaker and Defibrillator Implantation: Incidence, Pathophysiology and Current Management

    Directory of Open Access Journals (Sweden)

    Brian O'Leary

    2015-08-01

    Full Text Available Subclavian vein stenosis is a common, but usually asymptomatic, complication following cardiac device placement. In addition to reviewing the literature on incidence, pathogenesis and management options for this important clinical problem, we describe two cases of symptomatic subclavian vein occlusion following pacemaker/defibrillator placement and successful treatment with venoplasty and stenting.

  7. Survival and health care costs until hospital discharge of patients treated with onsite, dispatched or without automated external defibrillator

    NARCIS (Netherlands)

    Berdowski, Jocelyn; Kuiper, Mathijs J.; Dijkgraaf, Marcel G. W.; Tijssen, Jan G. P.; Koster, Rudolph W.

    2010-01-01

    Background: This study aimed to determine whether automated external defibrillator (AED) use during resuscitation is associated with lower in-hospital health care costs. Methods: For this observational prospective study, we included all treated out-of-hospital cardiac arrests of suspected cardiac

  8. Mobile Versus Fixed Deployment of Automated External Defibrillators in Rural EMS.

    Science.gov (United States)

    Nelson, R Darrell; Bozeman, William; Collins, Greg; Booe, Brian; Baker, Todd; Alson, Roy

    2015-04-01

    There is no consensus on where automated external defibrillators (AEDs) should be placed in rural communities to maximize impact on survival from cardiac arrest. In the community of Stokes County, North Carolina (USA) the Emergency Medical Services (EMS) system promotes cardiopulmonary resuscitation (CPR) public education and AED use with public access defibrillators (PADs) placed mainly in public schools, churches, and government buildings. This study tested the utilization of AEDs assigned to first responders (FRs) in their private-owned-vehicle (POV) compared to AEDs in fixed locations. The authors performed a prospective, observational study measuring utilization of AEDs carried by FRs in their POV compared to utilization of AEDs in fixed locations. Automated external defibrillator utilization is activation with pads placed on the patient and analysis of heart rhythm to determine if shock/no-shock is indicated. The Institutional Review Board of Wake Forest University Baptist Health System approved the study and written informed consent was waived. The study began on December 01, 2012 at midnight and ended on December 01, 2013 at midnight. During the 12-month study period, 81 community AEDs were in place, 66 in fixed locations and 15 assigned to FRs in their POVs. No utilizations of the 66 fixed location AEDs were reported (0.0 utilizations/AED/year) while 19 utilizations occurred in the FR POV AED study group (1.27 utilizations/AED/year; P<.0001). Odds ratio of using a FR POV located AED was 172 times more likely than using a community fixed-location AED in this rural community. Discussion Placing AEDs in a rural community poses many challenges for optimal utilization in terms of cardiac arrest occurrences. Few studies exist to direct rural community efforts in placing AEDs where they can be most effective, and it has been postulated that placing them directly with FRs may be advantageous. In this rural community, the authors found that placing AED devices with

  9. Cardiac Resynchronization Therapy Defibrillator Treatment in a Child with Heart Failure and Ventricular Arrhythmia

    Directory of Open Access Journals (Sweden)

    Hak Ju Kim

    2016-08-01

    Full Text Available Cardiac resynchronization therapy (CRT is a new treatment for refractory heart failure. However, most patients with heart failure treated with CRT are adults, middle-aged or older with idiopathic or ischemic dilated cardiomyopathy. We treated a 12-year-old boy, who was transferred after cardiac arrest, with dilated cardiomyopathy, left bundle-branch block, and ventricular tachycardia. We performed cardiac resynchronization therapy with a defibrillator (CRT-D. After CRT-D, left ventricular ejection fraction improved from 22% to 4 4% a ssessed by e chocardiog ram 1 year p ostoperatively. On e lectrocardiog ram, Q RS d uration was shortened from 206 to 144 ms. The patient’s clinical symptoms also improved. For pediatric patients with refractory heart failure and ventricular arrhythmia, CRT-D could be indicated as an effective therapeutic option.

  10. Echocardiography in patients with complications related to pacemakers and cardiac defibrillators.

    Science.gov (United States)

    Almomani, Ahmed; Siddiqui, Khadija; Ahmad, Masood

    2014-03-01

    The evolving indications and uses for implantable cardiac devices have led to a significant increase in the number of implanted devices each year. Implantation of endocardial leads for permanent pacemakers and cardiac defibrillators can cause many delayed complications. Complications may be mechanical and related to the interaction of the device leads with the valves and endomyocardium, e.g., perforation, infection, and thrombosis, or due to the electrical pacing of the myocardium and conduction abnormalities, e.g., left ventricular dyssynchrony. Tricuspid regurgitation, another delayed complication in these patients, may be secondary to both mechanical and pacing effects of the device leads. Echocardiography plays an important role in the diagnosis of these device-related complications. Both two-dimensional transthoracic echocardiography and transesophageal echocardiography provide useful diagnostic information. Real time three-dimensional echocardiography is a novel technique that can further enhance the detection of lead-related complications. © 2013, Wiley Periodicals, Inc.

  11. Lay bystanders' perspectives on what facilitates cardiopulmonary resuscitation and use of automated external defibrillators in real cardiac arrests

    DEFF Research Database (Denmark)

    Malta Hansen, Carolina; Rosenkranz, Simone Mørk; Folke, Fredrik

    2017-01-01

    is crucial in improving survival, cannot cause substantial harm, and that the AED will provide guidance through CPR; prior hands-on training in AED use; during CPR performance, teamwork (ie, support), using the AED voice prompt and a ventilation mask, as well as demonstrating leadership and feeling a moral......BACKGROUND: Many patients who suffer an out-of-hospital cardiac arrest will fail to receive bystander intervention (cardiopulmonary resuscitation [CPR] or defibrillation) despite widespread CPR training and the dissemination of automated external defibrillators (AEDs). We sought to investigate what......, until data saturation. We used cross-sectional indexing (using software), and inductive in-depth thematic analyses, to identify those factors that facilitated CPR and AED use. In addition to prior hands-on CPR training, the following were described as facilitators: prior knowledge that intervention...

  12. Location of cardiac arrest in a city center: strategic placement of automated external defibrillators in public locations

    DEFF Research Database (Denmark)

    Folke, Fredrik; Lippert, Freddy Knudsen; Nielsen, Søren Loumann

    2009-01-01

    BACKGROUND: Public-access defibrillation with automated external defibrillators (AEDs) is being implemented in many countries worldwide with considerable financial implications. The potential benefit and economic consequences of focused or unfocused AED deployment are unknown. METHODS AND RESULTS......: All cardiac arrests in public in Copenhagen, Denmark, from 1994 through 2005 were geographically located, as were 104 public AEDs placed by local initiatives. In accordance with European Resuscitation Council and American Heart Association (AHA) guidelines, areas with a high incidence of cardiac...... arrests were defined as those with 1 cardiac arrest every 2 or 5 years, respectively. There were 1274 cardiac arrests in public locations. According to the European Resuscitation Council or AHA guidelines, AEDs needed to be deployed in 1.2% and 10.6% of the city area, providing coverage for 19.5% (n=249...

  13. Lay Bystanders' Perspectives on What Facilitates Cardiopulmonary Resuscitation and Use of Automated External Defibrillators in Real Cardiac Arrests

    DEFF Research Database (Denmark)

    Malta Hansen, Carolina; Rosenkranz, Simone Mørk; Folke, Fredrik

    2017-01-01

    BACKGROUND: Many patients who suffer an out-of-hospital cardiac arrest will fail to receive bystander intervention (cardiopulmonary resuscitation [CPR] or defibrillation) despite widespread CPR training and the dissemination of automated external defibrillators (AEDs). We sought to investigate what...... factors encourage lay bystanders to initiate CPR and AED use in a cohort of bystanders previously trained in CPR techniques who were present at an out-of-hospital cardiac arrest. METHODS AND RESULTS: One-hundred and twenty-eight semistructured qualitative interviews with CPR-trained lay bystanders...... to consecutive out-of-hospital cardiac arrest, where an AED was present were conducted (from January 2012 to April 2015, in Denmark). Purposive maximum variation sampling was used to establish the breadth of the bystander perspective. Twenty-six of the 128 interviews were chosen for further in-depth analyses...

  14. Using left-ventricular-only pacing to eliminate T-wave oversensing in a biventricular implantable cardiac defibrillator.

    Science.gov (United States)

    Khoo, Clarence; Bennett, Matthew; Chakrabarti, Santabhanu; LeMaitre, John; Tung, Stanley K K

    2013-02-01

    A man aged 75 years and with nonischemic cardiomyopathy had implantation of a biventricular implantable cardiac defibrillator (ICD). Consistent biventricular pacing was limited by intermittent T-wave oversensing (TWOS). A strategy of left-ventricular-only pacing was used to eliminate TWOS. This strategy obviates the need to reduce ventricular sensitivity and thus may be an effective alternative to biventricular pacing complicated by TWOS. Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  15. [Ethics in intensive care and euthanasia : With respect to inactivating defibrillators at the end of life in terminally ill patients].

    Science.gov (United States)

    Trappe, H-J

    2017-04-01

    In critically ill patients, intensive care medical procedures allow diseases to be cured or controlled that were considered incurable many years ago. For patients with terminal heart failure or heart disease with other severe comorbidities (cancer, stroke), the questions whether the deactivation of defibrillators is appropriate or must be regarded as active euthanasia may arise. Notable cases from the author's hospital are analyzed. The literature on the topic euthanasia and basic literature regarding defibrillator therapy are discussed. It is undisputed that patients as part of their self-determination have the right to renounce treatment. Active euthanasia and the thereby deliberate induction of death is prohibited by law in Germany and will be prosecuted. Passive euthanasia is the omission or reduction of possibly life-prolonging treatment measures. Passive euthanasia requires the patient's consent and is legally and ethically permissible. Indirect euthanasia takes into account acceleration of death as a side effect of a medication. Unpunishable assisted suicide ("assisted suicide") is the mere assistance of self-controlled and self-determined death. Assisted suicide is fundamentally not a criminal offense in Germany. Deactivation of a defibrillator is a treatment discontinuation, which is only permitted in accordance with the wishes of the patient. It is not a question of passive or active euthanasia. Involvement of a local ethics committee and/or legal consultation is certainly useful and sometimes also allows previously unrecognized questions to be answered.

  16. Using a Combined Platform of Swarm Intelligence Algorithms and GIS to Provide Land Suitability Maps for Locating Cardiac Rehabilitation Defibrillators

    Science.gov (United States)

    KAFFASH-CHARANDABI, Neda; SADEGHI-NIARAKI, Abolghasem; PARK, Dong-Kyun

    2015-01-01

    Background: Cardiac arrest is a condition in which the heart is completely stopped and is not pumping any blood. Although most cardiac arrest cases are reported from homes or hospitals, about 20% occur in public areas. Therefore, these areas need to be investigated in terms of cardiac arrest incidence so that places of high incidence can be identified and cardiac rehabilitation defibrillators installed there. Methods: In order to investigate a study area in Petersburg, Pennsylvania State, and to determine appropriate places for installing defibrillators with 5-year period data, swarm intelligence algorithms were used. Moreover, the location of the defibrillators was determined based on the following five evaluation criteria: land use, altitude of the area, economic conditions, distance from hospitals and approximate areas of reported cases of cardiac arrest for public places that were created in geospatial information system (GIS). Results: The A-P HADEL algorithm results were more precise about 27.36%. The validation results indicated a wider coverage of real values and the verification results confirmed the faster and more exact optimization of the cost function in the PSO method. Conclusion: The study findings emphasize the necessity of applying optimal optimization methods along with GIS and precise selection of criteria in the selection of optimal locations for installing medical facilities because the selected algorithm and criteria dramatically affect the final responses. Meanwhile, providing land suitability maps for installing facilities across hot and risky spots has the potential to save many lives. PMID:26587471

  17. Decalogue of electric defibrillation Decálogo de la desfibrilación eléctrica

    Directory of Open Access Journals (Sweden)

    Elkín Ferdinand Cardona Duque

    2001-03-01

    Full Text Available Defibrillation is an emergency procedure and the only effective therapy for ventricular fibrillation. Electrical defibrillation delivers large amounts of current to the myocardium and thus depolarizes it, terminating ventricular fibrillation and other arrhythmias. A defibrillator is a device that administers a controlled electrical shock, allowing the operator to select a variable current at the precise moment, according to patient‘s condition. Understanding defibrillator‘s operation leads to more effective resuscitation rates and more therapeutic alternatives in patients with any cardiac electric disturbance. La desfibrilación es un procedimiento de emergencia y es la única terapia efectiva para el manejo de la fibrilación ventricular. La desfibrilación eléctrica libera corriente en gran cantidad al miocardio, despolarizándolo y terminando la fibrilación ventricular y otras arritmias. Un desfibrilador es un aparato que suministra un choque eléctrico en forma controlada, permitiendo al operador seleccionar una corriente variable en el momento oportuno, de acuerdo con la condición del paciente. El entendimiento del manejo del desfibrilador permite tasas de resucitación más efectivas y más alternativas terapéuticas en pacientes con trastornos del ritmo cardíaco.

  18. A first city-wide early defibrillation project in a German city: 5-year results of the Bochum against sudden cardiac arrest study

    Directory of Open Access Journals (Sweden)

    Hanefeld Christoph

    2010-06-01

    Full Text Available Abstract Background Immediate defibrillation is the decisive determinant of prognosis in patients suffering from cardiac/circulatory arrest caused by ventricular fibrillation (VF. Therefore, various national and international associations recommend that first responders use defibrillators as soon as possible and also recommend public access to early defibrillation programmes. Here we report the results of the first city-wide early defibrillation project in a large German urban area. Methods There were 155 automated external defibrillators (AEDs put into operation in the Bochum municipal area, and 6,294 people took part in cardiopulmonary resuscitation (CPR and AED training. Free, accessible AEDs were installed in places with large volumes of people. Additionally, emergency forces were progressively equipped with AEDs. Results Twelve AED administrations prior to the arrival of an emergency physician were recorded and analysed over a period of 5 years (08/2004-08/2009. Rhythm analysis via AED demonstrated VF in seven cases, non-malignant dysrhythmias in four cases and asystole in one case. Two of the seven patients with VF were successfully defibrillated and survived cardiac/circulatory arrest without any neurological sequelae. Eight of the 12 AED applications were performed by laymen. The mean time between switching the unit on and applying the electrodes to the patient was 39 seconds (SD +/-20 sec. On average, another 20 seconds elapsed before the AED recommendation of "shock delivery" was displayed, and a total of 96 seconds elapsed before shock administration (± 56 sec. Conclusion Consistent with other reports, our findings show that the organisation of a city-wide initiative by a project office combining public access and first-responder defibrillation programmes can be safe, feasible and successful. Our experiences confirm that strategic planning of AED placement is a prerequisite for successful, cost-effective resuscitation.

  19. Ascending-ramp biphasic waveform has a lower defibrillation threshold and releases less troponin I than a truncated exponential biphasic waveform.

    Science.gov (United States)

    Huang, Jian; Walcott, Gregory P; Ruse, Richard B; Bohanan, Scott J; Killingsworth, Cheryl R; Ideker, Raymond E

    2012-09-11

    We tested the hypothesis that the shape of the shock waveform affects not only the defibrillation threshold but also the amount of cardiac damage. Defibrillation thresholds were determined for 11 waveforms-3 ascending-ramp waveforms, 3 descending-ramp waveforms, 3 rectilinear first-phase biphasic waveforms, a Gurvich waveform, and a truncated exponential biphasic waveform-in 6 pigs with electrodes in the right ventricular apex and superior vena cava. The ascending, descending, and rectilinear waveforms had 4-, 8-, and 16-millisecond first phases and a 3.5-millisecond rectilinear second phase that was half the voltage of the first phase. The exponential biphasic waveform had a 60% first-phase and a 50% second-phase tilt. In a second study, we attempted to defibrillate after 10 seconds of ventricular fibrillation with a single ≈30-J shock (6 pigs successfully defibrillated with 8-millisecond ascending, 8-millisecond rectilinear, and truncated exponential biphasic waveforms). Troponin I blood levels were determined before and 2 to 10 hours after the shock. The lowest-energy defibrillation threshold was for the 8-milliseconds ascending ramp (14.6±7.3 J [mean±SD]), which was significantly less than for the truncated exponential (19.6±6.3 J). Six hours after shock, troponin I was significantly less for the ascending-ramp waveform (0.80±0.54 ng/mL) than for the truncated exponential (1.92±0.47 ng/mL) or the rectilinear waveform (1.17±0.45 ng/mL). The ascending ramp has a significantly lower defibrillation threshold and at ≈30 J causes 58% less troponin I release than the truncated exponential biphasic shock. Therefore, the shock waveform affects both the defibrillation threshold and the amount of cardiac damage.

  20. Slowing of electrical activity in ventricular fibrillation is not associated with increased defibrillation energies in the isolated rabbit heart

    Directory of Open Access Journals (Sweden)

    Jane eCaldwell

    2011-04-01

    Full Text Available Prolonged out-of-hospital ventricular fibrillation (VF arrests are associated with reduced ECG dominant frequency (DF and diminished defibrillation success. Partial reversal of ischaemia increases ECG DF and improves defibrillation outcome. We have investigated the metabolic components of ischaemia responsible for the decline in ECG DF and defibrillation success.Isolated Langendorff-perfused rabbit hearts were loaded with the voltage-sensitive dye RH237. Using a photodiode array, epicardial membrane potentials were recorded at 252 sites (15x15mm on the anterior surface of the left & right ventricles. Simultaneously, a global ECG was recorded. VF was induced by burst pacing, and after 60s, perfusion was either reduced to 6ml/min or the perfusate composition changed to impose hypoxia (95%N2/5%CO2, pH 6.7 (80%O2/20%CO2, or hyperkalaemia (8mM. Using Fast Fourier Transform, power spectra were created from the optical signals and the global ECG. The optical power spectra were summated to give a global power spectrum (pseudoECG. At 600s the minimum defibrillation voltage (MDV was determined by step-up protocol.During VF, the ECG and pseudoECG DF were reduced by low-flow ischaemia (9.0±1.0Hz, p<0.01, n=5 and raised [K+]o (12.2±1.3 Hz, p<0.05, n=7 compared to control (19.2±1.5 Hz, n=20, but were unaffected by acidic pHo (16.7±1.1 Hz, n=11 and hypoxia (14.0±1.2 Hz, n=10. In contrast, the MDV was raised by acidic pH (156.1±26.4V, p<0.001 and hypoxia (154.1±22.1V, p<0.01 compared to control (65.6±2.3V, but comparable changes were not observed in low-flow ischaemia (61.0±0.5V or raised [K+]o (56±3V. In summary, different metabolites are responsible for the reduction in DF and the increase in defibrillation energy during ischaemic VF.