Atrial electrogram quality in single-pass defibrillator leads with floating atrial bipole in patients with permanent atrial fibrillation and cardiac resynchronization therapy.

Science.gov (United States)

Sticherling, Christian; Müller, Dirk; Schaer, Beat A; Krüger, Silke; Kolb, Christof

2018-03-27

Many patients receiving cardiac resynchronization therapy (CRT) suffer from permanent atrial fibrillation (AF). Knowledge of the atrial rhythm is important to direct pharmacological or interventional treatment as well as maintaining AV-synchronous biventricular pacing if sinus rhythm can be restored. A single pass single-coil defibrillator lead with a floating atrial bipole has been shown to obtain reliable information about the atrial rhythm but has never been employed in a CRT-system. The purpose of this study was to assess the feasibility of implanting a single coil right ventricular ICD lead with a floating atrial bipole and the signal quality of atrial electrograms (AEGM) in CRT-defibrillator recipients with permanent AF. Seventeen patients (16 males, mean age 73 ± 6 years, mean EF 25 ± 5%) with permanent AF and an indication for CRT-defibrillator placement were implanted with a designated CRT-D system comprising a single pass defibrillator lead with a atrial floating bipole. They were followed-up for 103 ± 22 days using remote monitoring for AEGM transmission. All patients had at last one AEGM suitable for atrial rhythm diagnosis and of 100 AEGM 99% were suitable for visual atrial rhythm assessment. Four patients were discharged in sinus rhythm and one reverted to AF during follow-up. Atrial electrograms retrieved from a single-pass defibrillator lead with a floating atrial bipole can be reliably used for atrial rhythm diagnosis in CRT recipients with permanent AF. Hence, a single pass ventricular defibrillator lead with a floating bipole can be considered in this population. Copyright © 2018 Indian Heart Rhythm Society. Production and hosting by Elsevier B.V. All rights reserved.

Does the atrioventricular node conduct?

NARCIS (Netherlands)

Meijler, F.L.; Fisch, C.

1989-01-01

It is difficult to be certain wh en the term "conduction" was first applied to the transfer of atrial activation to the ventricles .' In 1894, Engelmann used the word "Leitung", which can be translated as "connection" or as "conduction" .2 In 1906, Tawara described the atrioventricular node,

Cardiorespiratory interactions in patients with atrial flutter.

Science.gov (United States)

Masè, Michela; Disertori, Marcello; Ravelli, Flavia

2009-01-01

Respiratory sinus arrhythmia (RSA) is generally known as the autonomically mediated modulation of the sinus node pacemaker frequency in synchrony with respiration. Cardiorespiratory interactions have been largely investigated during sinus rhythm, whereas little is known about interactions during reentrant arrhythmias. In this study, cardiorespiratory interactions at the atrial and ventricular level were investigated during atrial flutter (AFL), a supraventricular arrhythmia based on a reentry, by using cross-spectral analysis and computer modeling. The coherence and phase between respiration and atrial (gamma(AA)(2), phi(AA)) and ventricular (gamma(RR)(2), phi(RR)) interval series were estimated in 20 patients with typical AFL (68.0 +/- 8.8 yr) and some degree of atrioventricular (AV) conduction block. In all patients, atrial intervals displayed oscillations strongly coupled and in phase with respiration (gamma(AA)(2)= 0.97 +/- 0.05, phi(AA) = 0.71 +/- 0.31 rad), corresponding to a paradoxical lengthening of intervals during inspiration. The modulation pattern was frequency independent, with in-phase oscillations and short time delays (0.40 +/- 0.15 s) for respiratory frequencies in the range 0.1-0.4 Hz. Ventricular patterns were affected by AV conduction type. In patients with fixed AV conduction, ventricular intervals displayed oscillations strongly coupled (gamma(RR)(2)= 0.97 +/- 0.03) and in phase with respiration (phi(RR) = 1.08 +/- 0.80 rad). Differently, in patients with variable AV conduction, respiratory oscillations were secondary to Wencheback rhythmicity, resulting in a decreased level of coupling (gamma(RR)(2)= 0.50 +/- 0.21). Simulations with a simplified model of AV conduction showed ventricular patterns to originate from the combination of a respiratory modulated atrial input with the functional properties of the AV node. The paradoxical frequency-independent modulation pattern of atrial interval, the short time delays, and the complexity of

Importance of gradients in membrane properties and electrical coupling in sinoatrial node pacing.

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Shin Inada

Full Text Available The sinoatrial node (SAN is heterogeneous in terms of cell size, ion channels, current densities, connexins and electrical coupling. For example, Nav1.5 (responsible for INa and Cx43 (responsible for electrical coupling are absent from the centre of the SAN (normally the leading pacemaker site, but present in the periphery (at SAN-atrial muscle junction. To test whether the heterogeneity is important for the functioning of the SAN, one- and two-dimensional models of the SAN and surrounding atrial muscle were created. Normal functioning of the SAN (in terms of cycle length, position of leading pacemaker site, conduction times, activation and repolarization sequences and space constants was observed when, from the centre to the periphery, (i cell characteristics (cell size and ionic current densities were changed in a gradient fashion from a central-type (lacking INa to a peripheral-type (possessing INa and (ii coupling conductance was increased in a gradient fashion. We conclude that the heterogeneous nature of the node is important for its normal functioning. The presence of Nav1.5 and Cx43 in the periphery may be essential for the node to be able to drive the atrial muscle: Nav1.5 provides the necessary depolarizing current and Cx43 delivers it to the atrial muscle.

Long-term benefits of education by emergency care nurses at discharge of patients with atrial fibrillation.

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Fuenzalida, Carolina; Hernández, Gritzel; Ferro, Inés; Siches, Carme; Ambrós, Àngels; Coll-Vinent, Blanca

2017-11-01

Health education improves the prognosis of many diseases. A previous study in patients with atrial fibrillation (AF) showed that an educational intervention by nurses at discharge from the emergency room (ER) decreased AF-related complications at 3-month follow-up. Our objective was to determine whether this intervention had a long-term effect. A prospective study assessed the outcomes of an intervention carried out upon discharge from the ER. Patients with a diagnosis of AF were randomized into two groups: the intervention group and the control group. The intervention consisted of a basic explanation about the arrhythmia and its treatment, precautions and warning signs, a training to take their pulse, and an individualized informational leaflet. At one year of follow-up, the clinical records for all participants were reviewed. The primary variable was the combined endpoint of AF-related or treatment-related complications and death. The study included 240 patients (116 intervention and 124 control), mean age 76.1±10.9years. The primary variable was significantly lower in the intervention group (31.9% vs 48.4%; p=0.005). Education by ER nurses at patient discharge helped to decrease AF-related complications at one year of follow-up. Copyright © 2017. Published by Elsevier Ltd.

Atrial septal defect in a Korean wild raccoon dog.

Science.gov (United States)

Yim, Soomi; Choi, Sooyoung; Kim, Jongtaek; Chung, Jin-Young; Park, Inchul

2017-10-07

An approximately two-year-old, male 6.1 kg body weight, Korean wild raccoon dog (Nyctereutes procyonoides koreensis) was captured by the wildlife medical rescue center of Kangwon National University. Upon physical examination, the heart rate was 87 beats per min and there were no clinical signs. The hematological, and blood biochemical profiles revealed no remarkable findings; however, thoracic radiographs showed cardiac enlargement, especially in the right atrium. On electrocardiogram, sinus node dysfunction and bradyarrhythmia were revealed. Echocardiography showed a left-to-right shunting atrial septal defect. Based on these findings, this Korean wild raccoon dog was diagnosed with atrial septal defect. This is the rare case report of atrial septal defect in wildlife.

Surgical Treatment of Atrial Fibrillation in Patients with Rheumatic Valve Disease

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Ernesto Koehler Chavez

Full Text Available Abstract Objective: To assess heart rhythm and predictive factors associated with sinus rhythm after one year in patients with rheumatic valve disease undergoing concomitant surgical treatment of atrial fibrillation. Operative mortality, survival and occurrence of stroke after one year were also evaluated. Methods: Retrospective longitudinal observational study of 103 patients undergoing rheumatic mitral valve surgery and ablation of atrial fibrillation using uni- or bipolar radiofrequency between January 2013 and December 2014. Age, gender, functional class (NYHA, type of atrial fibrillation, EuroSCORE, duration of atrial fibrillation, stroke, left atrial size, left ventricular ejection fraction, cardiopulmonary bypass time, myocardial ischemia time and type of radiofrequency were investigated. Results: After one year, 66.3% of patients were in sinus rhythm. Sinus rhythm at hospital discharge, lower left atrial size in the preoperative period and bipolar radiofrequency were associated with a greater chance of sinus rhythm after one year. Operative mortality was 7.7%. Survival rate after one year was 92.3% and occurrence of stroke was 1%. Conclusion: Atrial fibrillation ablation surgery with surgical approach of rheumatic mitral valve resulted in 63.1% patients in sinus rhythm after one year. Discharge from hospital in sinus rhythm was a predictor of maintenance of this rhythm. Increased left atrium and use of unipolar radiofrequency were associated with lower chance of sinus rhythm. Operative mortality rate of 7.7% and survival and stroke-free survival contribute to excellent care results for this approach.

Health status, geriatric syndromes and prescription of oral anticoagulant therapy in elderly medical inpatients with atrial fibrillation.

Science.gov (United States)

Bo, Mario; Sciarrillo, Irene; Maggiani, Guido; Falcone, Yolanda; Iacovino, Marina; Grisoglio, Enrica; Fonte, Gianfranco; Grosjean, Simon; Gaita, Fiorenzo

2017-03-01

The aim of the present study was to investigate the prevalence of geriatric syndromes among older medical inpatients with atrial fibrillation, and their association with use of vitamin K antagonists. A retrospective study of patients aged ≥65 years discharged with a diagnosis of atrial fibrillation from the Acute Geriatric Ward was carried out. Stroke and bleeding risk were evaluated according to the CHA 2 DS 2 -VASC and HAS-BLED scores. Comorbidity, cognitive status, functional autonomy and contraindications to vitamin K antagonists were also considered. Atrial fibrillation was documented in 1078 of 3650 patients (29.5%, mean age 83.4 ± 6.6 years, 60.3% women). Contraindications to vitamin K antagonists were documented in 24.9% of patients. Prescription of vitamin K antagonists at discharge was 37.8% and 47.9%, in the overall sample and in those without contraindications, respectively. In the overall sample, prescription of vitamin K antagonists was associated with younger age, permanent/persistent atrial fibrillation, home discharge, less comorbidity, higher hemoglobin levels, better functional independence, known atrial fibrillation at admission and lower HAS-BLED score. Among patients without contraindications to vitamin K antagonists, their use at discharge was independently associated with younger age, permanent/persistent atrial fibrillation, home discharge, higher hemoglobin levels and CHA2DS2-VASC score, better functional autonomy, and greater number of drugs. We showed a high prevalence of atrial fibrillation among older medical inpatients, who have a poor health status and a high prevalence of geriatric syndromes. Vitamin K antagonists were prescribed in less than half of the patients; underuse was mainly accounted for by a high prevalence of comorbidities/contraindications, poor health status and limited functional autonomy. Geriatr Gerontol Int 2017; 17: 416-423. © 2016 Japan Geriatrics Society.

Atrial fibrillation in fracture patients treated with oral bisphosphonates

DEFF Research Database (Denmark)

Abrahamsen, B; Eiken, P; Brixen, K

2009-01-01

OBJECTIVES: To determine if patients receiving oral bisphosphonates are at excess risk of atrial fibrillation (AF), stroke and myocardial infarction. DESIGN: Register-based restricted cohort study. SETTING: National Hospital Discharge Register and National Prescriptions Database (1995-2005). SUBJ......OBJECTIVES: To determine if patients receiving oral bisphosphonates are at excess risk of atrial fibrillation (AF), stroke and myocardial infarction. DESIGN: Register-based restricted cohort study. SETTING: National Hospital Discharge Register and National Prescriptions Database (1995...... to adherence. There was no increased risk of ischaemic stroke and an increased risk of myocardial infarction was not significant after adjustment for comorbidity. CONCLUSIONS: The increased occurrence of AF in fracture patients who are users of oral bisphosphonates should be attributed to targeting...

The Impact of Age on the Epidemiology of Atrial Fibrillation Hospitalizations

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Naderi, Sahar; Wang, Yun; Miller, Amy L.; Rodriguez, Fátima; Chung, Mina K.; Radford, Martha J.; Foody, JoAnne M.

2015-01-01

Background Given 4 million individuals in the United States suffer from atrial fibrillation, understanding the epidemiology of this disease is crucial. We sought to identify and characterize the impact of age on national atrial fibrillation hospitalization patterns. Methods The study sample was drawn from the 2009–2010 Nationwide Inpatient Sample (NIS). Patients hospitalized with a principal ICD9 discharge diagnosis of atrial fibrillation were included. Patients were categorized as “older” (65 and older) or “younger” (under 65 years) for the purposes of analysis. The outcomes measured included hospitalization rate, length of stay, in-hospital mortality, and discharge status. Results We identified 192,846 atrial fibrillation hospitalizations. There was significant geographic variation in hospitalizations for both younger and older age groups. States with high hospitalizations differed from those states known to have high stroke mortality. Younger patients (33% of the sample) were more likely to be obese (21% versus 8%, patrial fibrillation hospitalizations in contemporary practice. Younger patients are healthier, with a different distribution of risk factors, than older patients who have higher associated morbidity and mortality. PMID:24332722

Long-Term Effects of Atrial Ganglionated Plexi Ablation on Function and Structure of Sinoatrial and Atrioventricular Node in Canine.

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Zhang, Ming; Wang, Ximin; Xie, Xinxing; Wang, Zhongsu; Liu, Xiaoyan; Guan, Juan; Wang, Weizong; Li, Zhan; Wang, Jiangrong; Gao, Mei; Hou, Yinglong

2015-10-01

Long-term effects of ganglionated plexi (GP) ablation on sinoatrial node (SAN) and atrioventricular node (AVN) remain unclear. This study is to investigate the long-term effects of ablation of cardiac anterior right GP (ARGP) and inferior right GP (IRGP) on function and structure of SAN and AVN in canine. Thirty-two dogs were randomly divided into an operated group (n = 24) and sham-operated group (n = 8). ARGP and IRGP were ablated in operated group which was randomly divided into three subgroups according to the period of evaluation after operation (1 month, 6 months, 12 months). The functional and histological characteristics of SAN and AVN, as well as the expression of connexin (Cx) 43 and Cx 45 in SAN and AVN, were evaluated before and after ablation. Resting heart rate was increased and AVN effective refractory period was prolonged and sinus node recovery time (SNRT) and corrected SNRT were shortened immediately after ablation. These changes were reverted to preablation level after 1 month. At 1 month, ventricular rate during atrial fibrillation was slowed, atria-His intervals were prolonged, and Cx43 and Cx45 expression in SAN and AVN were downregulated. At 6 months, all changes were reverted to preablation level. The histological characteristics of SAN and AVN did not change. Ablation of ARGP and IRGP has short-term effects on function and structure of SAN and AVN rather than long-term effects, which suggests that ablation of ARGP and IRGP is safe. Atrioventricular conduction dysfunction after ablation may be related to downregulated Cx43 and Cx45 expression in AVN. © 2015 Wiley Periodicals, Inc.

Stroke prevention in hospitalized patients with atrial fibrillation: a population-based study.

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Nagpal, Seema; Anderson, David; Putnam, Wayne; Flowerdew, Gordon; Gardner, Martin; Cox, Jafna

2003-01-01

Oral anticoagulants reduce the incidence of stroke by 68%, yet suboptimal use has been documented in surveys of patients with atrial fibrillation. The present study examined current patterns of anticoagulant use for patients hospitalized with atrial fibrillation across an entire health care system. Improving Cardiovascular Outcomes in Nova Scotia (ICONS) is a prospective cohort study involving all patients hospitalized in Nova Scotia with atrial fibrillation, among other conditions. Consecutive inpatients with atrial fibrillation from October 15, 1997 to October 14, 1998 were studied. Detailed demographic and clinical data were collected and the proportion of patients using antithrombotic therapy was tabulated by risk category. Multivariate logistic regression was used to assess the relationship of various demographic and clinical factors with the use of antithrombotic agents. There were 2202 patients hospitalized with atrial fibrillation; 644 admitted specifically for this condition. Only 21% of patients admitted with atrial fibrillation were on warfarin sodium at admission and this increased by time of discharge. Diabetes was negatively correlated with warfarin sodium use. Histories of prosthetic valve replacement, stroke/transient ischemic attack, and heart failure were positively associated with anticoagulant use on admission. Patients with prosthetic valve replacement, heart failure, or hyperlipidemia were most likely to receive anticoagulants at discharge. Antithrombotic agents remain underused by patients with atrial fibrillation. While higher risk patients are generally targeted, this is not invariably the case; thus, diabetics remain under treated. Further work is needed to explain such anomalous practice and promote optimal antithrombotic therapy use.

Cerebral sino-venous thrombosis

International Nuclear Information System (INIS)

Sayama, Ichiro; Kobayashi, Tsunesaburo; Nakajima, Kenji

1982-01-01

Three cases of cerebral sino-venous thrombosis were reported. Repeated CT findings were studied and discussed on account of the treatments for those pathologic conditions. Those of studied cases are; a 22-year-old postpartum woman, a 42-year-old woman with irregular vaginal bleeding, and a 26-year-old man with severe reactive emesis after drinking alcohol. They were treated conservatively. Case 1 died in its acute stage. In the remaining ones, each had an uneventful recovery. CT scan findings of them manifested their exact clinical conditions. These findings were devided into two categories, one was direct signs expressed sino-venous occlusion, the other was indirect signs which appeared as a result of these occlusion. Direct signs cannot always get in every cases with sino-venous occlusion, but as for indirect signs, we can get various changes corresponding to the time taken CT photoes, and they are useful to decide appropriate treatments at that time. Considering suitable treatments for this disease, it is necessary to select most suitable ones according to their pathologic conditions, which may be precisely drawn with CT scans. (J.P.N.)

Pacing for the Suppression of Paroxysmal Atrial Fibrillation in an 87-year-old Patient

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Adel El-Bialy

2003-04-01

Full Text Available Background: Sinus node dysfunction, atrioventricular (AV block and atrial fibrillation (AF are associated with advanced age. Required therapy commonly includes pacemaker implantation. Methods: We report the course of therapy for an 87-year-old with symptomatic sinus node dysfunction and paroxysmal atrial fibrillation who was intolerant of drug therapy. Results: The patient received a pacemaker for treatment of sick sinus syndrome. She continued to have symptomatic episodes of AF and was intolerant of pharmacologic therapy despite adequate rate support provided by the pacemaker. The AF suppression algorithm in the pacemaker was enabled, resulting in the elimination all AF episodes effectively eliminating the need for antiarrhythmic medication. If this continues to stabilize her atrium, withdrawal of anticoagulation therapy is anticipated. Conclusions: The clinical presentation of sinus node dysfunction and related conduction abnormalities is common in the elderly. Pharmacologic management is often a challenge in the presence of the advanced age and concomitant disease processes. In individuals who have paroxysmal atrial fibrillation or are likely to develop this and who need a pacemaker for standard indications, the availability of an AF Suppression™ algorithm may facilitate their management without needed to use medications or being able to utilize lower doses of those medications.

β-Blockers on Discharge From Acute Atrial Fibrillation Are Associated With Decreased Mortality and Lower Cerebrovascular Accidents in Patients With Heart Failure and Reduced Ejection Fraction.

Science.gov (United States)

Abi Khalil, Charbel; Zubaid, Mohammad; Asaad, Nidal; Rashed, Wafa A; Hamad, Adel Khalifa; Singh, Rajvir; Al Suwaidi, Jassim

2018-04-01

The benefits of β-blockers in patients with heart failure (HF) with reduced ejection fraction (HFrEF) and atrial fibrillation (AF) are controversial. The Gulf Survey of Atrial Fibrillation Events was a prospective, multinational, observational registry of consecutive patients with AF recruited from the emergency department (ED). We studied the incidence of 6- and 12-month mortality, hospitalization for HF or AF, and stroke/transient ischemic attacks (TIAs) in patients with HFrEF, in relation to β-blockers on discharge from the ED or the subsequent hospital stay. Of the 344 patients with HFrEF and AF in the GULF-SAFE, 177 patients (53%) were discharged on β-blockers. Mortality was lower in those patients compared with the non-β-blockers group at 6 and 12 months (odds ratios [ORs] 0.31, 95% CI [0.16-0.61]; OR 0.30, 95% CI [0.16-0.55]; P = .001 for both, respectively), so was the risk of stroke/TIAs. However, hospitalizations for AF increased in the β-blockers group. Even after adjustment for several risk variables in 2 different models, the beneficial effect of β-blockers on mortality persisted, at the cost of more hospitalization for AF.

Right atrial isolation associated with atrial septal closure in patients with atrial septal defect and chronic atrial fibrillation.

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Minzioni, G; Graffigna, A; Pagani, F; Vigano, M

1993-12-01

To restore sinus rhythm in the remaining heart chambers of six adult patients with atrial septal defect and chronic or paroxysmal atrial fibrillation, electrical, right atrial isolation associated with surgical correction of the defect was performed. All but one patient was free from atrial fibrillation without medication 2-25 months after operation. The isolated right atrial appendages showed intrinsic rhythmical activity in five patients and no electrical activity in one. Right atrial isolation is a safe and effective procedure that abolishes atrial fibrillation in patients with arrhythmia after surgical correction of atrial septal defect.

Left atrial thrombus following bilobectomy: a case report

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Kaya Ugur

2010-02-01

Full Text Available Abstract Introduction Left atrial free floating ball thrombus is a relatively rare event, especially without mitral valve disease. Case presentation A 61-year-old Turkish man was admitted to our hospital with a thrombus mass in his left atrium. Five months earlier, he had undergone right bilobectomy and superior bronchoplasty due to squamous cell carcinoma in the lung. The patient had no evidence of cardiac disease except atrial fibrillation and there were no defined embolizations. The thrombus mass was surgically removed. The patient was discharged from hospital on the sixth postoperative day. Conclusion Surgery with cardiopulmonary bypass is a safe method for treatment. The patient should be medicated with warfarin, especially in the presence of atrial fibrillation.

[Catheter ablation of ectopic incessant atrial tachycardia using radiofrequency. Reversion of tachycardiomyopathy].

Science.gov (United States)

de Paola, A A; Mendonça, A; Balbão, C E; Tavora, M Z; da Silva, R M; Hara, V M; Guiguer Júnior, N; Vattimo, A C; Souza, I A; Portugal, O P

1993-10-01

A 8-year-old female patient with refractory incessant atrial tachycardia, very symptomatic and with left ventricular ejection fraction of 0.25. Electrophysiological study and endocardial mapping localized the site of the origin of atrial tachycardia in the superior right atrium. In this site 2 applications of radiofrequency current (25V, 20 and 50 seconds) resulted in termination of the atrial tachycardia. She was discharged off antiarrhythmic drugs and after 2 months ejection fraction was 0.52. She was completely asymptomatic 6 months after ablation procedure.

Spontaneous Transition of Double Tachycardias with Atrial Fusion in a Patient with Wolff-Parkinson-White Syndrome.

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Kim, Dongmin; Lee, Myung-Yong

2016-07-01

Among patients with Wolff-Parkinson-White syndrome, atrioventricular reciprocating tachycardia (AVRT) and atrioventricular nodal reentrant tachycardia (AVNRT) can coexist in a single patient. Direct transition of both tachycardias is rare; however, it can occur after premature atrial or ventricular activity if the cycle lengths of the two tachycardias are similar. Furthermore, persistent atrial activation by an accessory pathway (AP) located outside of the AV node during ongoing AVNRT is also rare. This article describes a case of uncommon atrial activation by an AP during AVNRT and gradual transition of the two supraventricular tachycardias without any preceding atrial or ventricular activity in a patient with preexcitation syndrome.

The functions of atrial strands interdigitating with and penetrating into sinoatrial node: a theoretical study of the problem.

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Xiaodong Huang

Full Text Available The sinoatrial node (SAN-atrium system is closely involved with the activity of heart beating. The impulse propagation and phase-locking behaviors of this system are of theoretical interest. Some experiments have revealed that atrial strands (ASs interdigitate with and penetrate into the SAN, whereby the SAN-atrium system works as a complex network. In this study, the functions of ASs are numerically investigated using realistic cardiac models. The results indicate that the ASs penetrating into the central region of the SAN play a major role in propagating excitation into the atrium. This is because the threshold SAN-AS coupling for an AS to function as an alternative path for propagation is lower at the center than at the periphery. However, ASs penetrating into the peripheral region have a great effect in terms of enlarging the 1:1 entrainment range of the SAN because the automaticity of the SAN is evidently reduced by ASs. Moreover, an analytical formula for approximating the enlargement of the 1:1 range is derived.

Importance of Close Follow-Up in the Fetus with Premature Atrial Contractions Accompanied by Atrial Septal Aneurysm: A Case Report

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Yilmaz Yozgat

2013-01-01

Full Text Available Rhythms that derive from parts of atria other than the sinus node are called premature atrial contractions (PACs. Vast majority of fetal PACs are idiopathic. Fetal PACs usually have a good prognosis and disappear spontaneously during pregnancy or after delivery. Development of fetal tachycardia or fetal bradycardia is rarely reported during follow-up of fetuses diagnosed with PACs. To the best of our knowledge, coexistence of tachycardia and bradycardia leading to hemodynamic impairment has not yet been reported. We present a fetus diagnosed with PACs and atrial septal aneurysm (ASA on the 23rd week of gestation proceeding to fetal bradycardia and fetal tachycardia and consequently hemodynamic impairment. We suggest closer follow-up of fetuses with PACs accompanied by ASA.

The incidence and prognostic significance of new-onset atrial fibrillation in patients with acute myocardial infarction and left ventricular systolic dysfunction: a CARISMA substudy

DEFF Research Database (Denmark)

Jons, Christian; Jacobsen, Uffe G; Joergensen, Rikke Moerch

2011-01-01

The incidence and risk associated with new-onset atrial fibrillation (AF) occurring after discharge in patients with acute myocardial infarction (MI) remains unknown.......The incidence and risk associated with new-onset atrial fibrillation (AF) occurring after discharge in patients with acute myocardial infarction (MI) remains unknown....

[Atypical sinus node dysfunction. Usefulness of implantable Holter. A case report].

Science.gov (United States)

Martí Almor, J; Delclòs Urgell, J; Bruguera Cortada, J

2001-12-01

We present an 84 year-old female patient with repeated syncopes/presyncopes in the last nine years. All diagnosis tests were negative, including ECG, 24-hour Holter, tilt table test and EP study. Therefore, a subcutaneous insertable loop recorder was implanted (Reveal). The recording of three episodes showed the association of presyncope with the onset of atrial fibrilation and, in two syncopes, with an atrial pause between AF episodes. Probably an abnormal prolonged sinus node recovery time (more than 6 s) allowed AF to restart before the sinus rhythm.

[Left atrial electric isolation in the treatment of atrial fibrillation secondary to rheumatic valvular disease].

Science.gov (United States)

Graffigna, A; Pagani, F; Minzioni, G; Salerno, J; Viganò, M

1992-08-01

Surgical isolation of the left atrium was performed for the treatment of chronic atrial fibrillation secondary to valvular disease in 100 patients who underwent valve surgery. From May 1989 to September 1991, 62 patients underwent mitral valve surgery (Group I), 19 underwent mitral valve surgery and DeVega tricuspid annuloplasty (Group II), 15 underwent mitral and aortic surgery (Group III), and 4 patients underwent mitral and aortic surgery and DeVega tricuspid annuloplasty (Group IV). Left atrial isolation was performed prolonging the usual left paraseptal atriotomy towards the left fibrous trigone anteriorly, and the postero-medial commissure posteriorly. The incision was conducted a few millimeters apart from the mitral valve annulus, and cryolesion were placed at the edges to ensure complete electrophysiological isolation of the left atrium. Operative mortality accounted for 3 cases (3%). In 79 patients (81.4%) sinus rhythm recovered and persisted until discharge from the hospital. No differences were found between the groups (Group I: 80.7%; Group II: 68.5%; Group III 86.7%, Group IV 75% - p = N.S.). Three cases of late mortality (3.1%) were registered. long-term results showed persistence of SR in 71% of Group I, 61.2% of Group II, 85.8% of Group III, and 100% of Group IV. The unique risk factor for late recurrency of atrial fibrillation was found to be a duration of preoperative AF longer than 6 months. Due to the high success rate in recovering the sinus rhythm, we suggest left atrial isolation in patients with chronic atrial fibrillation undergoing valvular surgery.

Interatrial septum pacing decreases atrial dyssynchrony on strain rate imaging compared with right atrial appendage pacing.

Science.gov (United States)

Yasuoka, Yoshinori; Abe, Haruhiko; Umekawa, Seiko; Katsuki, Keiko; Tanaka, Norio; Araki, Ryo; Imanaka, Takahiro; Matsutera, Ryo; Morisawa, Daisuke; Kitada, Hirokazu; Hattori, Susumu; Noda, Yoshiki; Adachi, Hidenori; Sasaki, Tatsuya; Miyatake, Kunio

2011-03-01

Interatrial septum pacing (IAS-P) decreases atrial conduction delay compared with right atrial appendage pacing (RAA-P). We evaluate the atrial contraction with strain rate of tissue Doppler imaging (TDI) during sinus activation or with IAS-P or RAA-P. Fifty-two patients with permanent pacemaker for sinus node disease were enrolled in the study. Twenty-three subjects were with IAS-P and 29 with RAA-P. The time from end-diastole to peak end-diastolic strain rate was measured and corrected with RR interval on electrocardiogram. It was defined as the time from end-diastole to peak end-diastolic strain rate (TSRc), and the balance between maximum and minimum TSRc at three sites (ΔTSRc) was compared during sinus activation and with pacing rhythm in each group. There were no significant differences observed in general characteristics and standard echocardiographic parameters except the duration of pacing P wave between the two groups. The duration was significantly shorter in the IAS-P group compared with the RAA-P group (95 ± 34 vs 138 ± 41; P = 0.001). TSRc was significantly different between sinus activation and pacing rhythm (36.3 ± 35.7 vs 61.6 ± 36.3; P = 0.003) in the RAA-P group, whereas no significant differences were observed in the IAS-P group (25.4 ± 12.1 vs 27.7 ± 14.7; NS). During the follow-up (mean 2.4 ± 0.7 years), the incidence of paroxysmal atrial fibrillation (AF) conversion to permanent AF was not significantly different between the two groups. IAS-P decreased the contraction delay on atrial TDI compared to RAA-P; however, it did not contribute to the reduction of AF incidence in the present study. ©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.

Comparison of costs and discharge outcomes for patients hospitalized for ischemic or hemorrhagic stroke with or without atrial fibrillation in the United States.

Science.gov (United States)

Pan, Xianying; Simon, Teresa A; Hamilton, Melissa; Kuznik, Andreas

2015-05-01

This retrospective analysis investigated the impact of baseline clinical characteristics, including atrial fibrillation (AF), on hospital discharge status (to home or continuing care), mortality, length of hospital stay, and treatment costs in patients hospitalized for stroke. The analysis included adult patients hospitalized with a primary diagnosis of ischemic or hemorrhagic stroke between January 2006 and June 2011 from the premier alliance database, a large nationally representative database of inpatient health records. Patients included in the analysis were categorized as with or without AF, based on the presence or absence of a secondary listed diagnosis of AF. Irrespective of stroke type (ischemic or hemorrhagic), AF was associated with an increased risk of mortality during the index hospitalization event, as well as a higher probability of discharge to a continuing care facility, longer duration of stay, and higher treatment costs. In patients hospitalized for a stroke event, AF appears to be an independent risk factor of in-hospital mortality, discharge to continuing care, length of hospital stay, and increased treatment costs.

AV nodal function during atrial fibrillation: the role of electrotonic modulation of propagation

NARCIS (Netherlands)

Meijler, F.L.; Jalife, J.; Beaumont, J.; Vaidya, D.

1996-01-01

The irregular ventricular rhythm that accompanies atrial fibrillation (AF) has been explained in terms of concealed conduction within the AV node (AVN). However, the cellular basis of concealed conduction in AF remains poorly understood. Our hypothesis is that electrotonic modulation of AVN

Do prehospital discharge pacemaker checks provide any additional clinical benefit?

Science.gov (United States)

Wheelan, Kevin R; Legge, Darlene M; Sakowski, Brent C; Bruce, Susan S; Roberts, David C; Johnston, L Murphy; Moore, B Jane; Beveridge, Thomas P; Wells, Peter J; Vallabahn, Ravi; Donsky, Michael S; Franklin, Jay O

2005-08-01

We performed a retrospective analysis of 250 records of consecutive, newly implanted, pacemaker patients from a single center to determine the rate of postimplant complications and observations discovered before and during the prehospital discharge evaluation. No observations occurred in 246 of 250 patients (98.4%) (1-sided 95% confidence interval 96.4%). Of the 250 patients, 4 had observations that were discovered at the prehospital discharge check and required reprogramming to increase the sensitivity safety margin (3 atrial and 1 ventricular). We documented only 1 complication that was discovered before the predischarge evaluation through telemetry and resulted in an atrial lead revision.

Water quality assessment of the Sinos River, Southern Brazil.

Science.gov (United States)

Blume, K K; Macedo, J C; Meneguzzi, A; Silva, L B; Quevedo, D M; Rodrigues, M A S

2010-12-01

The Sinos River basin is located Northeast of the state of Rio Grande do Sul (29º 20' to 30º 10' S and 50º 15' to 51º20'W), Southern Brazil, covering two geomorphologic provinces: the Southern plateau and central depression. It is part of the Guaíba basin and has an area of approximately 800 km², encompassing 32 municipalities. The objective of this study was to monitor water quality in the Sinos River, the largest river in this basin. Water samples were collected at four selected sites in the Sinos River, and the following parameters were analysed: pH, dissolved oxygen, biochemical oxygen demand (BOD₅), turbidity, fecal coliforms, total dissolved solids, temperature, nitrate, nitrite, phosphorous, chromium, lead, aluminum, zinc, iron, and copper. The results were analysed based on Resolution No. 357/2005 of the Brazilian National Environmental Council (CONAMA) regarding regulatory limits for residues in water. A second analysis was performed based on a water quality index (WQI) used by the Sinos River Basin Management Committee (COMITESINOS). Poor water quality in the Sinos River presents a worrying scenario for the region, since this river is the main source of water supply for the urban core. Health conditions found in the Sinos River, mainly in its lower reaches, are worrying and a strong indicator of human activities on the basin.

Water quality assessment of the Sinos River, Southern Brazil

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KK. Blume

Full Text Available The Sinos River basin is located Northeast of the state of Rio Grande do Sul (29º 20' to 30º 10' S and 50º 15' to 51º20'W, Southern Brazil, covering two geomorphologic provinces: the Southern plateau and central depression. It is part of the Guaíba basin and has an area of approximately 800 km², encompassing 32 municipalities. The objective of this study was to monitor water quality in the Sinos River, the largest river in this basin. Water samples were collected at four selected sites in the Sinos River, and the following parameters were analysed: pH, dissolved oxygen, biochemical oxygen demand (BOD5, turbidity, fecal coliforms, total dissolved solids, temperature, nitrate, nitrite, phosphorous, chromium, lead, aluminum, zinc, iron, and copper. The results were analysed based on Resolution No. 357/2005 of the Brazilian National Environmental Council (CONAMA regarding regulatory limits for residues in water. A second analysis was performed based on a water quality index (WQI used by the Sinos River Basin Management Committee (COMITESINOS. Poor water quality in the Sinos River presents a worrying scenario for the region, since this river is the main source of water supply for the urban core. Health conditions found in the Sinos River, mainly in its lower reaches, are worrying and a strong indicator of human activities on the basin.

Investigations on Rickettsia in Ticks at the Sino-Russian and Sino-Mongolian Borders, China.

Science.gov (United States)

Liu, Lijuan; Chen, Qian; Yang, Yu; Wang, Jiancheng; Cao, Xiaomei; Zhang, Sheng; Li, Hong; Hou, Yong; Wang, Fuxiang; Xu, Baoliang

2015-12-01

To describe the prevalence of Rickettsia in ticks at the Sino-Russian and Sino-Mongolian borders, a total of 292 ticks were collected and tested by conventional PCR assays. The prevalence of Rickettsia was 53.4%, and phylogenetic analysis showed that they belonged to R. raoultii species after alignment for the ompA, ompB, and gltA genes, respectively. Coxiella burnetii DNA was detected for 14%, and no Ehrlichia, Borrelia burgdorferi, and Babesia species were found. Co-infection of two pathogens was 9.9%, and no co-infection with three or more pathogens was found. This study suggested Rickettsia was the most common pathogen in the ticks and co-infection was found. The findings might be helpful to provide advice on the prevention and control of tick-borne disease potential for tourists and residents.

Cytosolic calcium ions exert a major influence on the firing rate and maintenance of pacemaker activity in guinea-pig sinus node.

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Rebecca Anne Capel

2015-02-01

Full Text Available The sino-atrial node (SAN provides the electrical stimulus to initiate every heart beat. Cellular processes underlying this activity have been debated extensively, especially with regards to the role of intracellular calcium. We have used whole-cell application of 1,2-bis(o-aminophenoxyethane-N,N,N',N'-tetraacetic acid (BAPTA, a rapid calcium chelator, to guinea pig isolated SAN myocytes to assess the effect of rapid reduction of intracellular calcium on SAN cell electrical activity. High-dose (10 mM BAPTA induced rapid and complete cessation of rhythmic action potential (AP firing (time to cessation 5.5±1.7 s. Over a range of concentrations, BAPTA induced slowing of action potential firing and disruption of rhythmic activity, which was dose-dependent in its time of onset. Exposure to BAPTA was associated with stereotyped action potential changes similar to those previously reported in the presence of ryanodine, namely depolarisation of the most negative diastolic potential, prolongation of action potentials and a reduction in action potential amplitude. These experiments are consistent with the view that cytosolic calcium is essential to the maintenance of rhythmic pacemaker activity.

Atrial therapies reduce atrial arrhythmia burden in defibrillator patients.

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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.

Contribution of small conductance K+ channels to sinoatrial node pacemaker activity: insights from atrial-specific Na+ /Ca2+ exchange knockout mice.

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Torrente, Angelo G; Zhang, Rui; Wang, Heidi; Zaini, Audrey; Kim, Brian; Yue, Xin; Philipson, Kenneth D; Goldhaber, Joshua I

2017-06-15

Repolarizing currents through K + channels are essential for proper sinoatrial node (SAN) pacemaking, but the influence of intracellular Ca 2+ on repolarization in the SAN is uncertain. We identified all three isoforms of Ca 2+ -activated small conductance K + (SK) channels in the murine SAN. SK channel blockade slows repolarization and subsequent depolarization of SAN cells. In the atrial-specific Na + /Ca 2+ exchanger (NCX) knockout mouse, cellular Ca 2+ accumulation during spontaneous SAN pacemaker activity produces intermittent hyperactivation of SK channels, leading to arrhythmic pauses alternating with bursts of pacing. These findings suggest that Ca 2+ -sensitive SK channels can translate changes in cellular Ca 2+ into a repolarizing current capable of modulating pacemaking. SK channels are a potential pharmacological target for modulating SAN rate or treating SAN dysfunction, particularly under conditions characterized by abnormal increases in diastolic Ca 2+ . Small conductance K + (SK) channels have been implicated as modulators of spontaneous depolarization and electrical conduction that may be involved in cardiac arrhythmia. However, neither their presence nor their contribution to sinoatrial node (SAN) pacemaker activity has been investigated. Using quantitative PCR (q-PCR), immunostaining and patch clamp recordings of membrane current and voltage, we identified all three SK isoforms (SK1, SK2 and SK3) in mouse SAN. Inhibition of SK channels with the specific blocker apamin prolonged action potentials (APs) in isolated SAN cells. Apamin also slowed diastolic depolarization and reduced pacemaker rate in isolated SAN cells and intact tissue. We investigated whether the Ca 2+ -sensitive nature of SK channels could explain arrhythmic SAN pacemaker activity in the atrial-specific Na + /Ca 2+ exchange (NCX) knockout (KO) mouse, a model of cellular Ca 2+ overload. SAN cells isolated from the NCX KO exhibited higher SK current than wildtype (WT) and apamin

Digoxin for atrial fibrillation and atrial flutter

DEFF Research Database (Denmark)

Sethi, Naqash J; Nielsen, Emil E; Safi, Sanam

2018-01-01

BACKGROUND: During recent years, systematic reviews of observational studies have compared digoxin to no digoxin in patients with atrial fibrillation or atrial flutter, and the results of these reviews suggested that digoxin seems to increase the risk of all-cause mortality regardless...... of concomitant heart failure. Our objective was to assess the benefits and harms of digoxin for atrial fibrillation and atrial flutter based on randomized clinical trials. METHODS: We searched CENTRAL, MEDLINE, Embase, LILACS, SCI-Expanded, BIOSIS for eligible trials comparing digoxin versus placebo......, no intervention, or other medical interventions in patients with atrial fibrillation or atrial flutter in October 2016. Our primary outcomes were all-cause mortality, serious adverse events, and quality of life. Our secondary outcomes were heart failure, stroke, heart rate control, and conversion to sinus rhythm...

Long-term effectiveness of surgical treatment of ectopic atrial tachycardia.

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Prager, N A; Cox, J L; Lindsay, B D; Ferguson, T B; Osborn, J L; Cain, M E

1993-07-01

The purpose of this study was to determine the long-term clinical outcome of patients with ectopic atrial tachycardias treated surgically. Ectopic atrial tachycardia is an uncommon arrhythmia that can be symptomatic and is associated with the development of a cardiomyopathy. Management strategies are not well defined because of the paucity of data on the long-term effectiveness of pharmacologic and nonpharmacologic therapies. The long-term clinical impact of medical and surgical therapy was determined in 15 consecutive patients with ectopic atrial tachycardia. All 15 patients were initially treated with antiarrhythmic drugs (mean 5.7 +/- 2.2 drugs/patient). An effective drug regimen was identified in only 5 (33%) of the 15 patients; the remaining 10 patients were treated surgically. In each, individualized surgical procedures were guided by computer-assisted intraoperative mapping, with atrial plaques comprising up to 156 electrodes. Focal ablation was performed in four patients and atrial isolation procedures in six. The 10 patients treated surgically were followed up a mean of 4 +/- 3.2 years. Ectopic atrial tachycardia recurred in one patient. A permanent pacemaker was implanted in two patients, one of whom also required reoperation for constrictive pericarditis. There were no operative deaths. Ectopic atrial tachycardia recurred in three (60%) of the five patients discharged on antiarrhythmic drug therapy during a mean follow-up interval of 6.4 +/- 4.3 years. There was one nonarrhythmic death. Map-guided surgery demonstrated long-term efficacy in abolishing symptoms in 9 of the 10 patients with ectopic atrial tachycardia. Results demonstrate that surgery is effective for patients with ectopic atrial tachycardias who are not easily treated with antiarrhythmic drugs.

Left atrial isolation associated with mitral valve operations.

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Graffigna, A; Pagani, F; Minzioni, G; Salerno, J; Viganò, M

1992-12-01

Surgical isolation of the left atrium was performed for the treatment of chronic atrial fibrillation secondary to valvular disease in 100 patients who underwent mitral valve operations. From May 1989 to September 1991, 62 patients underwent mitral valve operations (group I); 19, mitral valve operations and DeVega tricuspid annuloplasty (group II); 15, mitral and aortic operations (group III); and 4, mitral and aortic operations and DeVega tricuspid annuloplasty (group IV). Left atrial isolation was performed, prolonging the usual left paraseptal atriotomy toward the left fibrous trigone anteriorly and the posteromedial commissure posteriorly. The incision was conducted a few millimeters apart from the mitral valve annulus, and cryolesions were placed at the edges to ensure complete electrophysiological isolation of the left atrium. Operative mortality accounted for 3 patients (3%). In 79 patients (81.4%) sinus rhythm recovered and persisted until discharge from the hospital. No differences were found between the groups (group I, 80.7%; group II, 68.5%; group III, 86.7%; group IV, 75%; p = not significant). Three late deaths (3.1%) were registered. Long-term results show persistence of sinus rhythm in 71% of group I, 61.2% of group II, 85.8% of group III, and 100% of group IV. The unique risk factor for late recurrence of atrial fibrillation was found to be preoperative atrial fibrillation longer than 6 months. Due to the satisfactory success rate in recovering sinus rhythm, we suggest performing left atrial isolation in patients with chronic atrial fibrillation undergoing valvular operations.

Unexpected guest: Atrial fibrillation due to electrical shock

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Mehmet Zihni Bilik

2016-03-01

Full Text Available Cardiac arrhythmias due to electrical injuries are rare among emergency service admittances. A 35 year-old female patient was admitted to emergency service with palpitation after electrical injury as a result of contact with a domestic low-voltage source. Electrocardiography (ECG showed atrial fibrillation with rapid ventricular response. Transthoracic echocardiography findings were normal. Atrial fibrillation spontaneously converted to normal sinus rhythm after rate limiting treatment with beta-blocker. The patient was discharged without any complication on the third day of hospitalization. Although cardiac arrhythmias rarely occur after electrical injury, cardiac monitoring is recommended for all patients with documented rhythm disorder, loss of consciousness, or abnormal ECG at admission.

Effects of Prolonged Spaceflight on Atrial Size, Atrial Electrophysiology, and Risk of Atrial Fibrillation.

Science.gov (United States)

Khine, Htet W; Steding-Ehrenborg, Katarina; Hastings, Jeffrey L; Kowal, Jamie; Daniels, James D; Page, Richard L; Goldberger, Jeffery J; Ng, Jason; Adams-Huet, Beverley; Bungo, Michael W; Levine, Benjamin D

2018-05-01

The prevalence of atrial fibrillation (AF) in active astronauts is ≈5%, similar to the general population but at a younger age. Risk factors for AF include left atrial enlargement, increased number of premature atrial complexes, and certain parameters on signal-averaged electrocardiography, such as P-wave duration, root mean square voltage for the terminal 20 ms of the signal-averaged P wave, and P-wave amplitude. We aimed to evaluate changes in atrial structure, supraventricular beats, and atrial electrophysiology to determine whether spaceflight could increase the risk of AF. Thirteen astronauts underwent cardiac magnetic resonance imaging to assess atrial structure and function before and after 6 months in space and high-resolution Holter monitoring for multiple 48-hour time periods before flight, during flight, and on landing day. Left atrial volume transiently increased after 6 months in space (12±18 mL; P =0.03) without changing atrial function. Right atrial size remained unchanged. No changes in supraventricular beats were noted. One astronaut had a large increase in supraventricular ectopic beats but none developed AF. Filtered P-wave duration did not change over time, but root mean square voltage for the terminal 20 ms decreased on all fight days except landing day. No changes in P-wave amplitude were seen in leads II or V 1 except landing day for lead V 1 . Six months of spaceflight may be sufficient to cause transient changes in left atrial structure and atrial electrophysiology that increase the risk of AF. However, there was no definite evidence of increased supraventricular arrhythmias and no identified episodes of AF. © 2018 American Heart Association, Inc.

A Century of changes for Razelm-Sinoe Lagoon System

Science.gov (United States)

Scrieciu, Marian-Albert; Stanica, Adrian

2014-05-01

A Century of changes for Razelm-Sinoe Lagoon System Marian-Albert Scrieciu (a), Adrian Stanica (a) (a) National Institute of Marine Geology and Geoecology e GeoEcoMar, Str. Dimitrie Onciul 23e25, Sector 2, 024053 Bucharest, Romania Razelm-Sinoe Lagoon System, situated in the NW part of the Black Sea, in tight connection with the Danube Delta, has been subject to major changes due to human interventions in the past century. These changes have resulted into a complete change of the Lagoon specific ecosystems compared to its pristine state. In its natural state, as brackish - transitional environment, Antipa (1894) mentions Razelm Lagoon as one of the places with the greatest fisheries around the Black Sea coast (about 1879 - 1884, there were approximately 10,000 fishermen, all working on the Razelm Sinoe Lagoon System). Starting with the end of the XIXth Century, new canals were dug and existing channels were dredged in order to develop tighter connections with the Danube River. The natural inlet of Portita was blocked four decades ago and connections between the various parts of the lagoon system were controlled by the building of locks and sluices. The 2 inlets of Sinoe Lagoon were also controlled during early 1980s. Under these conditions, the lagoon ecosystem changed from brackish towards freshwater, with major effects on the existing flora and fauna. The period of brutal interventions ended in 1989 and the Razelm-Sinoe Lagoon System became part of the Danube Delta Biosphere Reserve in 1991, with a strict policy of nature protection and restoration. Spatial planning has been the major management option for the entire reserve, lagoon system included. Plans for sustainable development of the Razelm-Sinoe Lagoon System have been built in a participative manner, involving the local stakeholders, as part of FP7 ARCH project. Special attention has been given to impacts of climate change. The study presents the vision for the development Razelm-Sinoe Lagoon System over

[Late arrhythmias in the operated interatrial communication. Analysis of sinus node function and the conduction pathways by His bundle electrocardiography].

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Ramírez, A; Gil, M; Martínez Ríos, M A; Cárdenas, M; Pliego, J; Zamora, C; Mata, L A

1982-01-01

Four hundred patients with atrial septal defect treated surgically were reviewed. Thirty five (8.7%) developed arrhytmias post-surgery which persisted for over a year. Sinus bradycardia was found in 10 patients, nodal rhythm in 21, and atrial fibrilation and flutter in 4 patients. Thirty five per cent of the patients with late arrhythmias developed related symptomatology. In 14 patients the function of the sinus node was studied with electrical stimulation of the atrium and with His registry. The interatrial conduction time, AV node and His Purkinje were analized employing various stimulation frequencies. All the cases studied had normal intra-atrial conduction; the response of the atrio-ventricular node to increasing frequencies was normal, an the intraventricular conduction remained constant. In 8 patients (52%), alterations of the sinus node were found; these consisted of prolonged post-stimulation pauses, Wenckebach's type sinoatrial block and suppression of sinus automatism employing vagal procedures or through electrical stimulation. A patient with severe bradycardia detected by dynamic electrocardiography had to be treated with a permanent pacemaker. We confirm that these arrhytmias are not produced by lesions of the internodal tracts, and that an alteration of the sinus node is frequent without a concomitant lesion of the intraventricular pathway. The lesion to the nutrient artery could be due to trauma and/or surgically induced. The response to anticholinergic drugs was good. Prolonged observation of these patients could increase the morbility of these arrythmias and raise doubts of the surgical indications in cases with moderate hemodynamic repercussion.

A Therapeutic Challenge: Management of Atrial Thrombus

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Serkan Burc Deser

2016-09-01

Full Text Available Introduction: Primary cause of atrial thrombi include atrial fibrillation, foreign bodies inside the atrium such as catheters and pacemaker leads, emboli of deep venous thrombus and primary or metastatic tumors of the heart. We review the clinical features, epidemiology, diagnosis and treatment of nine intriguing cases with atrial thrombus. Methods: This is a retrospective study of nine patients (seven female (78%, two male (33% who were diagnosed with atrial thrombi (average age of 50 ± 12 years and were treated at the Ondokuz Mayis University, Department of Cardiovascular Surgery from February 2014 to January 2015. Among them, six patients had atrial fibrillation (one male, five female, seven patients were suffering from dispne and orthopnoea, five patients were suffering from leg swelling, seven patients had a history of hypertension and three patients had a history of mitral valve replacement surgery. Results: All patients underwent surgery except one. Four patients recovered uneventfully and discharged with oral anticoagulation (warfarin therapy (adjusted to maintain an international normalized ratio of INR between two and three times. Five of nine patients (55% died after surgery. Conclusion: The response to the thrombolytic therapy is poor, mostly ineffective and unsafe so it is often recommended as a bridge to surgery. In patients diagnosed with mechanical mitral valve thrombosis, medical therapy has the possibility of end organ emboli and also fail to resolve the organised thrombus on the stuck valve. On the other hand surgery does not always give satisfactory results. J Clin Exp Invest 2016; 7(4: 278-282

Organized Atrial Tachycardias after Atrial Fibrillation Ablation

Science.gov (United States)

Castrejón-Castrejón, Sergio; Ortega, Marta; Pérez-Silva, Armando; Doiny, David; Estrada, Alejandro; Filgueiras, David; López-Sendón, José L.; Merino, José L.

2011-01-01

The efficacy of catheter-based ablation techniques to treat atrial fibrillation is limited not only by recurrences of this arrhythmia but also, and not less importantly, by new-onset organized atrial tachycardias. The incidence of such tachycardias depends on the type and duration of the baseline atrial fibrillation and specially on the ablation technique which was used during the index procedure. It has been repeatedly reported that the more extensive the left atrial surface ablated, the higher the incidence of organized atrial tachycardias. The exact origin of the pathologic substrate of these trachycardias is not fully understood and may result from the interaction between preexistent regions with abnormal electrical properties and the new ones resultant from radiofrequency delivery. From a clinical point of view these atrial tachycardias tend to remit after a variable time but in some cases are responsible for significant symptoms. A precise knowledge of the most frequent types of these arrhythmias, of their mechanisms and components is necessary for a thorough electrophysiologic characterization if a new ablation procedure is required. PMID:21941669

Impact of Tricuspid Regurgitation on the Success of Atrioventricular Node Ablation for Rate Control in Patients With Atrial Fibrillation: The Node Blast Study.

Science.gov (United States)

Reddy, Yeruva Madhu; Gunda, Sampath; Vallakati, Ajay; Kanmanthareddy, Arun; Pillarisetti, Jayasree; Atkins, Donita; Bommana, Sudharani; Emert, Martin P; Pimentel, Rhea; Dendi, Raghuveer; Berenbom, Loren D; Lakkireddy, Dhanunjaya

2015-09-15

Atrioventricular node (AVN) ablation is an effective treatment for symptomatic patients with atrial arrhythmias who are refractory to rhythm and rate control strategies where optimal ventricular rate control is desired. There are limited data on the predictors of failure of AVN ablation. Our objective was to identify the predictors of failure of AVN ablation. This is an observational single-center study of consecutive patients who underwent AVN ablation in a large academic center. Baseline characteristics, procedural variables, and outcomes of AVN ablation were collected. AVN "ablation failure" was defined as resumption of AVN conduction resulting in recurrence of either rapid ventricular response or suboptimal biventricular pacing. A total of 247 patients drug refractory AF who underwent AVN ablation at our center with a mean age of 71 ± 12 years with 46% being males were included. Ablation failure was seen in 11 (4.5%) patients. There were no statistical differences between patients with "ablation failure" versus "ablation success" in any of the baseline clinical variables. Patients with moderate-to-severe tricuspid regurgitation (TR) were much more likely to have ablation failure than those with ablation success (8 [73%] vs 65 [27%]; p = 0.003). All 11 patients with ablation failure had a successful redo procedure, 9 with right and 2 with the left sided approach. On multivariate analysis, presence of moderate-to-severe TR was found to be the only predictor of failure of AVN ablation (odds ratio 9.1, confidence interval 1.99 to 42.22, p = 0.004). In conclusion, moderate-to-severe TR is a strong and independent predictor of failure of AVN ablation. Copyright © 2015 Elsevier Inc. All rights reserved.

Calculation of embodied energy in Sino-USA trade: 1997–2011

International Nuclear Information System (INIS)

Yang, Ranran; Long, Ruyin; Yue, Ting; Shi, Haihong

2014-01-01

In order to find efficient trade measures to reduce China's energy consumption and to provide theoretical support for the climate talks between China and America, we investigate the impact of Sino-USA trade on energy consumption from the perspective of embodied energy. An Environmental Input–Output Life Cycle Assessment (EIO-LCA) model was established to calculate the total energy consumption coefficient, the direct consumption coefficient and the complete consumption coefficient of the sectors of the national economies of China and America. After taking into consideration the data of every sector of the national economy in Sino-USA trade, energy embodied in the import and export trade between China and America was calculated to verify the real energy flows in Sino-USA trade. The research results suggest the following: China is the net exporter of embodied energy in Sino-USA trade, and coal, crude oil and natural gas are the major components. In 1997–2011, the net exports of China's embodied energy totaled 1523,082,200 t of standard coal, the amount of China's energy consumption increased by 895,527,900 t of standard coal, and America's energy consumption decreased by 11,871,200 t of standard coal as a result of Sino-USA trade. On this basis, corresponding policies and recommendations are proposed. - Highlights: • An EIO-LCA model is established to examine China's embodied energy in Sino-USA trade. • Embodied energy is calculated from the perspective of energy sources. • China is found to be the net exporter of embodied energy in Sino-USA trade. • Coal, crude oil and natural gas are the major components of China's net embodied energy exports. • China's energy consumption has increased and America's has shifted to China in Sino-USA trade

Atrial fibrillation in a healthy adolescent after heavy smoking of contraband cigarettes.

Science.gov (United States)

Ozyilmaz, Isa; Ozyilmaz, Sinem; Tosun, Oyku; Tola, Hasan Tahsin; Saygi, Murat; Ergul, Yakup

2015-08-01

The use of contraband cigarettes is a serious public health problem. We present a case of atrial fibrillation in a healthy adolescent suspected to be caused by smoking contraband cigarettes. A 15-year-old man was admitted to our emergency department experiencing syncope and palpitations. He was a cigarette smoker, but he had never smoked any illicit tobacco products before. He had finished a pack of counterfeit cigarettes (20 pieces) in 1.5 h. His electrocardiogram showed atrial fibrillation with a rapid ventricular response and irregular RR intervals. The patient had no history of alcohol use, surgery, palpitations, hypertension, chronic bronchitis, or any infectious diseases. His atrial fibrillation was converted to a normal sinus rhythm after the cardioversion treatment. Our patient was discharged from the pediatric cardiology service and advised to quit smoking cigarettes, strictly warning against illicit tobacco products. In conclusion, intensive smoking of counterfeit cigarettes may lead to occurrences of atrial fibrillation.

SECONDARY PREVENTION OF STROKE IN PATIENTS WITH NON-VALVULAR ATRIAL FIBRILLATION: THE CLINICIANS’ VIEWPOINT

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E. A. Drozdova

2015-09-01

Full Text Available Atrial fibrillation is one of the main risk factor of ischemic stroke. Current problems of the management of patients with stroke due to non-valvular atrial fibrillation and secondary stroke prevention in these patients are considered. Data of own author’s observation for patients of this type during 6 months after discharge from the hospital are presented. The problems which patients faced with are analyzed. Comparative assessment of warfarin and dabigatran therapies is given.

Atrial natriuretic peptide in patients with heart failure and chronic atrial fibrillation : Role of duration of at atrial fibrillation

NARCIS (Netherlands)

Van Den Berg, MP; Crijns, HJGM; Van Veldhuisen, DJ; Van Gelder, IC; De Kam, PJ; Lie, KI

The purpose of this study was to analyze the determinants of atrial natriuretic peptide level in patients with congestive heart failure and atrial fibrillation. In particular, the duration of atrial fibrillation was analyzed because atrial fibrillation per se might have a specific effect on atrial

A new therapeutic strategy for electrical cardioversion of atrial fibrillation.

Science.gov (United States)

de Luca, I; Sorino, M; Del Salvatore, B; de Luca, L

2001-11-01

The conventional approach to cardioversion of atrial fibrillation includes a period of anticoagulation with oral anticoagulant therapy (OAT) extending from 3 weeks precardioversion to 4 weeks postcardioversion. The protocol of rapid anticoagulation (such as that of the ACUTE study) consists of a precardioversion transesophageal echocardiography (TEE) followed by OAT for 4 weeks. In the last few years low-molecular-weight heparins have established themselves as a safe and efficacious alternative to traditional antithrombotic therapies. The aim of this study was to demonstrate that the exclusion of thrombi by precardioversion TEE together with the exclusion of atrial stunning by a second TEE performed after 1 week, to date not suggested in the literature, could reduce to 7 days the period of pericardioversion anticoagulation. This therapy would be carried out using low-molecular-weight heparins with no need for biological monitoring and with the possibility of self-administration. We have studied 57 consecutive patients who had atrial fibrillation or flutter with a history of atrial fibrillation lasting > 48 hours. All patients received enoxaparin at a dosage of 100 IU antiXa/kg twice daily before undergoing multiplane TEE. Previous informed consent and ethical committee authorization had been obtained. Twenty-four hours following TEE, in the absence of thrombi and/or spontaneous moderate/severe echocontrast in the atrial chambers, the patients underwent electrical cardioversion and were discharged within 24 hours of sinus rhythm restoration. These patients were prescribed enoxaparin at the indicated dosage twice daily until TEE, performed in an outpatients setting 7 days following cardioversion. In the absence of thrombi and/or atrial and/or left atrial appendage stunning, OAT was terminated. Enoxaparin was associated with OAT for the following 3 weeks if any of the following signs of stunning were present: A wave inferior to the normal value for age at transmitral

Language Choice of Urban Sino-Indians in Kuala Lumpur, Malaysia

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Maya Khemlani David

2008-09-01

Full Text Available Language choice in mixed marriages plays a crucial role in language maintenance. It helps in maintaining at least one or two languages from generation to generation. In this study an examination on the language choice of some Sino-Indian Malaysians in Kuala Lumpur, Malaysia, is explored to find out the language choice in a range of domains and with different speech partners. Sino-Indians are the offspring of marriages between Indians and Chinese. There were 30 participants consisting of 14 males and 16 females who took part in the study. A questionnaire consisting of 89 items was administered to the participants who were working or studying in Kuala Lumpur at that time. The findings reveal that language choice in some Sino-Indian families is influenced by factors such as age, domains of communication, attitudes towards the language, and identity. Age plays an important role in lan¬guage choice, particularly in the home domain. Some older Sino-Indian speakers are bilingual in English and Malay, the middle-aged speakers are trilingual and speak more in English and some Tamil and Chinese, and the younger speakers are multilingual but favour the use of English. This study has also examined how the Sino-Indian respondents viewed their dual heritage.

[The vulnerability of the human atrium. I. Correlations between vulnerability, sinus node recovery time and intraatrial conduction time (author's transl)].

Science.gov (United States)

Pop, T; Fleischmann, D; Effert, S

1976-09-01

Using the extrastimulus method in 100 patients, premature impulses were applied during the relative refractory period of the right atrium. Depending on the atrial response to these impulses we divided our patients in the following 3 groups: Group A: no repetitive firing (61 patients); group B: 1 to 5 additional atrial extrasystoles with a total duration of maximum 1.5 s (27 patients); group C: runs of atrial flutter or fibrilation for at least 8 s (12 patients). The statistical analysis of the following parameters: age, PA interval, absolute and corrected sinus node recovery time did not show any significant difference between the 3 groups. These results suggest that the investigated parameters are of no great importance in the genesis of the atrial vulnerability.

Atrial Fibrillation: Diagnosis

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... of this page please turn JavaScript on. Feature: Atrial Fibrillation Atrial Fibrillation: Diagnosis Past Issues / Winter 2015 Table of Contents ... of your body's cells and organs. Read More "Atrial Fibrillation" Articles Atrial Fibrillation / Who Is at Risk for ...

Impaired atrial electromechanical function and atrial fibrillation promotion in alloxan-induced diabetic rabbits.

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Fu, Huaying; Liu, Changle; Li, Jian; Zhou, Changyu; Cheng, Lijun; Liu, Tong; Li, Guangping

2013-01-01

Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). However, the underlying mechanisms are still not clearly elucidated. The aim of this study was to evaluate the atrial electromechanical function, atrial electrophysiological changes and AF inducibility in alloxan-induced diabetic rabbits. In 8 alloxan-induced diabetic rabbits and 8 controls, we evaluated atrial electromechanical function by tissue Doppler imaging. Isolated Langendorff-perfused rabbit hearts were prepared to measure atrial refractory effective period (AERP) and its dispersion (AERPD), interatrial conduction time (IACT) and vulnerability to AF. Atrial interstitial fibrosis was evaluated by Sirius-Red staining. Compared with controls, left atrial lateral wall Pa'-start interval (Pastart) and right atrial wall Pastart were increased in diabetic rabbits. AERPD was increased and IACT was prolonged in diabetic rabbits. Inducibility of AF in diabetic group was significant higher than controls (6/8 vs. 1/8, p TEMA); left atrial lateral wall Papeak and TEMA, left atrial posterior wall TEMA, and IACT were correlated with atrial areas of fibrosis. Atrial electromechanical function is impaired in diabetic rabbits, and is associated with atrial fibrosis and interatrial electrical conduction delay.

Prevalence, prognostic significance, and treatment of atrial fibrillation in congestive heart failure with particular reference to the DIAMOND-CHF study

DEFF Research Database (Denmark)

Pedersen, Ole Dyg; Brendorp, Bente; Køber, Lars

2003-01-01

Atrial fibrillation is a growing health problem and the most common cardiac arrhythmia, affecting 5% of persons above the age of 65 years. The number of hospital discharges for atrial fibrillation has more than doubled in the past decade. It occurs very often in patients with congestive heart...... failure and the prevalence increases with the severity of the disease. These two conditions seem to be linked together, and congestive heart failure may either be the cause or the consequence of atrial fibrillation. The prognosis of atrial fibrillation is controversial, but studies indicate that atrial...... fibrillation is a risk factor in congestive heart failure patients. In the last 10-15 years, significant advances in the treatment of heart failure have improved survival, whereas effective management of atrial fibrillation in heart failure patients still awaits similar progress. Empirically, two strategies...

Surgery for atrial fibrillation.

Science.gov (United States)

Viganò, M; Graffigna, A; Ressia, L; Minzioni, G; Pagani, F; Aiello, M; Gazzoli, F

1996-01-01

The mechanisms of atrial fibrillation arc multiple reentry circuits spinning around the atrial surface, and these baffle any attempt to direct surgical interruption. The purpose of this article is to report the surgical experience in the treatment of isolated and concomitant atrial fibrillation at the Cardiac Surgical Institute of the University of Pavia. In cases of atrial fibrillation secondary to mitral/valve disease, surgical isolation of the left atrium at the time of mitral valve surgery can prevent atrial fibrillation from involving the right atrium, which can exert its diastolic pump function on the right ventricle. Left atrial isolation was performed on 205 patients at the time of mitral valve surgery. Atrial partitioning ("maze operation") creates straight and blind atrial alleys so that non-recentry circuits can take place. Five patients underwent this procedure. In eight-cases of atrial fibrillation secondary to atrial septal defect, the adult patients with atrial septal defect and chronic or paroxysmal atrial fibrillation underwent surgical isolation of the right atrium associated which surgical correction of the defect, in order to let sinus rhythm govern the left atrium and the ventricles. "Lone" atrial fibrillation occurs in hearts with no detectable organic disease. Bi-atrial isolation with creation of an atrial septal internodal "corridor" was performed on 14 patients. In cases of atrial fibrillation secondary to mitral valve disease, left atrial isolation was performed on 205 patients at the time of mitral valve surgery with an overall sinus rhythm recovery of 44%. In the same period, sinus rhythm was recovered and persisted in only 19% of 252 patients who underwent mitral valve replacement along (P < 0.001). Sinus rhythm was less likely to recover in patients with right atriomegaly requiring tricuspid valve annuloplasty: 59% vs 84% (P < 0.001). Restoration of the right atrial function raised the cardiac index from 2.25 +/- 0.55 1/min per m2

Atrial Fibrillation in Eight New World Camelids.

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Bozorgmanesh, R; Magdesian, K G; Estell, K E; Stern, J A; Swain, E A; Griffiths, L G

2016-01-01

There is limited information on the incidence of clinical signs, concurrent illness and treatment options for atrial fibrillation (AF) in New World Camelids (NWC). Describe clinical signs and outcome of AF in NWC. Eight New World Camelids admitted with AF. A retrospective observational study of camelids diagnosed with AF based on characteristic findings on electrocardiogram (ECG). All animals had an irregularly irregular heart rhythm detected on physical examination and 4 cases had obtunded mentation on admission. Three camelids were diagnosed with AF secondary to oleander intoxication, 3 animals had underlying cardiovascular disease, 1 was diagnosed with lone AF and 1 had AF diagnosed on examination for a urethral obstruction. Five of eight animals survived to discharge and nonsurvivors consisted of animals which died or were euthanized as a result of cardiovascular disease (2/8) or extra-cardiac disease unrelated to the AF (1/8). Atrial fibrillation occurs in NWC in association with cardiovascular disease, extra-cardiac disease or as lone AF. Amiodarone and transthoracic cardioversion were attempted in one llama with lone AF, but were unsuccessful. Atrial fibrillation was recorded in 0.1% of admissions. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Atrial fibrillation: Therapeutic potential of atrial K+ channel blockers.

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Ravens, Ursula; Odening, Katja E

2017-08-01

Despite the epidemiological scale of atrial fibrillation, current treatment strategies are of limited efficacy and safety. Ideally, novel drugs should specifically correct the pathophysiological mechanisms responsible for atrial fibrillation with no other cardiac or extracardiac actions. Atrial-selective drugs are directed toward cellular targets with sufficiently different characteristics in atria and ventricles to modify only atrial function. Several potassium (K + ) channels with either predominant expression in atria or distinct electrophysiological properties in atria and ventricles can serve as atrial-selective drug targets. These channels include the ultra-rapidly activating, delayed outward-rectifying Kv1.5 channel conducting I Kur , the acetylcholine-activated inward-rectifying Kir3.1/Kir3.4 channel conducting I K,ACh , the Ca 2+ -activated K + channels of small conductance (SK) conducting I SK , and the two pore domain K + (K2P) channels TWIK-1, TASK-1 and TASK-3 that are responsible for voltage-independent background currents I TWIK-1 , I TASK-1 , and I TASK-3 . Here, we briefly review the characteristics of these K + channels and their roles in atrial fibrillation. The antiarrhythmic potential of drugs targeting the described channels is discussed as well as their putative value in treatment of atrial fibrillation. Copyright © 2016 Elsevier Inc. All rights reserved.

Echocardiography-guided Radiofrequency Catheter Ablation of Atrioventricular Node and VVI Pacemaker Implantation

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T Guo

2014-05-01

Full Text Available Objective: This study is to evaluate the feasibility and safety of intracardiac radiofrequency catheter ablation (RFCA of the atrioventricular node (AVN and pacemaker implantation using transthoracic echocardiography. Methods: Eleven patients – six males and five females (mean age 66 years – with persistent or permanent atrial fibrillation/atrial flutter received RFCA of AVN and VVI pacemaker implantation (paces and senses the ventricle and is inhibited if it senses ventricular activity. Under transthoracic echocardiography, the electrode catheters were positioned intracardiac, and target ablation was performed, with the permanent pacemaking catheter in the left subclavian vein and the ablation catheter in the right femoral vein. The multi-view imaging and dynamic observation applied during the stable AV dissociation were successful. Results: Atrioventricular node ablation and permanent pacemaker implantation in 11 patients were completed successfully without X-ray exposure. The operation success rate was 100%. All patients recovered well within the follow-up period. Conclusions: Radiofrequency catheter ablation of AVN and VVI pacemaker implantation under transthoracic echocardiography guidance is a safe, easy and feasible approach. This procedure could be an important supplemental measure to catheter ablation of arrhythmia under routine X-ray fluoroscopy.

Sino-American Corporation in Peru

Institute of Scientific and Technical Information of China (English)

Wang Mingcai; Xu Yunming

1996-01-01

@@ Sino-American Oil Development Corporation (hereinafter referred to as"SODC") has taken part in the international operation activities in petroleum exploration and development in Latin-American area since 1992 and some progress has been made. At present, SODC is carrying out the operations within the Sixth and Seventh Blocks of Tarara oil field of the Republic of Peru and gains a good prestige.

Atrial Fibrillation: Treatment

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... of this page please turn JavaScript on. Feature: Atrial Fibrillation Atrial Fibrillation: Treatment Past Issues / Winter 2015 Table of Contents Treatment for atrial fibrillation depends on how often you have symptoms, how ...

Importância da anatomia da circulação coronária atrial na operação de Cox para controle da fibrilação atrial The importance of atrial coronary circulation on Cox surgery for control atrial fibrillation

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Marcelo B. JATENE

1999-01-01

Full Text Available Com o advento de novas técnicas cirúrgicas para o tratamento das arritmias cardíacas, em especial da fibrilação atrial, como a cirurgia de Cox, o conhecimento das características e do trajeto das artérias coronárias atriais assumiu grande importância. O objetivo deste trabalho é o estudo desta circulação e a definição dos padrões de irrigação atrial. Para tanto, utilizamos 30 corações a fresco de indivíduos sem cardiopatia prévia, cujas artérias coronárias e ramos foram visibilizados através de injeção de resina vinílica corada com tinta laca preta, seguida de cuidadosa dissecção. Após avaliação macroscópica das peças, não foram encontrados padrões de irrigação uniforme dos átrios. Porém, a artéria do nó sinoatrial (ANSA, quando analisada isoladamente, revelou não apenas padrões de origem, como também padrões de trajeto. Foram descritos 7 padrões de origem e trajeto da ANSA, considerando-se pontos de referências da estrutura anatômica dos átrios. Os padrões descritos, diferente dos encontrados por outros autores, são de fácil interpretação e de aplicabilidade direta em técnicas cirúrgicas que abordam os átrios.Since the appearance of new surgical techniques such as Cox surgery employed for the treatment of cardiac arrhythmia, especially for atrial fibrillation, the knowledge of coronary artery characteristics and courses has been of increasing importance. The aim of this study was the analysis of this circulation and definition of atrial irrigation patterns. Hence, the coronary arteries of 30 normal human hearts were injected with colored resin and carefully dissected. After macroscopic evaluation of the hearts, no atrial irrigation patterns were found. However, when only the sinus atrial node was analyzed, it showed origin patterns as well as course patterns. Seven origin and route patterns of this artery are described, considering the anatomical structure of the atria as reference

[Left versus bi-atrial radiofrequency ablation in the treatment of atrial fibrillation].

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Wang, Jian-Gang; Meng, Xu; Li, Hui

2008-11-25

To evaluate the effectiveness of radiofrequency modified maze operation for the treatment of atrial fibrillation (AF) and compare the results of the left versus bi-atrial procedures. 305 patients of organic heart disease combined with AF, 117 males and 188 females, aged (53 +/- 10), that underwent cardiac valve operation (n = 293) and/or coronary artery bypass graft surgery (n = 14), received concomitant atrial fibrillation, bi-atrial (n = 160) or left atrial (n = 145) with a mean duration of (36 +/- 43) months. Follow-up was conducted for (28 +/- 5) (3 - 42) months. Thirteen patients (4.3%) died postoperatively: 7 died of multisystem and organ failure, 3 of low cardiac output, 1 of rupture of left ventricle, 1 of arrhythmia, and 1 of sudden death. During the follow-up, 1 patient died of heart failure, 1 of encephalorrhagia and 1 of unknown reason in the bi-atrial group. At the end of the procedure 223 patients (73.1%) had sinus rhythm, with a sinus rhythm rate of 66.9% (107/160) in the bi-atrial group, significant lower than that in the left atrial group (80.0%, 116/145, P bi-atrial group was 80.0%, not significantly different from that of the left atrial group (81.9%, P > 0.05). The Kaplan-Meier survival analysis showed there was no significant difference in the AF rhythm rate between these 2 groups (P = 0.33). Logistic regression analysis showed that the left atrial diameter of >/= 80 mm was an independent predictor of AF recurrence. Both the left and bi-atrial procedures are successful in terms of restoring sinus rhythm. Left atrial ablation in severe cases and where the incision of right atrium is not needed is a reasonable choice.

Estudo randomizado de correção cirúrgica de fibrilação atrial permanente: resultados parciais Randomized study of surgical correction of permanent atrial fibrillation: preliminary results

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Álvaro Albrecht

2004-09-01

Full Text Available OBJETIVO: Analisar os resultados de dois modos de tratar a fibrilação atrial (FA: com cirurgia do Labirinto e com Isolamento de Veias Pulmonares (IVP, comparando com grupo controle, para estabelecer o melhor tratamento aos portadores desta arritmia. MÉTODO:Todos os pacientes tinham indicação cirúrgica por outra lesão cardíaca, concomitantemente tratada. Foram randomizados 51 pacientes no período de julho de 1999 a setembro de 2003. Em nenhum paciente foi utilizada crioablação. Analisamos inicialmente as seguintes variáveis: tempo de circulação extracorpórea (CEC, pinçamento aórtico (ISQ, taxa de reversão a ritmo sinusal na alta hospitalar, e complicações do trans e pós-operatório imediato. RESULTADOS: Houve dois óbitos intra-hospitalares, um no grupo Labirinto e um no grupo IVP. O grupo Labirinto apresentou o maior tempo de CEC (pOBJECTIVE: To analyze the results of techniques in the treatment of atrial fibrillation: the Maze procedure and Isolation of Pulmonary Veins were compared together with Control group, to establish the best treatment for this arrhythmia. METHOD: All patients were referred for surgery due for other cardiac lesions, which were treated concurrently. From July 1999 to September 2003, fifty-one patients where randomly allocated to the different groups. No cryoablation or other source of energy was used. The following variables were initially analyzed: total bypass time, aortic clamping time, sinus rhythm at discharge, and trans-operative and immediate post-operative complications. RESULTS: There were two intra-hospitalar deaths, one in the Maze group and one in the Isolation of Pulmonary Veins group. The Maze group had the longest bypass time (p<0,001. The duration of follow-up of 28.4 ±14 months was similar between the groups. The Isolation of Pulmonary Veins achieved the best results concerning reversion to sinus rhythm with 84.2% at hospital discharge and 88.9% after follow-up. In the Maze group, 78

Relevance of Electrical Remodeling in Human Atrial Fibrillation Results of the Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial Mechanisms of Atrial Fibrillation Study

NARCIS (Netherlands)

Healey, Jeff S.; Israel, Carsten W.; Connolly, Stuart J.; Hohnloser, Stefan H.; Nair, Girish M.; Divakaramenon, Syamkumar; Capucci, Alessandro; Van Gelder, Isabelle C.; Lau, Chu-Pak; Gold, Michael R.; Carlson, Mark; Themeles, Ellison; Morillo, Carlos A.

Background-In animal models of atrial fibrillation (AF), changes in atrial electrophysiological properties are associated with the development of AF. Their relevance to human AF is unclear. Methods and Results-The Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the

Increased amount of atrial fibrosis in patients with atrial fibrillation secondary to mitral valve disease

NARCIS (Netherlands)

Geuzebroek, Guillaume S. C.; van Amersfoorth, Shirley C. M.; Hoogendijk, Mark G.; Kelder, Johannes C.; van Hemel, Norbert M.; de Bakker, Jacques M. T.; Coronel, Ruben

2012-01-01

Objective: Atrial fibrosis is related to atrial fibrillation but may differ in patients with mitral valve disease or lone atrial fibrillation. Therefore, we studied atrial fibrosis in patients with atrial fibrillation + mitral valve disease or with lone atrial fibrillation and compared it with

Smartphone electrographic monitoring for atrial fibrillation in acute ischemic stroke and transient ischemic attack.

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Tu, Hans T; Chen, Ziyuan; Swift, Corey; Churilov, Leonid; Guo, Ruibing; Liu, Xinfeng; Jannes, Jim; Mok, Vincent; Freedman, Ben; Davis, Stephen M; Yan, Bernard

2017-10-01

Rationale Paroxysmal atrial fibrillation is a common and preventable cause of devastating strokes. However, currently available monitoring methods, including Holter monitoring, cardiac telemetry and event loop recorders, have drawbacks that restrict their application in the general stroke population. AliveCor™ heart monitor, a novel device that embeds miniaturized electrocardiography (ECG) in a smartphone case coupled with an application to record and diagnose the ECG, has recently been shown to provide an accurate and sensitive single lead ECG diagnosis of atrial fibrillation. This device could be used by nurses to record a 30-s ECG instead of manual pulse taking and automatically provide a diagnosis of atrial fibrillation. Aims To compare the proportion of patients with paroxysmal atrial fibrillation detected by AliveCor™ ECG monitoring with current standard practice. Sample size 296 Patients. Design Consecutive ischemic stroke and transient ischemic attack patients presenting to participating stroke units without known atrial fibrillation will undergo intermittent AliveCor™ ECG monitoring administered by nursing staff at the same frequency as the vital observations of pulse and blood pressure until discharge, in addition to the standard testing paradigm of each participating stroke unit to detect paroxysmal atrial fibrillation. Study outcome Proportion of patients with paroxysmal atrial fibrillation detected by AliveCor™ ECG monitoring compared to 12-lead ECG, 24-h Holter monitoring and cardiac telemetry. Discussion Use of AliveCor™ heart monitor as part of routine stroke unit nursing observation has the potential to be an inexpensive non-invasive method to increase paroxysmal atrial fibrillation detection, leading to improvement in stroke secondary prevention.

Atrial Fibrillation: Complications

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... of this page please turn JavaScript on. Feature: Atrial Fibrillation Atrial Fibrillation: Complications Past Issues / Winter 2015 Table of Contents ... has two major complications—stroke and heart failure. Atrial Fibrillation and Stroke Click to enlarge image This illustration ...

SPECIAL CONSIDERATIONS REGARDING WARFARIN DOSE TITRATION IN PATIENTS WITH ATRIAL FIBRILLATION DEPENDING ON CLINICAL FACTORS

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E. L. Artanova

2011-01-01

Full Text Available Aim. To study the relations of clinical characteristics and individual warfarin dose titration in patients with atrial fibrillation. Material and methods. Period of warfarin dose titration was analyzed in 68 patients with atrial fibrillation due to ischemic heart disease. Adjusted warfarin dose in milligram, duration of dose titration in days and maximal international normalized ratio (INR were taken into account. Sex, age, history of myocardial infarction and stroke, concomitant diseases, amiodarone therapy were considered among clinical characteristics. Results. Adjusted warfarin dose was significantly higher in obesity , and it was lower in case of experienced myocardial infarction. The INR highest levels and maximal amplitudes of its fluctuations were observed in patients with thyroid gland nodes and smokers. Period of warfarin dose titration was longer in patients treated with amiodarone. Conclusion. Warfarin dose titration in patients with atrial fibrillation depends on the presence of myocardial infarction, obesity , thyroid nodular changes, smoking and amiodarone treatment.

Isthmus Dependent Atrial Flutter Cycle Length Correlates with Right Atrial Cross-Sectional Area

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Kousik Krishnan

2009-05-01

Full Text Available Background: Right atrial flutter cycle length can prolong in the presence of antiarrhythmic drug therapy. We hypothesized that the cycle length of right atrial isthmus dependent flutter would correlate with right atrial cross-sectional area measurements. Methods: 60 patients who underwent ablation for electrophysiologically proven isthmus dependent right atrial flutter, who were not on Class I or Class III antiarrhythmic drugs and had recent 2-dimensional echocardiographic data comprised the study group. Right atrial length and width were measured in the apical four chamber view. Cross-sectional area was estimated by multiplying the length and width. 35 patients had an atrial flutter rate ≥250 bpm (Normal Flutter Group and 25 patients had an atrial flutter rate < 250 bpm (Slow Flutter Group. Results: Mean atrial flutter rate was 283 bpm in the normal flutter group and 227 bpm in the slow flutter group. Mean atrial flutter cycle length was 213 ms in the Normal Flutter Group and 265 ms in the Slow Flutter Group (p<0.0001. Mean right atrial cross sectional area was 1845 mm2 in the Normal Flutter group and 2378 mm2 in the Slow Flutter Group, (p< 0.0001. Using linear regression, CSA was a significant predictor of cycle length (β =0.014 p = 0.0045. For every 1 mm2 increase in cross-sectional area, cycle length is 0.014 ms longer.Conclusion: In the absence of antiarrhythmic medications, right atrial cross sectional area enlargement correlates with atrial flutter cycle length. These findings provide further evidence that historical rate-related definitions of typical isthmus dependent right atrial are not mechanistically valid.

Superior transseptal approach to mitral valve is associated with a higher need for pacemaker implantation than the left atrial approach

DEFF Research Database (Denmark)

Lukac, Peter; Hjortdal, Vibeke E; Pedersen, Anders K

2006-01-01

retrospectively evaluated. The surgeons used either the superior transseptal (group A) or left atrial approach (group B). The risk of pacemaker implantation associated with the superior transseptal approach as compared with the left atrial approach was estimated using the multivariate Cox regression analysis...... to adjust for possible confounders. RESULTS: We included 577 patients, 150 in group A and 427 in group B. Forty-four patients had a pacemaker implanted after the surgery; 17 in group A and 27 in group B (p = 0.010). The superior transseptal approach was an independent risk factor of pacemaker implantation...... in multivariate analysis (hazard ratio 2.2 [1.2 to 4.1], p = 0.014). Nineteen patients had a pacemaker implanted because of sinus node dysfunction; 9 in group A and 10 in group B (p = 0.017). Group A was an independent predictor of pacemaker implantation because of sinus node dysfunction in bivariate analyses...

Changes in plasma atrial natriuretic factor in patients with idiopathic atrial fibrillation

International Nuclear Information System (INIS)

Du Tongxin; Xia Xiaojie; Qu Wei; Wang Shukui; Sun Junjiang

2002-01-01

To observe the changes in plasma atrial natriuretic factor (AFN) in patients with idiopathic atrial fibrillation and investigate its mechanism, plasma ANF, platelet count and hematocrit were detected in 21 cases with transient idiopathic atrial fibrillation (group A, A1 representing attack, while A2 termination), 28 with persistent idiopathic atrial fibrillation (group B), 27 suffered from rheumatic heart disease with mitral stenosis and persistent atrial fibrillation (group C), 32 with transient supraventricular tachycardia (group D) and 20 normal controls (group E). It was found that the level of ANF was significantly higher in patients with attacking transient idiopathic atrial fibrillation than that in group A2, D and E (P 0.05), while there was significant difference in hematocrit in group A1 compared with group A2, D, E (P < 0.01). It suggested that ANF and hematocrit play an important role in the attack of idiopathic atrial fibrillation

Atrial and ventricular function after cardioversion of atrial fibrillation.

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Xiong, C.; Sonnhag, C.; Nylander, E.; Wranne, B.

1995-01-01

OBJECTIVE--Previous studies on atrial recovery after cardioversion of atrial fibrillation have not taken into account new knowledge about the pathophysiology of transmitral and transtricuspid flow velocity patterns. It is possible to shed further light on this problem if atrioventricular inflow velocity, venous filling pattern, and atrioventricular annulus motion are recorded and interpreted together. DESIGN--Prospective examinations of mitral and tricuspid transvalvar flow velocities, superior caval and pulmonary venous filling, and mitral and tricuspid annulus motion were recorded using Doppler echocardiography. Examinations were performed before and 24 hours, 1 month, and 20 months after cardioversion. SETTING--Tertiary referral centre for cardiac disease with facilities for invasive and non-invasive investigation. PATIENTS--16 patients undergoing cardioversion of atrial fibrillation in whom sinus rhythm had persisted for 24 hours or more. RESULTS--Before conversion there was no identifiable A wave in transvalvar flow recordings. The total motion of the tricuspid and mitral annulus was subnormal and there was no identifiable atrial component. Venous flow patterns in general showed a low systolic velocity. After conversion, A waves and atrial components were seen in all patients and increased significantly (P atrial components, an increased systolic component of venous inflow, an increased A wave velocity, and a decreased E/A ratio of the transvalvar velocity curves. The ventricular component of annulus motion was unchanged. Changes in general occurred earlier on the right side than the left. CONCLUSIONS--This study indicates that, in addition to the previously known electromechanical dissociation of atrial recovery that exists after cardioversion of atrial fibrillation, there may also be a transient deterioration of ventricular function modulating the transvalvar inflow velocity recordings. Function on the right side generally becomes normal earlier than on the

The contemporary dynamics of Sino-Indian relations: Examining maritime security, economics, energy and elite dialogue

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Athwal, Amardeep

This dissertation examines the modern-day dynamics of the Sino-Indian relationship---with a particular focus on issues relating to maritime security, economics, energy and elite bilateral dialogue. In exploring the contemporary nature of the Sino-Indian relationship, the dissertation also seeks to assess the accuracy of predominant neorealist accounts of the Sino-Indian relationship. Since the 1962 Sino-Indian War, most analysts have continued to emphasize the conflictual and competitive elements within the Sino-Indian relationship. The dissertation first explores the crucial post-independence history of Sino-Indian relations to provide the appropriate contextual background (chapter one). Thereafter, the dissertation explores the geopolitical significance of the Indian Ocean in light of soaring (global) energy demands. This then leads into an analysis of China and India's naval modernization and China's strategic partnership with Pakistan and Myanmar (chapter two). While acknowledging the credibility of neorealist insights in the realm of maritime security by detailing China and India's naval buildup and naval strategy, overall, it is found that the security dilemma argument is overstated. There is both a lack of threat perception and the existence of alternate explanations for both Chinese and Indian activities in Southern Asia. The dissertation then moves on to explore the positive elements within the Sino-Indian relationship---growing economic interdependence, energy convergence and elite consensus. In the economic realm (chapter three) it is found that Sino-Indian bilateral trade is increasingly being framed institutionally and rapidly expanding every year. The areas where the Sino-Indian economic relationship could be fruitfully expanded are traced and the great potential of bilateral trade is discussed. Thereafter, the dissertation highlights how China and India are beginning to coordinate energy policy (chapter four) as well as the growing political will

Evaluating the Atrial Myopathy Underlying Atrial Fibrillation: Identifying the Arrhythmogenic and Thrombogenic Substrate

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Goldberger, Jeffrey J.; Arora, Rishi; Green, David; Greenland, Philip; Lee, Daniel C.; Lloyd-Jones, Donald M.; Markl, Michael; Ng, Jason; Shah, Sanjiv J.

2015-01-01

Atrial disease or myopathy forms the substrate for atrial fibrillation (AF) and underlies the potential for atrial thrombus formation and subsequent stroke. Current diagnostic approaches in patients with AF focus on identifying clinical predictors with evaluation of left atrial size by echocardiography serving as the sole measure specifically evaluating the atrium. Although the atrial substrate underlying AF is likely developing for years prior to the onset of AF, there is no current evaluation to identify the pre-clinical atrial myopathy. Atrial fibrosis is one component of the atrial substrate that has garnered recent attention based on newer MRI techniques that have been applied to visualize atrial fibrosis in humans with prognostic implications regarding success of treatment. Advanced ECG signal processing, echocardiographic techniques, and MRI imaging of fibrosis and flow provide up-to-date approaches to evaluate the atrial myopathy underlying AF. While thromboembolic risk is currently defined by clinical scores, their predictive value is mediocre. Evaluation of stasis via imaging and biomarkers associated with thrombogenesis may provide enhanced approaches to assess risk for stroke in patients with AF. Better delineation of the atrial myopathy that serves as the substrate for AF and thromboembolic complications might improve treatment outcomes. Furthermore, better delineation of the pathophysiologic mechanisms underlying the development of the atrial substrate for AF, particularly in its earlier stages, could help identify blood and imaging biomarkers that could be useful to assess risk for developing new onset AF and suggest specific pathways that could be targeted for prevention. PMID:26216085

The role of atrial fibrillation on mortality and morbidity in patients with ischaemic stroke.

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Cögen, Etem Emre; Tombul, Temel; Yildirim, Gökhan; Odabas, Faruk Omer; Sayin, Refah

2013-12-01

To investigate the impact of atrial fibrillation on mortality and morbidity in ischaemic stroke patients. The retrospective study was conducted at the Neurology Clinic, Faculty of Medicine, Yuzuncu Yil University, Van, Turkey, and comprised records of ischaemic stroke patients hospitalised between January 2006 and September 2009. SPSS 13 was used for statistical analysis. Of the 404 patients in the study, 69 (17.1%) had atrial fibrilation. The mean age of such patients was 66.78 +/- 12.23 years compared to 61.01 +/- 15.11 years for the rest. Besides 47 (68.1%) of these patients were females. According to the modified Rankin Scale scores, the degree of disability was significantly higher at the time of arrival and discharge, and mortality rates were significantly higher also (p Atrial fibrillation affected the prognosis of ischaemic stroke adversely in terms of mortality and morbidity.

Sino-Japanese Relations: Cooperation, Competition, or Status Quo?

National Research Council Canada - National Science Library

Taylor, Fred H

2008-01-01

Over the course of their history, bilateral Sino-Japanese relations have experienced a paradoxical relationship of autonomy and interdependence, mutual respect and suspicion, and admiration and condescension...

Antiarrhythmic properties of atrial pacing.

Science.gov (United States)

Kliś, Magdalena; Sławuta, Agnieszka; Gajek, Jacek

2017-01-01

Bradycardia, atrial stretch and dilatation, autonomic nervous system disorders, and the presence of triggers such as atrial premature contractions, are factors which predispose a person to paroxysmal AF. Atrial pacing not only eliminates bradycardia but also prevents atrial premature contractions and dispersion of refractoriness, which are a substrate for atrial fibrillation. As the prolonged duration of atrial activation during pacing, especially from locations changing the physiological pattern of this activation (right atrium lateral wall, right atrium appendage), negatively influences both a mechanical and an electrical function of the atria, the atrial pacing site affects an atrial arrhythmogenesis. A conventional atrial lead location in the right atrium appendage causes non-physiological activation propagation, resulting in a prolongation of the activation time of both atria. This location is optimal according to a passive fixation of the atrial lead but the available contemporary active fixation leads could potentially be located in any area of the atrium. There is growing evidence of the benefit of pacing, imitating the physiological propagation of impulses within the atria. It seems that the Bachmann's bundle pacing is the best pacing site within the atria, not only positively influencing the atrial mechanical function but also best fulfilling the so-called atrial resynchronization function, in particular in patients with interatrial conduction delay. It can be effectively achieved using only one atrial electrode, and the slight shortening of atrioventricular conduction provides an additional benefit of this atrial pacing site.

76 FR 5626 - Notice and Opportunity for Hearing: SinoFresh Healthcare, Inc.

Science.gov (United States)

2011-02-01

... SECURITIES AND EXCHANGE COMMISSION [Release No. 34-63776; File No. 0-49764] Notice and Opportunity for Hearing: SinoFresh Healthcare, Inc. January 26, 2011 Notice is hereby given that on November 1, 2010, SinoFresh Healthcare, Inc. (Applicant) filed with the Securities and Exchange Commission a Form...

Basic Relationships among Scale, Quality, and Benefits in Sino-Foreign Cooperative Education

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Lin, Jinhui

2016-01-01

The basic relationships among scale, quality, and benefits in Sino-foreign cooperative education are key to the development of cooperative education. It is necessary to construct a theoretical framework for the basic relationships among scale, quality, and benefits in Sino-foreign cooperative education and analyze the questions faced in…

Atrialización de un caso de síndrome de aurícula paralítica Atrialization in one case of atrial palsy syndrome

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Alejandro Orjuela

recurrent syncope, who had received in the past a definitive single chamber pacemaker implant, is presented. Inflammatory heart diseases, muscular dystrophies and other secondary causes of his sinus impulse disorder were ruled out. An atrial electrophysiological study during the programmed change of the generator was performed, just before one of the pacemaker‘s batteries began to discharge. No mayor activity was found. An atrial electrode was implanted and echocardiographic follow-up of the auricular function was performed, showing a discrete improvement six months after the implant and then returning to the basal values, reason by which the atrial channel was turned off. Although some patients regain atrial function after cardioversion for atrial fibrillation, the percentage of patients that could do it after atrial stimulation in a little mechanically and electrically active auricle, is unknown. Therefore, the measurement of atrial activity and the stimulation before deciding the implant of an atrial electrode are very useful.

Increasing Prevalence of Atrial Fibrillation and Permanent Atrial Arrhythmias in Congenital Heart Disease.

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Labombarda, Fabien; Hamilton, Robert; Shohoudi, Azadeh; Aboulhosn, Jamil; Broberg, Craig S; Chaix, Marie A; Cohen, Scott; Cook, Stephen; Dore, Annie; Fernandes, Susan M; Fournier, Anne; Kay, Joseph; Macle, Laurent; Mondésert, Blandine; Mongeon, François-Pierre; Opotowsky, Alexander R; Proietti, Anna; Rivard, Lena; Ting, Jennifer; Thibault, Bernard; Zaidi, Ali; Khairy, Paul

2017-08-15

Atrial arrhythmias are the most common complication encountered in the growing and aging population with congenital heart disease. This study sought to assess the types and patterns of atrial arrhythmias, associated factors, and age-related trends. A multicenter cohort study enrolled 482 patients with congenital heart disease and atrial arrhythmias, age 32.0 ± 18.0 years, 45.2% female, from 12 North American centers. Qualifying arrhythmias were classified by a blinded adjudicating committee. The most common presenting arrhythmia was intra-atrial re-entrant tachycardia (IART) (61.6%), followed by atrial fibrillation (28.8%), and focal atrial tachycardia (9.5%). The proportion of arrhythmias due to IART increased with congenital heart disease complexity from 47.2% to 62.1% to 67.0% in patients with simple, moderate, and complex defects, respectively (p = 0.0013). Atrial fibrillation increased with age to surpass IART as the most common arrhythmia in those ≥50 years of age (51.2% vs. 44.2%; p congenital heart disease, with a predominantly paroxysmal pattern. However, atrial fibrillation increases in prevalence and atrial arrhythmias progressively become permanent as the population ages. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Left Atrial 4D Blood Flow Dynamics and Hemostasis following Electrical Cardioversion of Atrial Fibrillation

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Merih Cibis

2017-12-01

Full Text Available Background: Electrical cardioversion in patients with atrial fibrillation is followed by a transiently impaired atrial mechanical function, termed atrial stunning. During atrial stunning, a retained risk of left atrial thrombus formation exists, which may be attributed to abnormal left atrial blood flow patterns. 4D Flow cardiovascular magnetic resonance (CMR enables blood flow assessment from the entire three-dimensional atrial volume throughout the cardiac cycle. We sought to investigate left atrial 4D blood flow patterns and hemostasis during left atrial stunning and after left atrial mechanical function was restored.Methods: 4D Flow and morphological CMR data as well as blood samples were collected in fourteen patients at two time-points: 2–3 h (Time-1 and 4 weeks (Time-2 following cardioversion. The volume of blood stasis and duration of blood stasis were calculated. In addition, hemostasis markers were analyzed.Results: From Time-1 to Time-2: Heart rate decreased (61 ± 7 vs. 56 ± 8 bpm, p = 0.01; Maximum change in left atrial volume increased (8 ± 4 vs. 22 ± 15%, p = 0.009; The duration of stasis (68 ± 11 vs. 57 ± 8%, p = 0.002 and the volume of stasis (14 ± 9 vs. 9 ± 7%, p = 0.04 decreased; Thrombin-antithrombin complex (TAT decreased (5.2 ± 3.3 vs. 3.3 ± 2.2 μg/L, p = 0.008. A significant correlation was found between TAT and the volume of stasis (r2 = 0.69, p < 0.001 at Time-1 and between TAT and the duration of stasis (r2 = 0.34, p = 0.04 at Time-2.Conclusion: In this longitudinal study, left atrial multidimensional blood flow was altered and blood stasis was elevated during left atrial stunning compared to the restored left atrial mechanical function. The coagulability of blood was also elevated during atrial stunning. The association between blood stasis and hypercoagulability proposes that assessment of left atrial 4D flow can add to the pathophysiological understanding of thrombus formation during atrial fibrillation

Left Atrial 4D Blood Flow Dynamics and Hemostasis following Electrical Cardioversion of Atrial Fibrillation

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Cibis, Merih; Lindahl, Tomas L.; Ebbers, Tino; Karlsson, Lars O.; Carlhäll, Carl-Johan

2017-01-01

Background: Electrical cardioversion in patients with atrial fibrillation is followed by a transiently impaired atrial mechanical function, termed atrial stunning. During atrial stunning, a retained risk of left atrial thrombus formation exists, which may be attributed to abnormal left atrial blood flow patterns. 4D Flow cardiovascular magnetic resonance (CMR) enables blood flow assessment from the entire three-dimensional atrial volume throughout the cardiac cycle. We sought to investigate left atrial 4D blood flow patterns and hemostasis during left atrial stunning and after left atrial mechanical function was restored. Methods: 4D Flow and morphological CMR data as well as blood samples were collected in fourteen patients at two time-points: 2–3 h (Time-1) and 4 weeks (Time-2) following cardioversion. The volume of blood stasis and duration of blood stasis were calculated. In addition, hemostasis markers were analyzed. Results: From Time-1 to Time-2: Heart rate decreased (61 ± 7 vs. 56 ± 8 bpm, p = 0.01); Maximum change in left atrial volume increased (8 ± 4 vs. 22 ± 15%, p = 0.009); The duration of stasis (68 ± 11 vs. 57 ± 8%, p = 0.002) and the volume of stasis (14 ± 9 vs. 9 ± 7%, p = 0.04) decreased; Thrombin-antithrombin complex (TAT) decreased (5.2 ± 3.3 vs. 3.3 ± 2.2 μg/L, p = 0.008). A significant correlation was found between TAT and the volume of stasis (r2 = 0.69, p < 0.001) at Time-1 and between TAT and the duration of stasis (r2 = 0.34, p = 0.04) at Time-2. Conclusion: In this longitudinal study, left atrial multidimensional blood flow was altered and blood stasis was elevated during left atrial stunning compared to the restored left atrial mechanical function. The coagulability of blood was also elevated during atrial stunning. The association between blood stasis and hypercoagulability proposes that assessment of left atrial 4D flow can add to the pathophysiological understanding of thrombus formation during atrial fibrillation related

Expression and distribution of voltage-gated ion channels in ferret sinoatrial node.

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Brahmajothi, Mulugu V; Morales, Michael J; Campbell, Donald L; Steenbergen, Charles; Strauss, Harold C

2010-10-01

Spontaneous diastolic depolarization in the sinoatrial (SA) node enables it to serve as pacemaker of the heart. The variable cell morphology within the SA node predicts that ion channel expression would be heterogeneous and different from that in the atrium. To evaluate ion channel heterogeneity within the SA node, we used fluorescent in situ hybridization to examine ion channel expression in the ferret SA node region and atrial appendage. SA nodal cells were distinguished from surrounding cardiac myocytes by expression of the slow (SA node) and cardiac (surrounding tissue) forms of troponin I. Nerve cells in the sections were identified by detection of GAP-43 and cytoskeletal middle neurofilament. Transcript expression was characterized for the 4 hyperpolarization-activated cation channels, 6 voltage-gated Na(+) channels, 3 voltage-gated Ca(2+) channels, 24 voltage-gated K(+) channel α-subunits, and 3 ancillary subunits. To ensure that transcript expression was representative of protein expression, immunofluorescence was used to verify localization patterns of voltage-dependent K(+) channels. Colocalizations were performed to observe any preferential patterns. Some overlapping and nonoverlapping binding patterns were observed. Measurement of different cation channel transcripts showed heterogeneous expression with many different patterns of expression, attesting to the complexity of electrical activity in the SA node. This study provides insight into the possible role ion channel heterogeneity plays in SA node pacemaker activity.

Atrial Fibrillation

DEFF Research Database (Denmark)

Staerk, Laila; Sherer, Jason A; Ko, Darae

2017-01-01

The past 3 decades have been characterized by an exponential growth in knowledge and advances in the clinical treatment of atrial fibrillation (AF). It is now known that AF genesis requires a vulnerable atrial substrate and that the formation and composition of this substrate may vary depending...... on comorbid conditions, genetics, sex, and other factors. Population-based studies have identified numerous factors that modify the atrial substrate and increase AF susceptibility. To date, genetic studies have reported 17 independent signals for AF at 14 genomic regions. Studies have established...

The role of atrial fibrillation on mortality and morbidity in patients with ischaemic stroke

International Nuclear Information System (INIS)

Cogen, E.E.; Tombul, T.; Yildirim, G.; Odabas, F.O.; Sayin, R.

2013-01-01

Objective: To investigate the impact of atrial fibrillation on mortality and morbidity in ischaemic stroke patients. Methods: The retrospective study was conducted at the Neurology Clinic, Faculty of Medicine, Yuzuncu Yil University, Van, Turkey, and comprised records of ischaemic stroke patients hospitalised between January 2006 and September 2009. SPSS 13 was used for statistical analysis. Results: Of the 404 patients in the study, 69 (17.1%) had atrial fibrilation. The mean age of such patients was 66.78+9-12.23 years compared to 61.01+-15.11 years for the rest. Besides 47 (68.1%) of these patients were females. According to the modified Rankin Scale scores, the degree of disability was significantly higher at the time of arrival and discharge, and mortality rates were significantly higher also (p<0.01). Conclusion: Atrial fibrillation affected the prognosis of ischaemic stroke adversely in terms of mortality and morbidity. (author)

The role of atrial fibrillation on mortality and morbidity in patients with ischaemic stroke

International Nuclear Information System (INIS)

Cogen, E.E.; Tmbul, T.; Yildirim, G.; Sayin, R.

2013-01-01

To investigate the impact of atrial fibrillation on mortality and morbidity in ischaemic stroke patients. Methods: The retrospective study was conducted at the Neurology Clinic, Faculty of Medicine, Yuzuncu Yil University, Van, Turkey, and comprised records of ischaemic stroke patients hospitalised between January 2006 and September 2009. SPSS 13 was used for statistical analysis. Results: Of the 404 patients in the study, 69 (17.1%) had atrial fibrilation. The mean age of such patients was 66.78+-12.23 years compared to 61.01+-15.11 years for the rest. Besides 47 (68.1%) of these patients were females. According to the modified Rankin Scale scores, the degree of disability was significantly higher at the time of arrival and discharge, and mortality rates were significantly higher also (p<0.01). Conclusion: Atrial fibrillation affected the prognosis of ischaemic stroke adversely in terms of mortality and morbidity. (author)

Análise comparativa entre a vascularização arterial ventricular e do nó sinoatrial em corações de cães Comparative analysis between both ventricular and sinoatrial node arterial vascularization in heart of dogs

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Caio Biasi

2013-01-01

vascularization the left coronary artery was predominant and gave rise to the paraconal interventricular and subsinuous branches. The region occupied by the sinoatrial node was most frequently (17 times, 42.5% in dependence of the left atrial proximal branch or in the collateral branch of that vessel, coming from the left circumflex branch, or this vessel was associated with the right atrial distal branch (8 times, 20%. With less frequency (14 times, 30%, in the area occupied by the sinoatrial node we found only the collaterals of the right circumflex branch, only the right atrial distal branch (10 times, 25%, only the right atrial proximal branch (3 times, 7.5% or exclusively the right atrial intermediary branch (once, 2.5%. In just one case (once, 2.5% in the area of the sinoatrial node we observed only the collateral of the left circumflex branch, i.e. the left atrial distal branch. According to our results we concluded that in this specie there is no relationship between the type of ventricular vascularization and irrigation of the sinoatrial node. In doing so, to consider just the ventricular branches is not sufficient for a clinical and surgical applied understanding, since the atrial branches make an important contribution to the sinoatrial node vascularization.

Nebivolol in preventing atrial fibrillation following coronary surgery in patients over 60 years of age

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Nevzat Erdil

2014-12-01

Full Text Available Objective: Postoperative atrial fibrillation is a common complication after cardiac surgery, with an incidence as high as 20-50%. Increased age is associated with a significant increase in postoperative atrial fibrillation risk. This common complication is associated with higher morbidity and mortality rates. The aim of this study was to assess the efficacy of nebivolol in preventing atrial fibrillation following coronary artery bypass surgery in patients over 60 years of age. Methods: In this prospective randomized study, 200 patients who were candidates for elective coronary artery bypass surgery were divided into two groups. The first group was administered with nebivolol and the second group was administered with metoprolol. Treatment was initiated four days prior to surgery, and patients were monitored for atrial fibrillation until discharge. Forty-one patients recieved 50 mg metoprolol succinate daily, which was initiated minimum 4 days before surgery. Results: Demographic data were similar in both groups. The incidence of postoperative atrial fibrillation in both groups was similar, with no significant difference being identified [n=20 (20%; n=18 (18%, P=0.718; respectively]. There were not any mortality at both groups during study. Inotropic agent requirement at ICU was similar for both groups [n=12 (12%, n=18 (18%, P=0.32]. Conclusion: We compared the effectiveness of nebivolol and metoprolol in decreasing the incidence of postoperative atrial fibrillation, and determined that nebivolol was as effective as metoprolol in preventing postoperative atrial fibrillation at patients. Nebivolol may be the drug of choice due to its effects, especially after elective coronary artery bypass surgery.

Atorvastatin can ameliorate left atrial stunning induced by radiofrequency ablation for atrial fibrillation.

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Xie, Ruiqin; Yang, Yingtao; Cui, Wei; Yin, Hongning; Zheng, Hongmei; Zhang, Jidong; You, Ling

2017-09-01

The objective of this study was to study the functional changes of the left atrium after radiofrequency ablation treatment for atrial fibrillation and the therapeutic effect of atorvastatin. Fifty-eight patients undergoing radiofrequency ablation for atrial fibrillation were randomly divided into non-atorvastatin group and atorvastatin group. Patients in the atorvastatin group were treated with atorvastatin 20 mg p.o. per night in addition to the conventional treatment of atrial fibrillation; patients in the non-atorvastatin group received conventional treatment of atrial fibrillation only. Echocardiography was performed before radiofrequency ablation operation and 1 week, 2 weeks, 3 weeks, and 4 weeks after operation. Two-dimensional ultrasound speckle tracking imaging system was used to measure the structural indexes of the left atrium. Results indicated that there was no significant change for indexes representing the structural status of the left atrium within a month after radiofrequency ablation (P > 0.05); however, there were significant changes for indexes representing the functional status of the left atrium. There were also significant changes in indexes reflecting left atrial strain status: the S and SRs of atorvastatin group were higher than those of non-atorvastatin group (P atorvastatin could improve left atrial function and shorten the duration of atrial stunning after radiofrequency ablation of atrial fibrillation.

Atrial Heterogeneity Generates Re-entrant Substrate during Atrial Fibrillation and Anti-arrhythmic Drug Action: Mechanistic Insights from Canine Atrial Models

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Varela, Marta; Hancox, Jules C.; Aslanidi, Oleg V.

2016-01-01

Anti-arrhythmic drug therapy is a frontline treatment for atrial fibrillation (AF), but its success rates are highly variable. This is due to incomplete understanding of the mechanisms of action of specific drugs on the atrial substrate at different stages of AF progression. We aimed to elucidate the role of cellular, tissue and organ level atrial heterogeneities in the generation of a re-entrant substrate during AF progression, and their modulation by the acute action of selected anti-arrhythmic drugs. To explore the complex cell-to-organ mechanisms, a detailed biophysical models of the entire 3D canine atria was developed. The model incorporated atrial geometry and fibre orientation from high-resolution micro-computed tomography, region-specific atrial cell electrophysiology and the effects of progressive AF-induced remodelling. The actions of multi-channel class III anti-arrhythmic agents vernakalant and amiodarone were introduced in the model by inhibiting appropriate ionic channel currents according to experimentally reported concentration-response relationships. AF was initiated by applied ectopic pacing in the pulmonary veins, which led to the generation of localized sustained re-entrant waves (rotors), followed by progressive wave breakdown and rotor multiplication in both atria. The simulated AF scenarios were in agreement with observations in canine models and patients. The 3D atrial simulations revealed that a re-entrant substrate was typically provided by tissue regions of high heterogeneity of action potential duration (APD). Amiodarone increased atrial APD and reduced APD heterogeneity and was more effective in terminating AF than vernakalant, which increased both APD and APD dispersion. In summary, the initiation and sustenance of rotors in AF is linked to atrial APD heterogeneity and APD reduction due to progressive remodelling. Our results suggest that anti-arrhythmic strategies that increase atrial APD without increasing its dispersion are

Prospects of Sino-India Relations 2020

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2011-06-01

Nature of Sino-India Bilateral Trade256 Some economists point to China‘s dumping practices and currency devaluation as sources of this disequilibrium...Missile IMF - International Monetary Fund IOR - Indian Ocean Region IR - International Relations IRBM - Intermediate Range Ballistic Missile IT...there!‖227 In the period 2004 to 2006, China outbid India at various auctions including those in Angola, Nigeria , Ecuador, and Kazakhstan. China‘s

Thromboembolic risk in 16 274 atrial fibrillation patients undergoing direct current cardioversion with and without oral anticoagulant therapy

DEFF Research Database (Denmark)

Hansen, Morten Lock; Jepsen, Rikke Malene H G; Olesen, Jonas Bjerring

2015-01-01

-time DC cardioversion for atrial fibrillation between 2000 and 2008. Use of oral anticoagulant therapy within 90 days prior and 360 days after DC cardioversion was obtained from the Danish Register of Medicinal Product Statistics. The risk of thromboembolism was estimated by calculating incidence rates......AIMS: To study the risk of thromboembolism in a nationwide cohort of atrial fibrillation patients undergoing direct current (DC) cardioversion with or without oral anticoagulant coverage. METHODS AND RESULTS: A retrospective study of 16 274 patients in Denmark discharged from hospital after a first...... and by multivariable adjusted Cox proportional-hazard models. During the initial 30 days following discharge, the thromboembolic incidence rate was 10.33 per 100 patient-years for the no prior oral anticoagulant therapy group [n = 5084 (31.2%)], as compared with 4.00 per 100 patient-years for the prior oral...

Atrial fibrillation and hyperthyroidism: A literature review.

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Reddy, Vivek; Taha, Wael; Kundumadam, Shanker; Khan, Mazhar

Atrial fibrillation is the most common arrhythmia worldwide with increasing frequency noted with age. Hyperthyroidism is a well-known cause of atrial fibrillation with a 16%-60% prevalence of atrial fibrillation in patients with known hyperthyroidism Ross et al. (2016). While hyperthyroidism as a causative factor of atrial fibrillation is well established, this literature review aims to answer several questions on this topic including: 1. The relationship of atrial fibrillation to hyperthyroidism 2. Atrial fibrillation as a predictor of hyperthyroidism 3. The pathophysiology of thyrotoxic atrial fibrillation 4. Subclinical hyperthyroidism and the relationship with atrial fibrillation 5. Cardioversion and Catheter ablation of hyperthyroid patients with atrial fibrillation 6. Thrombotic risk of hyperthyroid patients with atrial fibrillation 7. Management of Thyrotoxic Atrial fibrillation 8. Pharmacological rhythm control in patients with hyperthyroidism and atrial fibrillation 9. Treatment of Hyperthyroidism to prevent atrial fibrillation 10. Clinical Implications of Hyperthyroidism and Atrial Fibrillation. Copyright © 2017 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Pharmacological Treatment for Atrial Fibrillation

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Kaoru Sugi, MD PhD

2005-01-01

Full Text Available Pharmacological treatment for atrial fibrillation has a variety of purposes, such as pharmacological defibrillation, maintenance of sinus rhythm, heart rate control to prevent congestive heart failure and prevention of both cerebral infarction and atrial remodeling. Sodium channel blockers are superior to potassium channel blockers for atrial defibrillation, while both sodium and potassium channel blockers are effective in the maintenance of sinus rhythm. In general, digitalis or Ca antagonists are used to control heart rate during atrial fibrillation to prevent congestive heart failure, while amiodarone or bepridil also reduce heart rates during atrial fibrillation. Anticoagulant therapy with warfarin is recommended to prevent cerebral infarction and angiotensin converting enzyme antagonists or angiotensin II receptor blockers are also used to prevent atrial remodeling. One should select appropriate drugs for treatment of atrial fibrillation according to the patient's condition.

The incidence and characteristics of supraventricular tachycardia in left atrial isomerism: a high incidence of atrial fibrillation in young patients.

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Miyazaki, Aya; Sakaguchi, Heima; Ohuchi, Hideo; Yamamoto, Tetsuya; Igarashi, Takehiro; Negishi, Jun; Toyota, Naoki; Kagisaki, Koji; Yagihara, Toshikatsu; Yamada, Osamu

2013-06-20

In left atrial isomerism (LAI), both atria show left atrial morphology. Although bradyarrhythmias are frequent and highly complex in LAI patients, previous studies have reported a low incidence of supraventricular tachycardia (SVT). To evaluate the incidence and characteristics of SVT in LAI, we retrospectively evaluated the clinical characteristics of SVTs in 83 patients with LAI (age at last follow-up, 15.3±10.5 years). There were 27 SVTs in 19 patients (23%), including nine episodes of atrial fibrillation (AF) and eight non-reentrant SVTs. Sixteen of the 19 patients with SVT had histories of atriotomy, but the three patients with AF or non-reentrant tachycardia had no history of atriotomy. The rates of freedom from SVT were 66% and 59% at ages of 20 and 30 years, respectively; the corresponding rates for freedom from AF were 89% and 74%. In multivariate analysis, the predictors of SVT were age (OR, 1.14; 95% CI, 1.06-1.26; p=0.003) and sinus node dysfunction (SND) (OR, 3.88; 95% CI, 1.57-13.34; p=0.01). In patients with LAI, SVTs are common, and AF and non-reentrant SVTs are the major type of SVTs. The incidence of AF was high in young patients with LAI. The lack of anatomical barriers in the atria that allow the formation of macro-reentrant circuits may account for the higher incidence of AF and non-reentrant SVT than macro-reentrant tachycardia. Moreover, the increasing prevalence of SND with age should contribute to a higher incidence of SVT. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Acidosis slows electrical conduction through the atrio-ventricular node.

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Nisbet, Ashley M; Burton, Francis L; Walker, Nicola L; Craig, Margaret A; Cheng, Hongwei; Hancox, Jules C; Orchard, Clive H; Smith, Godfrey L

2014-01-01

Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN). In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode's solution (20% CO2, pH 6.7) increased the time of earliest activation (Tact) from 100.5 ± 7.9 to 166.1 ± 7.2 ms (n = 8) at a pacing cycle length (PCL) of 300 ms (37°C). Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150 ms PCL, Tact was prolonged from 131.0 ± 5.2 to 174.9 ± 16.3 ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode's solutions at pH 7.4 (control), 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH) interval, the AVN effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis.

Acidosis slows electrical conduction through the atrio-ventricular node

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Ashley Muir Nisbet

2014-06-01

Full Text Available Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN. In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode’s solution (20% CO2, pH 6.7 increased the time of earliest activation (Tact from 100.5+7.9 to 166.1+7.2ms (n=8 at a pacing cycle length (PCL of 300ms (37oC. Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150ms PCL, Tact was prolonged from 131.0+5.2 to 174.9+16.3ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode’s solutions at pH 7.4 (control, 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH interval, the effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis.

Atrial remodeling and metabolic dysfunction in idiopathic isolated fibrotic atrial cardiomyopathy.

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Cui, Chang; Jiang, Xiaohong; Ju, Weizhu; Wang, Jiaxian; Wang, Daowu; Sun, Zheng; Chen, Minglong

2018-04-26

Idiopathic isolated fibrotic atrial cardiomyopathy (IIF-ACM) is a novel subtype of cardiomyopathy characterized by atrial fibrosis that does not involve the ventricular myocardium and is associated with significant atrial tachyarrhythmia. The mechanisms underlying its pathogenesis are unknown. Atrium samples were obtained from 3 patients with IIF-ACM via surgical intervention. Control samples were consisted of 3 atrium biopsies from patients with congenital heart disease and normal sinus rhythm, matched for gender, age and basic clinical characteristics. Comparative histology, immunofluorescence staining, electron microscopy and proteomics analyses were carried out to explore the unique pathogenesis of IIF-ACM. IIF-ACM atria displayed disordered myofibrils, profound fibrosis and mitochondrial damages compared to the control atria. Proteomics profiling identified metabolic pathways as the most profound changes in IIF-ACM. Our study suggested that metabolic changes in the atrial myocardium caused mitochondrial oxidative stress and potential cell damage, which further led to atrial fibrosis and myofibril disorganization, the characteristic phenotype of IIF-ACM. Copyright © 2017 Elsevier B.V. All rights reserved.

Atrial fibrillation and delayed gastric emptying.

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Isadora C Botwinick

Full Text Available BACKGROUND: Atrial fibrillation and delayed gastric emptying (DGE are common after pancreaticoduodenectomy. Our aim was to investigate a potential relationship between atrial fibrillation and DGE, which we defined as failure to tolerate a regular diet by the 7(th postoperative day. METHODS: We performed a retrospective chart review of 249 patients who underwent pancreaticoduodenectomy at our institution between 2000 and 2009. Data was analyzed with Fisher exact test for categorical variables and Mann-Whitney U or unpaired T-test for continuous variables. RESULTS: Approximately 5% of the 249 patients included in the analysis experienced at least one episode of postoperative atrial fibrillation. Median age of patients with atrial fibrillation was 74 years, compared with 66 years in patients without atrial fibrillation (p = 0.0005. Patients with atrial fibrillation were more likely to have a history of atrial fibrillation (p = 0.03. 92% of the patients with atrial fibrillation suffered from DGE, compared to 46% of patients without atrial fibrillation (p = 0.0007. This association held true when controlling for age. CONCLUSION: Patients with postoperative atrial fibrillation are more likely to experience delayed gastric emptying. Interventions to manage delayed gastric function might be prudent in patients at high risk for postoperative atrial fibrillation.

Antiplatelet therapy is not a safer alternative to oral anticoagulants, even in older hospital-discharged patients with atrial fibrillation

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Mario Bo

2016-10-01

Full Text Available Although oral anticoagulant therapy (OAT is recommended for patients with atrial fibrillation (AF, it is widely underused among older patients, who are frequently prescribed antiplatelet therapy (APT instead. We assessed mortality and incidence of ischemic and hemorrhagic events according to prescription of OAT or APT in older medical in-patients with AF discharged from hospital. Stroke and bleeding risk were evaluated using the CHA2DS2-VASC (Congestive heart failure/ left ventricular dysfunction, Hypertension, Aged ≥75 years, Diabetes Mellitus, Stroke/transient ischemic attack/systemic embolism, Vascular Disease, Aged 65-74 years, Sex Category and HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly, Drugs/alcohol concomitantly scores. Comorbidity, cognitive status and functional autonomy were assessed using standardized scales. Association of OAT and APT with overall mortality, ischemic stroke and bleeding events was evaluated through multivariate analysis and propensity score matching. During a mean follow-up period of 11 months 384 of the 962 patients discharged (mean age 82.9±6.6 years, 59.1% female died (39.9%, 66 had an ischemic stroke and 49 experienced a major bleeding event. Compared with APT, OAT was associated with reduced overall mortality after multivariate analysis [odds ratio (OR 0.62, confidence interval (CI: 0.46-0.83] and after propensity score matched analysis (OR 0.65, CI: 0.52-0.82, P=0.0004, with a not significant reduced incidence of total and fatal ischemic stroke, and without increase in total, intracranial, major and fatal bleedings. In a sample of older AF patients with poor health status, OAT was associated with reduced mortality, without evidence of a significant increase in major or fatal bleedings.

Left Atrial Size and Function in a Canine Model of Chronic Atrial Fibrillation and Heart Failure

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Goldberg, Adam; Kusunose, Kenya; Qamruddin, Salima; Rodriguez, L. Leonardo; Mazgalev, Todor N.; Griffin, Brian P.; Van Wagoner, David R.; Zhang, Youhua; Popović, Zoran B.

2016-01-01

Background Our aim was to assess how atrial fibrillation (AF) induction, chronicity, and RR interval irregularity affect left atrial (LA) function and size in the setting of underlying heart failure (HF), and to determine whether AF effects can be mitigated by vagal nerve stimulation (VNS). Methods HF was induced by 4-weeks of rapid ventricular pacing in 24 dogs. Subsequently, AF was induced and maintained by atrial pacing at 600 bpm. Dogs were randomized into control (n = 9) and VNS (n = 15) groups. In the VNS group, atrioventricular node fat pad stimulation (310 μs, 20 Hz, 3–7 mA) was delivered continuously for 6 months. LA volume and LA strain data were calculated from bi-weekly echocardiograms. Results RR intervals decreased with HF in both groups (p = 0.001), and decreased further during AF in control group (p = 0.014), with a non-significant increase in the VNS group during AF. LA size increased with HF (p<0.0001), with no additional increase during AF. LA strain decreased with HF (p = 0.025) and further decreased after induction of AF (p = 0.0001). LA strain decreased less (p = 0.001) in the VNS than in the control group. Beat-by-beat analysis showed a curvilinear increase of LA strain with longer preceding RR interval, (r = 0.45, p <0.0001) with LA strain 1.1% higher (p = 0.02) in the VNS-treated animals, independent of preceding RR interval duration. The curvilinear relationship between ratio of preceding and pre-preceding RR intervals, and subsequent LA strain was weaker, (r = 0.28, p = 0.001). However, VNS-treated animals again had higher LA strain (by 2.2%, p = 0.002) independently of the ratio of preceding and pre-preceding RR intervals. Conclusions In the underlying presence of pacing-induced HF, AF decreased LA strain, with little impact on LA size. LA strain depends on the preceding RR interval duration. PMID:26771573

[No Hodgkin Linfoma diagnosis with intra-atrial infiltration].

Science.gov (United States)

Alcocer Gamba, Marco Antonio; León González, Salvador; Castro Montes, Eliodoro; Loarca Piña, Luis Martín; Lugo Gavidia, Leslie Marisol; García Hernández, Enrique; González Galindo, Ulises; Paredes Serrano, Miguel Isaías

2012-09-01

Cardiac tumors are rare entities in clinical practice, with an incidence of 0.05%. Approximately 75% are benign and 25% malignant. Among these, Lymphomas are uncommon, representing about 0.25%. The non-Hodgkin lymphomas can occur in extranodal tissues in 20% of the cases and 80% of these non-Hodgkin lymphomas are composed of diffuse B cells. The extranodal presentation is most frequent in young adults, with a high degree of malignancy and rapid growth. It can present with primary infiltration of various organs; cardiac involvement occurs in 20 to 28% of cases, usually located in the right chambers and with nonspecific symptoms, depending on the location and extent of the tumor. The diagnostic test in these cases is undoubtedly the biopsy of the lymph node or the affected tissue. We present the case of non-Hodgkin disease of diffuse large cells, with right intra-atrial involvement in a 23-year-old-female patient, who presented with progressive dyspnea. A transesophageal echocardiography was performed and an intra-atrial tumor mass was detected. A biopsy was performed, by femoral venous catheterization, allowing the establishment of the histopathological diagnosis and treatment. At a one year follow up, the patient shows complete remission.

3D virtual human atria: A computational platform for studying clinical atrial fibrillation.

Science.gov (United States)

Aslanidi, Oleg V; Colman, Michael A; Stott, Jonathan; Dobrzynski, Halina; Boyett, Mark R; Holden, Arun V; Zhang, Henggui

2011-10-01

Despite a vast amount of experimental and clinical data on the underlying ionic, cellular and tissue substrates, the mechanisms of common atrial arrhythmias (such as atrial fibrillation, AF) arising from the functional interactions at the whole atria level remain unclear. Computational modelling provides a quantitative framework for integrating such multi-scale data and understanding the arrhythmogenic behaviour that emerges from the collective spatio-temporal dynamics in all parts of the heart. In this study, we have developed a multi-scale hierarchy of biophysically detailed computational models for the human atria--the 3D virtual human atria. Primarily, diffusion tensor MRI reconstruction of the tissue geometry and fibre orientation in the human sinoatrial node (SAN) and surrounding atrial muscle was integrated into the 3D model of the whole atria dissected from the Visible Human dataset. The anatomical models were combined with the heterogeneous atrial action potential (AP) models, and used to simulate the AP conduction in the human atria under various conditions: SAN pacemaking and atrial activation in the normal rhythm, break-down of regular AP wave-fronts during rapid atrial pacing, and the genesis of multiple re-entrant wavelets characteristic of AF. Contributions of different properties of the tissue to mechanisms of the normal rhythm and arrhythmogenesis were investigated. Primarily, the simulations showed that tissue heterogeneity caused the break-down of the normal AP wave-fronts at rapid pacing rates, which initiated a pair of re-entrant spiral waves; and tissue anisotropy resulted in a further break-down of the spiral waves into multiple meandering wavelets characteristic of AF. The 3D virtual atria model itself was incorporated into the torso model to simulate the body surface ECG patterns in the normal and arrhythmic conditions. Therefore, a state-of-the-art computational platform has been developed, which can be used for studying multi

Atrial Fibrillation and Hyperthyroidism

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Jayaprasad N

2005-10-01

Full Text Available Atrial fibrillation occurs in 10 – 15% of patients with hyperthyroidism. Low serum thyrotropin concentration is an independent risk factor for atrial fibrillation. Thyroid hormone contributes to arrythmogenic activity by altering the electrophysiological characteristics of atrial myocytes by shortening the action potential duration, enhancing automaticity and triggered activity in the pulmonary vein cardio myocytes. Hyperthyroidism results in excess mortality from increased incidence of circulatory diseases and dysrhythmias. Incidence of cerebral embolism is more in hyperthyroid patients with atrial fibrillation, especially in the elderly and anti-coagulation is indicated in them. Treatment of hyperthyroidism results in conversion to sinus rhythm in up to two-third of patients. Beta-blockers reduce left ventricular hypertrophy and atrial and ventricular arrhythmias in patients with hyperthyroidism. Treatment of sub clinical hyperthyroidism is controversial. Optimizing dose of thyroxine treatment in those with replacement therapy and beta-blockers is useful in exogenous subclinical hyperthyroidism.

Abnormal atrial activation in young patients with lone atrial fibrillation

DEFF Research Database (Denmark)

Holmqvist, Fredrik; Olesen, Morten S; Tveit, Arnljot

2011-01-01

Patients with a history of atrial fibrillation (AF) have previously been shown to have altered atrial conduction, as seen non-invasively using signal-averaged P-wave analysis. However, little is known about the P-wave morphology in patients in the early phases of AF with structurally normal hearts....

Risk Factors for Atrial Fibrillation

NARCIS (Netherlands)

B.P. Krijthe (Bouwe)

2013-01-01

textabstractAtrial fibrillation is a common cardiac arrhythmia that is characterized by rapid disorganized atrial electrical activity resulting in absence of atrial contractions. It is diagnosed on the basis of typical findings on an electrocardiogram (ECG). The characteristic ECG findings are

Result of radiation therapy of sino-nasal cancers using partial attenuation filter

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Kim, Jin Hee; Kim, Ok Bae; Choi, Tae Jin [Keimyung University College of Medicine, Daegu (Korea, Republic of)

2007-06-15

This study was to evaluate the survival and pattern of failure after radiation therapy of sino-nasal cancer using partial attenuation filer and wedged beams and to help radiotherapy planning of sino-nasal cancer. Between February 1992 and March 2003, 17 patients with sino-nasal cancers underwent radiation therapy using partial attenuation filter at Dongsan Medical Center, Keimyung university. There were 9 male and 8 female patients. Patients' age ranged from 40 to 75 years (median 59 years). There were 10 patients of maxillary sinus cancer, 7 patients of nasal cancer. The histologic type was squamous cell carcinoma in 11, adenoid cystic carcinoma in 4 and olfactory neuroblastoma in 2. The distribution of clinical stage by the AJCC system was 3 for stage II, 7 for III and 6 for IV. The five patients were treated with radiation alone and 12 patients were treated with surgery and postoperative radiation therapy. The range of total radiation dose delivered to the primary tumor was from 44 to 76 Gy (median 60 Gy). The follow-up period ranged from 3 to 173 months with median of 78 months. The overall 2 year survival rate and disease free survival rate was 76.4%. The 5 year and 10 year survival rate were 76.4% and 45.6% and the 5 year and 10 year disease free survival rate was 70.6%. The 5 year disease free survival rate by treatment modality was 91.6% for postoperative radiation group and 20% for radiation alone group, statistical significance was found by treatment modality ({rho} = 0.006). There were no differences in survival by pathology and stage. There were local failure in 5 patients (29%) but no distant failure and no severe complication required surgical intervention. Radiation therapy of sino-nasal cancer using partial attenuation filter was safe and effective. Combined modality with conservative surgery and radiation therapy was more advisable to achieve loco-regional control in sino-nasal cancer. Also we considered high precision radiation therapy with

Prednisone prevents atrial fibrillation promotion by atrial tachycardia remodeling in dogs

NARCIS (Netherlands)

Shiroshita-Takeshita, A; Brundel, BJJM; Lavoie, J; Nattel, S

2006-01-01

Background: There is evidence suggesting involvement of oxidative stress, inflammation, and calcineurin/nuclear factor of activated T cell pathways in atrial fibrillation. This study evaluated the efficacy of anti-inflammatory and calcineurin-inhibitory drugs on promotion of atrial fibrillation by

[Morphological and electrophysiological changes of the heart atria in necropsy patients with atrial fibrillation - a pilot study].

Science.gov (United States)

Matějková, Adéla; Steiner, Ivo

2014-01-01

Atrial fibrillation (AF), the most common supraventricular tachycardia, has a morphological base, so called remodelation of atrial myocardium, with its abnormal conduction pattern as a consequence. The remodelation regards electrical, contractile, and structural properties. In this pilot study we attempted to find relations between the myocardial morphological (scarring, amyloidosis, left atrial enlargement) and electrophysiological (ECG characteristics of the P-wave) changes in patients with AF. We examined 40 hearts of necropsy patients - 20 with a history of AF and 20 with no history of AF. Grossly, the heart weight and the size of the left atrium (LA) were evaluated. Histologically, 7 standard sites from the atria were examined. In each specimen, the degree of myocardial scarring and of deposition of isolated atrial amyloid (IAA) were assessed. We failed to show any significant difference in the P-wave pattern between patients with and without AF. Morphologically, however, there were several differences - the patients with AF had significantly heavier hearts, larger left atria, more severely scarred myocardium of the LA and the atrial septum, and more severe deposition of IAA in both atria in comparison to the control group of patients with sinus rhythm. The left atrial distribution of both fibrosis and amyloidosis was irregular. In patients with AF the former was most pronounced in the LA ceiling while the latter in the LA anterior wall. The entire series showed more marked amyloidosis in the left than in the right atrium. An interesting finding was the universal absence of IAA in the sinoatrial node. The knowledge of distribution of atrial myocardial structural changes could be utilized by pathologists in taking specimens for histology and also by cardiologists in targeting the radiofrequency ablation therapy.

Atrial antitachycardia pacing and atrial remodeling: A substudy of the international, randomized MINERVA trial.

Science.gov (United States)

Boriani, Giuseppe; Tukkie, Raymond; Biffi, Mauro; Mont, Lluis; Ricci, Renato; Pürerfellner, Helmut; Botto, Giovanni Luca; Manolis, Antonis S; Landolina, Maurizio; Gulizia, Michele; Hudnall, J Harrison; Mangoni, Lorenza; Grammatico, Andrea; Padeletti, Luigi

2017-10-01

Atrial tachycardia (AT) and atrial fibrillation (AF) are common in pacemaker patients and are associated with bad prognoses. The purpose of this study was to evaluate atrial antitachycardia pacing impact on AT/AF-induced atrial remodeling, measured by early recurrence of AT/AF (ERAF) and by change in left atrial diameter (LAD), and to evaluate the impact of AT/AF duration on ERAF incidence. Pacemaker patients were randomized to dual-chamber pacing (Control DDDR: 385 patients), managed ventricular pacing (MVP: 398 patients), or atrial antitachycardia pacing plus MVP (DDDRP+MVP: 383 patients). LAD change, estimated by echocardiography, was considered significant if the relative difference between baseline and 24-month measurements was >10%. At median follow-up of 34 months, ERAF incidence was significantly lower in the DDDRP+MVP arm for all AT/AF durations, in particular, ERAF followed AT/AF longer than 3 hours in 53% cases in Control DDDR, in 51% cases in MVP, and in 39% cases in DDDRP+MVP (P MVP, and 70% in DDDRP+MVP (P MVP, DDDRP+MVP reduces ERAF and favors LAD reduction, suggesting that atrial antitachycardia pacing may reverse electrical and mechanical remodeling. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Environment and society: the Sinos River Basin and public policies

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V Pedde

Full Text Available This study discusses the tensions and conflicts in the relationship between environment and society in the Sinos River Basin, in the state of Rio Grande do Sul, Brazil. An environmental disaster in 2006, which resulted in the death of 100 tons of fish in the Sinos River, is the dividing line for this study. A review of documents and field interviews with representatives of the municipal government and companies in the region were used to analyze the impact of public policies on the environment and which deficiencies remain11We thank Malcon Naor Voltz and Ana Arnoldo, undergraduate research grant holders, for their participation in data collection for this study..

Applying non-linear dynamics to atrial appendage flow data to understand and characterize atrial arrhythmia

International Nuclear Information System (INIS)

Chandra, S.; Grimm, R.A.; Katz, R.; Thomas, J.D.

1996-01-01

The aim of this study was to better understand and characterize left atrial appendage flow in atrial fibrillation. Atrial fibrillation and flutter are the most common cardiac arrhythmias affecting 15% of the older population. The pulsed Doppler velocity profile data was recorded from the left atrial appendage of patients using transesophageal echocardiography. The data was analyzed using Fourier analysis and nonlinear dynamical tools. Fourier analysis showed that appendage mechanical frequency (f f ) for patients in sinus rhythm was always lower (around1 Hz) than that in atrial fibrillation (5-8 Hz). Among patients with atrial fibrillation spectral power below f f was significantly different suggesting variability within this group of patients. Results that suggested the presence of nonlinear dynamics were: a) the existence of two arbitrary peak frequencies f 1 , f 2 , and other peak frequencies as linear combinations thereof (mf 1 ±nf 2 ), and b) the similarity between the spectrum of patient data and that obtained using the Lorenz equation. Nonlinear analysis tools, including Phase plots and differential radial plots, were also generated from the velocity data using a delay of 10. In the phase plots, some patients displayed a torus-like structure, while others had a more random-like pattern. In the differential radial plots, the first set of patients (with torus-like phase plots) showed fewer values crossing an arbitrary threshold of 10 than did the second set (8 vs. 27 in one typical example). The outcome of cardioversion was different for these two set of patients. Fourier analysis helped to: differentiate between sinus rhythm and atrial fibrillation, understand the characteristics of the wide range of atrial fibrillation patients, and provide hints that atrial fibrillation could be a nonlinear process. Nonlinear dynamical tools helped to further characterize and sub-classify atrial fibrillation

Role of atrial endothelial cells in the development of atrial fibrosis and fibrillation in response to pressure overload.

Science.gov (United States)

Kume, Osamu; Teshima, Yasushi; Abe, Ichitaro; Ikebe, Yuki; Oniki, Takahiro; Kondo, Hidekazu; Saito, Shotaro; Fukui, Akira; Yufu, Kunio; Miura, Masahiro; Shimada, Tatsuo; Takahashi, Naohiko

Monocyte chemoattractant protein-1 (MCP-1)-mediated inflammatory mechanisms have been shown to play a crucial role in atrial fibrosis induced by pressure overload. In the present study, we investigated whether left atrial endothelial cells would quickly respond structurally and functionally to pressure overload to trigger atrial fibrosis and fibrillation. Six-week-old male Sprague-Dawley rats underwent suprarenal abdominal aortic constriction (AAC) or a sham operation. By day 3 after surgery, macrophages were observed to infiltrate into the endocardium. The expression of MCP-1 and E-selectin in atrial endothelium and the expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and ED1 in left atrial tissue were enhanced. Atrial endothelial cells were irregularly hypertrophied with the disarrangement of lines of cells by scanning electron microscopy. Various-sized gap formations appeared along the border in atrial endothelial cells, and several macrophages were located just in the endothelial gap. Along with the development of heterogeneous interstitial fibrosis, interatrial conduction time was prolonged and the inducibility of atrial fibrillation by programmed extrastimuli was increased in the AAC rats compared to the sham-operated rats. Atrial endothelium responds rapidly to pressure overload by expressing adhesion molecules and MCP-1, which induce macrophage infiltration into the atrial tissues. These processes could be an initial step in the development of atrial remodeling for atrial fibrillation. Copyright © 2016 Elsevier Inc. All rights reserved.

[Echocardiographic diagnosis of atrial thrombosis].

Science.gov (United States)

Pinto Tortolero, R; Vargas Barrón, J; Rodas, M A; Díaz de la Vega, V; Horwitz, S

1982-01-01

Seventy patients with rheumatic mitral disease were studied by M-Mode and 2D echocardiography in order to detect left atrial thrombosis before surgery. Thrombosis were suspected by the observation of abnormal echoes in the left atrium. During surgery 17 (24%) patients had atrial thrombosis. It had been suspected by echocardiography in 12 (sensitivity 70%). In 53 patients thrombosis were not found during surgery; in 46 the echo had been also negative (specificity 86%). There was a false positive detection of thrombosis by echo in 7 patients (14%) and false negativity in 5 (30%). Patients with atrial thrombosis had atrial fibrilation in 91% of cases; and the most frequent valvular disease was mitral stenosis. There was not a direct relationship among existence of left atrial thrombosis and the anteroposterior diameter of the left atrium as measured by echo. We conclude that echocardiography has good specificity to rule out atrial thrombosis and moderate sensitivity to detect it in rheumatic mitral disease.

Toxicity effects of nickel electroplating effluents treated by photoelectrooxidation in the industries of the Sinos River Basin.

Science.gov (United States)

Benvenuti, T; Rodrigues, Mas; Arenzon, A; Bernardes, A M; Zoppas-Ferreira, J

2015-05-01

The Sinos river Basin is an industrial region with many tanneries and electroplating plants in southern Brazil. The wastewater generated by electroplating contains high loads of salts and metals that have to be treated before discharge. After conventional treatment, this study applied an advanced oxidative process to degrade organic additives in the electroplating bright nickel baths effluent. Synthetic rinsing water was submitted to physical-chemical coagulation for nickel removal. The sample was submitted to ecotoxicity tests, and the effluent was treated by photoelectrooxidation (PEO). The effects of current density and treatment time were evaluated. The concentration of total organic carbon (TOC) was 38% lower. The toxicity tests of the effluent treated using PEO revealed that the organic additives were partially degraded and the concentration that is toxic for test organisms was reduced.

Toxicity effects of nickel electroplating effluents treated by photoelectrooxidation in the industries of the Sinos River Basin

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T Benvenuti

Full Text Available The Sinos river Basin is an industrial region with many tanneries and electroplating plants in southern Brazil. The wastewater generated by electroplating contains high loads of salts and metals that have to be treated before discharge. After conventional treatment, this study applied an advanced oxidative process to degrade organic additives in the electroplating bright nickel baths effluent. Synthetic rinsing water was submitted to physical-chemical coagulation for nickel removal. The sample was submitted to ecotoxicity tests, and the effluent was treated by photoelectrooxidation (PEO. The effects of current density and treatment time were evaluated. The concentration of total organic carbon (TOC was 38% lower. The toxicity tests of the effluent treated using PEO revealed that the organic additives were partially degraded and the concentration that is toxic for test organisms was reduced.

[Left atrial function and left atrial appendage flow velocity in hypertrophic cardiomyopathy: comparison of patients with and without paroxysmal atrial fibrillation].

Science.gov (United States)

Akasaka, K; Kawashima, E; Shiokoshi, T; Ishii, Y; Hasebe, N; Kikuchi, K

1998-07-01

The involvement of left atrial (LA) appendage flow velocity in reduced left atrial function was investigated in 24 patients with hypertrophic cardiomyopathy, who retained sinus rhythm at the examination. Patients were divided into 11 with a history of paroxysmal atrial fibrillation [PAf(+)] and 13 without such history [PAf(-)]. Transthoracic echocardiography was performed to evaluate LA fractional shortening (LA%FS) and mean velocity of circumferential LA fiber shortening (LAmVcf), as contractile functions of the left atrium at the phase of active atrial contraction. Transesophageal echocardiographic Doppler examination was performed in all patients to measure the LA appendage velocity. In all patients, significant positive correlations were observed between the LA appendage velocity and LA%FS (r = 0.50, p fibrillation were significantly lower than in those without (0.84 +/- 0.15 vs 1.28 +/- 0.37 circ/sec, 44 +/- 12 vs 65 +/- 20 cm/sec, both p fibrillation. These results indicate that there is a close relationship between LA appendage velocity and LA contractile function in patients with hypertrophic cardiomyopathy with paroxysmal atrial fibrilation, and these patients have potential risk of cerebral infarction.

Digoxin versus placebo, no intervention, or other medical interventions for atrial fibrillation and atrial flutter

DEFF Research Database (Denmark)

Sethi, Naqash; Safi, Sanam; Feinberg, Joshua

2017-01-01

BACKGROUND: Atrial fibrillation is the most common arrhythmia of the heart with a prevalence of approximately 2% in the western world. Atrial flutter, another arrhythmia, occurs less often with an incidence of approximately 200,000 new patients per year in the USA. Patients with atrial fibrillati...

Uterine perforation by a cystoperitoneal shunt, an unusual cause of recurrent vaginal discharge.

Science.gov (United States)

Poilblanc, Mathieu; Sentilhes, Loïc; Mercier, Philippe; Lefèbvre, Céline; Descamps, Philippe

2012-01-01

We describe the first reported case of uterine perforation by a cystoperitoneal shunt. The mechanism of this unusual complication is unclear. A 17-year-old patient had a cystoperitoneal shunt for a porencephalic cyst. She presented with recurrent watery vaginal discharge. A pelvic ultrasound examination showed that the uterus had been perforated by the distal tip of the shunt. The cystoperitoneal shunt was converted to a ventriculo-atrial shunt, and the vaginal discharge subsequently resolved. The appearance of light and clear vaginal discharge in a patient with a cystoperitoneal shunt raises the possibility of uterine perforation. This can be confirmed by ultrasound and analysis of the discharge. Removal of the shunt leads to spontaneous closure of the uterine defect.

Atrial fibrillation in the elderly

Science.gov (United States)

Franken, Roberto A.; Rosa, Ronaldo F.; Santos, Silvio CM

2012-01-01

This review discusses atrial fibrillation according to the guidelines of Brazilian Society of Cardiac Arrhythmias and the Brazilian Cardiogeriatrics Guidelines. We stress the thromboembolic burden of atrial fibrillation and discuss how to prevent it as well as the best way to conduct cases of atrial fibrillatios in the elderly, reverting the arrhythmia to sinus rhythm, or the option of heart rate control. The new methods to treat atrial fibrillation, such as radiofrequency ablation, new oral direct thrombin inhibitors and Xa factor inhibitors, as well as new antiarrhythmic drugs, are depicted. PMID:22916053

Atrial Na,K-ATPase increase and potassium dysregulation accentuate the risk of postoperative atrial fibrillation

DEFF Research Database (Denmark)

Tran, Cao Thach; Schmidt, Thomas Andersen; Christensen, John Brochorst

2009-01-01

BACKGROUND: Postoperative atrial fibrillation is a common complication to cardiac surgery. Na,K-ATPase is of major importance for the resting membrane potential and action potential. The purpose of the present study was to evaluate the importance of Na,K-ATPase concentrations in human atrial...... biopsies and plasma potassium concentrations for the development of atrial fibrillation. METHODS: Atrial myocardial biopsies were obtained from 67 patients undergoing open chest cardiac surgery. Na,K-ATPase was quantified using vanadate-facilitated 3H-ouabain binding. Plasma potassium concentration....../g wet weight (n = 33), p = 0.03]. Also with multivariable analysis, 3H-ouabain-binding site concentration was significantly associated with the development of atrial fibrillation. High increase in plasma potassium concentration during the perioperative period and surgery was associated...

[Effect of benazepril on atrial cytoskeleton remodeling in the canine atrial fibrillation models].

Science.gov (United States)

Liu, Li; Qu, Xiu-Fen; Yu, Yang; Bai, Bing; Huang, Yong-Lin

2009-10-20

To investigate the effect of benazepril on atrial cytoskeleton remodeling in atrial fibrillation (AF) canines induced by chronic rapid atrial pacing (RAP). Twenty canines were randomly divided into 3 groups: (1) Sham-operated group without RAP; (2) AF group: AF established by RAP at 600 beats per minute for 6 weeks; (3) Benazepril group: benazepril was dosed from 1 week pre-pacing to 6 weeks post-pacing. The diameter of atrial cardiomyocyte was measured, collagen volume fraction (CVF) analyzed by Masson staining and the expression and distribution of desmin were assayed by immunohistochemistry. RT-PCR method was used to semi-quantify the mRNA expression of beta-tubulin and desmin. The diameter of atrial cardiomyocyte increased in AF group [LA:(27.9 +/- 3.8) microm; RA: (26.8 +/- 3.2) microm] and benazepril group[LA: (25.1 +/- 3.4) microm; RA: (25.2 +/- 3.5) microm] than sham-operated group [LA: (19.6 +/- 2.9) microm; RA: (18.7 +/- 2.6) microm] (P benazepril group than AF group [LA: (11.3 +/- 0.8)% vs (16.9 +/- 1.1)%, RA: (10.9 +/- 0.8)% vs (15.7 +/- 2.3)%, P benazepril group than AF group (P benazepril group than AF group (LA:0.8 +/- 0.4 vs 1.0 +/- 0.3, 0.7 +/- 0.3 vs 0.9 +/- 0.4; RA:0.7 +/- 0.3 vs 1.0 +/- 0.6, 0.7 +/- 0.3 vs 1.1 +/- 0.3, P Benazepril can favorably improve atrial cytoskeleton remodeling in the canine atrial fibrillation model.

Risk of pacemaker implantation after uneventful successful cavotricuspid isthmus radiofrequency ablation in patients with common atrial flutter.

Science.gov (United States)

Rodríguez-Mañero, Moisés; González-Melchor, Layla; Ballesteros, Gabriel; Raposeiras-Roubín, Sergio; García-Seara, Javier; López, Xesús Alberte Fernández; Cambeiro, Cristina González; Alcalde, Oscar; García-Bolao, Ignacio; Martínez-Sande, Luis; González-Juanatey, José Ramón

2016-01-01

Little is known about the risk of pacemaker implantation after common atrial flutter ablation in the long-term. We retrospectively reviewed the electrophysiology laboratory database at two Spanish University Hospitals from 1998 to 2012 to identify patients who had undergone successful ablation for cavotricuspid dependent atrial flutter. Cox regression analysis was used to examine the risk of pacemaker implantation. A total of 298 patients were considered eligible for inclusion. The mean age of the enrolled patients was 65.7±11. During 57.7±42.8 months, 30 patients (10.1%) underwent pacemaker implantation. In the stepwise multivariate models only heart rate at the time of the ablation (OR: 0.96; 95% CI: 0.93-0.98; ppacemaker implantation. A heart rate of ≤65 bpm was identified as the optimal cut-off value to predict the need of pacemaker implantation in the follow-up (sensitivity: 79%, specificity: 74%) by ROC curve analyses. This is the first study of an association between the slow conducting common atrial flutter and subsequent risk of pacemaker implantation. In light of these findings, assessing it prior to ablation can be helpful for the risk stratification of sinus node disease or atrioventricular conduction disease requiring a pacemaker implantation in patients with persistent atrial flutter. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Typical atrial flutter: Diagnosis and therapy].

Science.gov (United States)

Thomas, Dierk; Eckardt, Lars; Estner, Heidi L; Kuniss, Malte; Meyer, Christian; Neuberger, Hans-Ruprecht; Sommer, Philipp; Steven, Daniel; Voss, Frederik; Bonnemeier, Hendrik

2016-03-01

Typical, cavotricuspid-dependent atrial flutter is the most common atrial macroreentry tachycardia. The incidence of atrial flutter (typical and atypical forms) is age-dependent with 5/100,000 in patients less than 50 years and approximately 600/100,000 in subjects > 80 years of age. Concomitant heart failure or pulmonary disease further increases the risk of typical atrial flutter.Patients with atrial flutter may present with symptoms of palpitations, reduced exercise capacity, chest pain, or dyspnea. The risk of thromboembolism is probably similar to atrial fibrillation; therefore, the same antithrombotic prophylaxis is required in atrial flutter patients. Acutely symptomatic cases may be subjected to cardioversion or pharmacologic rate control to relieve symptoms. Catheter ablation of the cavotricuspid isthmus represents the primary choice in long-term therapy, associated with high procedural success (> 97 %) and low complication rates (0.5 %).This article represents the third part of a manuscript series designed to improve professional education in the field of cardiac electrophysiology. Mechanistic and clinical characteristics as well as management of isthmus-dependent atrial flutter are described in detail. Electrophysiological findings and catheter ablation of the arrhythmia are highlighted.

Radiofrequency catheter oblation in atrial flutter

International Nuclear Information System (INIS)

Yan Ji; Wang Heping; Xu Jian; Liu Fuyuan; Fan Xizhen; An Chunsheng; Han Xiaoping; Ding Xiaomei; Wang Jiasheng; Gu Tongyuan

2002-01-01

Objective: To evaluate the radiofrequency catheter ablation for type I atrial flutter through application of Holo catheter labelling with anatomic imaging localization to ablate the isthmus of IVCTA during complete double-way block. Methods: Eleven cases with type I atrial flutter undergone Holo catheter labelling technique and consecution with conduction time change of coronary venous sinus orifice with-right atrial lower lateral wall pace excitation, were performed with radiofrequency catheter ablation for the isthmus outcoming with complete double-way conduction block. Results: All together 11 cases with 4 of atrial flutter and 7 of sinus rhythm were undergone radiofrequency catheter ablation resulting with double-way conduction block of the isthmus accompanied by prolongation of right atrial conduction time 56.0 ± 2.3 ms and 53.0 ± 4.6 ms respectively. The right atrial excitation appeared to be in clockwise and counter-clockwise of single direction. No recurrence occurred during 3-34 months follow up with only one showing atrial fibrillation. Conclusions: The application of Holo catheter labelling technique with anatomic imaging localization to achieve the double-way conduction block by radiofrequency catheter ablation of TVC-TA isthmus, is a reliable method for treating atrial flutter

Valsartan Reduced Atrial Fibrillation Susceptibility by Inhibiting Atrial Parasympathetic Remodeling through MAPKs/Neurturin Pathway

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Lei Liu

2015-07-01

Full Text Available Background/Aims: Angiotensin II receptor blockers (ARBs have been proved to be effective in preventing atrial structural and electrical remodelinq in atrial fibrillation (AF. Previous studies have shown that parasympathetic remodeling plays an important role in AF. However, the effects of ARBs on atrial parasympathetic remodeling in AF and the underlying mechanisms are still unknown. Methods: Canines were divided into sham-operated, pacing and valsartan + pacing groups. Rats and HL-1 cardiomyocytes were divided into control, angiotensin II (Ang II and Ang II + valsartan groups, respectively. Atrial parasympathetic remodeling was quantified by immunocytochemical staining with anti-choline acetyltransferase (ChAT antibody. Western blot was used to analysis the protein expression of neurturin. Results: Both inducibility and duration were increased in chronic atrial rapid-pacing canine model, which was significantly inhibited by the treatment with valsartan. The density of ChAT-positive nerves and the protein level of neurturin in the atria of pacing canines were both increased than those in sham-operated canines. Ang II treatment not only induced atrial parasympathetic remodeling in rats, but also up-regulated the protein expression of neurturin. Valsartan significantly prevented atrial parasympathetic remodeling, and suppressed the protein expression of neurturin. Meanwhile, valsartan inhibited Ang II -induced up-regulation of neurturin and MAPKs in cultured cardiac myocytes. Inhibition of MAPKs dramatically attenuated neurturin up-regulation induced by Ang II. Conclusion: Parasympathetic remodeling was present in animals subjected to rapid pacing or Ang II infusion, which was mediated by MAPKs/neurturin pathway. Valsartan is able to prevent atrial parasympathetic remodeling and the occurrence of AF via inhibiting MAPKs/neurturin pathway.

Valsartan Reduced Atrial Fibrillation Susceptibility by Inhibiting Atrial Parasympathetic Remodeling through MAPKs/Neurturin Pathway.

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Liu, Lei; Geng, Jianqiang; Zhao, Hongwei; Yun, Fengxiang; Wang, Xiaoyu; Yan, Sen; Ding, Xue; Li, Wenpeng; Wang, Dingyu; Li, Jianqiang; Pan, Zhenwei; Gong, Yongtai; Tan, Xiangyang; Li, Yue

2015-01-01

Angiotensin II receptor blockers (ARBs) have been proved to be effective in preventing atrial structural and electrical remodelinq in atrial fibrillation (AF). Previous studies have shown that parasympathetic remodeling plays an important role in AF. However, the effects of ARBs on atrial parasympathetic remodeling in AF and the underlying mechanisms are still unknown. Canines were divided into sham-operated, pacing and valsartan + pacing groups. Rats and HL-1 cardiomyocytes were divided into control, angiotensin II (Ang II) and Ang II + valsartan groups, respectively. Atrial parasympathetic remodeling was quantified by immunocytochemical staining with anti-choline acetyltransferase (ChAT) antibody. Western blot was used to analysis the protein expression of neurturin. Both inducibility and duration were increased in chronic atrial rapid-pacing canine model, which was significantly inhibited by the treatment with valsartan. The density of ChAT-positive nerves and the protein level of neurturin in the atria of pacing canines were both increased than those in sham-operated canines. Ang II treatment not only induced atrial parasympathetic remodeling in rats, but also up-regulated the protein expression of neurturin. Valsartan significantly prevented atrial parasympathetic remodeling, and suppressed the protein expression of neurturin. Meanwhile, valsartan inhibited Ang II -induced up-regulation of neurturin and MAPKs in cultured cardiac myocytes. Inhibition of MAPKs dramatically attenuated neurturin up-regulation induced by Ang II. Parasympathetic remodeling was present in animals subjected to rapid pacing or Ang II infusion, which was mediated by MAPKs/neurturin pathway. Valsartan is able to prevent atrial parasympathetic remodeling and the occurrence of AF via inhibiting MAPKs/neurturin pathway. © 2015 S. Karger AG, Basel.

An improved in vivo method for atrioventricular node ablation via thoracotomy

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R.H. MacIver

2010-02-01

Full Text Available The atrioventricular (AV node is permanently damaged in approximately 3% of congenital heart surgery operations, requiring implantation of a permanent pacemaker. Improvements in pacemaker design and in alternative treatment modalities require an effective in vivo model of complete heart block (CHB before testing can be performed in humans. Such a model should enable accurate, reliable, and detectable induction of the surgical pathology. Through our laboratory’s efforts in developing a tissue engineering therapy for CHB, we describe here an improved in vivo model for inducing chronic AV block. The method employs a right thoracotomy in the adult rabbit, from which the right atrial appendage may be retracted to expose an access channel for the AV node. A novel injection device was designed, which both physically restricts needle depth and provides electrical information via electrocardiogram interface. This combination of features provides real-time guidance to the researcher for confirming contact with the AV node, and documents its ablation upon formalin injection. While all animals tested could be induced to acute AV block, those with ECG guidance were more likely to maintain chronic heart block >12 h. Our model enables the researcher to reproduce both CHB and the associated peripheral fibrosis that would be present in an open congenital heart surgery, and which would inevitably impact the design and utility of a tissue engineered AV node replacement.

Fuelling Insecurity? Sino-Myanmar Energy Cooperation and Human Security in Myanmar

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Botel, Gabriel

This thesis examines the relationship between energy, development and human security in Sino-Myanmar relations. Rapid economic growth and increased urbanisation have intensified China's industrial and domestic energy consumption, drastically increasing demand and overwhelming national supply capacities. Chinese foreign policy has responded by becoming more active in securing and protecting foreign energy resources and allowing Chinese companies more freedom and opportunities for investment abroad. Consequently, Chinese foreign investment and policies have become increasing sources of scrutiny and debate, typically focusing on their (presumed) intentions and the social, economic, environmental and political impacts they have on the rest of the world. Within this debate, a key issue has been China's engagement with so-called pariah states. China has frequently received substantial international criticism for its unconditional engagement with such countries, often seen as a geopolitical pursuit of strategic national (energy) interests, unconcerned with international opprobrium. In the case of Myanmar, traditional security analyses interpret this as, at best, undermining (Western) international norms and, at worst, posing a direct challenge to international security. However, traditional security analyses rely on state-centric concepts of security, and tend to over-simply Sino-Myanmar relations and the dynamics which inform it. Conversely, implications for human security are overlooked; this is in part because human security remains poorly defined and also because there are questions regarding its utility. However, human security is a critical tool in delineating between state, corporate and 'civilian' interests, and how these cleavages shape the security environment and potential for instability in the region. This thesis takes a closer look at some of the entrenched and changing security dynamics shaping this Sino-Myanmar energy cooperation, drawing on an extensive

Occlusion of left atrial appendage in patients with atrial fibrillation

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О. Н. Ганеева

2015-10-01

Full Text Available The article reviews a new method of prophylaxis of thromboembolitic complications, specifically occlusion of left atrial appendage, in patients with atrial fibrillation. Indications and contraindications for the procedure, as well as a step-by-step process of the intervention itself are described. Special emphasis is placed on the up-to-date evidence and the review of clinical trials.

Atrial fibrillation or flutter

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... this page: //medlineplus.gov/ency/article/000184.htm Atrial fibrillation or flutter To use the sharing features on this page, please enable JavaScript. Atrial fibrillation or flutter is a common type of abnormal ...

Impact of Variations in Kidney Function on Nonvitamin K Oral Anticoagulant Dosing in Patients With Atrial Fibrillation and Recent Acute Heart Failure.

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Andreu-Cayuelas, José M; Pastor-Pérez, Francisco J; Puche, Carmen M; Mateo-Martínez, Alicia; García-Alberola, Arcadio; Flores-Blanco, Pedro J; Valdés, Mariano; Lip, Gregory Y H; Roldán, Vanessa; Manzano-Fernández, Sergio

2016-02-01

Renal impairment and fluctuations in renal function are common in patients recently hospitalized for acute heart failure and in those with atrial fibrillation. The aim of the present study was to evaluate the hypothetical need for dosage adjustment (based on fluctuations in kidney function) of dabigatran, rivaroxaban and apixaban during the first 6 months after hospital discharge in patients with concomitant atrial fibrillation and heart failure. An observational study was conducted in 162 patients with nonvalvular atrial fibrillation after hospitalization for acute decompensated heart failure who underwent creatinine determinations during follow-up. The hypothetical recommended dosage of dabigatran, rivaroxaban and apixaban according to renal function was determined at discharge. Variations in serum creatinine and creatinine clearance and consequent changes in the recommended dosage of these drugs were identified during 6 months of follow-up. Among the overall study population, 44% of patients would have needed dabigatran dosage adjustment during follow-up, 35% would have needed rivaroxaban adjustment, and 29% would have needed apixaban dosage adjustment. A higher proportion of patients with creatinine clearance renal impairment. Further studies are needed to clarify the clinical importance of these needs for drug dosing adjustment and the ideal renal function monitoring regime in heart failure and other subgroups of patients with atrial fibrillation. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Atrial conduction times and left atrial mechanical functions and their relation with diastolic function in prediabetic patients.

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Gudul, Naile Eris; Karabag, Turgut; Sayin, Muhammet Rasit; Bayraktaroglu, Taner; Aydin, Mustafa

2017-03-01

The aim of this study was to investigate atrial conduction times and left atrial mechanical functions, the noninvasive predictors of atrial fibrillation, in prediabetic patients with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). Study included 59 patients (23 males, 36 females; mean age 52.5 ± 10.6 years) diagnosed with IFG or IGT by the American Diabetes Association criteria, and 43 healthy adults (22 males, 21 females; mean age 48.5 ± 12.1 years). Conventional and tissue Doppler echocardiography were performed. The electromechanical delay parameters were measured from the onset of the P wave on the surface electrocardiogram to the onset of the atrial systolic wave on tissue Doppler imaging from septum, lateral, and right ventricular annuli. The left atrial volumes were calculated by the disk method. Left atrial mechanical functions were calculated. The mitral E/A and E'/A' ratios measured from the lateral and septal annuli were significantly lower in the prediabetics compared to the controls. The interatrial and left atrial electromechanical delay were significantly longer in prediabetic group compared to the controls. Left atrial active emptying volume (LAAEV) and fraction (LAAEF) were significantly higher in the prediabetics than the controls. LAAEV and LAAEF were significantly correlated with E/A, lateral and septal E'/A'. In the prediabetic patients, the atrial conduction times and P wave dispersion on surface electrocardiographic were longer before the development of overt diabetes. In addition, the left atrial mechanical functions were impaired secondary to a deterioration in the diastolic functions in the prediabetic patients.

Genetics Home Reference: familial atrial fibrillation

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... Twitter Home Health Conditions Familial atrial fibrillation Familial atrial fibrillation Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Familial atrial fibrillation is an inherited abnormality of the heart's normal ...

The Rio dos Sinos watershed: an economic and social space and its interface with environmental status

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JAS. Figueiredo

Full Text Available The Rio dos Sinos watershed is located in the eastern region of the state of Rio Grande do Sul and includes 32municipalities. These municipalities develop several different economic activities such as farming and livestock along the 190 km length of the Rio dos Sinos, one of the rivers with the worst quality of water in Brazil. The region is also characterised by growing urbanisation and heavy industrialisation. The main economic activity is the leather and footwear industry. This diversified land use puts the Rio dos Sinos watershed at risk of a wide range of potential environmental impacts. The aim of the present article is to discuss the socioeconomic process currently implemented in the Rio dos Sinos watershed and the effect of these human actions on the environmental quality described throughout this special issue of the Brazilian Journal of Biology.

History of water quality parameters - a study on the Sinos River/Brazil.

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Konzen, G B; Figueiredo, J A S; Quevedo, D M

2015-05-01

Water is increasingly becoming a valuable resource, constituting one of the central themes of environmental, economic and social discussions. The Sinos River, located in southern Brazil, is the main river from the Sinos River Basin, representing a source of drinking water supply for a highly populated region. Considering its size and importance, it becomes necessary to conduct a study to follow up the water quality of this river, which is considered by some experts as one of the most polluted rivers in Brazil. As for this study, its great importance lies in the historical analysis of indicators. In this sense, we sought to develop aspects related to the management of water resources by performing a historical analysis of the Water Quality Index (WQI) of the Sinos River, using statistical methods. With regard to the methodological procedures, it should be pointed out that this study performs a time analysis of monitoring data on parameters related to a punctual measurement that is variable in time, using statistical tools. The data used refer to analyses of the water quality of the Sinos River (WQI) from the State Environmental Protection Agency Henrique Luiz Roessler (Fundação Estadual de Proteção Ambiental Henrique Luiz Roessler, FEPAM) covering the period between 2000 and 2008, as well as to a theoretical analysis focusing on the management of water resources. The study of WQI and its parameters by statistical analysis has shown to be effective, ensuring its effectiveness as a tool for the management of water resources. The descriptive analysis of the WQI and its parameters showed that the water quality of the Sinos River is concerning low, which reaffirms that it is one of the most polluted rivers in Brazil. It should be highlighted that there was an overall difficulty in obtaining data with the appropriate periodicity, as well as a long complete series, which limited the conduction of statistical studies such as the present one.

[Atrial fibrillation].

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Spinar, J; Vítovec, J

2003-09-01

Atrial fibrilation is the most frequent arrhythmia, the occurrence increasing with age and associated diseases. The incidence at the age below 60 years is markedly lower than one per cent, whereas in persons above 80 years of age it exceeds six per cent. The occurrence in patients with heart failure is from 10% (NYHA II) up to 50% (NYHA IV). Atrial fibrillation is classified into that observed for the first time and permanent, respectively, while transient forms include paroxyzmal and persistent atrial fibrillation. The diagnosis is based on ECG recording, while echocardiography is most significant. The therapy includes two basic questions--anticoagulant or anti-aggregation treatment and the control of rhythm or frequency. The anticoagulant therapy should be introduced in all patients, where contraindications are not present, being necessary before every cardioversion, provided atrial fibrillation lasts more than two days. In patients without any heart disease and with a physiological echocardiogram it is possible to administer only anti-aggregation treatment. Cardioversion (the control of rhythm) is recommended to all symptomatic patients, in other cases and especially in older persons the control of frequency is safer and of more advantage. Electrical cardioversion is more effective that a pharmacological treatment, the sinus rhythm is preferably controlled by dofetilid, ibutilid, propafenon and amiodaron. For the control of heart rate beta-blockers, diltiazem, verapamil and digitalis are recommended.

Torsades de Pointes associated with QT prolongation after catheter ablation of paroxysmal atrial fibrillation

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Yae Min Park

2017-09-01

Full Text Available A 79-year-old woman who underwent catheter ablation for paroxysmal atrial fibrillation presented with Torsades de Pointes (TdP. Aggravation of prolonged QT interval which is most likely due to neural modulation by catheter ablation, played major role in the initiation of TdP. The patient was successfully treated with isoproterenol during acute stage and discharged after stabilization without implantation of permanent pacemaker or implantable cardioverter defibrillator.

Atrial Fibrillation - Multiple Languages

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... Are Here: Home → Multiple Languages → All Health Topics → Atrial Fibrillation URL of this page: https://medlineplus.gov/languages/ ... V W XYZ List of All Topics All Atrial Fibrillation - Multiple Languages To use the sharing features on ...

Left atrial low-voltage areas predict atrial fibrillation recurrence after catheter ablation in patients with paroxysmal atrial fibrillation.

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Masuda, Masaharu; Fujita, Masashi; Iida, Osamu; Okamoto, Shin; Ishihara, Takayuki; Nanto, Kiyonori; Kanda, Takashi; Tsujimura, Takuya; Matsuda, Yasuhiro; Okuno, Shota; Ohashi, Takuya; Tsuji, Aki; Mano, Toshiaki

2018-04-15

Association between the presence of left atrial low-voltage areas and atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) has been shown mainly in persistent AF patients. We sought to compare the AF recurrence rate in paroxysmal AF patients with and without left atrial low-voltage areas. This prospective observational study included 147 consecutive patients undergoing initial ablation for paroxysmal AF. Voltage mapping was performed after PVI during sinus rhythm, and low-voltage areas were defined as regions where bipolar peak-to-peak voltage was low-voltage areas after PVI were observed in 22 (15%) patients. Patients with low-voltage areas were significantly older (72±6 vs. 66±10, plow-voltage areas than without (36% vs. 6%, pLow-voltage areas were independently associated with AF recurrence even after adjustment for the other related factors (Hazard ratio, 5.89; 95% confidence interval, 2.16 to 16.0, p=0.001). The presence of left atrial low-voltage areas after PVI predicts AF recurrence in patients with paroxysmal AF as well as in patients with persistent AF. Copyright © 2017 Elsevier B.V. All rights reserved.

Atrial-selective K+ channel blockers: potential antiarrhythmic drugs in atrial fibrillation?

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Ravens, Ursula

2017-11-01

In the wake of demographic change in Western countries, atrial fibrillation has reached an epidemiological scale, yet current strategies for drug treatment of the arrhythmia lack sufficient efficacy and safety. In search of novel medications, atrial-selective drugs that specifically target atrial over other cardiac functions have been developed. Here, I will address drugs acting on potassium (K + ) channels that are either predominantly expressed in atria or possess electrophysiological properties distinct in atria from ventricles. These channels include the ultra-rapidly activating, delayed outward-rectifying Kv1.5 channel conducting I Kur , the acetylcholine-activated inward-rectifying Kir3.1/Kir3.4 channel conducting I K,ACh , the Ca 2+ -activated K + channels of small conductance (SK) conducting I SK , and the two-pore domain K + (K2P) channels (tandem of P domains, weak inward-rectifying K + channels (TWIK-1), TWIK-related acid-sensitive K + channels (TASK-1 and TASK-3)) that are responsible for voltage-independent background currents I TWIK-1 , I TASK-1 , and I TASK-3 . Direct drug effects on these channels are described and their putative value in treatment of atrial fibrillation is discussed. Although many potential drug targets have emerged in the process of unravelling details of the pathophysiological mechanisms responsible for atrial fibrillation, we do not know whether novel antiarrhythmic drugs will be more successful when modulating many targets or a single specific one. The answer to this riddle can only be solved in a clinical context.

Association of Atrial Fibrillation with Morphological and Electrophysiological Changes of the Atrial Myocardium.

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Matějková, Adéla; Šteiner, Ivo

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. For long time it was considered as pure functional disorder, but in recent years, there were identified atrial locations, which are involved in the initiation and maintenance of this arrhythmia. These structural changes, so called remodelation, start at electric level and later they affect contractility and morphology. In this study we attempted to find a possible relation between morphological (scarring, amyloidosis, left atrial (LA) enlargement) and electrophysiological (ECG features) changes in patients with AF. We examined grossly and histologically 100 hearts of necropsy patients - 54 with a history of AF and 46 without AF. Premortem ECGs were evaluated. The patients with AF had significantly heavier heart, larger LA, more severely scarred myocardium of the LA and atrial septum, and more severe amyloidosis in both atria. Severity of amyloidosis was higher in LAs vs. right atria (RAs). Distribution of both fibrosis and amyloidosis was irregular. The most affected area was in the LA anterior wall. Patients with a history of AF and with most severe amyloidosis have more often abnormally long P waves. Finding of long P wave may contribute to diagnosis of a hitherto undisclosed atrial fibrillation.

ANTIARRHYTMIC EFFICACY OF SOTALOL IN PATIENTS WITH TACHY-BRADY SYNDROME HAVING ATRIAL PACEMAKER WITH DIFFERENT ATRIAL ELECTRODE POSITION

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T. N. Novikova

2009-01-01

Full Text Available Aim. To evaluate efficacy of the combined therapy (sotalol and constant electric cardiostimulation in AAI regimen at two atrial electrode position: in low back part of interatrial septum (IAS and in right atrial auricle (RAA.Material and methods. 20 patients with tachy-brady syndrome were examined. They were randomized in 2 groups depending on atrial electrode position. Sotalol (160 mg daily was prescribed to all patients in a month after implantation of constant atrial pacemaker (CAP. A number of atrial fibrillation paroxysms (AFP was evaluated initially, in a month after CAP implantation and in a month after start of sotalol therapy.Results. Significant AFP reduction was observed in IAS stimulation, unlike RAA stimulation. Sotalol addition had essential significance in the termination or reduction of AFP. Sotalol effect did not depend on atrial electrode position.Conclusion. Sotalol usage together with constant electric cardiostimulation significantly reduces AFP irrespectively of atrial electrode position. 

The Sino-Indian Border: Is Conflict Inevitable?

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2013-12-13

relationship between China and India may be thought in terms of a gestalt theory . The basis of the gestalt theory is that before perceiving different...greater than the sum of the parts” is often used to explain gestalt theory .33 Analysts on both sides often view their relations as the sum of border...Most often, hawkish views grab the headlines.”56 This adds to the Sino-Indian gestalt and form perception about each other based on viewpoints of

Effect of age on stroke prevention therapy in patients with atrial fibrillation: the atrial fibrillation investigators

DEFF Research Database (Denmark)

van Walraven, Carl; Hart, Robert G; Connolly, Stuart

2009-01-01

contains patient level-data from randomized trials of stroke prevention in atrial fibrillation. We used Cox regression models with age as a continuous variable that controlled for sex, year of randomization, and history of cerebrovascular disease, diabetes, hypertension, and congestive heart failure......BACKGROUND AND PURPOSE: Stroke risk increases with age in patients who have nonvalvular atrial fibrillation. It is uncertain whether the efficacy of stroke prevention therapies in atrial fibrillation changes as patients age. The objective of this study was to determine the effect of age...... on the relative efficacy of oral anticoagulants (OAC) and antiplatelet (AP) therapy (including acetylsalicylic acid and triflusal) on ischemic stroke, serious bleeding, and vascular events in patients with atrial fibrillation. METHODS: This is an analysis of the Atrial Fibrillation Investigators database, which...

The Limits of Interdependence: Cooperation and Conflict in Sino-Japanese Relations

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Adam Eldridge

2014-01-01

Full Text Available Since the introduction of Deng Xiaoping’s Open Door policy in 1979, the value and complexity of Sino-Japanese economic ties have grown exponentially. However, even as economic ties have developed, security relations have deteriorated as perceptions of a ‘China threat’ and a ‘re-militarised Japan’ have emerged in Tokyo and Beijing. The simultaneous existence of these trends challenges international relations theory. Economic interdependence theories expect that the development of economic relations reduces the role of security in bilateral relations. Conversely, neorealist theories posit that, given the preeminence of national security, a perception of threat will cool economic relations. Sino-Japanese economic relations have demonstrable bilateral benefits. Additionally, economic relations have created interest groups invested in maintaining good relations. These groups have successfully managed economic friction points and integrated bilateral trade. However, economic interdependence seems not to translate to the security calculus confirming neorealism’s contention that national security is preeminent. In particular, Japan’s development of Ballistic Missile Defence (BMD illustrates the insignificance of economic ties in security planning. That said, it is equally true that perceptions of threat appear to have little influence on bilateral economic interdependence. Therefore, Sino-Japanese relations are best described by applying interdependence and neorealist theories in a complementary approach.

Inter-subject variability in human atrial action potential in sinus rhythm versus chronic atrial fibrillation.

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Carlos Sánchez

Full Text Available Human atrial electrophysiology exhibits high inter-subject variability in both sinus rhythm (SR and chronic atrial fibrillation (cAF patients. Variability is however rarely investigated in experimental and theoretical electrophysiological studies, thus hampering the understanding of its underlying causes but also its implications in explaining differences in the response to disease and treatment. In our study, we aim at investigating the ability of populations of human atrial cell models to capture the inter-subject variability in action potential (AP recorded in 363 patients both under SR and cAF conditions.Human AP recordings in atrial trabeculae (n = 469 from SR and cAF patients were used to calibrate populations of computational SR and cAF atrial AP models. Three populations of over 2000 sampled models were generated, based on three different human atrial AP models. Experimental calibration selected populations of AP models yielding AP with morphology and duration in range with experimental recordings. Populations using the three original models can mimic variability in experimental AP in both SR and cAF, with median conductance values in SR for most ionic currents deviating less than 30% from their original peak values. All cAF populations show similar variations in G(K1, G(Kur and G(to, consistent with AF-related remodeling as reported in experiments. In all SR and cAF model populations, inter-subject variability in I(K1 and I(NaK underlies variability in APD90, variability in I(Kur, I(CaL and I(NaK modulates variability in APD50 and combined variability in Ito and I(Kur determines variability in APD20. The large variability in human atrial AP triangulation is mostly determined by I(K1 and either I(NaK or I(NaCa depending on the model.Experimentally-calibrated human atrial AP models populations mimic AP variability in SR and cAF patient recordings, and identify potential ionic determinants of inter-subject variability in human atrial AP

Surface atrial frequency analysis in patients with atrial fibrillation: a tool for evaluating the effects of intervention.

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Raine, Dan; Langley, Philip; Murray, Alan; Dunuwille, Asunga; Bourke, John P

2004-09-01

The aims of this study were to evaluate (1) principal component analysis as a technique for extracting the atrial signal waveform from the standard 12-lead ECG and (2) its ability to distinguish changes in atrial fibrillation (AF) frequency parameters over time and in response to pharmacologic manipulation using drugs with different effects on atrial electrophysiology. Twenty patients with persistent AF were studied. Continuous 12-lead Holter ECGs were recorded for 60 minutes, first, in the drug-free state. Mean and variability of atrial waveform frequency were measured using an automated computer technique. This extracted the atrial signal by principal component analysis and identified the main frequency component using Fourier analysis. Patients were then allotted sequentially to receive 1 of 4 drugs intravenously (amiodarone, flecainide, sotalol, or metoprolol), and changes induced in mean and variability of atrial waveform frequency measured. Mean and variability of atrial waveform frequency did not differ within patients between the two 30-minute sections of the drug-free state. As hypothesized, significant changes in mean and variability of atrial waveform frequency were detected after manipulation with amiodarone (mean: 5.77 vs 4.86 Hz; variability: 0.55 vs 0.31 Hz), flecainide (mean: 5.33 vs 4.72 Hz; variability: 0.71 vs 0.31 Hz), and sotalol (mean: 5.94 vs 4.90 Hz; variability: 0.73 vs 0.40 Hz) but not with metoprolol (mean: 5.41 vs 5.17 Hz; variability: 0.81 vs 0.82 Hz). A technique for continuously analyzing atrial frequency characteristics of AF from the surface ECG has been developed and validated.

Network Partnership Diplomatic Mechanism: The New Path in Sino-Russian Cooperation - On the Sino-Russian Joint Dominance of BRICS Governance Mechanism

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Zhijie Cheng

2014-01-01

Full Text Available 成志杰 王 宛 【内容提要】中俄合作是将来一定时期内国际格局变革与发展的决定性力量。但是，中俄关系存在典型的“二律背反”情结：既借重又怀疑,既合作又防范。处理两国关系，除了原有的双边机制外，中俄还可以通过网状伙伴外交机制进行多边机制下的合作。网状伙伴外交机制主要是指中俄在各个相关多边机制内的互动合作，是双方彼此需要、彼此借重，有效处理双边关系，共同应对国际事务的灵活机制。它具有自身的逻辑。加强和深化中俄合作并不意味着中俄要结盟。网状伙伴外交机制的提出更多是中俄合作的新路径，对于缓解中俄关系中竞争与博弈困境、促进相关国际机制发展等具有重要的意义。金砖国家应该建立金砖国家治理型机制。它需要一个主导性力量中心进行推动。网状伙伴外交机制有利于塑造金砖国家机制的主导性力量中心——中俄联合主导，它是金砖国家治理型机制的内涵之一。中俄联合主导将会在金砖国家机制发展中发挥引领作用。 Sino-Russian cooperation will become an important force in reforming and developing the international system in the near future. However, Sino-Russian relations are complicated since the two countries maintain a guarded attitude towards each other even while cooperating extensively. In addition to furthering bilateral relations, China and Russia can also choose to cooperate through multilateral network mechanisms. This provides opportunities for flexible and strategic cooperation and coordination between the two countries. Strengthening and deepening the Sino-Russian cooperation does not imply forming an actual alliance. The network partnership diplomatic mechanism could play an important role in alleviating competition and mistrust between China and Russia, promoting the development of relevant international

Surgical treatment for ectopic atrial tachycardia.

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Graffigna, A; Vigano, M; Pagani, F; Salerno, G

1992-08-01

Atrial tachycardia is an infrequent but potentially dangerous arrhythmia which often determines cardiac enlargement. Surgical ablation of the arrhythmia is effective and safe, provided a careful atrial mapping is performed and the surgical technique is tailored to the individual focus location. Eight patients underwent surgical ablation of ectopic atrial tachycardia between 1977 and 1990. Different techniques were adopted for each patient according to the anatomical location of the focus and possibly associated arrhythmias. Whenever possible, a closed heart procedure was chosen. In 1 patient a double focal origin was found and treated by separate procedures. In 1 patient with ostium secundum atrial septal defect and atrial flutter, surgical isolation of the right appendage and the ectopic focus was performed. In all patients ectopic atrial tachycardia was ablated with maintenance of the sinoatrial and atrioventricular nodal function as well as internodal conduction. In follow-up up to December 1991, no recurrency was recorded.

Histopathologic analysis of atrial tissue in patients with atrial fibrillation: comparison between patients with atrial septal defect and patients with mitral valvular heart disease.

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Kwak, Jae Gun; Seo, Jeong-Wook; Oh, Sam Se; Lee, Sang Yun; Ham, Eui Keun; Kim, Woong-Han; Kim, Soo-Jin; Bae, Eun Jung; Lim, Cheoung; Lee, Chang-Ha; Lee, Cheul

2014-01-01

Atrial fibrillation (AF) in adult patients with atrial septal defect (ASD) accompanies an enlarged right atrium (RA) with a less enlarged left atrium (LA), which is the opposite situation in patients with AF and mitral valvular disease. This study was to compare the histopathological change in the atrium of patients with AF of two different etiologies: ASD and mitral disease. Twenty-four patients were enrolled. Group 1 included patients with ASD (8), Group 2 included patients with ASD with AF (6), and Group 3 included patients with mitral disease with AF (10). Preoperative atrial volumes were measured. Atrial tissues were obtained during surgical procedures and stained with periodic acid-Schiff, smooth muscle actin, Sirius red, and Masson's trichrome to detect histopathologic changes compatible with AF. The severity of histopathological changes was represented with "positivity" and "strong positivity" after analyzing digitalized images of the staining. We investigated the relationship between the degree of atrial dilatation and severity of histopathological changes according to the groups and tissues. Group 2 and Group 3 patients showed a tendency toward an enlarged RA volume and enlarged LA volume, respectively, compared with each others. However, in the histopathologic analysis, "positivity" and "strong positivity" showed no significant positive correlations with the degree of atrial volume in special staining. A similar degree of histopathologic changes was observed in both atria in patients with AF (Group 2 and 3) regardless of the degree of dilatation of atrial volume and disease entities. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

[Quantitative Measurements on the Blood Flow Fields of Left Atrial Appendage using Vector Flow Mapping in Patients with Nonvalvular Atrial Fibrillation].

Science.gov (United States)

Cai, Yu-Yan; Wei, Xin; Zhang, Xiao-Ling; Liu, Gu-Yue; Li, Xi; Tang, Hong

2018-01-01

To quantify the hemodynamic characteristics of patients with nonvalvular atrial fibrillation. Twenty patients with paroxysmal atrial fibrillation and 15 patients with persistent atrial fibrillation enrolled in this study,while 12 patients with sinus rhythms served as controls. The hemodynamic characteristics of the patients in left atrial appendage were measured by transesophageal echocardiography (TEE) and vector flow mapping (VFM) using indicators such as vectors,vortex and energy loss (EL). ① Significant differences appeared between the patients with atrial fibrillation and the controls in heart rate,size of left atrium,size of left atrial appendage (LAA),and velocities of LAA filling and emptying. ② Regular vectors in LAA in early systole and late diastole were found in the patients with paroxysmal atrial fibrillation and the controls; whereas,irregular vectors with direction alternating were visualized in the whole cardiac cycle in the patients with persistent atrial fibrillation. ③ Small vortexes were observed at the opening of the left atrial appendage in late diastole in the patients with paroxysmal atrial fibrillation and the controls. ④ Peak EL values occurred in early systole and late diastole in the patients with paroxysmal atrial fibrillation and the controls. But the patients with persistent atrial fibrillation had increased EL values over the whole cardiac cycle. VFM can visualize and quantify the hemodynamics of LAA in patients with different heart rhythms. It may provide a new method for assessing atrial fibrillation. CopyrightCopyright© by Editorial Board of Journal of Sichuan University (Medical Science Edition).

Intraoperative Inducibility of Atrial Fibrillation Does Not Predict Early Postoperative Atrial Fibrillation.

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Lanters, Eva A H; Teuwen, Christophe P; Yaksh, Ameeta; Kik, Charles; van der Does, Lisette J M E; Mouws, Elisabeth M J P; Knops, Paul; van Groningen, Nicole J; Hokken, Thijmen; Bogers, Ad J J C; de Groot, Natasja M S

2018-03-10

Early postoperative atrial fibrillation (EPoAF) is associated with thromboembolic events, prolonged hospitalization, and development of late PoAF (LPoAF). It is, however, unknown if EPoAF can be predicted by intraoperative AF inducibility. The aims of this study are therefore to explore (1) the value of intraoperative inducibility of AF for development of both EPoAF and LPoAF and (2) the predictive value of de novo EPoAF for recurrence of LPoAF. Patients (N=496, 75% male) undergoing cardiothoracic surgery for coronary and/or valvular heart disease were included. AF induction was attempted by atrial pacing, before extracorporeal circulation. All patients were on continuous rhythm monitoring until discharge to detect EPoAF. During a follow-up period of 2 years, LPoAF was detected by ECGs and Holter recordings. Sustained AF was inducible in 56% of patients. There was no difference in patients with or without AF before surgery ( P =0.159), or between different types of surgery ( P =0.687). In patients without a history of AF, incidence of EPoAF and LPoAF was 37% and 2%, respectively. EPoAF recurred in 58% patients with preoperative AF, 53% developed LPoAF. There were no correlations between intraoperative inducibility and EPoAF or LPoAF ( P >0.05). EPoAF was not correlated with LPoAF in patients without a history of AF ( P =0.116), in contrast to patients with AF before surgery ( P <0.001). Intraoperative AF inducibility does not predict development of either EPoAF or LPoAF. In patients with AF before surgery, EPoAF is correlated with LPoAF recurrences. This correlation is absent in patients without AF before surgery. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Fibrosis and electrophysiological characteristics of the atrial appendage in patients with atrial fibrillation and structural heart disease

NARCIS (Netherlands)

Brakel, T.J. van; Krieken, T. van der; Westra, S.W.; Laak, J.A.W.M. van der; Smeets, J.L.R.M.; Swieten, H.A. van

2013-01-01

PURPOSE: This study was conducted to investigate the degree of fibrosis in atrial appendages of patients with and without atrial fibrillation (AF) undergoing cardiac surgery. In addition, we hypothesized that areas of atrial fibrosis can be identified by electrogram fractionation and low voltage for

Atrial overexpression of angiotensin-converting enzyme 2 improves the canine rapid atrial pacing-induced structural and electrical remodeling. Fan, ACE2 improves atrial substrate remodeling.

Science.gov (United States)

Fan, Jinqi; Zou, Lili; Cui, Kun; Woo, Kamsang; Du, Huaan; Chen, Shaojie; Ling, Zhiyu; Zhang, Quanjun; Zhang, Bo; Lan, Xianbin; Su, Li; Zrenner, Bernhard; Yin, Yuehui

2015-01-01

The purpose of this study was to investigate whether atrial overexpression of angiotensin-converting enzyme 2 (ACE2) by homogeneous transmural atrial gene transfer can reverse atrial remodeling and its mechanisms in a canine atrial-pacing model. Twenty-eight mongrel dogs were randomly divided into four groups: Sham-operated, AF-control, gene therapy with adenovirus-enhanced green fluorescent protein (Ad-EGFP) and gene therapy with Ad-ACE2 (Ad-ACE2) (n = 7 per subgroup). AF was induced in all dogs except the Sham-operated group by rapid atrial pacing at 450 beats/min for 2 weeks. Ad-EGFP and Ad-ACE2 group then received epicardial gene painting. Three weeks after gene transfer, all animals except the Sham group underwent rapid atrial pacing for another 3 weeks and then invasive electrophysiological, histological and molecular studies. The Ad-ACE2 group showed an increased ACE2 and Angiotensin-(1-7) expression, and decreased Angiotensin II expression in comparison with Ad-EGFP and AF-control group. ACE2 overexpression attenuated rapid atrial pacing-induced increase in activated extracellular signal-regulated kinases and mitogen-activated protein kinases (MAPKs) levels, and decrease in MAPK phosphatase 1(MKP-1) level, resulting in attenuation of atrial fibrosis collagen protein markers and transforming growth factor-β1. Additionally, ACE2 overexpression also modulated the tachypacing-induced up-regulation of connexin 40, down-regulation of connexin 43 and Kv4.2, and significantly decreased the inducibility and duration of AF. ACE2 overexpression could shift the renin-angiotensin system balance towards the protective axis, attenuate cardiac fibrosis remodeling associated with up-regulation of MKP-1 and reduction of MAPKs activities, modulate tachypacing-induced ion channels and connexin remodeling, and subsequently reduce the inducibility and duration of AF.

Prevention of Cerebral Embolism Progression by Emergency Surgery of the Left Atrial Myxoma

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Syuichi Tetsuka

2015-01-01

Full Text Available A 21-year-old woman developed left hemiparesis during work and was hospitalized. Her National Institutes of Health Stroke Scale score was 4. Hyperintense areas in the left basal ganglia, corona radiata, and cortex of the temporal lobe were found by brain diffusion-weighted magnetic resonance imaging, indicating acute cerebral infarction. Echocardiography showed a giant mass of diameter 7 × 4 cm in the left atrium. Therefore, she was diagnosed with cerebral embolism due to a left atrial myxoma. Currently, thrombolytic therapy may continue to be effective because the embolic source may be composed of tumor tissue itself. In case of atrial myxoma, we considered that the use of tPA as emergency treatment in all patients with infarction by atrial myxoma may be questioned. Thus, cardiac tumor extraction was performed the next day after hospitalization without thrombolytic therapy. The excised myxoma measured 7 × 6 × 4 cm. The patient recovered and her neurological symptoms also improved. Furthermore, her National Institutes of Health Stroke Scale score improved to 0. Thirteen days after admission, the patient was discharged from our hospital. Cardiac myxoma is often associated with a high risk of embolic episodes, which emphasizes the need for prompt surgical excision as soon as the diagnosis is confirmed.

[Relations between FANS, PPI and atrial fibrillation].

Science.gov (United States)

Ricci, Fabrizio; De Caterina, Raffaele

2013-05-01

Recent evidence supports the existence of an association between the use of non-steroidal anti-inflammatory drugs and the risk of atrial fibrillation. Anti-inflammatory drugs are widely used for the treatment of systemic inflammatory disorders, and chronic inflammation is a well-known risk factor for the development of myocardial fibrosis. The latter accounts for atrial inhomogeneities of conduction, thus triggering and perpetuating atrial fibrillation. Atrial inflammatory remodeling may therefore be responsible for the higher incidence of atrial fibrillation among patients assuming steroidal and non-steroidal anti-inflammatory drugs because of an underlying inflammatory disorders. Alternative theories contemplate gastroesophageal reflux, which is extremely common during the use of non-steroidal anti-inflammatory drugs and may trigger atrial fibrillation, as mediating the above-mentioned association.

Atrial septal stenting - How I do it?

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Kothandam Sivakumar

2015-01-01

Full Text Available A wide atrial communication is important to maintain hemodynamics in certain forms of congenital and acquired heart defects. In comparison to balloon septostomy or blade septostomy, atrial septal stenting provides a controlled, predictable, and long-lasting atrial communication. It often needs a prior Brockenbrough needle septal puncture to obtain a stable stent position. A stent deployed across a previously dilated and stretched oval foramen or tunnel form of oval foramen carries higher risk of embolization. This review provides technical tips to achieve a safe atrial septal stenting. Even though this is a "How to do it article," an initial discussion about the indications for atrial septal stenting is vital as the resultant size of the atrial septal communication should be tailored for each indication.

Atrial fibrillation and survival in colorectal cancer

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Justin Timothy A

2004-11-01

Full Text Available Abstract Background Survival in colorectal cancer may correlate with the degree of systemic inflammatory response to the tumour. Atrial fibrillation may be regarded as an inflammatory complication. We aimed to determine if atrial fibrillation is a prognostic factor in colorectal cancer. Patients and methods A prospective colorectal cancer patient database was cross-referenced with the hospital clinical-coding database to identify patients who had underwent colorectal cancer surgery and were in atrial fibrillation pre- or postoperatively. Results A total of 175 patients underwent surgery for colorectal cancer over a two-year period. Of these, 13 patients had atrial fibrillation pre- or postoperatively. Atrial fibrillation correlated with worse two-year survival (p = 0.04; log-rank test. However, in a Cox regression analysis, atrial fibrillation was not significantly associated with survival. Conclusion The presence or development of atrial fibrillation in patients undergoing surgery for colorectal cancer is associated with worse overall survival, however it was not found to be an independent factor in multivariate analysis.

Oclusão percutânea do apêndice atrial esquerdo com o Amplatzer Cardiac PlugTM na fibrilação atrial Percutaneous occlusion of left atrial appendage with the Amplatzer Cardiac PlugTM in atrial fibrillation

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Márcio José Montenegro

2012-02-01

Full Text Available Fundamento: A fibrilação atrial está associada a acidentes vasculares embólicos que frequentemente resultam em morte ou invalidez. Eficaz na redução desses eventos, a anticoagulação possui várias limitações e vem sendo amplamente subutilizada. Mais de 90% dos trombos identificados nos portadores de fibrilação atrial sem doença valvar se originam no apêndice atrial esquerdo, cuja oclusão é investigada como uma alternativa à anticoagulação. Objetivo: Determinar a viabilidade da oclusão percutânea do apêndice atrial esquerdo em pacientes com alto risco de eventos embólicos e limitações ao uso de anticoagulação. Métodos: Relatamos a experiência inicial com o Amplatzer Cardiac PlugTM (St. Jude Medical Inc., Saint Paul, Estados Unidos em pacientes com fibrilação atrial não valvar. Foram selecionados pacientes com alto risco de tromboembolia, sangramentos maiores e contraindicações ao uso ou grande labilidade na resposta ao anticoagulante. Os procedimentos foram realizados por via percutânea, sob anestesia geral e com ecocardiografia transesofágica. O desfecho primário foi a presença de complicações periprocedimento e o seguimento programado incluiu reavaliação clínica e ecocardiográfica em 30 dias e por contato telefônico após nove meses. Resultados: Nos cinco pacientes selecionados se conseguiu a oclusão do apêndice atrial esquerdo sem complicações periprocedimento. Não houve eventos clínicos no seguimento. Conclusão: Ensaios clínicos controlados são necessários antes que o fechamento percutâneo do apêndice atrial esquerdo constitua uma alternativa à anticoagulação na fibrilação atrial não associada a doença valvar. Mas o dispositivo se mostrou promissor em pacientes com alto risco de embolia e restrições ao uso de anticoagulantes.Background: Atrial fibrillation is associated with embolic strokes that often result in death or disability. Effective in reducing these events

Assessment of the dynamics of atrial signals and local atrial period series during atrial fibrillation: effects of isoproterenol administration

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Mantica Massimo

2004-10-01

Full Text Available Abstract Background The autonomic nervous system (ANS plays an important role in the genesis and maintenance of atrial fibrillation (AF, but quantification of its electrophysiologic effects is extremely complex and difficult. Aim of the study was to evaluate the capability of linear and non-linear indexes to capture the fine changing dynamics of atrial signals and local atrial period (LAP series during adrenergic activation induced by isoproterenol (a sympathomimetic drug infusion. Methods Nine patients with paroxysmal or persistent AF (aged 60 ± 6 underwent electrophysiological study in which isoproterenol was administered to patients. Atrial electrograms were acquired during i sinus rhythm (SR; ii sinus rhythm during isoproterenol (SRISO administration; iii atrial fibrillation (AF and iv atrial fibrillation during isoproterenol (AFISO administration. The level of organization between two electrograms was assessed by the synchronization index (S, whereas the degree of recurrence of a pattern in a signal was defined by the regularity index (R. In addition, the level of predictability (LP and regularity of LAP series were computed. Results LAP series analysis shows a reduction of both LP and R index during isoproterenol infusion in SR and AF (RSR = 0.75 ± 0.07 RSRISO = 0.69 ± 0.10, p AF = 0.31 ± 0.08 RAFISO = 0.26 ± 0.09, p SR = 99.99 ± 0.001 LPSRISO = 99.97 ± 0.03, p AF = 69.46 ± 21.55 LPAFISO = 55 ± 24.75; p SR = 0.49 ± 0.08 RSRISO = 0.46 ± 0.09 p AF = 0.29 ± 0.09 RAFISO = 0.28 ± 0.08 n.s.. Conclusions The proposed parameters succeeded in discriminating the subtle changes due to isoproterenol infusion during both the rhythms especially when considering LAP series analysis. The reduced value of analyzed parameters after isoproterenol administration could reflect an important pro-arrhythmic influence of adrenergic activation on favoring maintenance of AF.

Between Two Suns. Czechoslovakia and the Sino-Soviet Dispute over the International Communist Movement (1953-1962)

Czech Academy of Sciences Publication Activity Database

Kolenovská, Daniela

2016-01-01

Roč. 4, č. 1 (2016), s. 19-48 ISSN 2336-3142 Institutional support: RVO:68378114 Keywords : Sino-Czechoslovak relations * Sino-Soviet split * Soviet bloc Subject RIV: AB - History OBOR OECD: History (history of science and technology to be 6.3, history of specific sciences to be under the respective headings)

Effects of atrial fibrillation/atrial flutter on the short and medium-term prognosis of patients with acute myocardial infarction

International Nuclear Information System (INIS)

Cui Kejian; Gu Shuiming; Ding Yueyou; Zheng Hongchao; Zhang Yachen; Li Yigang

2008-01-01

Objective: To evaluate the influnce of atrial fibrillation(AF)/atrial flutter on the mortality and prognosis of patients with AMI. Methods: A total of 297 consecutive patients were studied from Jan. 2001 to Dec. 2005 and were categorized into 2 groups according to the presence or absence of AF/atrial flutter. The 30 d and 6 mo mortalities, Killip Grades, cardiogenic shock, arrhythmia and left ventricular ejectory functional (LVEF) 6 months after AMI with Doppler US between the 2 groups were compared. Results: The incidence of AF/atrial fluttler was 12.5% with older age, higher Killip Gorade, higher CPK peak, higher rates of previous myocardial infarction and multivascular involvement than those without AF/ atrial flutter. The short and medium-term mortalities in AF/atriat flutter group were both significantly higher than those of non-AF/atrial flutter group (P<0.05). Conclusions: The short and medium-term mortalities increase obviously in AMI complicated with AF/atrial flutter, probably related to the severity of atherosclerosis. (authors)

Incisional left atrial isolation for ablation of atrial fibrillation in mitral valve surgery.

Science.gov (United States)

Graffigna, Angelo; Branzoli, Stefano; Sinelli, Stefano; Vigano, Mario

2009-01-01

The renewed interest in surgical techniques for atrial fibrillation (AF) limited to the left atrium has risen the importance of the original technique of left atrial isolation by means of surgical incision. Transmurality of lesions and cost containment are strong elements to be appreciated in this technique.

Effect of atrial preference pacing on reducing long-term burden of atrial fibrillation:a clinical study

International Nuclear Information System (INIS)

Xu Jianfeng; Chen Yueguang; Su Yangang; Zhang Dadong

2010-01-01

Objective: To evaluate the clinical effect of atrial preference pacing (APP) on the prevention of paroxysmal atrial fibrillation. Methods: Based on the type of implanted pacemaker, 46 patients with sick sinus syndrome and paroxysmal atrial fibrillation were divided into two groups. Dual-chamber pacemaker equipped with APP function was implanted in patients of group APP (n=21), while conventional dual-chamber pacemaker was implanted in patients of control group (n=25). The patients were followed up for six months, the maximum P wave duration (Pmax), the P wave dispersion (Pd), the structure of heart chambers, the data of automatic mode switch (AMS) and the total burden of atrial fibrillation were estimated,and the results were statistically analyzed and compared between two groups. Results: The basic clinical characteristics of two groups were comparable. After six months pacing, the difference in Pmax between two groups was of no significance (115.0 ± 10.1 ms vs 122.0 ± 11.0 ms, P > 0.05), while the increase of Pd in control group was more obvious than that in group APP (32.7 ± 4.2 ms vs 20.1 ± 5.3 ms, P 0.05), and also no remarkable difference in the left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) could be found (P > 0.05). Moreover, no significant difference existed between two groups (P > 0.05). After six months pacing,in group APP the frequencies of AMS decreased more sharply (145 ± 37 times vs 327 ± 13 times, P < 0.05), the duration of AMS shortened more apparently (73 ± 15 hours vs 139 ± 28 hours, P < 0.05) and the total burden of atrial fibrillation was alleviated more obviously (13 ± 5% vs 28 ± 6%, P < 0.05) when compared to those in control group. Conclusion: Atrial preference pacing can coordinate the anisotropy of double atrial depolarization, reduce the frequencies of long-term paroxysmal atrial fibrillation, shorten the duration of atrial fibrillation

Clinically oriented device programming in bradycardia patients: part 1 (sinus node disease). Proposals from AIAC (Italian Association of Arrhythmology and Cardiac Pacing).

Science.gov (United States)

Ziacchi, Matteo; Palmisano, Pietro; Biffi, Mauro; Ricci, Renato P; Landolina, Maurizio; Zoni-Berisso, Massimo; Occhetta, Eraldo; Maglia, Giampiero; Botto, Gianluca; Padeletti, Luigi; Boriani, Giuseppe

2018-04-01

: Modern pacemakers have an increasing number of programable parameters and specific algorithms designed to optimize pacing therapy in relation to the individual characteristics of patients. When choosing the most appropriate pacemaker type and programing, the following variables must be taken into account: the type of bradyarrhythmia at the time of pacemaker implantation; the cardiac chamber requiring pacing, and the percentage of pacing actually needed to correct the rhythm disorder; the possible association of multiple rhythm disturbances and conduction diseases; the evolution of conduction disorders during follow-up. The goals of device programing are to preserve or restore the heart rate response to metabolic and hemodynamic demands; to maintain physiological conduction; to maximize device longevity; to detect, prevent, and treat atrial arrhythmia. In patients with sinus node disease, the optimal pacing mode is DDDR. Based on all the available evidence, in this setting, we consider appropriate the activation of the following algorithms: rate responsive function in patients with chronotropic incompetence; algorithms to maximize intrinsic atrioventricular conduction in the absence of atrioventricular blocks; mode-switch algorithms; algorithms for autoadaptive management of the atrial pacing output; algorithms for the prevention and treatment of atrial tachyarrhythmias in the subgroup of patients with atrial tachyarrhythmias/atrial fibrillation. The purpose of this two-part consensus document is to provide specific suggestions (based on an extensive literature review) on appropriate pacemaker setting in relation to patients' clinical features.

Sino-Danish Brain Circulation

DEFF Research Database (Denmark)

Bertelsen, Rasmus Gjedssø; Du, Xiangyun; Søndergaard, Morten Karnøe

2014-01-01

China is faced with urgent needs to develop an economically and environmentally sustainable economy based on innovation and knowledge. Brain circulation and research and business investments from the outside are central for this development. Sino-American brain circulation and research...... and investment by overseas researchers and entrepreneurs are well described. In that case, the US is the center of global R&D and S&T. However, the brain circulation and research and investments between a small open Scandinavian economy, such as Denmark, and the huge developing economy of China are not well...... understood. In this case, Denmark is very highly developed, but a satellite in the global R&D and S&T system. With time and the growth of China as a R&D and S&T power house, both Denmark and China will benefit from brain circulation between them. Such brain circulation is likely to play a key role in flows...

Artificial atrial fibrillation in the dog. An artifact?

NARCIS (Netherlands)

Strackee, J.; Hoelen, A.J.; Zimmerman, A.N.E.; Meijler, F.L.

R-R interval sequences during artificial atrial fibrillation in dogs were studied in the same way as in patients in a previous study and compared with results obtained in dogs with spontaneous atrial fibrillation. Artificial atrial fibrillation was effected by right atrial stimulation in three

Left Atrial Linear Ablation of Paroxysmal Atrial Fibrillation Guided by Three-dimensional Electroanatomical System

DEFF Research Database (Denmark)

Zhang, Dai-Fu; Li, Ying; Qi, Wei-Gang

2005-01-01

Objective To investigate the safety and efficacy of Left atrial linear ablation of paroxysmal atrial fibrillation guided by three-dimensional electroanatomical system. Methods 29 patients with paroxysmal atrial fibrillation in this study. A nonfluoroscopic mapping system was used to generate a 3D...... electroanatomic LA mapping, and all pulmonary vein ostia were marked under the help of pulmonary veins angiography on the 3D map. Radiofrequency (RF) energy was delivered to create continuous linear lesions encircling the pulmonary veins, it was delivered with a target temperature of 43¿, a maximal power limit...

Left atrial appendage occlusion

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Ahmad Mirdamadi

2013-01-01

Full Text Available Left atrial appendage (LAA occlusion is a treatment strategy to prevent blood clot formation in atrial appendage. Although, LAA occlusion usually was done by catheter-based techniques, especially percutaneous trans-luminal mitral commissurotomy (PTMC, it can be done during closed and open mitral valve commissurotomy (CMVC, OMVC and mitral valve replacement (MVR too. Nowadays, PTMC is performed as an optimal management of severe mitral stenosis (MS and many patients currently are treated by PTMC instead of previous surgical methods. One of the most important contraindications of PTMC is presence of clot in LAA. So, each patient who suffers of severe MS is evaluated by Trans-Esophageal Echocardiogram to rule out thrombus in LAA before PTMC. At open heart surgery, replacement of the mitral valve was performed for 49-year-old woman. Also, left atrial appendage occlusion was done during surgery. Immediately after surgery, echocardiography demonstrates an echo imitated the presence of a thrombus in left atrial appendage area, although there was not any evidence of thrombus in pre-pump TEE. We can conclude from this case report that when we suspect of thrombus of left atrial, we should obtain exact history of previous surgery of mitral valve to avoid misdiagnosis clotted LAA, instead of obliterated LAA. Consequently, it can prevent additional evaluations and treatments such as oral anticoagulation and exclusion or postponing surgeries including PTMC.

Process ambiguities in Sino-Danish Business Negotiations

DEFF Research Database (Denmark)

Kumar, Rajesh; Worm, Verner

2004-01-01

. These ambiguities stem from differences in negotiation scripts across Danish and Chinese cultures. The essential argument being advanced here is that it is the effective and/or the ineffective management of process ambiguities that shapes the evolution of the negotiating dynamic between the Danish and the Chinese...... businesspeople. An inductive model of sino-Danish negotiations is developed that is based on 24 interviews conducted with Danish expatriate managers in China and 4 interviews with Chinese working in Danish companies. Implications for research and practice are discussed...

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

Prolonged postoperative desaturation in a child with Down syndrome and atrial septal defect

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Renu Sinha

2011-01-01

Full Text Available We report prolonged desaturation in a child with Down syndrome (DS and atrial septal defect due to undiagnosed interstitial lung disease. An 18-month-old child with DS was scheduled for bilateral lens aspiration for cataract. The child had atrial septal defect and hypothyroidism. He also had delayed milestones and hypotonia with episodes of recurrent respiratory tract infection necessitating repeated hospitalization. Preoperative evaluation was unremarkable. General anaesthesia and controlled ventilation using proseal laryngeal mask airway was instituted. He had uneventful intraoperative period. In the postoperative period, the child had desaturation 1 hour after surgery on discontinuation of oxygen supplementation by face mask, which improved with oxygen therapy. Supplemental oxygen via face mask was continued and weaned off over several days. On further evaluation, the child was diagnosed as having interstitial lung disease. He improved and discharged from the hospital 15 days after the surgery with room air saturation of 90%.

Risk of atrial fibrillation in diabetes mellitus

DEFF Research Database (Denmark)

Pallisgaard, Jannik L; Schjerning, Anne-Marie; Lindhardt, Tommi B

2016-01-01

AIM: Diabetes has been associated with atrial fibrillation but the current evidence is conflicting. In particular knowledge regarding young diabetes patients and the risk of developing atrial fibrillation is sparse. The aim of our study was to investigate the risk of atrial fibrillation in patients...... with diabetes compared to the background population in Denmark. METHODS AND RESULTS: Through Danish nationwide registries we included persons above 18 years of age and without prior atrial fibrillation and/or diabetes from 1996 to 2012. The study cohort was divided into a background population without diabetes...... and a diabetes group. The absolute risk of developing atrial fibrillation was calculated and Poisson regression models adjusted for sex, age and comorbidities were used to calculate incidence rate ratios of atrial fibrillation. The total study cohort included 5,081,087 persons, 4,827,713 (95%) in the background...

Personalized management of atrial fibrillation

DEFF Research Database (Denmark)

Kirchhof, Paulus; Breithardt, Günter; Aliot, Etienne

2013-01-01

The management of atrial fibrillation (AF) has seen marked changes in past years, with the introduction of new oral anticoagulants, new antiarrhythmic drugs, and the emergence of catheter ablation as a common intervention for rhythm control. Furthermore, new technologies enhance our ability......, and hospitalizations. During the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association (AFNET/EHRA) consensus conference, we identified the following opportunities to personalize management of AF in a better manner with a view to improve outcomes by integrating atrial morphology and damage...

Increased susceptibility to atrial fibrillation secondary to atrial fibrosis in transgenic goats expressing transforming growth factor - B1

Science.gov (United States)

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in people with significant morbidity and mortality. There is a strong association between atrial fibrosis and AF. Transforming growth factor B1 (TGF-B1) is an essential mediator of atrial fibrosis in animal models and human pat...

Effect of left ventricular diastolic dysfunction on left atrial appendage function and thrombotic potential in nonvalvular atrial fibrillation.

Science.gov (United States)

Demirçelik, Muhammed Bora; Çetin, Mustafa; Çiçekcioğlu, Hülya; Uçar, Özgül; Duran, Mustafa

2014-05-01

We aimed to investigate effects of left ventricular diastolic dysfunction on left atrial appendage functions, spontaneous echo contrast and thrombus formation in patients with nonvalvular atrial fibrillation. In 58 patients with chronic nonvalvular atrial fibrilation and preserved left ventricular systolic function, left atrial appendage functions, left atrial spontaneous echo contrast grading and left ventricular diastolic functions were evaluated using transthoracic and transoesophageal echocardiogram. Patients divided in two groups: Group D (n=30): Patients with diastolic dysfunction, Group N (n=28): Patients without diastolic dysfunction. Categorical variables in two groups were evaluated with Pearson's chi-square or Fisher's exact test. The significance of the lineer correlation between the degree of spontaneous echo contrast (SEC) and clinical measurements was evaluated with Spearman's correlation analysis. Peak pulmonary vein D velocity of the Group D was significantly higher than the Group N (p=0.006). However, left atrial appendage emptying velocity, left atrial appendage lateral wall velocity, peak pulmonary vein S, pulmonary vein S/D ratio were found to be significantly lower in Group D (p=0.028, patrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities respectively (r=-0.438, r=-0.328, r=-0.233, r=-0.447). Left atrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities were significantly lower in SEC 2-3-4 than SEC 1 (p=0.003, p=0.029, patrial fibrillation and preserved left ventricular ejection fraction, left atrial appendage functions are decreased in patients with left ventricular diastolic dysfunction. Left ventricular diastolic dysfunction may constitute a potential risk for formation of thrombus and stroke.

Priority targets for environmental research in the Sinos River basin

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FR. Spilki

Full Text Available The Sinos River Basin is often mentioned as a highly degraded watershed. A series of impacts on water quality, soil and air has been reported in this environment on a recurring basis over the years. This situation of environmental degradation has its origins in a process of huge economic development uncoupled from environmental conservation concerns. The intense consequent urbanization observed for the municipalities within the watershed was not preceded by urban planning proper zoning. The time has arrived for initiatives in scientific research in the Sinos River basin that are applicable to a more efficient and integrated management and recovery of the basin. In this article, a set of targets for research is suggested which the authors consider as the main priorities for the next few years, aiming for better knowledge and better management of the watershed. Some are still in course, while others have to be initiated as soon as possible.

[Recurrent right atrial thrombus in a patient with atrial fibrillation and heart failure].

Science.gov (United States)

Elikowski, Waldemar; Wróblewski, Dariusz; Małek-Elikowska, Małgorzata; Mazurek, Andrzej; Foremska-Iciek, Joanna; Łazowski, Stanisław

2015-11-01

Atrial fibrillation and heart failure are factors predisposing to locally formed intracardiac thrombosis, which is usually localized in left-sided chambers. A case report. The authors present a case of a 50-year-old male with permanent atrial fibrillation and dilated cardiomyopathy in whom recurrent right atrial thrombus was observed. Initially, the lesion was detected in echocardiography while he was hospitalized due to extensive right-sided pneumonia. The thrombus was successfully treated with heparin, followed by warfarin. Even though the patient continued warfarin use properly, there was recurrence of the thrombus two years later during a new episode of heart failure exacerbation. Because the thrombus was resistant to intensified anticoagulation, cardiac surgery was needed. A large (30 x 25 mm) pedunculated thrombus, as well as two smaller ones (each of 10 x 10 mm) attached closely to the atrial wall and previously not detected either by echocardiography or by magnetic resonance imaging, were excited. A partially organized pattern of the thrombi in histological examination can explain lack of anticoagulation effectiveness. © 2015 MEDPRESS.

Left atrial size and function as predictors of new-onset of atrial fibrillation in patients with asymptomatic aortic stenosis

DEFF Research Database (Denmark)

Bang, Casper Niels Furbo; Dalsgaard, Morten; Greve, Anders

2013-01-01

Left atrial (LA) size and function change with chronically increased left ventricular (LV) filling pressures. It remains unclear whether these variations in LA parameters can predict new-onset atrial fibrillation (AF) in asymptomatic patients with aortic stenosis (AS).......Left atrial (LA) size and function change with chronically increased left ventricular (LV) filling pressures. It remains unclear whether these variations in LA parameters can predict new-onset atrial fibrillation (AF) in asymptomatic patients with aortic stenosis (AS)....

Spectral of electrocardiographic RR intervals to indicate atrial fibrillation

Science.gov (United States)

Nuryani, Nuryani; Satrio Nugroho, Anto

2017-11-01

Atrial fibrillation is a serious heart diseases, which is associated on the risk of death, and thus an early detection of atrial fibrillation is necessary. We have investigated spectral pattern of electrocardiogram in relation to atrial fibrillation. The utilized feature of electrocardiogram is RR interval. RR interval is the time interval between a two-consecutive R peaks. A series of RR intervals in a time segment is converted to a signal with a frequency domain. The frequency components are investigated to find the components which significantly associate to atrial fibrillation. A segment is defined as atrial fibrillation or normal segments by considering a defined number of atrial fibrillation RR in the segment. Using clinical data of 23 patients with atrial fibrillation, we find that the frequency components could be used to indicate atrial fibrillation.

Hemodynamic forces regulate developmental patterning of atrial conduction.

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Michael C Bressan

Full Text Available Anomalous action potential conduction through the atrial chambers of the heart can lead to severe cardiac arrhythmia. To date, however, little is known regarding the mechanisms that pattern proper atrial conduction during development. Here we demonstrate that atrial muscle functionally diversifies into at least two heterogeneous subtypes, thin-walled myocardium and rapidly conducting muscle bundles, during a developmental window just following cardiac looping. During this process, atrial muscle bundles become enriched for the fast conduction markers Cx40 and Nav1.5, similar to the precursors of the fast conduction Purkinje fiber network located within the trabeculae of the ventricles. In contrast to the ventricular trabeculae, however, atrial muscle bundles display an increased proliferation rate when compared to the surrounding myocardium. Interestingly, mechanical loading of the embryonic atrial muscle resulted in an induction of Cx40, Nav1.5 and the cell cycle marker Cyclin D1, while decreasing atrial pressure via in vivo ligation of the vitelline blood vessels results in decreased atrial conduction velocity. Taken together, these data establish a novel model for atrial conduction patterning, whereby hemodynamic stretch coordinately induces proliferation and fast conduction marker expression, which in turn promotes the formation of large diameter muscle bundles to serve as preferential routes of conduction.

Tratamento cirúrgico da fibrilação atrial crônica com eletrocautério convencional em cirurgia valvar mitral Surgical treatment of chronic atrial fibrillation with conventional electrocautery in mitral valve surgery

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Jandir Ferreira Gomes Júnior

2008-09-01

age of the patients was 59 years, and 60.8% were female. The left atrium mean diameter was 50.3 ± 5.09 mm and the left ventricular ejection fraction was 53.6 ± 11.03%. RESULTS: The mean time of extracorporeal circulation was 52.5 ± 13.3 min; aortic clamping, 35.6 ± 12.9 min; atrial ablation, 3.05 ± 0.16 min. All the patients were free of atrial fibrillation after the procedure; on hospital discharge, 69.5%; at 6 months, 91.3%; at 12 months, 76.4%; at 18 months, and at 24 months, 68.4%. At 12 months, left atrium mean diameter was 42.1 ± 3.5 mm; left ventricular ejection fraction was 59.2 ± 3.48%; In addition, left atrial contraction was present in 68.8% of the patients. CONCLUSION: The surgical treatment of the atrial fibrillation with electrocautery in mitral valve surgery was capable to determine the reversion of this arrhythmia in a significant number of patients during short- and middle-term clinical follow-up without mortality and fewer complications.

A Study of Sino-Russian Energy Cooperation from the Perspective of Theories of International Relations

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Chaoyue Yang

2013-12-01

Full Text Available Energy cooperation is an important component in the Sino-Russia relationship. After more than a decade of efforts, China and Russia have made great progress in their cooperation in the area of oil and natural gas, which has not only promoted the economic developments in both countries, but also expanded their common interests to a large extent, resulting in a tremendous improvement of the two countries’ international strategies towards each other. Nevertheless, constrained and influenced by the evolution of contemporary international politics and economies, the Sino-Russia energy cooperation is facing some problems and barriers. Therefore, the aim of this article is to analyze the multiple elements affecting the Sino-Russia energy cooperation through the prism of Neo-realism, Neo-liberalism and Social Constructivism, hence a clear account of the opportunities and challenges that constitute this cooperation will be gained.

Effects of Persistent Atrial Fibrillation-Induced Electrical Remodeling on Atrial Electro-Mechanics - Insights from a 3D Model of the Human Atria.

Science.gov (United States)

Adeniran, Ismail; MacIver, David H; Garratt, Clifford J; Ye, Jianqiao; Hancox, Jules C; Zhang, Henggui

2015-01-01

Atrial stunning, a loss of atrial mechanical contraction, can occur following a successful cardioversion. It is hypothesized that persistent atrial fibrillation-induced electrical remodeling (AFER) on atrial electrophysiology may be responsible for such impaired atrial mechanics. This simulation study aimed to investigate the effects of AFER on atrial electro-mechanics. A 3D electromechanical model of the human atria was developed to investigate the effects of AFER on atrial electro-mechanics. Simulations were carried out in 3 conditions for 4 states: (i) the control condition, representing the normal tissue (state 1) and the tissue 2-3 months after cardioversion (state 2) when the atrial tissue recovers its electrophysiological properties after completion of reverse electrophysiological remodelling; (ii) AFER-SR condition for AF-remodeled tissue with normal sinus rhythm (SR) (state 3); and (iii) AFER-AF condition for AF-remodeled tissue with re-entrant excitation waves (state 4). Our results indicate that at the cellular level, AFER (states 3 & 4) abbreviated action potentials and reduced the Ca2+ content in the sarcoplasmic reticulum, resulting in a reduced amplitude of the intracellular Ca2+ transient leading to decreased cell active force and cell shortening as compared to the control condition (states 1 & 2). Consequently at the whole organ level, atrial contraction in AFER-SR condition (state 3) was dramatically reduced. In the AFER-AF condition (state 4) atrial contraction was almost abolished. This study provides novel insights into understanding atrial electro-mechanics illustrating that AFER impairs atrial contraction due to reduced intracellular Ca2+ transients.

Posibilities of cardiac pacemaker use in paroxsysmal atrial fibrilation

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Borut Kamenik

2005-12-01

Full Text Available Background: Prevention of atrial fibrillation is a big therapeutic challenge because of all known negative consequences of this the most frequent cardiac arrhythmia. Numerous of clinical studies showed bad control or ineffectiveness of antiarhythmic drugs. Nonfarmakological therapies like surgical treatment, radiofrequency ablation and atrial pacing are being tested. Effectiveness of atrial pacing in prevention of paroxysmal artial fibrillation has been documented in numerous prospective studies and is effective for a long time interval, but only for patients with bradicardic underlying cardiac rhythm. In Normocardic rhythm or normal AV conduction the effective Atrial fibrillation prevention was not proven. The mechanism of action is based on premature atrial complex suppression, reduction of dispersion of refractoriness after short-long cycles and reduction of interatrial conduction delay. The atrial stimulation site or multi-site atrial pacing could be effective in AF prevention when interatrial conduction delay is present; otherwise the difference is not significant.Conclusions: In bradicardic patient who has frequent paroxysms of atrial fibrillation, regardless if bradycardia is due to ineffective antiarrhythmic drug treathement, implantation of DDDR pacemaker with atrial prevention algorhythm is indicated. If the P-wave duration is >120 milliseconds multi-site atrial pacing or septal atrial pacing should be considered. Pacemaker diagnostic tools could be used for adequate start of anticoagulant therapy and control of effectiveness of anthyarhythmic drug therapy.

Sino-US cooperation in water saving technologies: essential international problems

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The United States and China share many agricultural problems, but one of great importance is the need to produce more crop yield in the face of water scarcity. Common recognition of this problem led to the development of a joint Sino-US Water Saving Technologies Flagship project within the larger US...

EXAMINATION OF ELECTROPHYSIOLOGICAL PARAMETERS OF THE ATRIUMS IN PATIENTS WITH LONG-TERM PERSISTENT FORM OF ATRIAL FIBRILLATION AND VALVULAR HEART DISEASE

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A. A. Kulikov

2017-01-01

Full Text Available The study objective is to examine electrophysiological parameters of atrial myocardium, characteristics of atrioventricular conduction, and potential factors affecting recurrent atrial fibrillation (AF in patients with persistent and long-term persistent forms of AF prior to the Labirynth IIIB surgery with single-step correction of valvular heart disease.Materials and methods. The study included 100 adults (48 men, 52 women with persistent and long-term persistent forms of AF and different valvular heart diseases. Mean patient age was 59 years. Mean AF duration was 4 years. All patients were prescribed antiarrhythmic therapy but it proved ineffective. In 15 % of patients, restoration of the sinus rhythm was attempted through electrical cardioversion but long-term control of the sinus rhythm wasn’t achieved. All patients were diagnosed with organic pathology of the mitral valve. Also, in 80 % of patients, relative insufficiency of the tricuspid valve was detected. Chronic heart failure functional class per NYHA was III. Size of the left atrium was 5 cm, mean left ventricular ejection fraction was 61 %. All patients underwent electrical cardioversion. After successful restoration of the sinus rhythm, endocardial electrophysiology study (EES of the heart was performed. Then, correction of valvular pathologies and the Labyrinth IIIB surgery were performed. Results. Examination of refractoriness of different parts of the atriums has shown that effective refractory period (ERP of the atrioventricular node was minimal compared to other parts of the atriums. Maximal ERP duration was observed in the upper part of the right atrium. Therefore, in patients with long history of AF, heterogeneity of atrial myocardium ERP duration is observed. In 17 % of patients, atrial vulnerability was detected. The area of atrial vulnerability was always associated with ERP. Its duration in patients with atrial vulnerability was significantly higher.Conclusion. Long

Recurrent atrial myxoma.

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Macarie, C; Stoica, E; Chioncel, O; Carp, A; Gherghiceanu, D; Stiru, O; Zarma, L; Herlea, V

2004-01-01

We have chosen this case of sporadic atrial myxoma for our presentation because it had a particular evolution, with recurrence at 8 years after surgical excision (echocardiography was performed every year) and a particular diagnostic means - at echocardiographic follow-up, the patient being asymptomatic. This presentation, together with a review of literature included in the article, emphasizes the importance of a careful postoperative follow-up of the patients and the existence of some particular aspects of the evolution and symptomatology of recurrent atrial myxoma.

Association Between Left Atrial Compression And Atrial Fibrillation: A Case Presentation And A Short Review Of Literature.

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Ahmed, Niloy; Carlos, Morales-Mangual; Moshe, Gunsburg; Yitzhak, Rosen

2016-01-01

This case report describes a patient who developed palpitations and chest pain and was found to be in atrial fibrillation, which was likely due to the presence of an extra-cardiac mass. This was compressing the left atrium. The mass was related to small cell carcinoma, which decreased significantly in size after chemotherapy. Resolution of the atrial fibrillation correlated temporally with reduction in the size of the mass and alleviation of the left atrial compression.

Genetic basis of atrial fibrillation

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Oscar Campuzano

2016-12-01

Full Text Available Atrial fibrillation is the most common sustained arrhythmia and remains as one of main challenges in current clinical practice. The disease may be induced secondary to other diseases such as hypertension, valvular heart disease, and heart failure, conferring an increased risk of stroke and sudden death. Epidemiological studies have provided evidence that genetic factors play an important role and up to 30% of clinically diagnosed patients may have a family history of atrial fibrillation. To date, several rare variants have been identified in a wide range of genes associated with ionic channels, calcium handling protein, fibrosis, conduction and inflammation. Important advances in clinical, genetic and molecular basis have been performed over the last decade, improving diagnosis and treatment. However, the genetics of atrial fibrillation is complex and pathophysiological data remains still unraveling. A better understanding of the genetic basis will induce accurate risk stratification and personalized clinical treatment. In this review, we have focused on current genetics basis of atrial fibrillation.

Effects of Persistent Atrial Fibrillation-Induced Electrical Remodeling on Atrial Electro-Mechanics – Insights from a 3D Model of the Human Atria

Science.gov (United States)

Adeniran, Ismail; MacIver, David H.; Garratt, Clifford J.; Ye, Jianqiao; Hancox, Jules C.; Zhang, Henggui

2015-01-01

Aims Atrial stunning, a loss of atrial mechanical contraction, can occur following a successful cardioversion. It is hypothesized that persistent atrial fibrillation-induced electrical remodeling (AFER) on atrial electrophysiology may be responsible for such impaired atrial mechanics. This simulation study aimed to investigate the effects of AFER on atrial electro-mechanics. Methods and Results A 3D electromechanical model of the human atria was developed to investigate the effects of AFER on atrial electro-mechanics. Simulations were carried out in 3 conditions for 4 states: (i) the control condition, representing the normal tissue (state 1) and the tissue 2–3 months after cardioversion (state 2) when the atrial tissue recovers its electrophysiological properties after completion of reverse electrophysiological remodelling; (ii) AFER-SR condition for AF-remodeled tissue with normal sinus rhythm (SR) (state 3); and (iii) AFER-AF condition for AF-remodeled tissue with re-entrant excitation waves (state 4). Our results indicate that at the cellular level, AFER (states 3 & 4) abbreviated action potentials and reduced the Ca2+ content in the sarcoplasmic reticulum, resulting in a reduced amplitude of the intracellular Ca2+ transient leading to decreased cell active force and cell shortening as compared to the control condition (states 1 & 2). Consequently at the whole organ level, atrial contraction in AFER-SR condition (state 3) was dramatically reduced. In the AFER-AF condition (state 4) atrial contraction was almost abolished. Conclusions This study provides novel insights into understanding atrial electro-mechanics illustrating that AFER impairs atrial contraction due to reduced intracellular Ca2+ transients. PMID:26606047

Effects of Acetylcholine and Noradrenalin on Action Potentials of Isolated Rabbit Sinoatrial and Atrial Myocytes

Science.gov (United States)

Verkerk, Arie O.; Geuzebroek, Guillaume S. C.; Veldkamp, Marieke W.; Wilders, Ronald

2012-01-01

The autonomic nervous system controls heart rate and contractility through sympathetic and parasympathetic inputs to the cardiac tissue, with acetylcholine (ACh) and noradrenalin (NA) as the chemical transmitters. In recent years, it has become clear that specific Regulators of G protein Signaling proteins (RGS proteins) suppress muscarinic sensitivity and parasympathetic tone, identifying RGS proteins as intriguing potential therapeutic targets. In the present study, we have identified the effects of 1 μM ACh and 1 μM NA on the intrinsic action potentials of sinoatrial (SA) nodal and atrial myocytes. Single cells were enzymatically isolated from the SA node or from the left atrium of rabbit hearts. Action potentials were recorded using the amphotericin-perforated patch-clamp technique in the absence and presence of ACh, NA, or a combination of both. In SA nodal myocytes, ACh increased cycle length and decreased diastolic depolarization rate, whereas NA decreased cycle length and increased diastolic depolarization rate. Both ACh and NA increased maximum upstroke velocity. Furthermore, ACh hyperpolarized the maximum diastolic potential. In atrial myocytes stimulated at 2 Hz, both ACh and NA hyperpolarized the maximum diastolic potential, increased the action potential amplitude, and increased the maximum upstroke velocity. Action potential duration at 50 and 90% repolarization was decreased by ACh, but increased by NA. The effects of both ACh and NA on action potential duration showed a dose dependence in the range of 1–1000 nM, while a clear-cut frequency dependence in the range of 1–4 Hz was absent. Intermediate results were obtained in the combined presence of ACh and NA in both SA nodal and atrial myocytes. Our data uncover the extent to which SA nodal and atrial action potentials are intrinsically dependent on ACh, NA, or a combination of both and may thus guide further experiments with RGS proteins. PMID:22754533

Thyrotoxic atrial fibrillation.

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Parmar, Malvinder S

2005-01-04

Atrial fibrillation is the most common cardiac complication of hyperthyroidism and occurs in 15% of patients with hyperthyroidism. It is associated with a higher risk of thromboembolism that often involves the central nervous system. Oral anticoagulation is important in the majority of these patients to prevent thromboembolic complications. These patients require adjustment in the dose of various rate-controlling agents because of increased clearance associated with hyperthyroidism and a decrease in warfarin dosage because of increased clearance of vitamin K-dependent clotting factors. The management of thyrotoxic atrial fibrillation is summarized in this clinical review.

The absent father of Sino-French cinema: Contemporary Taiwanese cinema and 1950s French auteurs

OpenAIRE

Bloom, ME

2014-01-01

© 2014 Taylor & Francis. In contemporary Sino-French cinema, father characters who are dead, long lost or geographically distant leave gaping holes in the lives of the offspring left behind. The absent fathers in Sino-French films by Taiwanese auteurs Cheng Yu-chieh, Hou Hsiao-hsien and Tsai Ming-liang serve as metaphors for French auteurs. French New Wave films constitute the majority of the intertexts; however, early 1950s French cinema and even late nineteenth-century painting reflect th...

Left atrial size in patients with cryptogenic stroke as a predictor of occurrence of atrial fibrillation

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Antonio Cruz Culebras

2017-04-01

Full Text Available Objective: To determine whether the left atrial size can predict the development of atrial fibrillation (AF in patients with embolic stroke of undetermined source (ESUS. Methods: Patients with ischemic stroke were included prospectively (January 2015-July 2015 when ESUS was suspected. Clinical and cardiac imaging data were recorded. Patients with cardiac failure were excluded. Results: a total of 55 patients were included. Medium age was 71 years. The proportion of patients who developed AF during the follow-up (1 year was 23, 63%. 10 % of patients did not have any vascular risk factor. Basal ECG was normal in 98% of cases. The left atrial size volume was 36, 08 ml in patients who developed AF and 27, 14 ml in patients who did not. Conclusions: In patients with ESUS, left atrial size dimensions do not predict the occurrence of AF.

RR-Interval variance of electrocardiogram for atrial fibrillation detection

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Nuryani, N.; Solikhah, M.; Nugoho, A. S.; Afdala, A.; Anzihory, E.

2016-11-01

Atrial fibrillation is a serious heart problem originated from the upper chamber of the heart. The common indication of atrial fibrillation is irregularity of R peak-to-R-peak time interval, which is shortly called RR interval. The irregularity could be represented using variance or spread of RR interval. This article presents a system to detect atrial fibrillation using variances. Using clinical data of patients with atrial fibrillation attack, it is shown that the variance of electrocardiographic RR interval are higher during atrial fibrillation, compared to the normal one. Utilizing a simple detection technique and variances of RR intervals, we find a good performance of atrial fibrillation detection.

Sinos River Hydrographic Basin: urban occupation, industrialization and environmental memory

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M. F. Nunes

Full Text Available This article presents an analysis of the process of industrialization and urbanization of the Sinos Valley in Rio Grande do Sul state, Brazil, starting from the establishment of leather goods and footwear manufacturing in the region during the 19th century when tanneries and factories producing footwear and/or components for footwear began to appear, and with special attention to aspects related to the environmental impact on the Sinos river hydrographic basin. The article is based on both bibliographic and documentary research and also draws on biographical narratives of workers with links to the leather goods and footwear industry obtained using ethnographic method. It was found that contemporary environmental conflicts emerge from within a memory of work and an environmental memory in which the factories, the unplanned urbanization, and the utilization of water and other natural resources form a chain of significance. Significance that precludes any form of fragmented analysis that isolates any of these aspects from the others: the economic, socio-historic, cultural, political, or the environmental.

Sinos River Hydrographic Basin: urban occupation, industrialization and environmental memory.

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Nunes, M F; Figueiredo, J A S; Rocha, A L C

2015-12-01

This article presents an analysis of the process of industrialization and urbanization of the Sinos Valley in Rio Grande do Sul state, Brazil, starting from the establishment of leather goods and footwear manufacturing in the region during the 19th century when tanneries and factories producing footwear and/or components for footwear began to appear, and with special attention to aspects related to the environmental impact on the Sinos river hydrographic basin. The article is based on both bibliographic and documentary research and also draws on biographical narratives of workers with links to the leather goods and footwear industry obtained using ethnographic method. It was found that contemporary environmental conflicts emerge from within a memory of work and an environmental memory in which the factories, the unplanned urbanization, and the utilization of water and other natural resources form a chain of significance. Significance that precludes any form of fragmented analysis that isolates any of these aspects from the others: the economic, socio-historic, cultural, political, or the environmental.

Anesthetic management of Amplatzer atrial septal defect closure device embolization to right ventricular outflow tract

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S Das

2016-01-01

Full Text Available Percutaneous device closure of atrial septal defect (ASD is an alternative treatment to surgery with advantages of avoidance of surgery, short procedure time, early discharge from hospital, and lower rates of complications. However, percutaneous device closure is associated with infrequent life-threatening complications such as device embolization. We report a case device embolization of the ASD occlude device into right ventricular outflow tract resulting progressive hypoxia. The role of anesthesiologist as a team leader in managing such emergency is discussed.

Ventricular myocarditis coincides with atrial myocarditis in patients

NARCIS (Netherlands)

Begieneman, Mark P. V.; Emmens, Reindert W.; Rijvers, Liza; Kubat, Bela; Paulus, Walter J.; Vonk, Alexander B. A.; Rozendaal, Lawrence; Biesbroek, P. Stefan; Wouters, Diana; Zeerleder, Sacha; van Ham, Marieke; Heymans, Stephane; van Rossum, Albert C.; Niessen, Hans W. M.; Krijnen, Paul A. J.

2016-01-01

Atrial fibrillation (AF) is a common complication in myocarditis. Atrial inflammation has been suggested to play an important role in the pathophysiology of AF. However, little is known about the occurrence of atrial inflammation in myocarditis patients. Here, we analyzed inflammatory cell numbers

Duration of Diabetes Mellitus and Risk of Thromboembolism and Bleeding in Atrial Fibrillation: Nationwide Cohort Study.

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Overvad, Thure Filskov; Skjøth, Flemming; Lip, Gregory Y H; Lane, Deirdre A; Albertsen, Ida Ehlers; Rasmussen, Lars Hvilsted; Larsen, Torben Bjerregaard

2015-08-01

Guidelines advocate anticoagulant treatment to all patients with atrial fibrillation and concomitant diabetes mellitus. The potential refinement to thromboembolic risk stratification that may spring from subdividing diabetes mellitus is unexplored. The purpose was to investigate duration of diabetes mellitus as a predictor of thromboembolism and anticoagulant-related bleeding in patients with atrial fibrillation. Using nationwide Danish registries, we identified all patients discharged from hospital with an incident diagnosis of atrial fibrillation from 2000 to 2011. Hazard ratios with 95% confidence intervals for thromboembolism and bleeding according to years of diabetes mellitus duration in categories (0-4, 5-9, 10-14, and ≥15) and as a continuous variable using cubic splines were calculated by Cox regression. The study population comprised 137 222 patients with atrial fibrillation, of which 12.4% had diabetes mellitus. Compared with patients without diabetes mellitus and after adjustment for anticoagulant treatment and CHA2DS2-VASc components (congestive heart failure, hypertension, age, previous stroke, vascular disease, and sex), the risk of thromboembolism was lowest in the 0 to 4 years duration category (hazard ratio, 1.11; 95% confidence interval, 1.03-1.20), and highest in the longest duration category of ≥15 years (hazard ratio, 1.48; 95% confidence interval, 1.29-1.70). When analyzed as a continuous variable, duration of diabetes mellitus was associated with risk of thromboembolism in a dose-response-dependent manner, but not with a higher risk of bleeding during anticoagulant treatment. In patients with atrial fibrillation, longer duration of diabetes mellitus was associated with a higher risk of thromboembolism, but not with a higher risk of anticoagulant-related bleeding. Considering the critical balance between preventing thromboembolism and avoiding bleeding, longer duration of diabetes mellitus may favor initiation of anticoagulant therapy. �

Water quality assessment of the Sinos River – RS, Brazil

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C. Steffens

Full Text Available Worldwide environmental pollution is increasing at the same rate as social and economic development. This growth, however, is disorganized and leads to increased degradation of water resources. Water, which was once considered inexhaustible, has become the focus of environmental concerns because it is essential for life and for many production processes. This article describes monitoring of the water quality at three points along the Sinos River (RS, Brazil, one in each of the upper, middle and lower stretches. The points were sampled in 2013 and again in 2014. The water samples were analyzed to determine the following physical and chemical parameters plus genotoxicity to fish: metals (Cr, Fe, Al, chemical oxygen demand, biochemical oxygen demand, chlorides, conductivity, total suspended solids, total phosphorous, total and fecal coliforms, pH, dissolved oxygen, turbidity, total Kjeldahl nitrogen nitrate and ammoniacal nitrogen. Genotoxicity was tested by exposing individuals of the species Astyanax jacuhiensis to water samples and then comparing them with a control group exposed to water from the public water supply. The results confirmed the presence of substances with genotoxic potential at the sample points located in the middle and lower stretches of the river. The results for samples from the upper stretch, at P1, did not exhibit differences in relation to the control group. The physical and chemical analyses did not detect reductions in water quality in the lower stretch, as had been expected in view of the large volumes of domestic and industrial effluents discharged into this part of the river.

Persistent atrial fibrillation vs paroxysmal atrial fibrillation: differences in management.

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Margulescu, Andrei D; Mont, Lluis

2017-08-01

Atrial fibrillation (AF) is the most common human arrhythmia. AF is a progressive disease, initially being nonsustained and induced by trigger activity, and progressing towards persistent AF through alteration of the atrial myocardial substrate. Treatment of AF aims to decrease the risk of stroke and improve the quality of life, by preventing recurrences (rhythm control) or controlling the heart rate during AF (rate control). In the last 20 years, catheter-based and, less frequently, surgical and hybrid ablation techniques have proven more successful compared with drug therapy in achieving rhythm control in patients with AF. However, the efficiency of ablation techniques varies greatly, being highest in paroxysmal and lowest in long-term persistent AF. Areas covered: In this review, we discuss the fundamental differences between paroxysmal and persistent AF and the potential impact of those differences on patient management, emphasizing the available therapeutic strategies to achieve rhythm control. Expert commentary: Treatment to prevent AF recurrences is suboptimal, particularly in patients with persistent AF. Emerging technologies, such as documentation of atrial fibrosis using magnetic resonance imaging and documentation of electrical substrate using advanced electrocardiographic imaging techniques are likely to provide valuable insights about patient-specific tailoring of treatments.

Left atrial appendage occlusion for stroke prevention in atrial fibrillation in Europe

DEFF Research Database (Denmark)

Lip, Gregory Y.H.; Dagres, Nikolaos; Proclemer, Alessandro

2013-01-01

The purpose of this EP wire survey was to assess clinical practice in relation to the use of left atrial appendage occlusion (LAAO) devices for stroke prevention in atrial fibrillation (AF) among members of the European Heart Rhythm Association research network. The average number of performed LA...... are most often performed by interventional cardiologists. Experience varied widely, and this was reflected in the wide range of thromboembolic and procedural (tamponade, bleeding) complications reported by the respondents to this EP wire survey....

Treatment of refractory sino-nasal aspergillosis with posaconazole and terbinafine in 10 dogs.

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Stewart, J; Bianco, D

2017-09-01

To determine the safety and efficacy of posaconazole and terbinafine for the treatment of naturally occurring sino-nasal aspergillosis in dogs refractory to conventional topical and systemic treatment. Ten client-owned dogs with sino-nasal aspergillosis and not responsive to conventional treatments were prospectively enrolled to receive a dose of 5 mg/kg posaconazole orally every 12 hours for six months. All dogs were concurrently treated with doses of 30 mg/kg terbinafine orally every 12 hours and 5 mg/kg doxycycline orally every 12 hours for 6 to 18 months. All 10 enrolled dogs completed the study. The treatment response was defined as complete clinical remission (n=7) or partial clinical remission (n=3). Two dogs relapsed after cessation of combination therapy. All dogs lived more than one year after starting combination therapy and eight dogs are alive at the time of writing. No clinically relevant adverse reactions or increases in hepatic enzyme activity occurred during the combination therapy. The results of this study suggest that this combination therapy appears safe and well-tolerated for the treatment of refractory sino-nasal aspergillosis in dogs. Long-term survival is possible with prolonged treatment, but relapse is possible. Larger prospective studies are warranted to further evaluate these preliminary findings. © 2017 British Small Animal Veterinary Association.

Rising rates of hospital admissions for atrial fibrillation

DEFF Research Database (Denmark)

Friberg, Jens; Buch, Nina Pernille Gardshodn; Scharling, Henrik

2003-01-01

Atrial fibrillation is a common arrhythmia associated with excess morbidity and mortality. We studied temporal changes in hospital admission rates for atrial fibrillation using data from a prospective population-based cohort study spanning 2 decades (the Copenhagen City Heart Study).......Atrial fibrillation is a common arrhythmia associated with excess morbidity and mortality. We studied temporal changes in hospital admission rates for atrial fibrillation using data from a prospective population-based cohort study spanning 2 decades (the Copenhagen City Heart Study)....

Development and feasibility testing of the Pediatric Emergency Discharge Interaction Coding Scheme.

Science.gov (United States)

Curran, Janet A; Taylor, Alexandra; Chorney, Jill; Porter, Stephen; Murphy, Andrea; MacPhee, Shannon; Bishop, Andrea; Haworth, Rebecca

2017-08-01

Discharge communication is an important aspect of high-quality emergency care. This study addresses the gap in knowledge on how to describe discharge communication in a paediatric emergency department (ED). The objective of this feasibility study was to develop and test a coding scheme to characterize discharge communication between health-care providers (HCPs) and caregivers who visit the ED with their children. The Pediatric Emergency Discharge Interaction Coding Scheme (PEDICS) and coding manual were developed following a review of the literature and an iterative refinement process involving HCP observations, inter-rater assessments and team consensus. The coding scheme was pilot-tested through observations of HCPs across a range of shifts in one urban paediatric ED. Overall, 329 patient observations were carried out across 50 observational shifts. Inter-rater reliability was evaluated in 16% of the observations. The final version of the PEDICS contained 41 communication elements. Kappa scores were greater than .60 for the majority of communication elements. The most frequently observed communication elements were under the Introduction node and the least frequently observed were under the Social Concerns node. HCPs initiated the majority of the communication. Pediatric Emergency Discharge Interaction Coding Scheme addresses an important gap in the discharge communication literature. The tool is useful for mapping patterns of discharge communication between HCPs and caregivers. Results from our pilot test identified deficits in specific areas of discharge communication that could impact adherence to discharge instructions. The PEDICS would benefit from further testing with a different sample of HCPs. © 2017 The Authors. Health Expectations Published by John Wiley & Sons Ltd.

Biomarkers of Atrial Cardiopathy and Atrial Fibrillation Detection on Mobile Outpatient Continuous Telemetry After Embolic Stroke of Undetermined Source.

Science.gov (United States)

Sebasigari, Denise; Merkler, Alexander; Guo, Yang; Gialdini, Gino; Kummer, Benjamin; Hemendinger, Morgan; Song, Christopher; Chu, Antony; Cutting, Shawna; Silver, Brian; Elkind, Mitchell S V; Kamel, Hooman; Furie, Karen L; Yaghi, Shadi

2017-06-01

Biomarkers of atrial dysfunction or "cardiopathy" are associated with embolic stroke risk. However, it is unclear if this risk is mediated by undiagnosed paroxysmal atrial fibrillation or flutter (AF). We aim to determine whether atrial cardiopathy biomarkers predict AF on continuous heart-rhythm monitoring after embolic stroke of undetermined source (ESUS). This was a single-center retrospective study including all patients with ESUS undergoing 30 days of ambulatory heart-rhythm monitoring to look for AF between January 1, 2013 and December 31, 2015. We reviewed medical records for clinical, radiographic, and cardiac variables. The primary outcome was a new diagnosis of AF detected during heart-rhythm monitoring. The primary predictors were atrial biomarkers: left atrial diameter on echocardiography, P-wave terminal force in electrocardiogram (ECG) lead V1, and P wave - R wave (PR) interval on ECG. A multiple logistic regression model was used to assess the relationship between atrial biomarkers and AF detection. Among 196 eligible patients, 23 (11.7%) were diagnosed with AF. In unadjusted analyses, patients with AF were older (72.4 years versus 61.4 years, P atrial diameter (39.2 mm versus 35.7 mm, P = .03). In a multivariable model, the only predictor of AF was age ≥ 60 years (odds ratio, 3.0; 95% CI, 1.06-8.5; P = .04). Atrial biomarkers were weakly associated with AF after ESUS. This suggests that previously reported associations between these markers and stroke may reflect independent cardiac pathways leading to stroke. Prospective studies are needed to investigate these mechanisms. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

ATRIAL FLUTTER*

African Journals Online (AJOL)

1971-01-02

Jan 2, 1971 ... Athero- sclerotic cardiovascular disease was present in 23 patients, of whom 3 had ... primum defect, atrial flutter was precipitated by cardiac catheterization. ..... Heart J., 70, 505. UNDERSTANDING REACTIVE DEPRESSION*

ABO blood groups: A risk factor for left atrial and left atrial appendage thrombogenic milieu in patients with non-valvular atrial fibrillation.

Science.gov (United States)

Fu, Yuan; Li, Kuibao; Yang, Xinchun

2017-08-01

Previous studies have identified ABO blood groups as predictors of thromboembolic diseases. In patients with atrial fibrillation (AF), however, potential association between ABO blood groups and the risk of left atrial (LA) and/or left atrial appendage (LAA) thrombogenic milieu (TM) has not been established. This is a retrospective case-control study that included 125 consecutive patients with non-valvular atrial fibrillation (NVAF) plus TM, as evidenced by transesophageal echocardiography (TEE) during a period from1 January 2010 to 31 December 2016. The controls were selected randomly from 1072 NVAF without TM at a 1:2 ratio. Potential association between ABO blood groups and TM was analyzed using multivariate logistic regression analysis. The risk of TM was higher in patients with blood group A (33.6% vs. 20.2% in non-A blood groups, P=0.005). After adjusting for age, sex, oral anticoagulant use, AF type and duration, and relevant functional measures (e.g., NT-pro BNP level, left atrium diameter, and left ventricular ejection fraction), blood group A remained associated with an increased risk of TM (OR=2.99, 95% CI 1.4-6.388, P=0.005). Blood group A is an independent risk factor for TM in NVAF patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Combined percutaneous balloon mitral valvuloplasty and left atrial appendage occlusion device implantation for rheumatic mitral stenosis and atrial fibrillation

International Nuclear Information System (INIS)

Murdoch, Dale; McAulay, Laura; Walters, Darren L.

2014-01-01

Rheumatic heart disease is a common cause of cardiovascular morbidity and mortality worldwide, mostly in developing countries. Mitral stenosis and atrial fibrillation often coexist, related to both structural and inflammatory changes of the mitral valve and left atrium. Both predispose to left atrial thrombus formation, commonly involving the left atrial appendage. Thromboembolism can occur, with devastating consequences. We report the case of a 62 year old woman with rheumatic heart disease resulting in mitral stenosis and atrial fibrillation. Previous treatment with warfarin resulted in life-threatening gastrointestinal bleeding and she refused further anticoagulant therapy. A combined procedure was performed, including percutaneous balloon mitral valvuloplasty and left atrial appendage occlusion device implantation with the Atritech® Watchman® device. No thromboembolic or bleeding complications were encountered at one year follow-up. Long-term follow-up in a cohort of patients will be required to evaluate the safety and efficacy of this strategy

Combined percutaneous balloon mitral valvuloplasty and left atrial appendage occlusion device implantation for rheumatic mitral stenosis and atrial fibrillation

Energy Technology Data Exchange (ETDEWEB)

Murdoch, Dale, E-mail: dale_murdoch@health.qld.gov.au [The Prince Charles Hospital, Brisbane (Australia); The University of Queensland, Brisbane (Australia); McAulay, Laura [The Prince Charles Hospital, Brisbane (Australia); Walters, Darren L. [The Prince Charles Hospital, Brisbane (Australia); The University of Queensland, Brisbane (Australia)

2014-11-15

Rheumatic heart disease is a common cause of cardiovascular morbidity and mortality worldwide, mostly in developing countries. Mitral stenosis and atrial fibrillation often coexist, related to both structural and inflammatory changes of the mitral valve and left atrium. Both predispose to left atrial thrombus formation, commonly involving the left atrial appendage. Thromboembolism can occur, with devastating consequences. We report the case of a 62 year old woman with rheumatic heart disease resulting in mitral stenosis and atrial fibrillation. Previous treatment with warfarin resulted in life-threatening gastrointestinal bleeding and she refused further anticoagulant therapy. A combined procedure was performed, including percutaneous balloon mitral valvuloplasty and left atrial appendage occlusion device implantation with the Atritech® Watchman® device. No thromboembolic or bleeding complications were encountered at one year follow-up. Long-term follow-up in a cohort of patients will be required to evaluate the safety and efficacy of this strategy.

Assessment of right atrial function analysis

International Nuclear Information System (INIS)

Shohgase, Takashi; Miyamoto, Atsushi; Kanamori, Katsushi; Kobayashi, Takeshi; Yasuda, Hisakazu

1988-01-01

To assess the potential utility of right atrial function analysis in cardiac disease, reservoir function, pump function, and right atrial peak emptying rate (RAPER) were compared in 10 normal subjects, 32 patients with coronary artery disease, and 4 patients with primary pulmonary hypertension. Right atrial volume curves were obtained using cardiac radionuclide method with Kr-81m. In normal subjects, reservoir function index was 0.41+-0.05; pump function index was 0.25+-0.05. Both types of patients has decreased reservoir funcion and increased pump function. Pump function tended to decrease with an increase of right ventricular end-diastolic pressure. RAPER correlated well with right ventricular peak filling rate, probably reflecting right ventricular diastolic function. Analysis of right atrial function seemed to be of value in evaluating factors regulating right ventricular contraction and diastolic function, and cardiac output. (Namekawa, K)

Increased risk of sudden and non-sudden cardiovascular death in patients with atrial fibrillation/flutter following acute myocardial infarction

DEFF Research Database (Denmark)

Pedersen, Ole Dyg; Abildstrøm, Steen Z; Ottesen, Michael M

2005-01-01

AIMS: Atrial fibrillation (AF) is a common complication in patients with acute myocardial infarction and is associated with an increase in the risk of death. The excess mortality associated with AF complicating acute myocardial infarction has not been studied in detail. Observations indicate...... that AF facilitates induction of ventricular arrhythmias, which may increase the risk of sudden cardiovascular death (SCD). A close examination of the mode of death could potentially provide useful knowledge to guide further investigations and treatments. METHODS AND RESULTS: We analysed the relation...... between AF/atrial flutter (AFL) and modes of death in 5983 consecutive patients discharged alive after an acute myocardial infarction screened in the TRAndolapril Cardiac Evaluation registry. This cohort of patients with an enzyme-verified acute myocardial infarction was admitted to 27 centres in 1990...

Atrial natriuretic peptide (ANP)-granules: ultrastructure ...

African Journals Online (AJOL)

ANP) are present in the four regions of the atrial-auricular complex (two atria and two auricles). ANP-immunoreactivity was detected in all granules from the four regions. Ultrastructurally, atrial myocytes show the presence of very electron dense ...

HYPERTHYROIDISM AND ATRIAL FIBRILLATION

Directory of Open Access Journals (Sweden)

I. M. Marusenko

2017-01-01

Full Text Available Review on a problem of the development of atrial fibrillation in patients with thyrotoxicosis is presented. Thyrotoxicosis is one of the most frequent endocrine diseases, conceding only to a diabetes mellitus. The most frequent reasons of hyperthyroidism are Graves’ disease and functional thyroid autonomy. The authors give an analysis of data on the cardiac effects of thyrotoxicosis, features of heart remodeling under the influence of thyroid hyperfunction, prevalence of atrial fibrillation in thyrotoxicosis, depending on age, as well as the possibility of restoring sinus rhythm in the combination of these diseases. Particular attention is paid to the effect on the heart of subclinical thyrotoxicosis, which is defined as a dysfunction of the thyroid gland, characterized by low serum concentration of thyrotropin, normal values of free thyroxine and free triiodothyronine. Subclinical hyperthyroidism is also capable of causing heart remodeling and diastolic dysfunction.Prevalence of thyrotoxicosis in elderly people is higher in areas of iodine deficiency; it is relevant for our country due to the large territory of iodine deficiency. In elderly patients, the cardiac effects of thyrotoxicosis prevail in the clinical picture, that makes it difficult to diagnose endocrine disorders, and correction of thyrotoxicosis is critically important for the successful control of the heart rhythm. The article also discusses the problem of thyrotoxic cardiomyopathy, caused by the toxic effect of excess thyroid hormones: features of this heart disorder, factors affecting its formation, clinical significance and contribution to the development of rhythm disturbances. The greatest significance is the development of atrial fibrillation as a result of thyrotox-icosis in older patients who already have various cardiovascular diseases.Atrial fibrillation is the most frequent heart rhythm disorder in thyrotoxicosis. The main cause of arrhythmia in hyperthyroidism is the

[Atrial fibrillation as consequence and cause of structural changes of atria].

Science.gov (United States)

Aparina, O P; Chikhireva, L N; Stukalova, O V; Mironova, N A; Kashtanova, S Iu; Ternovoĭ, S K; Golitsyn, S P

2014-01-01

Changes of atrial structure and function are the contributors of atrial fibrillation clinical course, complications and treatment effectiveness. Effects of inflammation and mechanical stretch on atrial structural remodeling leading to atrial fibrillation are reviewed in the article. Contemporary invasive and non-invasive methods of evaluation (including late gadolinium enhancement magnetic resonance imaging) of patients with atrial structural remodeling in atrial fibrillation are also described.

Embolic Risk in Atrial Fibrillation that Arises from Hyperthyroidism

Science.gov (United States)

Traube, Elie; Coplan, Neil L.

2011-01-01

Atrial fibrillation, the most common cardiac complication of hyperthyroidism, occurs in an estimated 10% to 25% of overtly hyperthyroid patients. The prevalence of atrial fibrillation increases with age in the general population and in thyrotoxic patients. Other risk factors for atrial fibrillation in thyrotoxic patients include male sex, ischemic or valvular heart disease, and congestive heart failure. The incidence of arterial embolism or stroke in thyrotoxic atrial fibrillation is less clear. There are many reports of arterial thromboembolism associated with hyperthyroidism, including cases of young adults without coexisting risk factors other than thyrotoxic atrial fibrillation. The use of anticoagulative agents to prevent thromboembolic sequelae of thyrotoxic atrial fibrillation is controversial: national organizations provide conflicting recommendations in their practice guidelines. Herein, we review the medical literature and examine the evidence behind the recommendations in order to determine the best approach to thromboembolic prophylaxis in patients who have atrial fibrillation that is associated with hyperthyroidism. PMID:21720457

Contemporary Antithrombotic Treatment in Patients with Non-valvular Atrial Fibrillation Undergoing Percutaneous Coronary Intervention: Rationale and Design of the Greek AntiPlatElet Atrial Fibrillation (GRAPE-AF) Registry.

Science.gov (United States)

Xanthopoulou, Ioanna; Dragona, Vasiliki-Maria; Davlouros, Periklis; Tsioufis, Costas; Iliodromitis, Efstathios; Alexopoulos, Dimitrios

2018-04-20

Approximately 5 to 7% of patients undergoing percutaneous coronary intervention (PCI) for the treatment of coronary artery disease require chronic oral anticoagulation (OAC) on top of aspirin and a P2Y 12 receptor antagonist, mainly due to non-valvular atrial fibrillation (AF). The advent of non-vitamin K antagonist oral anticoagulants (NOACs) increased treatment options, while there is cumulative evidence that dual combination of a NOAC and a P2Y 12 receptor antagonist attenuates risk of bleeding, compared to traditional triple therapy, consisting of a vitamin K antagonist (VKA), aspirin, and a P2Y 12 receptor antagonist, without significantly compromising efficacy. Greek AntiPlatElet Atrial Fibrillation (GRAPE-AF, NCT 03362788) is an observational, nationwide study of non-valvular AF patients undergoing PCI, planning to enroll over 1-year period > 500 participants in 25 tertiary and non-tertiary PCI centers in Greece. Key data to be collected pre-discharge include demographics, detailed past medical history, and antithrombotic and concomitant treatment. Patients will be followed up at 1, 6, and 12 months post hospital discharge. Αt each follow-up visit, data on antithrombotic treatment, ischemic, bleeding, and adverse events will be collected. Study's primary endpoint is clinically significant bleeding (Bleeding Academic Research Consortium, BARC ≥ 2) at 12 months, between VKAs and NOACs-treated patients, analyzed using Cox proportional hazards models, by an intention-to-treat principle. An independent endpoint committee will adjudicate all clinical events. This study aims at providing "real-world" information on current antithrombotic treatment patterns and clinical outcome of patients with non-valvular AF undergoing PCI.

Atrial fibrillation and vascular disease-a bad combination

DEFF Research Database (Denmark)

Bjerring Olesen, Jonas; Gislason, Gunnar Hilmar; Torp-Pedersen, Christian

2012-01-01

This article provides an overview of (i) the risk of stroke associated with vascular disease (acute coronary syndromes and peripheral artery disease) in patients with atrial fibrillation, (ii) the frequent coexistence of vascular disease in patients with atrial fibrillation and, (iii...... fibrillation. Indeed, patients with atrial fibrillation often had coexisting vascular disease (around 18%), and the combination of the two diseases substantially increases the risk of future cardiovascular events. The increased risk associated with peripheral artery disease in atrial fibrillation is even more...... pronounced. Patients with atrial fibrillation and stable vascular disease should be treated with oral anticoagulation only, although when these patients present with acute coronary syndrome and/or undergo coronary stenting, concomitant treatment with antiplatelet drugs is indicated. To guide antithrombotic...

Atrial Fibrillation Following Surgical Management of Ischemic Heart Disease; One Year, Single Center, Single Surgeon Results

Directory of Open Access Journals (Sweden)

Ahmet Barış Durukan

2012-08-01

Full Text Available Introduction: Postoperative atrial fibrillation is the most common arrhythmia following bypasssurgery with significant morbidity, mortality and increased healthcare costs. The aim of this studyis to determine the incidence and timing of atrial fibrillation, identify the risk factors coveringpreoperative and intraoperative periods, evaluate rate of return to sinus rhythm by disharge, andexplore the impact on postoperative outcomes in a large group of patients operated in a singlecenter by a single surgeon.Patients and Methods: Between January 2011 and January 2012, 418 patients on preoperativesinus rhythm were operated for ischemic heart disease and associated complications (left ventricleaneurysm repair and ischemic mitral insufficiency in a single center, by a single surgeon.The preoperative, intraoperative and postoperative variables were studied.Results: The mean age of the patients were 61.92 ± 10.05, and 77.5% were male. Atrial fibrillationdeveloped in 68 (16.3% patients. The incidence peaked at second day. Patients with atrialfibrillation were older (p< 0.001. Gender, preoperative comorbidities, ejection fraction, left atrialdiameter, preoperative beta-blocker use, leukocyte count, type of operation and intraoperativevariables did not affect its occurence. Intensive care unit and hospital length of stay were longer(p< 0.05. 95.5% (n= 65 of patients were in normal sinus rhythm at discharge.Conclusion: Postoperative atrial fibrillation is a popular subject with unknowns and controversialresults which may lead to wrong interpretations. We believe that every center has its own risk factors related with the population of that region. Discussion will last, but simple precautions and close monitoring will help to minimizeadverse outcomes.

Effect of renal sympathetic denervation on atrial substrate remodeling in ambulatory canines with prolonged atrial pacing.

Directory of Open Access Journals (Sweden)

Xule Wang

Full Text Available We have previously demonstrated that catheter-based renal sympathetic denervation (RSD could suppress atrial fibrillation (AF in canines with short-time rapid right atrial pacing (RAP. However, the role of renal denervation on atrial remodeling is unclear. The aim of the present study was to explore the long-term effect of RSD on the atrial remodeling during prolonged RAP. Twenty mongrel dogs were implanted with a high-frequency cardiac pacemaker with a transvenous lead inserted into the right atrial appendage. The dogs were divided into three groups: a sham-operated group (n = 6, the chronic RAP (CRAP group (n = 7, and the CRAP+RSD group (n = 7. In the CRAP+RSD group, a pacemaker was implanted 6 weeks after RSD was performed bilaterally for recovery. RAP was maintained for 5 weeks in CRAP group and CRAP+RSD group. The plasma levels of Angiotensin II and aldosterone were significantly increased in CRAP group compared with sham-operated group, but the increasing trend was inhibited in CRAP+RSD group compared with CRAP group (P<0.05. Similarly, RSD suppressed the increasing trend that prolonged RAP produced in the left atrial levels of ANP, TNF-α and IL-6. Compared with the sham-operated group, the CRAP group had significantly increased levels of caspase-3, bax and Cx40 whereas the level of Bcl-2 decreased (P<0.05. RSD markedly reduced the upregulation of caspase-3, bax and Cx40 and the downregulation of Bcl-2 expression compared with the CRAP group (P<0.05. Picric acid-sirius red staining study suggested that RSD could markedly alleviate the lesion degree of cardic fibrosis induced by CRAP (P<0.05. Immunohistochemistry results showed that the densities of TH- and GAP43- positive nerves were significantly elevated in the CRAP group compared with the sham-operated group, while RSD operation signicantly inhibited the these changes produced by CRAP. These findings suggest that renal denervation could suppress the atrial remodeling after

Recovery of Ventriculo-Atrial Conduction after Adrenaline in Patients Implanted with Pacemakers.

Science.gov (United States)

Cismaru, Gabriel; Gusetu, Gabriel; Muresan, Lucian; Rosu, Radu; Andronache, Marius; Matuz, Roxana; Puiu, Mihai; Mester, Petru; Miclaus, Maria; Pop, Dana; Mircea, Petru Adrian; Zdrenghea, Dumitru

2015-07-01

Ventriculo-atrial (VA) conduction can have negative consequences for patients with implanted pacemakers and defibrillators. There is concern whether impaired VA conduction could recover during stressful situations. Although the influence of isoproterenol and atropine are well established, the effect of adrenaline has not been studied systematically. The objective of this study was to determine if adrenaline can facilitate recovery of VA conduction in patients implanted with pacemakers. A prospective study was conducted on 61 consecutive patients during a 4-month period (April-July 2014). The presence of VA conduction was assessed during the pacemaker implantation procedure. In case of an impaired VA conduction, adrenaline infusio was used as a stress surrogate to test conduction recovery. The indications for pacemaker implantation were: sinus node dysfunction in 18 patients, atrioventricular (AV) block in 40 patients, binodal dysfunction (sinus node+ AV node) in two patients and other (carotid sinus syndrome) in one patient. In the basal state, 15/61 (24.6%) presented spontaneous VA conduction and 46/61 (75.4%) had no VA conduction. After administration of adrenaline, there was VA conduction recovery in 5/46 (10.9%) patients. Adrenaline infusion produced recovery of VA conduction in 10.9% of patients with absent VA conduction in a basal state. Recovery of VA conduction during physiological or pathological stresses could be responsible for the pacemaker syndrome, PMT episodes, or certain implantable cardiac defibrillator detection issues. © 2015 Wiley Periodicals, Inc.

Magnetic electroanatomical mapping for ablation of focal atrial tachycardias.

Science.gov (United States)

Marchlinski, F; Callans, D; Gottlieb, C; Rodriguez, E; Coyne, R; Kleinman, D

1998-08-01

Uniform success for ablation of focal atrial tachycardias has been difficult to achieve using standard catheter mapping and ablation techniques. In addition, our understanding of the complex relationship between atrial anatomy, electrophysiology, and surface ECG P wave morphology remains primitive. The magnetic electroanatomical mapping and display system (CARTO) offers an on-line display of electrical activation and/or signal amplitude related to the anatomical location of the recorded sites in the mapped chamber. A window of electrical interest is established based on signals timed from an electrical reference that usually represents a fixed electrogram recording from the coronary sinus or the atrial appendage. This window of electrical interest is established to include atrial activation prior to the onset of the P wave activity associated with the site of origin of a focal atrial tachycardia. Anatomical and electrical landmarks are defined with limited fluoroscopic imaging support and more detailed global chamber and more focal atrial mapping can be performed with minimal fluoroscopic guidance. A three-dimensional color map representing atrial activation or voltage amplitude at the magnetically defined anatomical sites is displayed with on-line data acquisition. This display can be manipulated to facilitate viewing from any angle. Altering the zoom control, triangle fill threshold, clipping plane, or color range can all enhance the display of a more focal area of interest. We documented the feasibility of using this single mapping catheter technique for localizing and ablating focal atrial tachycardias. In a consecutive series of 8 patients with 9 focal atrial tachycardias, the use of the single catheter CARTO mapping system was associated with ablation success in all but one patient who had a left atrial tachycardia localized to the medial aspect of the orifice of the left atrial appendage. Only low power energy delivery was used in this patient because of the

Metabolic Syndrome Remodels Electrical Activity of the Sinoatrial Node and Produces Arrhythmias in Rats

Science.gov (United States)

Albarado-Ibañez, Alondra; Avelino-Cruz, José Everardo; Velasco, Myrian; Torres-Jácome, Julián; Hiriart, Marcia

2013-01-01

In the last ten years, the incidences of metabolic syndrome and supraventricular arrhythmias have greatly increased. The metabolic syndrome is a cluster of alterations, which include obesity, hypertension, hypertriglyceridemia, glucose intolerance and insulin resistance, that increase the risk of developing, among others, atrial and nodal arrhythmias. The aim of this study is to demonstrate that metabolic syndrome induces electrical remodeling of the sinus node and produces arrhythmias. We induced metabolic syndrome in 2-month-old male Wistar rats by administering 20% sucrose in the drinking water. Eight weeks later, the rats were anesthetized and the electrocardiogram was recorded, revealing the presence of arrhythmias only in treated rats. Using conventional microelectrode and voltage clamp techniques, we analyzed the electrical activity of the sinoatrial node. We observed that in the sinoatrial node of “metabolic syndrome rats”, compared to controls, the spontaneous firing of all cells decreased, while the slope of the diastolic depolarization increased only in latent pacemaker cells. Accordingly, the pacemaker currents If and Ist increased. Furthermore, histological analysis showed a large amount of fat surrounding nodal cardiomyocytes and a rise in the sympathetic innervation. Finally, Poincaré plot denoted irregularity in the R-R and P-P ECG intervals, in agreement with the variability of nodal firing potential recorded in metabolic syndrome rats. We conclude that metabolic syndrome produces a dysfunction SA node by disrupting normal architecture and the electrical activity, which could explain the onset of arrhythmias in rats. PMID:24250786

Electrical remodeling and atrial dilation during atrial tachycardia are influenced by ventricular rate : Role of developing tachycardiomyopathy

NARCIS (Netherlands)

Schoonderwoerd, BA; Van Gelder, IC; Van Veldhuisen, DJ; Tieleman, RG; Grandjean, JG; Bel, KJ; Allessie, MA; Crijns, HJGM

2001-01-01

Atrial Remodeling in Tachycardiomyopathy. Introduction: Atrial fibrillation (AF) and congestive heart failure (CHF) are two clinical entities that often coincide. Our aim was to establish the influence of concomitant high ventricular rate and consequent development of CHF on electrical remodeling

Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

Directory of Open Access Journals (Sweden)

Natalia Smorodinova

Full Text Available Atrial fibrillation (AF is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients.The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR.We examined 46 subjects (19 with AF, and 27 in SR undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atrial tissue were examined using immunohistochemistry.The number of CD3+ T-lymphocytes and CD68-KP1+ cells were elevated in the left atrial myocardium of patients with AF compared to those in SR. Immune cell infiltration of LA was related to the rhythm, but not to age, body size, LA size, mitral regurgitation grade, type of surgery, systemic markers of inflammation or presence of diabetes or hypertension. Most of CD68-KP1+ cells corresponded to dendritic cell population based on their morphology and immunoreactivity for DC-SIGN. The numbers of mast cells and CD20+ B-lymphocytes did not differ between AF and SR patients. No foci of inflammation were detected in any sample.An immunohistochemical analysis of samples from patients undergoing open heart surgery showed moderate and site-specific increase of inflammatory cells in the atrial myocardium of patients with AF compared to those in SR, with prevailing population of monocyte-macrophage lineage. These cells and their cytokine products may play a role in atrial remodeling and AF persistence.

Sino - nasal surgery in the sub-Saharan Africa: A critical appraisal ...

African Journals Online (AJOL)

Background: Sino - nasal surgery poses a great challenge to practicing ear, nose and throat surgeons in the sub- Saharan Africa where facilities are inadequate and most patients are distantly located from the few hospitals available in this region. Method: A retrospective study of 79 patients who had nasal and paranasal ...

Atrial fibrillation

African Journals Online (AJOL)

ABEOLUGBENGAS

Mean blood pressures were 126.03± ... optimal. Keywords: Atrial fibrillation, thrombosis, CHADS2 Score, stroke risk, hypertensive heart disease, ... general population and the average age group ... Appendix 1) to stratify the stroke risk and we.

Atrial electromechanical delay in patients undergoing heart transplantation

Directory of Open Access Journals (Sweden)

Mustafa Bulut, MD

2017-04-01

Conclusion: Inter-AEMD and intra-AEMD were prolonged in patients who underwent heart transplantation as compared to a control population. This may explain the increased atrial fibrillation and other atrial arrhythmia incidences associated with the biatrial anastomosis heart transplantation technique and may contribute to the treatment of atrial fibrillation in this special patient group.

Does Left Atrial Volume and Pulmonary Venous Anatomy Predict the Outcome of Catheter Ablation of Atrial Fibrillation ?

NARCIS (Netherlands)

Hof, Irene; Chilukuri, Karuna; Arbab-Zadeh, Armin; Scherr, Daniel; Dalal, Darshan; Nazarian, Saman; Henrikson, Charles; Spragg, David; Berger, Ronald; Marine, Joseph; Calkins, Hugh

Introduction: Preprocedural factors may be helpful in selecting patients with atrial fibrillation (AF) for treatment with catheter ablation and in making an assumption regarding their prognosis. The aims of this study were to investigate whether left atrial (LA) volume and pulmonary venous (PV)

SinoProbe - A Multidisciplinary Research Program of Earth Sciences in China (Invited)

Science.gov (United States)

Dong, S.; Li, T.

2010-12-01

China occupies a large region of central and eastern Asia and holds keys to resolving several first-order problems in Earth Sciences. Besides the importance in Earth Science research, the rapid growth of Chinese economy also demands a comprehensive and systematic evaluation of its natural resources and the impacts of geohazards on its societal development. In order to address the above issues, the Chinese government had initiated a new multidisciplinary research project in Earth Sciences - the SinoProbe Program. Its fundamental goal is to determine the three-dimensional structure, composition distribution, and geological evolution of the Chinese continental lithosphere. The results of the SinoProbe Program are expected to have broad impacts on the Chinese society and economy. In particular, the program will greatly enhance our current understanding on (1) the forming and distribution of mineral resources in the nation, (2) the locations and recurrence histories of major active fault zones capable of generating large earthquakes in highly populated regions, and (3) the distribution of major hazard-prone regions induced by geological processes. In 2009, more than 720 investigators and 70 engineers from Chinese institutions are currently involved with the research program. Sinoprobe hope that the joint forces by Chinese and international researchers will bring in modern approaches, new analytical tools, and advanced exploration technology into the successful operation of the program. In past year, 1,960km long seismic reflection profiling with broadband seismological studies and MT surveys separated from 6 profiles in China continent have completed. MT array coved the North China craton by 1°×1° network and 3-D exploration in larger ore deposits in selected area were carried out. A scientific drilling area operated in Tibet. We started to establish a geochemical reference framework for the values of 76 elements in a grid network with data-point spacing of 160 km in

Concomitant atrial fibrillation surgery for people undergoing cardiac surgery

Science.gov (United States)

Huffman, Mark D; Karmali, Kunal N; Berendsen, Mark A; Andrei, Adin-Cristian; Kruse, Jane; McCarthy, Patrick M; Malaisrie, S C

2016-01-01

Background People with atrial fibrillation (AF) often undergo cardiac surgery for other underlying reasons and are frequently offered concomitant AF surgery to reduce the frequency of short- and long-term AF and improve short- and long-term outcomes. Objectives To assess the effects of concomitant AF surgery among people with AF who are undergoing cardiac surgery on short-term and long-term (12 months or greater) health-related outcomes, health-related quality of life, and costs. Search methods Starting from the year when the first “maze” AF surgery was reported (1987), we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (March 2016), MEDLINE Ovid (March 2016), Embase Ovid (March 2016), Web of Science (March 2016), the Database of Abstracts of Reviews of Effects (DARE, April 2015), and Health Technology Assessment Database (HTA, March 2016). We searched trial registers in April 2016. We used no language restrictions. Selection criteria We included randomised controlled trials evaluating the effect of any concomitant AF surgery compared with no AF surgery among adults with preoperative AF, regardless of symptoms, who were undergoing cardiac surgery for another indication. Data collection and analysis Two review authors independently selected studies and extracted data. We evaluated the risk of bias using the Cochrane ‘Risk of bias’ tool. We included outcome data on all-cause and cardiovascular-specific mortality, freedom from atrial fibrillation, flutter, or tachycardia off antiarrhythmic medications, as measured by patient electrocardiographic monitoring greater than three months after the procedure, procedural safety, 30-day rehospitalisation, need for post-discharge direct current cardioversion, health-related quality of life, and direct costs. We calculated risk ratios (RR) for dichotomous data with 95% confidence intervals (CI) using a fixed-effect model when heterogeneity was low (I2 ≤ 50%) and random

Exercise-based cardiac rehabilitation for adults with atrial fibrillation

DEFF Research Database (Denmark)

Risom, Signe Stelling; Zwisler, Ann-Dorthe; Johansen, Pernille Palm

2017-01-01

BACKGROUND: Exercise-based cardiac rehabilitation may benefit adults with atrial fibrillation or those who had been treated for atrial fibrillation. Atrial fibrillation is caused by multiple micro re-entry circuits within the atrial tissue, which result in chaotic rapid activity in the atria....... OBJECTIVES: To assess the benefits and harms of exercise-based rehabilitation programmes, alone or with another intervention, compared with no-exercise training controls in adults who currently have AF, or have been treated for AF. SEARCH METHODS: We searched the following electronic databases; CENTRAL...... the benefits and harms of exercise-based cardiac rehabilitation for adults with atrial fibrillation on patient-relevant outcomes....

Teaching China in Scotland's Secondary Schools as Sino-Scottish Engagement Intensifies

Science.gov (United States)

Oates, John Vincent

2011-01-01

At a time of burgeoning Sino-Scottish engagement, and the introduction of a new national education policy, "Curriculum for Excellence" designed to enhance teacher autonomy, this paper draws on the national response of Modern Studies teachers who are the only group of Scottish teachers to have the (voluntary) option of including the study…

Entropy measurements in paroxysmal and persistent atrial fibrillation

International Nuclear Information System (INIS)

Cervigón, R; Moreno, J; Pérez-Villacastín, J; Reilly, R B; Millet, J; Castells, F

2010-01-01

Recent studies on atrial fibrillation (AF) have identified different activation patterns in paroxysmal and persistent AF. In this study, bipolar intra-atrial registers from 28 patients (14 paroxysmal AF and 14 persistent AF) were analyzed in order to find out regional differences in the organization in both types of arrhythmias. The organization of atrial electrical activity was assessed in terms of nonlinear parameters, such as entropy measurements. Results showed differences between the atrial chambers with a higher disorganization in the left atrium in paroxysmal AF patients and a more homogenous behavior along the atria in persistent AF patients

Sino-Japanese Interaction via Chinese Junks in the Edo Period

OpenAIRE

MATSUURA, Akira

2010-01-01

To maintain its policy of national isolation during the Edo period, Japan restricted contact with the outside world to Dutch merchant ships and Chinese junks at the Japanese port of Nagasaki. Sino-Japanese interaction consisted not only of trade in goods, but also of cultural and scholarly exchanges. This paper will examine how this unofficial trade affected both Japan and China from a cultural perspective.

Extreme variation in the atrial septation of caecilians (Amphibia: Gymnophiona)

Science.gov (United States)

de Bakker, Desiderius M; Wilkinson, Mark; Jensen, Bjarke

2015-01-01

Caecilians (order Gymnophiona) are elongate, limbless, snake-like amphibians that are the sister-group (closest relatives) of all other recent amphibians (frogs and salamanders). Little is known of their cardiovascular anatomy and physiology, but one nearly century old study suggests that Hypogeophis (family Indotyphlidae), commonly relied upon as a representative caecilian species, has atrial septation in the frontal plane and more than one septum. In contrast, in other vertebrates there generally is one atrial septum in the sagittal plane. We studied the adult heart of Idiocranium (also Indotyphlidae) using immunohistochemistry and confirm that the interatrial septum is close to the frontal plane. Additionally, a parallel right atrial septum divides three-fourths of the right atrial cavity of this species. Idiocranium embryos in the Hill collection reveal that atrial septation initiates in the sagittal plane as in other tetrapods. Late developmental stages, however, see a left-ward shift of visceral organs and a concordant rotation of the atria that reorients the atrial septa towards the frontal plane. The gross anatomies of species from six other caecilian families reveal that (i) the right atrial septum developed early in caecilian evolution (only absent in Rhinatrematidae) and that (ii) rotation of the atria evolved later and its degree varies between families. In most vertebrates a prominent atrial trabeculation associates with the sinuatrial valve, the so-called septum spurium, and the right atrial septum seems homologous to this trabeculation but much more developed. The right atrial septum does not appear to be a consequence of body elongation because it is absent in some caecilians and in snakes. The interatrial septum of caecilians shares multiple characters with the atrial septum of lungfishes, salamanders and the embryonic septum primum of amniotes. In conclusion, atrial septation in caecilians is based on evolutionarily conserved structures but

Atrial infarction is a unique and often unrecognized clinical entity

Directory of Open Access Journals (Sweden)

Rosana G. G. Mendes

1999-03-01

Full Text Available A patient with heart failure and acute atrial fibrillation received the final diagnosis of atrial infarction associated with ventricular infarction based on clinical findings of ischemia in association with atrial fibrillation and heart failure (mechanisms probably involved: contractile dysfunction and loss of atrial contribution. Although a transesophageal echocardiography, which could refine the diagnosis of anatomic abnormalities, was not performed, all evidence led to the diagnosis of atrial involvement. Electrocardiographic findings were consistent with Liu's major criterion 3. Therapy with digitalis, quinidine and angiotensin-converting enzyme inhibitors was chosen, as the patient had acute pulmonary edema. The use of beta-blockers and verapamil was restricted. No other complications, such as thrombo-embolism or atrial rupture, were noted.

Atrial tachyarrhythmia in adult congenital heart disease

Science.gov (United States)

Karbassi, Arsha; Nair, Krishnakumar; Harris, Louise; Wald, Rachel M; Roche, S Lucy

2017-01-01

The adult congenital heart disease (ACHD) population continues to grow and most cardiologists, emergency room physicians and family doctors will intermittently come into contact with these patients. Oftentimes this may be in the setting of a presentation with atrial tachyarrhythmia; one of the commonest late complications of ACHD and problem with potentially serious implications. Providing appropriate initial care and ongoing management of atrial tachyarrhythmia in ACHD patients requires a degree of specialist knowledge and an awareness of certain key issues. In ACHD, atrial tachyarrhythmia is usually related to the abnormal anatomy of the underlying heart defect and often occurs as a result of surgical scar or a consequence of residual hemodynamic or electrical disturbances. Arrhythmias significantly increase mortality and morbidity in ACHD and are the most frequent reason for ACHD hospitalization. Intra-atrial reentrant tachycardia and atrial fibrillation are the most prevalent type of arrhythmia in this patient group. In hemodynamically unstable patients, urgent cardioversion is required. Acute management of the stable patient includes anticoagulation, rate control, and electrical or pharmacological cardioversion. In ACHD, rhythm control is the preferred management strategy and can often be achieved. However, in the long-term, medication side-effects can prove problematic. Electrophysiology studies and catheter ablation are important treatments modalities and in certain cases, surgical or percutaneous treatment of the underlying cardiac defect has a role. ACHD patients, especially those with complex CHD, are at increased risk of thromboembolic events and anticoagulation is usually required. Female ACHD patients of child bearing age may wish to pursue pregnancies. The risk of atrial arrhythmias is increased during pregnancy and management of atrial tachyarrhythmia during pregnancy needs specific consideration. PMID:28706585

Cryoballoon Ablation for Atrial Fibrillation

Directory of Open Access Journals (Sweden)

Jason G. Andrade, MD

2012-03-01

Full Text Available Focal point-by-point radiofrequency catheter ablation has shown considerable success in the treatment of paroxysmal atrial fibrillation. However, it is not without limitations. Recent clinical and preclinical studies have demonstrated that cryothermal ablation using a balloon catheter (Artic Front©, Medtronic CryoCath LP provides an effective alternative strategy to treating atrial fibrillation. The objective of this article is to review efficacy and safety data surrounding cryoballoon ablation for paroxysmal and persistent atrial fibrillation. In addition, a practical step-by-step approach to cryoballoon ablation is presented, while highlighting relevant literature regarding: 1 the rationale for adjunctive imaging, 2 selection of an appropriate cryoballoon size, 3 predictors of efficacy, 4 advanced trouble-shooting techniques, and 5 strategies to reduce procedural complications, such as phrenic nerve palsy.

Never So Important——First Sino-US Strategic and Economic Dialogue

Institute of Scientific and Technical Information of China (English)

Wen Xiu

2009-01-01

@@ The first Sino-US Strategic and Economic Dialogue was held on July 27 and 28,2009 in Washington.Either before or during the dialogue,PRC and USA attached great importance to it.The former Strategic Dialogue and the biannual Strategic Economic Dialogue were initiated by the two heads of state in 2005 and 2006 respectively.

Left atrial function in heart failure with impaired and preserved ejection fraction.

Science.gov (United States)

Fang, Fang; Lee, Alex Pui-Wai; Yu, Cheuk-Man

2014-09-01

Left atrial structural and functional changes in heart failure are relatively ignored parts of cardiac assessment. This review illustrates the pathophysiological and functional changes in left atrium in heart failure as well as their prognostic value. Heart failure can be divided into those with systolic dysfunction and heart failure with preserved ejection fraction (HFPEF). Left atrial enlargement and dysfunction commonly occur in systolic heart failure, in particular, in idiopathic dilated cardiomyopathy. Atrial enlargement and dysfunction also carry important prognostic value in systolic heart failure, independently of known parameters such as left ventricular ejection fraction. In HFPEF, there is evidence of left atrial enlargement, impaired atrial compliance, and reduction of atrial pump function. This occurs not only at rest but also during exercise, indicating significant impairment of atrial contractile reserve. Furthermore, atrial dyssynchrony is common in HFPEF. These factors further contribute to the development of new onset or progression of atrial arrhythmias, in particular, atrial fibrillation. Left atrial function is an integral part of cardiac function and its structural and functional changes in heart failure are common. As changes of left atrial structure and function have different clinical implications in systolic heart failure and HFPEF, routine assessment is warranted.

The 3rd Sino-Japan nuclear medicine conference

International Nuclear Information System (INIS)

1999-01-01

The 3rd Sino-Japan Nuclear Medicine Conference was hold on May 11-13, 1999 in Xi'an of China by Chinese Society of Nuclear Medicine, Japanese Society of Nuclear Medicine, Chinese Medicine Association and Japan-China Medicine Association. 62 articles were published in the proceeding of the conference. The contents of the articles include development and application of the radioisotopes (such as Tc-99, I-125, I-131, F-18, In-111, Tl-201, Ga-67, Sm-153, Re-188) and its radiopharmaceuticals, but application also include radiotherapy and diagnosis in the oncology and pathology by SPECT and PET

Atrial remodelling in atrial fibrillation: CaMKII as a nodal proarrhythmic signal

Science.gov (United States)

Mesubi, Olurotimi O.; Anderson, Mark E.

2016-01-01

CaMKII is a serine–threonine protein kinase that is abundant in myocardium. Emergent evidence suggests that CaMKII may play an important role in promoting atrial fibrillation (AF) by targeting a diverse array of proteins involved in membrane excitability, cell survival, calcium homeostasis, matrix remodelling, inflammation, and metabolism. Furthermore, CaMKII inhibition appears to protect against AF in animal models and correct proarrhythmic, defective intracellular Ca2+ homeostasis in fibrillating human atrial cells. This review considers current concepts and evidence from animal and human studies on the role of CaMKII in AF. PMID:26762270

Fenofibrate inhibits atrial metabolic remodelling in atrial fibrillation through PPAR-α/sirtuin 1/PGC-1α pathway.

Science.gov (United States)

Liu, Guang-Zhong; Hou, Ting-Ting; Yuan, Yue; Hang, Peng-Zhou; Zhao, Jing-Jing; Sun, Li; Zhao, Guan-Qi; Zhao, Jing; Dong, Jing-Mei; Wang, Xiao-Bing; Shi, Hang; Liu, Yong-Wu; Zhou, Jing-Hua; Dong, Zeng-Xiang; Liu, Yang; Zhan, Cheng-Chuang; Li, Yue; Li, Wei-Min

2016-03-01

Atrial metabolic remodelling is critical for the process of atrial fibrillation (AF). The PPAR-α/sirtuin 1 /PPAR co-activator α (PGC-1α) pathway plays an important role in maintaining energy metabolism. However, the effect of the PPAR-α agonist fenofibrate on AF is unclear. Therefore, the aim of this study was to determine the effect of fenofibrate on atrial metabolic remodelling in AF and explore its possible mechanisms of action. The expression of metabolic proteins was examined in the left atria of AF patients. Thirty-two rabbits were divided into sham, AF (pacing with 600 beats·min(-1) for 1 week), fenofibrate treated (pretreated with fenofibrate before pacing) and fenofibrate alone treated (for 2 weeks) groups. HL-1 cells were subjected to rapid pacing in the presence or absence of fenofibrate, the PPAR-α antagonist GW6471 or sirtuin 1-specific inhibitor EX527. Metabolic factors, circulating biochemical metabolites, atrial electrophysiology, adenine nucleotide levels and accumulation of glycogen and lipid droplets were assessed. The PPAR-α/sirtuin 1/PGC-1α pathway was significantly inhibited in AF patients and in the rabbit/HL-1 cell models, resulting in a reduction of key downstream metabolic factors; this effect was significantly restored by fenofibrate. Fenofibrate prevented the alterations in circulating biochemical metabolites, reduced the level of adenine nucleotides and accumulation of glycogen and lipid droplets, reversed the shortened atrial effective refractory period and increased risk of AF. Fenofibrate inhibited atrial metabolic remodelling in AF by regulating the PPAR-α/sirtuin 1/PGC-1α pathway. The present study may provide a novel therapeutic strategy for AF. © 2016 The British Pharmacological Society.

Effect of atrial systole on canine and porcine coronary blood flow.

Science.gov (United States)

Bellamy, R F

1981-09-01

A feature of phasic coronary flow patterns recorded in conscious chronically instrumented dogs is the atrial cove--a transient depression of arterial flow that occurs during atrial systole. The association between the hemodynamic effects of atrial systole and the atrial cove was studied in anesthetized dogs and pigs with complete heart block. Many atrial coves are available for study in these preparations because atrial activity continues unabated during the diastolic ventricular arrest that follows cessation of electrical pacing. The effect of atrial systole is to translate the pressure-flow relation found during diastole to a higher intercept pressure without change in slope. The increase in the intercept pressure equals the increase in intramyocardial pressure measured with microtransducers embedded in the left ventricular wall. The decrement in flow during the atrial cove is a direct function of the change in intramyocardial pressure and an inverse function of coronary vascular resistance. Each atrial systole is associated with a forward flow transient in the coronary veins, the peak of which occurs at the same instant as does the nadir of atrial flow. These data suggest that the coronary vessels are acting as collapsible tubes and that the waterfall model of the coronary circulation is applicable. The following sequence is proposed to account for the atrial cove. Atrial systole ejects a bolus of blood into the left ventricle increasing both ventricular cavity and intramyocardial pressures. The increase in intramyocardial pressure raises the back pressure opposing coronary flow, reducing the arterial perfusion pressure gradient and causing flow to fall.

Left atrial accessory appendages, diverticula, and left-sided septal pouch in multi-slice computed tomography. Association with atrial fibrillation and cerebrovascular accidents.

Science.gov (United States)

Hołda, Mateusz K; Koziej, Mateusz; Wszołek, Karolina; Pawlik, Wiesław; Krawczyk-Ożóg, Agata; Sorysz, Danuta; Łoboda, Piotr; Kuźma, Katarzyna; Kuniewicz, Marcin; Lelakowski, Jacek; Dudek, Dariusz; Klimek-Piotrowska, Wiesława

2017-10-01

The aim of this study is to provide a morphometric description of the left-sided septal pouch (LSSP), left atrial accessory appendages, and diverticula using cardiac multi-slice computed tomography (MSCT) and to compare results between patient subgroups. Two hundred and ninety four patients (42.9% females) with a mean of 69.4±13.1years of age were investigated using MSCT. The presence of the LSSP, left atrial accessory appendages, and diverticula was evaluated. Multiple logistic regression analysis was performed to check whether the presence of additional left atrial structures is associated with increased risk of atrial fibrillation and cerebrovascular accidents. At least one additional left atrial structure was present in 51.7% of patients. A single LSSP, left atrial diverticulum, and accessory appendage were present in 35.7%, 16.0%, and 4.1% of patients, respectively. After adjusting for other risk factors via multiple logistic regression, patients with LSSP are more likely to have atrial fibrillation (OR=2.00, 95% CI=1.14-3.48, p=0.01). The presence of a LSSP was found to be associated with an increased risk of transient ischemic attack using multiple logistic regression analysis after adjustment for other risk factors (OR=3.88, 95% CI=1.10-13.69, p=0.03). In conclusion LSSPs, accessory appendages, and diverticula are highly prevalent anatomic structures within the left atrium, which could be easily identified by MSCT. The presence of LSSP is associated with increased risk for atrial fibrillation and transient ischemic attack. Copyright © 2017 Elsevier B.V. All rights reserved.

Vernakalant hydrochloride for the treatment of atrial fibrillation.

Science.gov (United States)

Kozlowski, Dariusz; Budrejko, Szymon; Lip, Gregory Y H; Mikhailidis, Dimitri P; Rysz, Jacek; Raczak, Grzegorz; Banach, Maciej

2009-12-01

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Rhythm control strategy for AF is limited by drug toxicity and side effects, and recent trials have shown that this strategy is not superior to a rate control one. New antiarrhythmic drugs, free of undesired effects, would enhance rhythm control, with the possibility of sinus rhythm restoration and maintenance. A promising find in the search for new antiarrhythmic therapies is atrial-tissue specific ion channels. The findings that the ultrarapid delayed rectifier (I(Kur)) and the inwardly rectifying, acetylcholine-regulated current (I(K-Ach)) exist in atrial but not ventricular tissue increase the probability that atrioselective drugs without ventricular proarrhythmic toxicity can be developed for treatment of patients with AF. There are also other potential targets for atrial-selective therapy: transient outward current (I(to)), rapidly and slowly activating delayed rectifier currents (I(Kr) and I(Ks)), atrial sodium current (I(Na)) and atrially expressed connexins. New drugs under development with promising atrial-selectivity include: tertiapin, NIP-142, NIP-141, JTV-519, AVE0118, AVE1231, DPO-1, AZD7009 and many others. Among such new agents, vernakalant hydrochloride is currently in an advanced phase of development and has already been evaluated in clinical trials. In this overview, we describe the history and current state of developmental process of the drug, as well as its mechanism of action and influence on electrophysiological parameters. Vernakalant seems to be effective in terminating recent-onset AF, but is not efficacious in long-lasting AF and atrial flutter. The drug may be relatively free of proarrhythmic effects, and exerts a protective effect on ventricular tissue and ventricular repolarization. It is expected that the intravenous formulation will soon be approved for the pharmacological termination of recent-onset AF.

Direct Proof of Endo-Epicardial Asynchrony of the Atrial Wall During Atrial Fibrillation in Humans.

Science.gov (United States)

de Groot, Natasja; van der Does, Lisette; Yaksh, Ameeta; Lanters, Eva; Teuwen, Christophe; Knops, Paul; van de Woestijne, Pieter; Bekkers, Jos; Kik, Charles; Bogers, Ad; Allessie, Maurits

2016-05-01

The presence of focal fibrillation waves during atrial fibrillation (AF) can, besides ectopic activity, also be explained by asynchronous activation of the atrial endo- and epicardial layer and transmurally propagating fibrillation waves. To provide direct proof of endo-epicardial asynchrony, we performed simultaneous high-resolution mapping of the right atrial endo- and epicardial wall during AF in humans. Intraoperative mapping of the endo- and epicardial right atrial wall was performed during (induced) AF in 10 patients with AF (paroxysmal: n=3; persistent: n=4; and longstanding persistent: n=3) and 4 patients without a history of AF. A clamp made of 2 rectangular 8×16 electrode arrays (interelectrode distance 2 mm) was inserted into the incision in the right atrial appendage. Recordings of 10 seconds of AF were analyzed to determine the incidence of asynchronous endo-epicardial activation times (≥15 ms) of opposite electrodes. Asynchronous endo-epicardial activation ranged between 0.9 and 55.9% without preference for either side. Focal waves appeared equally frequent at endocardium and epicardium (11% versus 13%; ITALIC! P=0.18). Using strict criteria for breakthrough (presence of an opposite wave within 4 mm and ≤14 ms before the origin of the focal wave), the majority (65%) of all focal fibrillation waves could be attributed to endo-epicardial excitation. We provided the first evidence for asynchronous activation of the endo-epicardial wall during AF in humans. Endo-epicardial asynchrony may play a major role in the pathophysiology of AF and may offer an explanation why in some patients therapy fails. © 2016 American Heart Association, Inc.

Spatio-temporal evolution of efficient subglacial water discharge at Lemon Creek Glacier, Alaska

Science.gov (United States)

Bartholomaus, T. C.; Labedz, C. R.; Amundson, J. M.; Gimbert, F.; Tsai, V. C.; Vore, M. E.; Karplus, M. S.

2017-12-01

The impact of subglacial hydrology on glacier motion, glacier erosion and sediment transport, and submarine melt is well established. However, despite its importance, critical gaps in our understanding of subglacial hydrology and its seasonal evolution remain, in large part due to the challenge of making observations of glacier beds. Thus far, no spatially extensive, temporally continuous observations of subglacial water discharge exist. Seismic signals produced by subglacial water flow, and which correlate with subglacial water discharge, can meet this need. Here, we present the first observations from a 2017 summer seismic, geodetic, and hydrologic experiment. Our experiment seeks to better understand the evolution of efficient subglacial drainage and water storage through data collection and analysis at Lemon Creek Glacier, a 5.7 km-long glacier with a gauged outlet in Southeast Alaska. Data with nested spatial resolutions create an unparalleled perspective of subglacial discharge and its seasonal evolution. Six broadband seismometers and two GPS receivers installed for 80 days provide a long-term view of subglacial discharge and its impact on glacier dynamics. More than 100 nodes, installed approximately every 250 m over the glacier surface ( 13 nodes per 1 km^2) and deployed for up to 25 days, reveal the detailed spatial pattern of glaciohydraulic tremor amplitudes. These nodes enable us to more precisely infer the locations of subglacial discharge and its change, as well as better interpret long-term patterns of glaciohydraulic tremor observed by the broadband seismometers. We infer the subglacial response to hydraulic transients over the duration of the deployment through examination of intermittent melt and rain events, and the abrupt drainage of a glacier-dammed lake. These observations demonstrate the promise of seismology to significantly advance our understanding of glacier hydrology and associated glaciological processes.

Risk of atrial fibrillation among bisphosphonate users: a multicenter, population-based, Italian study.

Science.gov (United States)

Herrera, L; Leal, I; Lapi, F; Schuemie, M; Arcoraci, V; Cipriani, F; Sessa, E; Vaccheri, A; Piccinni, C; Staniscia, T; Vestri, A; Di Bari, M; Corrao, G; Zambon, A; Gregori, D; Carle, F; Sturkenboom, M; Mazzaglia, G; Trifiro, G

2015-05-01

Bisphosphonate treatment is used to prevent bone fractures. A controversial association of bisphosphonate use and risk of atrial fibrillation has been reported. In our study, current alendronate users were associated with a higher risk of atrial fibrillation as compared with those who had stopped bisphosphonate (BP) therapy for more than 1 year. Bisphosphonates are widely used to prevent bone fractures. Controversial findings regarding the association between bisphosphonate use and the risk of atrial fibrillation (AF) have been reported. The aim of this study was to evaluate the risk of AF in association with BP exposure. We performed a nested case-control study using the databases of drug-dispensing and hospital discharge diagnoses from five Italian regions. The data cover a period ranging from July 1, 2003 to December 31, 2006. The study population comprised new users of bisphosphonates aged 55 years and older. Patients were followed from the first BP prescription until an occurrence of an AF diagnosis (index date, i.e., ID), cancer, death, or the end of the study period, whichever came first. For the risk estimation, any AF case was matched by age and sex to up to 10 controls from the same source population. A conditional logistic regression was performed to obtain the odds ratio with 95% confidence intervals (CI). The BP exposure was classified into current (reference point. A subgroup analysis by individual BP was then carried out. In comparison with distant past users of BP, current users of BP showed an almost twofold increased risk of AF: odds ratio (OR) = 1.78 and 95% CI = 1.46-2.16. Specifically, alendronate users were mostly associated with AF as compared with distant past use of BP (OR, 1.97; 95% CI, 1.59-2.43). In our nested case-control study, current users of BP are associated with a higher risk of atrial fibrillation as compared with those who had stopped BP treatment for more than 1 year.

Long-term biatrial recordings in post-operative atrial fibrillation.

Science.gov (United States)

Masè, M; Graffigna, A; Sinelli, S; Pallaoro, G; Nollo, G; Ravelli, F

2010-01-01

Although atrial fibrillation (AF) is a common complication of cardiac surgery, its pathophysiology remains unclear. The study of post-operative AF demands for the recording of cardiac electrical activity in correspondence of AF onset and progression. Long-term recordings in post-surgery patients could provide this information, but, to date, have been limited to surface signals, which precludes a characterization of the arrhythmic triggers and substrate. In this study we demonstrate the feasibility of a continuous long-term recording of atrial electrical activities from the right and left atria in post-surgery patients. Local atrial epicardial electrograms are acquired by positioning temporary pacing wires in the right and left atria at the end of the intervention, while three day recordings are obtained by a digital holter recorder, adapted to epicardial signal features. The capability of the system to map local atrial activity and the possibility to obtain quantitative information on atrial rate and synchronization from the processed epicardial signals are proven in representative examples. The quantitative description of local atrial properties opens new perspective in the investigation of post-surgery AF.

Atrial fibrillation

DEFF Research Database (Denmark)

Olesen, Morten S; Nielsen, Morten W; Haunsø, Stig

2014-01-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting 1-2% of the general population. A number of studies have demonstrated that AF, and in particular lone AF, has a substantial genetic component. Monogenic mutations in lone and familial AF, although rare, have been recognized...

phylo-node: A molecular phylogenetic toolkit using Node.js.

Science.gov (United States)

O'Halloran, Damien M

2017-01-01

Node.js is an open-source and cross-platform environment that provides a JavaScript codebase for back-end server-side applications. JavaScript has been used to develop very fast and user-friendly front-end tools for bioinformatic and phylogenetic analyses. However, no such toolkits are available using Node.js to conduct comprehensive molecular phylogenetic analysis. To address this problem, I have developed, phylo-node, which was developed using Node.js and provides a stable and scalable toolkit that allows the user to perform diverse molecular and phylogenetic tasks. phylo-node can execute the analysis and process the resulting outputs from a suite of software options that provides tools for read processing and genome alignment, sequence retrieval, multiple sequence alignment, primer design, evolutionary modeling, and phylogeny reconstruction. Furthermore, phylo-node enables the user to deploy server dependent applications, and also provides simple integration and interoperation with other Node modules and languages using Node inheritance patterns, and a customized piping module to support the production of diverse pipelines. phylo-node is open-source and freely available to all users without sign-up or login requirements. All source code and user guidelines are openly available at the GitHub repository: https://github.com/dohalloran/phylo-node.

Variable use of amiodarone is associated with a greater risk of recurrence of atrial fibrillation in the critically ill.

Science.gov (United States)

Mitrić, Goran; Udy, Andrew; Bandeshe, Hiran; Clement, Pierre; Boots, Rob

2016-04-02

Atrial fibrillation is a common rhythm disturbance in the general medical-surgical intensive care unit. Amiodarone is a popular drug in this setting but evidence to inform clinical practice remains scarce. We aimed to identify whether variation in the clinical use of amiodarone was associated with recurrent atrial fibrillation. This was a retrospective audit of 177 critically ill patients who developed new-onset atrial fibrillation after admission to a tertiary level medical-surgical trauma intensive care unit. Patterns of amiodarone prescription (including dosage schedule and duration) were assessed in relation to recurrence of atrial fibrillation during the intensive care unit stay. Known recurrence risk factors, such as inotrope administration, cardiac disease indices, Charlson Comorbidity Index, magnesium concentrations, fluid balance, and potassium concentrations, were also included in adjusted analysis using forward stepwise logistic regression modelling. The cohort had a median (interquartile range) age of 69 years (60-75), Acute Physiology and Chronic Health Evalution II score of 22 (17-28) and Charlson Comorbidity Index of 2 (1-4). A bolus dose of amiodarone followed by infusion (P = 0.02), in addition to continuing amiodarone infusion through to discharge from the intensive care unit (P < 0.001), were associated with less recurrent dysrhythmia. Recurrence after successful treatment was associated with ceasing amiodarone while an inotrope infusion continued (P < 0.001), and was more common in patients with a prior history of congestive cardiac failure (P = 0.04), and a diagnosis of systemic inflammatory response syndrome (P = 0.02). Amiodarone should be administered as a bolus dose followed immediately with an infusion when treating atrial fibrillation in the medical-surgical intensive care unit. Consideration should be given to continuing amiodarone infusions in patients on inotropes until they are ceased.

Management of atrial fibrillation in the setting of heart failure

NARCIS (Netherlands)

Crijns, HJGM; VandenBerg, MP; VanGelder, IC; VanVeldhuisen, DJ

Heart failure is often complicated by atrial fibrillation. Once atrial fibrillation has started it further enhances heart failure due to uncontrolled rate with shortened filling time and provocation of tachycardiomyopathy. Absent atrial kick and irregularity of the ventricular rhythm also

Dronedarone in high-risk permanent atrial fibrillation

DEFF Research Database (Denmark)

Connolly, Stuart J; Camm, A John; Halperin, Jonathan L

2011-01-01

Dronedarone restores sinus rhythm and reduces hospitalization or death in intermittent atrial fibrillation. It also lowers heart rate and blood pressure and has antiadrenergic and potential ventricular antiarrhythmic effects. We hypothesized that dronedarone would reduce major vascular events...... in high-risk permanent atrial fibrillation....

Assistência de enfermagem a paciente com fibrilação atrial Asistencia de enfermería al paciente con fibrilación atrial Nursing assistance to patients with atrial fibrillation

Directory of Open Access Journals (Sweden)

Lutgarde Magda Suzanne Vanheusden

2006-04-01

Full Text Available Este estudo tem por objetivo apresentar uma revisão atualizada sobre as questões que envolvem a assistência à paciente que desenvolve fibrilação atrial. Essa revisão discute a condição complexa dessa taquiarritmia que influencia a mortalidade, morbidade, abordando o seu elevado custo para o sistema de saúde. A assistência e o importante papel da educação para a enfermagem nessa área estão sendo discutidos. Como a prevalência da fibrilação atrial aumenta com a idade e o Brasil tem uma população idosa cada vez mais crescente, a enfermagem enfrenta atualmente o desafio para cuidar dessa população que apresenta necessidades variadas.Este estudio tiene por objetivo presentar una revisión actualizada sobre las cuestiones que envuelven la asistencia al paciente que desarrolla fibrilación atrial. Esa revisión discute la condición compleja de esa taquiarritmia que influencia la morbidad, mortalidad, enfocando el costo que es muy grande para el sistema de salud. Se discute también la asistencia y el importante papel de la educación para la enfermería en esa área. Como la prevalencia de la fibrilación atrial aumenta con la edad y como el Brasil tiene una población de ancianos cada vez más creciente, la enfermería, actualmente, enfrenta el desafío para cuidar de esa población que presenta necesidades variadas.The objective of this study is to present an up to date revision about the assistance of the patient that develops atrial fibrilation. This revision raises the discussion on the complexity of atrial fibrillation that influences the mortality, morbidity, and the high cost for the health system. The assistance and the important paper of education of nursing on atrial fibrillation are here discussed. The population of Brazil is increasing in time and age consequently the prevalence of atrial fibrillation is also increasing. Thus, nursing faces the current challenge to take care of this specific population that presents

The circadian variation of premature atrial contractions

DEFF Research Database (Denmark)

Larsen, Bjørn Strøier; Kumarathurai, Preman; Nielsen, Olav W

2016-01-01

AIMS: The aim of the study was to assess a possible circadian variation of premature atrial contractions (PACs) in a community-based population and to determine if the daily variation could be used to assess a more vulnerable period of PACs in predicting later incidence of atrial fibrillation (AF...... variation in heart rate. After adjusting for relevant risk factors, the risk of AF was equal in all time intervals throughout the day. CONCLUSION: Premature atrial contractions showed a circadian variation in subjects with frequent PACs. No specific time interval of the day was more predictive of AF than...

Atrial anatomy and function postcardioversion: insights from transthoracic and transesophageal echocardiography.

Science.gov (United States)

Manning, W J; Silverman, D I

1996-01-01

Echocardiography provides a valuable tool for the evaluation and assessment of atrial function in patients with atrial fibrilation (AF). Atrial morphology after restoration of sinus rhythm is dynamic, with a decrease in atrial size if sinus rhythm is maintained and atrial growth among those with sustained AF. Restoration of electrocardiographic sinus rhythm is frequently accompanied by relatively depressed atrial mechanical function, with recovery that appears to be related to multiple factors, including the duration of AF before cardioversion and the mode of cardioversion. Such delay appears to confer ongoing risk for thrombus formation and thromboembolism in the days after cardioversion and argues strongly for the need to maintain therapeutic anticoagulation during the pericardioversion and postcardioversion period.

Newer Anticoagulants for Non-Valvular Atrial Fibrillation

Directory of Open Access Journals (Sweden)

Joseph M. Harburger

2012-05-01

Full Text Available Non-valvular atrial fibrillation is a recognized risk factor for stroke and systemic embolism. It has been clearly established that warfarin reduces the risk of stroke and systemic embolism in persons with atrial fibrillation and additional risk factors for stroke. The use of warfarin, however, requires frequent monitoring, and there is great variability in patient response to warfarin. Warfarin interacts with several medications and foods. In addition, warfarin use portends a significant risk of bleeding. For these reasons, warfarin is frequently not prescribed to persons for whom the drug would provide a clear benefit. Over the past decade, attempts have been made to develop drugs that are at least as safe and effective as warfarin for the treatment of atrial fibrillation that do not require monitoring nor have as many interactions. Initial studies of compounds in this regard ultimately failed due to safety concerns, but over the past two years two novel agents have been approved by the United States Food and Drug Association for anticoagulation in non-valvular atrial fibrillation, another drug is under review, and additional compounds are being studied. This article will review the use of warfarin and these new agents in the treatment of non-valvular atrial fibrillation.

Atrial Arrhythmias in Astronauts. Summary of a NASA Summit

Science.gov (United States)

Barr, Yael; Watkins, Sharmila; Polk, J. D.

2011-01-01

This slide presentation reviews the findings of a panel of heart experts brought together to study if atrial arrhythmias more prevalent in astronauts, and potential risk factors that may predispose astronauts to atrial arrhythmias. The objective of the panel was to solicit expert opinion on screening, diagnosis, and treatment options, identify gaps in knowledge, and propose relevant research initiatives. While Atrial Arrhythmias occur in approximately the same percents in astronauts as in the general population, they seem to occur at younger ages in astronauts. Several reasons for this predisposition were given: gender, hypertension, endurance training, and triggering events. Potential Space Flight-Related Risk factors that may play a role in precipitating lone atrial fibrillation were reviewed. There appears to be no evidence that any variable of the space flight environment increases the likelihood of developing atrial arrhythmias during space flight.

Assessment of non-invasive time and frequency atrial fibrillation organization markers with unipolar atrial electrograms

International Nuclear Information System (INIS)

Alcaraz, Raúl; Hornero, Fernando; Rieta, José J

2011-01-01

The standard electrocardiogram (ECG) is the most common non-invasive way to study atrial fibrillation (AF). In this respect, previous works have shown that the surface lead V 1 reflects mainly the dominant atrial frequency (DAF) of the right atrium (RA), which has been widely used to study AF. In a similar way, AF organization and fibrillatory (f) wave amplitude are two recently proposed non-invasive AF markers. These markers need to be validated with invasive recordings in order to assess their capability to reliably reflect the internal fibrillatory activity dynamics. In this work, these two non-invasive metrics have been compared with similar measures recorded from two unipolar atrial electrograms (AEGs). For both ECG and AEG signals, AF organization has been computed by applying a nonlinear regularity index, such as sample entropy (SampEn), to the atrial activity (AA) and to its fundamental waveform, defined as the main atrial wave (MAW). The surface and epicardial f wave amplitude has been estimated through their mean power. Results obtained for 38 patients showed statistically significant correlations between the values measured from surface and invasive recordings, thus corroborating the usefulness of the aforesaid markers in the non-invasive study of AF. Precisely, for AF organization computed from the MAW, the correlation coefficients between surface and both AEGs were R = 0.926 (p < 0.001) and R = 0.932 (p < 0.001). For f wave amplitude, slightly lower significant relationships were noticed, the correlation coefficients being R = 0.765 (p < 0.001) and R = 0.842 (p < 0.001). These outcomes together with interesting linear relationships found among the parameters suggest that AF regularity estimated via SampEn and f wave amplitude can non-invasively characterize the epicardial activity related to AF

Gene- and cell-based bio-artificial pacemaker: what basic and translational lessons have we learned?

Science.gov (United States)

Li, R A

2012-06-01

Normal rhythms originate in the sino-atrial node, a specialized cardiac tissue consisting of only a few thousands of nodal pacemaker cells. Malfunction of pacemaker cells due to diseases or aging leads to rhythm generation disorders (for example, bradycardias and sick-sinus syndrome (SSS)), which often necessitate the implantation of electronic pacemakers. Although effective, electronic devices are associated with such shortcomings as limited battery life, permanent implantation of leads, lead dislodging, the lack of autonomic responses and so on. Here, various gene- and cell-based approaches, with a particular emphasis placed on the use of pluripotent stem cells and the hyperpolarization-activated cyclic nucleotide-gated-encoded pacemaker gene family, that have been pursued in the past decade to reconstruct bio-artificial pacemakers as alternatives will be discussed in relation to the basic biological insights and translational regenerative potential.

Efeitos da estimulação temporária atrial direita na prevenção da fibrilação atrial no pós-operatório de revascularização do miocárdio com circulação extracorpórea Effect of temporary right atrial pacing in prevention of atrial fibrillation after coronary artery bypass graft surgery

Directory of Open Access Journals (Sweden)

Vicente Avila Neto

2007-09-01

Full Text Available OBJETIVO: Avaliar os efeitos da estimulação atrial direita temporária na prevenção da fibrilação atrial no pósoperatório de revascularização do miocárdio com circulação extracorpórea e identificar os fatores de risco para o aparecimento dessa arritmia. MÉTODO: Estudamos 160 pacientes que, ao término da cirurgia de revascularização miocárdica, submeteram-se ao implante de eletrodos epicárdicos na parede lateral do átrio direito e foram randomizados em grupos não-estimulado (NE e grupo com estímulo atrial direito (AD. O ritmo cardíaco foi monitorizado durante as 72 horas seguintes ao término da operação e as variáveis estudadas foram: a incidência de fibrilação atrial, os fatores de risco pré, intra e pós-operatórios para o seu aparecimento e eventos pósoperatórios. Resultados: Foram detectados 21 (13,1% episódios de fibrilação atrial, sendo 20 no grupo NE e um no grupo submetido à estimulação do átrio direito (AD. O risco relativo para o desenvolvimento de fibrilação atrial foi de 0,18 (IC 95%= 0,05-0,60 para o grupo AD quando comparado ao grupo NE. A regressão logística identificou que as variáveis idade mais jovem, uso de beta-bloqueador no pré-operatório e presença da estimulação atrial direita estiveram associadas a uma menor razão de chances (odds ratio para o surgimento de fibrilação atrial no pós-operatório. CONCLUSÕES: A estimulação atrial direita temporária reduziu a incidência de fibrilação atrial pós-operatória. A idade avançada e a não estimulação atrial foram fatores preditivos independentes para a ocorrência dessa arritmia.OBJECTIVE: To evaluated the effects of temporary atrial pacing to prevent the atrial fibrillation after coronary artery bypass graft surgery and the risk factors to the occurrence of this arrhytmia. METHODS: We have studied 160 patients who, at the end of coronary artery bypass graft surgery, were submitted to epicardial electrode

Treatment Guidelines of Atrial Fibrillation (AFib or AF)

Science.gov (United States)

... Artery Disease Venous Thromboembolism Aortic Aneurysm More Treatment Guidelines of Atrial Fibrillation (AFib or AF) Updated:Jun 28,2017 What are the treatment guidelines for atrial fibrillation? Medical guidelines are written by ...

Plain chest PA evaluation of left atrial thrombosis in mitral valvular disease

International Nuclear Information System (INIS)

Choo, Yeon Myung; Park, Jae Hyung; Han, Man Chung

1984-01-01

Conventional posteroanterior chest radiographs of 73 patients with mitral valve disease who had had surgery were analyzed, and particular attention was directed to the absence of the convexity of the left lower mid cardiac border (left atrial segment) and to the relation with duration of illness, atrial fibrillation, pulmonary capillary wedge pressure (PCWP) as well as surgical findings. The results obtained are as follows: 1. The flatness or concavity of this segment, despite other evidence of left atrial enlargement, was observed in eleven (64.7%) of 17 patients who had left atrial thrombosis and in six (10.7%) of 56 patients who did not have thrombosis (false positive diagnosis). Six (35.5%) of the 17 patients who had left atrial thrombosis did not this findings on radiographs (false positive diagnosis). Six (35.3%) of the 17 patients who had left atrial thrombosis did not show this finding on radiographs (false positive diagnosis). Therefore, the accuracy in the diagnosis of thrombosis of left atrium wa 64.7% (eleven of seventeen) for patients who had thrombosis of left atrium. 2. The atrial fibrillation was observed in sixteen (94.1%)of 17 patients who had left atrial thrombosis. So, correlation between the presence of left atrial thrombosis and atrial fibrillation wa evident. But there was no correlation between the duration of illness of the PCWP of patients and the presence of left atrial thrombosis.

Plain chest PA evaluation of left atrial thrombosis in mitral valvular disease

Energy Technology Data Exchange (ETDEWEB)

Choo, Yeon Myung; Park, Jae Hyung; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1984-09-15

Conventional posteroanterior chest radiographs of 73 patients with mitral valve disease who had had surgery were analyzed, and particular attention was directed to the absence of the convexity of the left lower mid cardiac border (left atrial segment) and to the relation with duration of illness, atrial fibrillation, pulmonary capillary wedge pressure (PCWP) as well as surgical findings. The results obtained are as follows: 1. The flatness or concavity of this segment, despite other evidence of left atrial enlargement, was observed in eleven (64.7%) of 17 patients who had left atrial thrombosis and in six (10.7%) of 56 patients who did not have thrombosis (false positive diagnosis). Six (35.5%) of the 17 patients who had left atrial thrombosis did not this findings on radiographs (false positive diagnosis). Six (35.3%) of the 17 patients who had left atrial thrombosis did not show this finding on radiographs (false positive diagnosis). Therefore, the accuracy in the diagnosis of thrombosis of left atrium wa 64.7% (eleven of seventeen) for patients who had thrombosis of left atrium. 2. The atrial fibrillation was observed in sixteen (94.1%)of 17 patients who had left atrial thrombosis. So, correlation between the presence of left atrial thrombosis and atrial fibrillation wa evident. But there was no correlation between the duration of illness of the PCWP of patients and the presence of left atrial thrombosis.

Analysis of brain natriuretic peptide in 30 patients with atrial fibrillation

International Nuclear Information System (INIS)

Jin Qiang; Lu Jianghui; Li Weipeng; Yuan Yuan; Sun Weili

2009-01-01

To investigate the relationship between atrial fibrillation and brain natriuretic peptide (BNP), plasma levels of BNP in 30 patients with atrial fibrillation and 30 health controls were assayed and compared. The results showed that plasma levels of BNP in patients with atrial fibrillation were significantly higher than those of health controls (P<0.05). When the patients with atrial fibrillation were restored sinus rhythm, the concentration of BNP decreased significantly (P<0.05). BNP was a sensitive marker of cardiac dysfunction, and BNP was positively correlated with atrial fibrillation. (authors)

Meta-analysis identifies six new susceptibility loci for atrial fibrillation

NARCIS (Netherlands)

Ellinor, Patrick T; Lunetta, Kathryn L; Albert, Christine M; Glazer, Nicole L; Ritchie, Marylyn D; Smith, Albert V; Arking, Dan E; Müller-Nurasyid, Martina; Krijthe, Bouwe P; Lubitz, Steven A; Bis, Joshua C; Chung, Mina K; Dörr, Marcus; Ozaki, Kouichi; Roberts, Jason D; Smith, J Gustav; Pfeufer, Arne; Sinner, Moritz F; Lohman, Kurt; Ding, Jingzhong; Smith, Nicholas L; Smith, Jonathan D; Rienstra, Michiel; Rice, Kenneth M; Van Wagoner, David R; Magnani, Jared W; Wakili, Reza; Clauss, Sebastian; Rotter, Jerome I; Steinbeck, Gerhard; Launer, Lenore J; Davies, Robert W; Borkovich, Matthew; Harris, Tamara B; Lin, Honghuang; Völker, Uwe; Völzke, Henry; Milan, David J; Hofman, Albert; Boerwinkle, Eric; Chen, Lin Y; Soliman, Elsayed Z; Voight, Benjamin F; Li, Guo; Chakravarti, Aravinda; Kubo, Michiaki; Tedrow, Usha B; Rose, Lynda M; Ridker, Paul M; Conen, David; Tsunoda, Tatsuhiko; Furukawa, Tetsushi; Sotoodehnia, Nona; Xu, Siyan; Kamatani, Naoyuki; Levy, Daniel; Nakamura, Yusuke; Parvez, Babar; Mahida, Saagar; Furie, Karen L; Rosand, Jonathan; Muhammad, Raafia; Psaty, Bruce M; Meitinger, Thomas; Perz, Siegfried; Wichmann, H-Erich; Witteman, Jacqueline C M; Kao, W H Linda; Kathiresan, Sekar; Roden, Dan M; Uitterlinden, Andre G; Rivadeneira, Fernando; McKnight, Barbara; Sjögren, Marketa; Newman, Anne B; Liu, Yongmei; Gollob, Michael H; Melander, Olle; Tanaka, Toshihiro; Stricker, Bruno H Ch; Felix, Stephan B; Alonso, Alvaro; Darbar, Dawood; Barnard, John; Chasman, Daniel I; Heckbert, Susan R; Benjamin, Emelia J; Gudnason, Vilmundur; Kääb, Stefan

Atrial fibrillation is a highly prevalent arrhythmia and a major risk factor for stroke, heart failure and death. We conducted a genome-wide association study (GWAS) in individuals of European ancestry, including 6,707 with and 52,426 without atrial fibrillation. Six new atrial fibrillation

The β3 Adrenergic Receptor Agonist BRL37344 Exacerbates Atrial Structural Remodeling Through iNOS Uncoupling in Canine Models of Atrial Fibrillation.

Science.gov (United States)

Wang, Xiaobing; Wang, Ruifeng; Liu, Guangzhong; Dong, Jingmei; Zhao, Guanqi; Tian, Jingpu; Sun, Jiayu; Jia, Xiuyue; Wei, Lin; Wang, Yuping; Li, Weimin

2016-01-01

The role of the β3-adrenergic receptor (β3-AR) agonist BRL37344 in atrial fibrillation (AF) structural remodeling and the underlying mechanisms as a therapeutic target were investigated. Four groups of dogs were evaluated: sham, pacing, β3-AR agonist BRL37344 (β3-AGO), and β3-AR antagonist L748337 (β3-ANT) groups. Dogs in the pacing, β3-AGO and β3-ANT groups were subjected to rapid atrial pacing for four weeks. Atrial structure and function, AF inducibility and duration, atrial myocyte apoptosis and interstitial fibrosis were assessed. Atrial superoxide anions were evaluated by fluorescence microscopy and colorimetric assays. Cardiac nitrate+nitrite levels were used to assess nitric oxide (NO) production. Protein and mRNA expression of β3-AR, neuronal NO synthase (nNOS), inducible NO synthase (iNOS), endothelial NO synthase (eNOS) and guanosine triphosphate cyclohydrolase-1 (GCH-1) as well as tetrahydrobiopterin (BH4) levels were measured. β3-AR was up-regulated in AF. Stimulation of β3-AR significantly increased atrial myocyte apoptosis, fibrosis and atrial dilatation, resulting in increased AF induction and prolonged duration. These effects were attenuated by β3-ANT. Moreover, β3-AGO reduced BH4 and NO production and increased superoxide production, which was inhibited by the specific iNOS inhibitor, 1400w β3-AGO also increased iNOS but decreased eNOS and had no effect on nNOS expression in AF. β3-AR stimulation resulted in atrial structural remodeling by increasing iNOS uncoupling and related oxidative stress. β3-AR up-regulation and iNOS uncoupling might be underlying AF therapeutic targets. © 2016 The Author(s) Published by S. Karger AG, Basel.

Giant right atrial myxoma: characterization with cardiac magnetic resonance imaging.

LENUS (Irish Health Repository)

Ridge, Carole A

2012-02-01

A 53-year-old woman presented to the emergency department with a 2-week history of dyspnoea and chest pain. Computed tomography pulmonary angiography was performed to exclude acute pulmonary embolism (PE). This demonstrated a large right atrial mass and no evidence of PE. Transthoracic echocardiography followed by cardiac magnetic resonance imaging confirmed a mobile right atrial mass. Surgical resection was then performed confirming a giant right atrial myxoma. We describe the typical clinical, radiologic, and pathologic features of right atrial myxoma.

Atrial fibrillation detection and R-wave synchronization by Metrix implantable atrial defibrillator - Implications for long-term efficacy and safety

NARCIS (Netherlands)

Tse, HF; Lau, CP; Sra, JS; Crijns, HJGM; Edvardsson, N; Kacet, S; Wyse, DG

1999-01-01

Background-The long-term efficacy of atrial fibrillation (AF) detection and R-wave synchronization are critical safety requirements for the development of an implantable atrial defibrillator (LAD) for treatment of AF. Methods and Results The long-term efficacy of the Metrix IAD for AF detection and

Atrial flutter with spontaneous 1:1 atrioventricular conduction in adults: an uncommon but frequently missed cause for syncope/presyncope.

Science.gov (United States)

Turitto, Gioia; Akhrass, Philippe; Leonardi, Marino; Saponieri, Cesare; Sette, Antonella; El-Sherif, Nabil

2009-01-01

To compare patients with atrial flutter (AFl) and 1:1 atrioventricular conduction (AVC) with patients with AFl and higher AVC. The characteristics of 19 patients with AFl and 1:1 AVC (group A) were compared with those of 116 consecutive patients with AFl and 2:1 AVC or higher degree AV block (group B). Age, gender, and left ventricular function were similar in the two groups. In group A versus group B, more patients had no structural heart disease (42% vs 17%, P AVC or vice versa was associated with small but definite changes in AFl CL, which showed larger variations in response to sympathetic stimulation. In group A patients who were studied off drugs, the atrial-His interval was not different from group B, but maximal atrial pacing rate with 1:1 AVC was faster. In group A, five patients were misdiagnosed as ventricular tachyarrhythmias, and three with a defibrillator received inappropriate shocks. Four patients had ablation of AVC and six had ablation of AFl circuit. The main difference between groups A and B may be an inherent capacity of the AV node for faster conduction, especially in response to increased sympathetic tone. The latter affects not only AVC but also the AFl CL. One should be aware of the different presentations of AFl with 1:1 AVC to avoid misdiagnosis/mismanagement and to consider the diagnosis in patients with narrow or wide QRS tachycardia and rates above 220/min.

Hyperthyroidism and atrial myxoma--an intriguing cardio-endocrine association.

Science.gov (United States)

Kumar, Gautam; Chow, John T; Klarich, Kyle W; Dean, Diana S

2007-12-01

A 65-year-old woman presented with dyspnea and bilateral leg edema for 1 week, worsening fatigue for 1 month, and a 7-lb weight loss over the last summer. She was clinically and biochemically hyperthyroid. Echocardiography revealed a left atrial myxoma measuring 6.2 x 3.3 cm protruding into the mitral orifice and left ventricle during diastole. She was treated for Graves' disease with Iodine-131. Six weeks later, her left atrial myxoma measuring 10.1 x 6.2 x 2.4 cm was resected. She became euthyroid before surgery and then biochemically hypothyroid 6 weeks after radioiodine treatment, for which she subsequently required thyroxine replacement. Atrial myxomas are the most common primary cardiac neoplasms. At least 5% to 10% can be attributed to Carney's complex. More than two-thirds of patients with Carney's complex develop one or more cardiac myxomas. Although atrial myxomas in Carney's complex are histologically indistinguishable from the sporadic form, their clinical presentation and course is distinct. This is the first case of newly diagnosed Graves' disease that has been reported in association with an atrial myxoma. The features discussed in this article help differentiate between syndromic and sporadic atrial myxomas.

Total plasma proANP increases with atrial dilatation in horses

DEFF Research Database (Denmark)

Van Der Vekens, N; Hunter, I; Timm, A

2015-01-01

ANP product in plasma has proven to be successful in human medicine, but has never been used in horses. The aims were to establish an equine proANP reference interval by measurement of the total proANP product using PIA and to examine the proANP concentrations in horses with atrial dilatation. Sample...... stability was studied by comparison of storage at -80°C and -20°C. Plasma samples were obtained from 23 healthy horses, 12 horses with moderate or severe valvular regurgitation without atrial dilatation and 42 horses with valvular regurgitation and atrial dilatation. The proANP concentration...... was significantly (Phorses with atrial dilatation (761.4 (442.1-1859.1) pmol/l) than in healthy horses (491.6 (429.5-765.9) pmol/l; Phorses with cardiac disease but without atrial dilatation (544.4 (457.0-677.6) pmol/l). A cut-off value (573.8 pmol/l) for detection of atrial dilatation...

Left Atrial Decompression by Percutaneous Left Atrial Venting Cannula Insertion during Venoarterial Extracorporeal Membrane Oxygenation Support

Directory of Open Access Journals (Sweden)

Ha Eun Kim

2016-06-01

Full Text Available Patients with venoarterial extracorporeal membrane oxygenation (ECMO frequently suffer from pulmonary edema due to left ventricular dysfunction that accompanies left heart dilatation, which is caused by left atrial hypertension. The problem can be resolved by left atrium (LA decompression. We performed a successful percutaneous LA decompression with an atrial septostomy and placement of an LA venting cannula in a 38-month-old child treated with venoarterial ECMO for acute myocarditis.

Node cookbook

CERN Document Server

Clements, David Mark

2014-01-01

In Node Cookbook Second Edition, each chapter focuses on a different aspect of working with Node. Following a Cookbook structure, the recipes are written in an easy-to-understand language. Readers will find it easier to grasp even the complex recipes which are backed by lots of illustrations, tips, and hints.If you have some knowledge of JavaScript and want to build fast, efficient, scalable client-server solutions, then Node Cookbook Second Edition is for you. Knowledge of Node will be an advantage but is not required. Experienced users of Node will be able to improve their skills.

Insights into new-onset atrial fibrillation following open heart surgery and implications for type II atrial flutter.

Science.gov (United States)

Sadrpour, Shervin A; Srinivasan, Deepa; Bhimani, Ashish A; Lee, Seungyup; Ryu, Kyungmoo; Cakulev, Ivan; Khrestian, Celeen M; Markowitz, Alan H; Waldo, Albert L; Sahadevan, Jayakumar

2015-12-01

Postoperative atrial fibrillation (POAF), new-onset AF after open heart surgery (OHS), is thought to be related to pericarditis. Based on AF studies in the canine sterile pericarditis model, we hypothesized that POAF in patients after OHS may be associated with a rapid, regular rhythm in the left atrium (LA), suggestive of an LA driver maintaining AF. The aim of this study was to test the hypothesis that in patients with POAF, atrial electrograms (AEGs) recorded from at least one of the two carefully selected LA sites would manifest a rapid, regular rhythm with AEGs of short cycle length (CL) and constant morphology, but a selected right atrial (RA) site would manifest AEGs with irregular CLs and variable morphology. In 44 patients undergoing OHS, AEGs recorded from the epicardial surface of the RA, the LA portion of Bachmann's bundle, and the posterior LA during sustained AF were analysed for regularity of CL and morphology. Sustained AF occurred in 15 of 44 patients. Atrial electrograms were recorded in 11 of 15 patients; 8 of 11 had rapid, regular activation with constant morphology recorded from at least one LA site; no regular AEG sites were present in 3 of 11 patients. Atrial electrograms recorded during sustained POAF frequently demonstrated rapid, regular activation in at least one LA site, consistent with a driver maintaining AF. Published by Oxford University Press on behalf of the European Society of Cardiology 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Slow conduction in the border zones of patchy fibrosis stabilises the drivers for atrial fibrillation: Insights from multi-scale human atrial modelling

Directory of Open Access Journals (Sweden)

Ross Morgan

2016-10-01

Full Text Available Introduction. The genesis of atrial fibrillation (AF and success of AF ablation therapy have been strongly linked with atrial fibrosis. Increasing evidence suggests that patient-specific distributions of fibrosis may determine the locations of electrical drivers (rotors sustaining AF, but the underlying mechanisms are incompletely understood. This study aims to elucidate a missing mechanistic link between patient-specific fibrosis distributions and AF drivers. Methods. 3D atrial models integrated human atrial geometry, rule-based fibre orientation, region-specific electrophysiology and AF-induced ionic remodelling. A novel detailed model for an atrial fibroblast was developed, and effects of myocyte-fibroblast (M-F coupling were explored at single-cell, 1D tissue and 3D atria levels. Left atrial LGE MRI datasets from 3 chronic AF patients were segmented to provide the patient-specific distributions of fibrosis. The data was non-linearly registered and mapped to the 3D atria model. Six distinctive fibrosis levels (0 – healthy tissue, 5 – dense fibrosis were identified based on LGE MRI intensity and modelled as progressively increasing M-F coupling and decreasing atrial tissue coupling. Uniform 3D atrial model with diffuse (level 2 fibrosis was considered for comparison.Results. In single cells and tissue, the largest effect of atrial M-F coupling was on the myocyte resting membrane potential, leading to partial inactivation of sodium current and reduction of conduction velocity (CV. In the 3D atria, further to the M-F coupling, effects of fibrosis on tissue coupling greatly reduce atrial CV. AF was initiated by fast pacing in each 3D model with either uniform or patient-specific fibrosis. High variation in fibrosis distributions between the models resulted in varying complexity of AF, with several drivers emerging. In the diffuse fibrosis models, waves randomly meandered through the atria, whereas in each the patient-specific models, rotors

Controlling parasympathetic regulation of heart rate: a gatekeeperrole for RGS proteins in the sinoatrial node

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Alexandra eMighiu

2012-06-01

Full Text Available Neurotransmitters released from sympathetic and parasympathetic nerve terminals in the SAN exert their effects via G-protein-coupled receptors. Integration of these different G-protein signals within pacemaker cells of the sinoatrial node (SAN is critical for proper regulation of heart rate and function. For example, excessive parasympathetic signaling can be associated with sinus node dysfunction and supraventricular arrhythmias. Our previous work has shown that one member of the regulator of G-protein signaling (RGS protein family, RGS4, is highly and selectively expressed in pacemaker cells of the SAN. Consistent with its role as an inhibitor of parasympathetic signaling, RGS4-knockout mice have reduced basal heart rates and enhanced negative chronotropic responses to parasympathetic agonists. Moreover, RGS4 appears to be an important part of SA nodal myocyte signaling pathways that mediate G protein-coupled inwardly-rectifying potassium channel (GIRK channel activation/deactivation and desensitization. Since RGS4 acts immediately downstream of M2 muscarinic receptors, it is tempting to speculate that RGS4 functions as a master regulator of parasympathetic signaling upstream of GIRKs, HCNs and L-type Ca2+ channels in the SAN. Thus, loss of RGS4 function may lead to increased susceptibility to conditions associated with increased parasympathetic signaling, including bradyarrhythmia, sinus node dysfunction, and atrial fibrillation.

Pulmonary artery-to-left atrial fistula discovered after the closure of atrial septal defect: A rare clinical scenario

Directory of Open Access Journals (Sweden)

Akshay Chauhan

2018-01-01

Full Text Available A case of the right pulmonary artery-to- left atrial fistula with atrial septal defect (ASD is presented. The fistula was detected after the patient developed desaturation following surgical closure of the ASD. It was managed with a transcatheter (trans-RPA route closure of the fistula using a 12-mm Amplatzer ventricular septal defect closure device.

Left-to-Right Atrial Inward Rectifier Potassium Current Gradients in Patients With Paroxysmal Versus Chronic Atrial Fibrillation

Science.gov (United States)

Voigt, Niels; Trausch, Anne; Knaut, Michael; Matschke, Klaus; Varró, András; Van Wagoner, David R.; Nattel, Stanley; Ravens, Ursula; Dobrev, Dobromir

2018-01-01

Background Recent evidence suggests that atrial fibrillation (AF) is maintained by high-frequency reentrant sources with a left-to-right–dominant frequency gradient, particularly in patients with paroxysmal AF (pAF). Unequal left-to-right distribution of inward rectifier K+ currents has been suggested to underlie this dominant frequency gradient, but this hypothesis has never been tested in humans. Methods and Results Currents were measured with whole-cell voltage-clamp in cardiomyocytes from right atrial (RA) and left (LA) atrial appendages of patients in sinus rhythm (SR) and patients with AF undergoing cardiac surgery. Western blot was used to quantify protein expression of IK1 (Kir2.1 and Kir2.3) and IK,ACh (Kir3.1 and Kir3.4) subunits. Basal current was ≈2-fold larger in chronic AF (cAF) versus SR patients, without RA-LA differences. In pAF, basal current was ≈2-fold larger in LA versus RA, indicating a left-to-right atrial gradient. In both atria, Kir2.1 expression was ≈2-fold greater in cAF but comparable in pAF versus SR. Kir2.3 levels were unchanged in cAF and RA-pAF but showed a 51% decrease in LA-pAF. In SR, carbachol-activated (2 μmol/L) IK,ACh was 70% larger in RA versus LA. This right-to-left atrial gradient was decreased in pAF and cAF caused by reduced IK,ACh in RA only. Similarly, in SR, Kir3.1 and Kir3.4 proteins were greater in RA versus LA and decreased in RA of pAF and cAF. Kir3.1 and Kir3.4 expression was unchanged in LA of pAF and cAF. Conclusions Our results support the hypothesis that a left-to-right gradient in inward rectifier background current contributes to high-frequency sources in LA that maintain pAF. These findings have potentially important implications for development of atrial-selective therapeutic approaches. PMID:20657029

Exploration and Practice of Green Building Management in Sino-Singapore Tianjin Eco-City

Institute of Scientific and Technical Information of China (English)

Sun; Xiaofeng; Song; Kun; Liu; Jinxin

2016-01-01

This paper summarizes the current development status of green building management in China, and analyzes the problems existing in its present management pattern. It fi rstly introduces the background, procedures and achievements gained during the green building practice in the Sino-Singapore Tianjin Eco-City, expounds the principles and methods of the establishment of the green building management system in this Tianjin Eco-City, and then focuses on practical experience and specifi c measures in separate parts of green building management system in the Tianjin EcoCity, which is constituted by laws, regulations and policies, technical standards, management process, product access, etc. Through exploration and practice, it took 8 years for the Sino-Singapore Tianjin Eco-City to preliminarily establish a set of management systems which were suited to its own characteristics. By introduction of the management system, this paper aims to provide reference for other cities to carry out green building practice and improve the quality of green buildings in China.

3rd Sino-German Conference “Underground Storage of CO2 and Energy”

CERN Document Server

Xie, Heping; Were, Patrick

2013-01-01

Anthropogenic greenhouse gas emissions, energy security and sustainability are three of the greatest contemporary global challenges today. This year the Sino-German Cooperation Group “Underground Storage of CO2 and Energy”, is meeting on the 21-23 May 2013 for the second time in Goslar, Germany, to convene its 3rd Sino-German conference on the theme “Clean Energy Systems in the Subsurface: Production, Storage and Conversion”.   This volume is a collection of diverse quality scientific works from different perspectives elucidating on the current developments in CO2 geologic sequestration research to reduce greenhouse emissions including measures to monitor surface leakage, groundwater quality and the integrity of caprock, while ensuring a sufficient supply of clean energy. The contributions herein have been structured into 6 major thematic research themes: Integrated Energy and Environmental Utilization of Geo-reservoirs: Law, Risk Management & Monitoring CO2 for Enhanced Gas and Oil Recovery, Coa...

Aorto-right atrial fistula after ascending aortic replacement or aortic value replacement

International Nuclear Information System (INIS)

Zhi Aihua; Dai Ruping; Jiang Shiliang; Lu Bin

2012-01-01

Objective: To evaluate the CT features of aorto-right atrial fistula after aortic valve replacement (AVR) or ascending aortic replacement. Methods: Eighty-seven patients with aortic-right atrial fistula underwent CT after operation. The CT features were retrospectively analyzed. Fistula was measured according to maximum width of the shunt. Results: Aorto-right atrial fistula was detected in 87 patients after aortic valve replacement or ascending aortic replacement by CT scan. Among them, 25 patients were diagnosed as mild aorto-right atrial fistula, 47 patients as moderate, and 15 patients as severe. Thirty-seven patients underwent follow-up CT.Among them, 10 patients with mild to moderate aorto-right atrial fistula were considered to have complete regression, 8 patients with mild aorto-right atrial fistula considered to have incomplete regression, 14 patients with mild to moderate aorto-right atrial fistula considered to have stable condition, and 5 patients with moderate aorto-right atrial fistula considered to have progression at the 3-month follow-up. Conclusion: CT is a useful tool for defining aorto-right atrial fistula after AVR or ascending aortic replacement and for evaluating it in follow-up. (authors)

Three-dimensional atrial wall thickness maps to inform catheter ablation procedures for atrial fibrillation.

Science.gov (United States)

Bishop, Martin; Rajani, Ronak; Plank, Gernot; Gaddum, Nicholas; Carr-White, Gerry; Wright, Matt; O'Neill, Mark; Niederer, Steven

2016-03-01

Transmural lesion formation is critical to success in atrial fibrillation ablation and is dependent on left atrial wall thickness (LAWT). Pre- and peri-procedural planning may benefit from LAWT measurements. To calculate the LAWT, the Laplace equation was solved over a finite element mesh of the left atrium derived from the segmented computed tomographic angiography (CTA) dataset. Local LAWT was then calculated from the length of field lines derived from the Laplace solution that spanned the wall from the endocardium or epicardium. The method was validated on an atrium phantom and retrospectively applied to 10 patients who underwent routine coronary CTA for standard clinical indications at our institute. The Laplace wall thickness algorithm was validated on the left atrium phantom. Wall thickness measurements had errors of atrial wall thickness measurements were performed on 10 patients. Successful comprehensive LAWT maps were generated in all patients from the coronary CTA images. Mean LAWT measurements ranged from 0.6 to 1.0 mm and showed significant inter and intra patient variability. Left atrial wall thickness can be measured robustly and efficiently across the whole left atrium using a solution of the Laplace equation over a finite element mesh of the left atrium. Further studies are indicated to determine whether the integration of LAWT maps into pre-existing 3D anatomical mapping systems may provide important anatomical information for guiding radiofrequency ablation. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

Molecular Mechanisms and New Treatment Paradigm for Atrial Fibrillation.

Science.gov (United States)

Sirish, Padmini; Li, Ning; Timofeyev, Valeriy; Zhang, Xiao-Dong; Wang, Lianguo; Yang, Jun; Lee, Kin Sing Stephen; Bettaieb, Ahmed; Ma, Sin Mei; Lee, Jeong Han; Su, Demetria; Lau, Victor C; Myers, Richard E; Lieu, Deborah K; López, Javier E; Young, J Nilas; Yamoah, Ebenezer N; Haj, Fawaz; Ripplinger, Crystal M; Hammock, Bruce D; Chiamvimonvat, Nipavan

2016-05-01

Atrial fibrillation represents the most common arrhythmia leading to increased morbidity and mortality, yet, current treatment strategies have proven inadequate. Conventional treatment with antiarrhythmic drugs carries a high risk for proarrhythmias. The soluble epoxide hydrolase enzyme catalyzes the hydrolysis of anti-inflammatory epoxy fatty acids, including epoxyeicosatrienoic acids from arachidonic acid to the corresponding proinflammatory diols. Therefore, the goal of the study is to directly test the hypotheses that inhibition of the soluble epoxide hydrolase enzyme can result in an increase in the levels of epoxyeicosatrienoic acids, leading to the attenuation of atrial structural and electric remodeling and the prevention of atrial fibrillation. For the first time, we report findings that inhibition of soluble epoxide hydrolase reduces inflammation, oxidative stress, atrial structural, and electric remodeling. Treatment with soluble epoxide hydrolase inhibitor significantly reduces the activation of key inflammatory signaling molecules, including the transcription factor nuclear factor κ-light-chain-enhancer, mitogen-activated protein kinase, and transforming growth factor-β. This study provides insights into the underlying molecular mechanisms leading to atrial fibrillation by inflammation and represents a paradigm shift from conventional antiarrhythmic drugs, which block downstream events to a novel upstream therapeutic target by counteracting the inflammatory processes in atrial fibrillation. © 2016 American Heart Association, Inc.

Allocating resources between network nodes for providing a network node function

NARCIS (Netherlands)

Strijkers, R.J.; Meulenhoff, P.J.

2014-01-01

The invention provides a method wherein a first network node advertises available resources that a second network node may use to offload network node functions transparently to the first network node. Examples of the first network node are a client device (e.g. PC, notebook, tablet, smart phone), a

Recurrence of pulmonary vein conduction and atrial fibrillation after pulmonary vein isolation for atrial fibrillation

DEFF Research Database (Denmark)

Nilsson, Brian; Chen, Xu; Pehrson, Steen

2006-01-01

BACKGROUND: Both segmental ostial and circumferential extraostial pulmonary vein (PV) isolation have been proven effective in the treatment of atrial fibrillation (AF). However, the recurrence of AF and PV conduction after the 2 ablation strategies has never been compared in a randomized study...... isolation. Extraostial PV isolation was performed by encircling the paired left and right PVs, respectively, guided by an electroanatomic mapping system. RESULTS: A total of 84% of the patients had recurrent AF after the first PV isolation procedure, showing 72% with AF and 12% with organized left atrial...

Development of a transgenic goat model wih cardiac-specific overexpression of transforming growth factor - {beta} 1 to study the relationship between atrial fibrosis and atrial fibrillation

Science.gov (United States)

Studies on patients, large animal models and transgenic mouse models have shown a strong association of atrial fibrosis with atrial fibrillation (AF). However, it is unclear whether there is a causal relationship between atrial fibrosis and AF or whether these events appear as a result of independen...

Structural and functional characteristics of myocard in patients with different forms of atrial fibrillation

Directory of Open Access Journals (Sweden)

L. I. Vasilyeva

2015-02-01

Full Text Available Aim. To study structural and functional characteristics of myocard in patients with different forms of atrial fibrillation. Atrial fibrillation is the most prevalent arrhythmia in clinical practice. Atrial fibrillation is a progressive disease: the duration of paroxysms increases over time and paroxysmal atrial fibrillation transforms to persistent, the last one becomes refractory to pharmacological and electrical cardioversion in time and transforms to permanent. So assessment of myocardial remodeling in patients with persistent and permanent atrial fibrillation is very actual. Methods and results. According to the aim of the study 133 patients with persistent atrial fibrillation and 100 patients with permanent atrial fibrillation were included into the study. Echocardiographic parameters of left and right atria function were studied. Conclusion. It was found that patients with persistent and permanent atrial fibrillation are characterized with both left and right atrias remodeling. Remodeling of the atrias is less pronounced in patients with permanent atrial fibrillation in comparison with persistent atrial fibrillation patients and arrhythmia recurrence.

Atrial arrhythmia in ageing spontaneously hypertensive rats: unraveling the substrate in hypertension and ageing.

Directory of Open Access Journals (Sweden)

Dennis H Lau

Full Text Available BACKGROUND: Both ageing and hypertension are known risk factors for atrial fibrillation (AF although the pathophysiological contribution or interaction of the individual factors remains poorly understood. Here we aim to delineate the arrhythmogenic atrial substrate in mature spontaneously hypertensive rats (SHR. METHODS: SHR were studied at 12 and 15 months of age (n = 8 per group together with equal numbers of age-matched normotensive Wistar-Kyoto control rats (WKY. Electrophysiologic study was performed on superfused isolated right and left atrial preparations using a custom built high-density multiple-electrode array to determine effective refractory periods (ERP, atrial conduction and atrial arrhythmia inducibility. Tissue specimens were harvested for structural analysis. RESULTS: COMPARED TO WKY CONTROLS, THE SHR DEMONSTRATED: Higher systolic blood pressure (p<0.0001, bi-atrial enlargement (p<0.05, bi-ventricular hypertrophy (p<0.05, lower atrial ERP (p = 0.008, increased atrial conduction heterogeneity (p = 0.001 and increased atrial interstitial fibrosis (p = 0.006 & CD68-positive macrophages infiltration (p<0.0001. These changes resulted in higher atrial arrhythmia inducibility (p = 0.01 and longer induced AF episodes (p = 0.02 in 15-month old SHR. Ageing contributed to incremental bi-atrial hypertrophy (p<0.01 and atrial conduction heterogeneity (p<0.01 without affecting atrial ERP, fibrosis and arrhythmia inducibility. The limited effect of ageing on the atrial substrate may be secondary to the reduction in CD68-positive macrophages. CONCLUSIONS: Significant atrial electrical and structural remodeling is evident in the ageing spontaneously hypertensive rat atria. Concomitant hypertension appears to play a greater pathophysiological role than ageing despite their compounding effect on the atrial substrate. Inflammation is pathophysiologically linked to the pro-fibrotic changes in the hypertensive atria.

Cerebral Pulsatility Index Is Elevated in Patients with Elevated Right Atrial Pressure.

Science.gov (United States)

Lahiri, Shouri; Schlick, Konrad H; Padrick, Matthew M; Rinsky, Brenda; Gonzalez, Nestor; Jones, Heather; Mayer, Stephan A; Lyden, Patrick D

2018-01-01

Extracerebral venous congestion can precipitate intracranial hypertension due to obstruction of cerebral blood outflow. Conditions that increase right atrial pressure, such as hypervolemia, are thought to increase resistance to jugular venous outflow and contribute to cerebro-venous congestion. Cerebral pulsatility index (CPI) is considered a surrogate marker of distal cerebrovascular resistance and is elevated with intracranial hypertension. Thus, we sought to test the hypothesis that elevated right atrial pressure is associated with increased CPI compared to normal right atrial pressure. We retrospectively reviewed 61 consecutive patients with subarachnoid hemorrhage. We calculated CPI from transcranial Doppler studies and correlated these with echocardiographic measures of right atrial pressure. CPIs were compared from patients with elevated and normal right atrial pressure. There was a significant difference between CPI obtained from all patients with elevated right atrial pressure compared to those with normal right atrial pressure (P right and left hemispheric CPI from patients with both elevated and normal right atrial pressure. Patients with elevated right atrial pressure had significantly higher CPI compared to patients with normal right atrial pressure. These findings suggest that cerebro-venous congestion due to impaired jugular venous outflow may increase distal cerebrovascular resistance as measured by CPI. Since elevated CPI is associated with poor outcome in numerous neurological conditions, future studies are needed to elucidate the significance of these results in other populations. Copyright © 2017 by the American Society of Neuroimaging.

Risk of atrial fibrillation and stroke in rheumatoid arthritis

DEFF Research Database (Denmark)

Lindhardsen, Jesper; Ahlehoff, Ole; Gislason, Gunnar Hilmar

2012-01-01

To determine if patients with rheumatoid arthritis have increased risk of atrial fibrillation and stroke.......To determine if patients with rheumatoid arthritis have increased risk of atrial fibrillation and stroke....

Allocating resources between network nodes for providing a network node function

OpenAIRE

Strijkers, R.J.; Meulenhoff, P.J.

2014-01-01

The invention provides a method wherein a first network node advertises available resources that a second network node may use to offload network node functions transparently to the first network node. Examples of the first network node are a client device (e.g. PC, notebook, tablet, smart phone), a server (e.g. application server, a proxy server, cloud location, router). Examples of the second network node are an application server, a cloud location or a router. The available resources may b...

Percutaneous left atrial appendage occlusion for stroke prevention in atrial fibrillation

DEFF Research Database (Denmark)

De Backer, O; Arnous, S; Ihlemann, N

2014-01-01

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in clinical practice. One of its most devastating complications is the development of thromboembolism leading to fatal or disabling stroke. Oral anticoagulation (OAC, warfarin) is the standard treatment for strok...

Dabigatran versus warfarin in patients with atrial fibrillation

NARCIS (Netherlands)

Connolly, Stuart J.; Ezekowitz, Michael D.; Yusuf, Salim; Eikelboom, John; Oldgren, Jonas; Parekh, Amit; Pogue, Janice; Reilly, Paul A.; Themeles, Ellison; Varrone, Jeanne; Wang, Susan; Alings, Marco; Xavier, Denis; Zhu, Jun; Diaz, Rafael; Lewis, Basil S.; Darius, Harald; Diener, Hans-Christoph; Joyner, Campbell D.; Wallentin, Lars; Connolly, S. J.; Ezekowitz, M. D.; Yusuf, S.; Eikelboom, J.; Oldgren, J.; Parekh, A.; Reilly, P. A.; Themeles, E.; Varrone, J.; Wang, S.; Palmcrantz-Graf, E.; Haehl, M.; Wallentin, L.; Alings, A. M. W.; Amerena, J. V.; Avezum, A.; Baumgartner, I.; Brugada, J.; Budaj, A.; Caicedo, V.; Ceremuzynski, L.; Chen, J. H.; Commerford, P. J.; Dans, A. L.; Darius, H.; Di Pasquale, G.; Diaz, R.; Erol, C.; Ferreira, J.; Flaker, G. C.; Flather, M. D.; Franzosi, M. G.; Gamboa, R.; Golitsyn, S. P.; Gonzalez Hermosillo, J. A.; Halon, D.; Heidbuchel, H.; Hohnloser, S. H.; Hori, M.; Huber, K.; Jansky, P.; Kamensky, G.; Keltai, M.; Kim, S.; Lau, C. P.; Le Heuzey, J. Y. F.; Lewis, B. S.; Liu, L. S.; Nanas, J.; Razali, O.; Pais, P. S.; Parkhomenko, A. N.; Pedersen, K. E.; Piegas, L. S.; Raev, D.; Simmers, T. A.; Smith, P. J.; Talajic, M.; Tan, R. S.; Tanomsup, S.; Toivonen, L.; Vinereanu, D.; Xavier, D.; Zhu, J.; Diener, H. C.; Joyner, C. D.; Diehl, A.; Ford, G.; Robinson, M.; Silva, J.; Sleight, P.; Wyse, D. G.; Collier, J.; de Mets, D.; Hirsh, J.; Lesaffre, E.; Ryden, L.; Sandercock, P.; Anastasiou-Nana, M. I.; Andersen, G.; Annex, B. H.; Atra, M.; Bornstein, N. M.; Boysen, G.; Brouwers, P. J. A. M.; Buerke, M.; Burrell, L. M.; Chan, Y. K.; Chen, W. H.; Cheung, R. T. F.; Divakaramenon, S.; Donnan, G. A.; Duray, G. Z.; Dvorakova, H.; Fiedler, J.; Gardinale, E.; Gates, P. C.; Goshev, E. G.; Goto, S.; Gross, B.; Guimaraes, H. P.; Gulkevych, O.; Haberl, R. L.; Hankey, G.; Hartikainen, J.; Healey, J.; Iliesiu, A. M.; Irkin, O.; Jaxa-Chamiec, T.; Jolly, S.; Kaste, K. A. M.; Kies, B.; Kostov, K. D.; Kristensen, K. S.; Labovitz, A. J.; Lassila, R. P. T.; Lee, K. L. F.; Lutay, Y. M.; Magloire, P.; Mak, K. H.; Meijer, A.; Mihov, L.; Morillo, C. A.; Morillo, L. E.; Nair, G. M.; Norrving, B.; Ntalianis, A.; Ntsekhe, M.; Olah, L.; Pasco, P. M. D.; Peeters, A.; Perovic, V.; Petrov, I.; Pizzolato, G.; Rafti, F.; Rey, N. R.; Ribas, S.; Rokoss, M.; Sarembock, I. J.; Sheth, T.; Shuaib, A.; Sitkei, E.; Sorokin, E.; Srámek, M.; Strozynska, E.; Tanne, D.; Thijs, V. N. S.; Tomek, A.; Turazza, F.; Vanhooren, G.; Vizel, S. A.; Vos, J.; Wahlgren, N.; Weachter, R.; Zaborska, B.; Zaborski, J.; Zimlichman, R.; Cong, J.; Fendt, K.; Muldoon, S.; Bajkor, S.; Grinvalds, A.; Malvaso, M.; Pogue, J.; Simek, K.; Yang, S.; Alzogaray, M. F.; Bono, J. O.; Caccavo, A.; Cartasegna, L.; Casali, W. P.; Cuello, J. L.; Cuneo, C. A.; Elizari, M. V.; Fernandez, A. A.; Ferrari, A. E.; Gabito, A. J.; Goicoechea, R. F.; Gorosito, V. M.; Hirschson, A.; Hominal, M. A.; Hrabar, A. D.; Liberman, A.; Mackinnon, I. J.; Manzano, R. D.; Muratore, C. A.; Nemi, S. A.; Rodriguez, M. A.; Sanchez, A. S.; Secchi, J.; Vogel, D. R.; Colquhoun, D. M.; Crimmins, D. S.; Dart, A. M.; Davis, S. M.; Hand, P. J.; Kubler, P. A.; Lehman, R. G.; McBain, G.; Morrison, H. C.; New, G.; Singh, B. B.; Spence, C. Z.; Waites, J. H.; Auer, J.; Doweik, L.; Freihoff, F.; Gaul, G.; Gazo, F.; Geiger, H.; Giacomini, G.; Huber, G. W.; Jukic, I.; Lamm, G.; Niessner, H.; Podczeck, A.; Schuh, J.; Siostrzonek, P.; Steger, C.; Vogel, B.; Watzak, R.; Weber, H. S.; Weihs, W.; Blankoff, I.; Boland, J. L.; Brike, C.; Carlier, M.; Cools, F.; de Meester, A.; de Raedt, H. J.; de Wolf, L.; Dhooghe, G. M.; Dilling-Boer, D.; Elshot, S. R.; Fasseaux, S.; Goethals, M.; Goethals, P.; Gurne, O.; Hellemans, S.; Ivan, B.; Jottrand, M.; Kersschot, I.; Lecoq, E.; Marcovitch, O.; Melon, D.; Miljoen, H.; Missault, L.; Pierard, L. A.; Provenier, F.; Rousseau, M. F.; Stockman, D.; Tran-Ngoc, E.; van Mieghem, W.; Vandekerckhove, Y.; Vandervoort, P.; Verrostte, J.; Vijgen, J.; Armaganijan, D.; Braga, C.; Braga, J. C. F.; Cipullo, R.; Cunha, C. L. P.; de Paola, A.; Delmonaco, M. I.; Guimaraes, F. V.; Herek, L.; Kerr Saraiva, J. F.; Maia, L. N.; Lorga, A. M.; Lorga-Filho, A. M.; Marino, R. L.; Melo, C. S.; Mouco, O. M.; Pereira, V. C.; Precoma, D. B.; Rabelo, W.; Rassi, S.; Rossi, P. R.; Rossi Neto, J. M.; Silva, F. M.; Vidotti, M. H.; Zimmermann, S. L.; Anev, E. D.; Balabanov, T. A.; Baldjiev, E. S.; Bogusheva, E. S.; Chaneva, M. A.; Filibev, I. G.; Gotcheva, N. N.; Goudev, A. R.; Gruev, I. T.; Guenova, D. T.; Kamenova, Z. A.; Manov, E. I.; Panov, I. A.; Parvanova, Z. I.; Pehlivanova, M. B.; Penchev, P. T.; Penkov, N. Y.; Radoslavov, A. L.; Ramshev, K. N.; Runev, N. M.; Sindzhielieva, M. N.; Spirova, D. A.; Tsanova, V. M.; Tzekova, M. L.; Yaramov, G. K.; Aggarwal, R.; Bakbak, A. I.; Bayly, K.; Berlingieri, J. C.; Blackburn, K.; Bobbie, C.; Booth, A. W.; Borts, D.; Bose, S.; Boucher, P.; Brown, K.; Burstein, J. M.; Butt, J. C.; Carlson, B. D.; Chetty, R.; Chiasson, J. D.; Constance, C.; Costi, P.; Coutu, B.; Deneufbourg, I.; Dion, D.; Dorian, P.; Douketis, J. D.; Farukh, S.; Filipchuk, N. G.; Fox, B. A.; Fox, H. I.; Gailey, C. B.; Gauthier, M.; Glanz, A.; Green, M. S.; Habot, J.; Hink, H.; Kearon, C.; Kouz, S.; Lai, C.; Lai, K.; Lalani, A. V.; Lam, A. S.; Lapointe, L. A.; Leather, R. A.; Ma, P. T. S.; MacKay, E.; Mangat, I.; Mansour, S.; Melton, E.; Mitchell, L. B.; Morris, A. L.; Nisker, W. A.; O'Donnell, M. J.; O'Hara, G.; Omichinski, L. M.; Pandey, A. S.; Parkash, R.; Pesant, Y.; Pilon, C.; Pistawka, K. J.; Powell, C. N.; Price, J. B.; Prieur, S.; Rebane, T. M.; Ricci, A. J.; Roberge, J.; Roy, M.; Sapp, J. L.; Savard, D.; Schulman, S.; Sehl, M. J.; Sestier, F.; Shandera, R.; Shu, D.; Sterns, L. D.; St-Hilaire, R.; Syan, G. S.; Talbot, P.; Teitelbaum, I.; Tytus, R. H.; Winkler, L.; Zadra, R.; Zidel, B. S.; Bai, X. J.; Gao, W.; Gao, X.; Guan, D. M.; He, Z. S.; Hua, Q.; Li, H.; Li, L.; Li, W. M.; Lu, G. P.; Lv, S.; Meng, K.; Niu, H. Y.; Qi, D. G.; Qi, S. Y.; Qian, F.; Sun, N. L.; Wang, H. Y.; Wang, N. F.; Yang, Y. M.; Zeng, H.; Zhang, F.; Zhang, F. R.; Zhang, L.; Bohorquez, R.; Rosas, J. F.; Saent, L.; Vacca, M.; Velasco, V. M.; Belohlavek, J.; Cernohous, M.; Choura, M.; Dedek, V.; Filipensky, B.; Hemzsky, L.; Karel, I.; Kopeckova, I.; Kovarova, K.; Labrova, R.; Madr, T.; Poklopova, Z.; Rucka, D.; Simon, J.; Skalicka, H.; Smidova, M.; Spinar, J.; Dodt, K. K.; Egstrup, K.; Friberg, J.; Haar, D.; Husted, S.; Jensen, G. V.; Joensen, A. M.; Klarlund, K. K.; Lind Rasmussen, S.; Melchior, T. M.; Olsen, M. E.; Poulsen, M. K.; Ralfkiaer, N.; Rasmussen, L. H.; Skagen, K.; Airaksinen, K. E.; Huikuri, H. V.; Hussi, E. J.; Kettunen, P.; Mänttäri, M.; Melin, J. H.; Mikkelsson, J.; Peuhkurinen, K.; Virtanen, V. K.; Ylitalo, A.; Agraou, B.; Boucher, L.; Bouvier, J. M.; Boye, A.; Boye, B.; Decoulx, E. M.; Defaye, P.; Delay, M.; Desrues, H.; Gacem, K.; Igigabel, P.; Jacon, P.; Leparree, S.; Magnani, C.; Martelet, M.; Movallem, J.; Olive, T.; Poulard, J. E.; Tiam, B.; Appel, K. F.; Appel, S.; Bansemir, L.; Borggrefe, M.; Brachmann, J.; Bulut-Streich, N.; Busch, K.; Dempfle, C. E. H.; Desaga, M.; Desaga, V.; Dormann, A.; Fechner, I.; Genth-Zotz, S.; Haberbosch, W. G.; Harenberg, J.; Haverkamp, W. L.; Henzgen, R.; Heuer, H.; Horacek, T.; Huttner, H. B.; Janssens, U.; Jantke, H. J.; Klauss, V.; Koudonas, D.; Kreuzer, J.; Kuckuck, H.; Maselli, A.; Müegge, A.; Munzel, T. F.; Nitsche, K.; Nledegjen, A.; Parwani, A.; Pluemer-Schmidt, M.; Pollock, B. W.; Salbach, B. I.; Salbach, P. B.; Schaufele, T.; Schoels, W.; Schwab, S.; Siegmund, U.; Veltkamp, R.; Von Hodenberg, E.; Weber, R.; Zechmeister, M.; Anastasopoulous, A. A.; Foulidis, V. O.; Kaldara, E.; Karamitsos, K.; Karantzis, J.; Kirpizidis, H.; Kokkinakis, C.; Krommydas, A.; Lappas, C.; Lappas, G. I.; Manolis, A.; Manolis, A. S.; Orfanidis, Z.; Papamichalis, M.; Peltekis, L.; Savvas, S.; Skoumpourdis, E. A.; Stakos, D. A.; Styliadis, I.; Triposkiadis, F.; Tsounis, D.; Tziakas, D. N.; Zafiridis, T.; Zarifis, J. H.; Chan, G. C. P.; Chan, W. K.; Chan, W. S.; Lau, C. L.; Tse, H. F.; Tsui, P. T.; Yu, C. M.; Yue, C. S.; Fugedi, K.; Garai, B.; Jánosi, A.; Kadar, A.; Karpati, P.; Keltai, K.; Kosa, I.; Kovacs, I.; Laszlo, Z.; Mezei, L.; Rapi, J.; Regos, L. I.; Szakal, I.; Szigyarto, I.; Toth, K.; Zsa'ry, A.; Agarwal, D. K.; Aggarwal, R. K.; Arulvenkatesh, R.; Bharani, A.; Bhuvaneswaran, J. S.; Byrapaneni, R. B.; Chandwani, P.; Chopra, S.; Desai, N.; Deshpande, V.; Golla, N. P.; Gupta, J. B.; Haridas, K. K.; Hiremath, J.; Jain, A. S.; Jain, M.; Jhala, D. A.; Joseph, J.; Kaila, M.; Kannaiyan, A.; Kumar, S.; Kuruvila, P.; Mahorkar, V. K.; Metha, A.; Naik, A. M.; Narayanan, S.; Panwar, R. B.; Reddy, C.; Sawhney, J. P. S.; Shah, S. M.; Sharma, S.; Shetty, G. S.; Sinha, N.; Sontakke, N. N.; Srinivas, A.; Trivedi, M. R.; Vadagenalli, P. S.; Vijayakumar, M.; Ben-Aharon, Y.; Benhorin, J.; Bogomolny, N.; Botwin-Shimko, S.; Bova, I.; Brenner, B.; Burstein, M.; Butnaru, A.; Caspi, A.; Danenberg, H. D.; Dayan, M.; Eldar, M.; Elian, D.; Elias, M.; Elis, A.; Esanu, G.; Genin, I.; Goldstein, L. H.; Grossman, E.; Hamoud, S.; Hayek, T.; Ilani, N.; Ilia, R.; Klainman, E. I.; Leibowitz, A.; Leibowitz, D.; Levin, I.; Lishner, M.; Lotan, C.; Mahagney, A.; Marmor, A.; Motro, M.; Peres, D.; Plaev, T.; Reisen, L. H.; Rogowski, O.; Schwammenthal, E.; Schwammenthal, Y.; Shechter, M.; Shochat, M.; Shotan, A.; Strasberg, B.; Sucher, E.; Telman, G.; Turgeman, Y.; Tzoran, I.; Weiss, A. T.; Weitsman, T.; Weller, B.; Wexler, D. H.; Wolff, R.; Yarnitsky, D.; Zeltser, D.; Argiolas, G.; Arteni, F.; Barbiero, M.; Bazzucco, R.; Bernardi, D.; Bianconi, L.; Bicego, D.; Brandini, R.; Bresciani, B.; Busoni, F.; Carbonieri, E.; Carini, M.; Catalano, A.; Cavallini, C.; D'Angelo, G.; de Caterina, R.; Di Niro, M.; Filigheddu, F.; Fraticelli, A.; Marconi, R.; Mennuni, M.; Moretti, L.; Mos, L.; Pancaldi, L. G.; Pirelli, S.; Renda, G.; Santini, M.; Tavarozzi, I.; Terrosu, P.; Uneddu, F.; Viccione, M.; Zanini, R.; Zingarini, G.; Aoyagi, T.; Eguma, H.; Fujii, K.; Fukuchi, M.; Fukunami, M.; Furukawa, Y.; Furuya, J.; Haneda, K.; Hara, S.; Hiroe, M.; Iesaka, Y.; Iijima, T.; Ishibashi, Y.; Iwade, K.; Kajiya, T.; Kakinoki, S.; Kamakura, S.; Katayama, Y.; Kihara, Y.; Kimura, K.; Kobayashi, S.; Kono, K.; Koretsune, Y.; Marui, N.; Matsuyama, T.; Meno, H.; Miyamoto, N.; Morikawa, S.; Myojin, K.; Nakamura, T.; Nishi, Y.; Ogawa, T.; Onaka, H.; Sakakibara, T.; Sakurai, S.; Sasaki, Y.; Sato, H.; Sugii, M.; Sumii, K.; Suzuki, S.; Takagi, M.; Takenaka, T.; Takeuchi, K.; Tanaka, S.; Tanouchi, J.; Ueda, K.; Ueyama, Y.; Ujihira, T.; Usui, M.; Yagi, M.; Yamada, T.; Yamamoto, H.; Yokochi, M.; Zen, E.; Abd Ghaphar, A. K.; Ang, C. K.; Chee, K. H.; Fong, A. F. Y.; Ismail, O.; Jeyaindran, S.; Kaur, S.; Lee, T. C.; Sandhu, R. S.; Shah, R. P.; Suganthi, S.; Zainal Abidin, S.; Alvarado-Ruiz, R.; Carrillo, J.; Delgado, E.; Fernandez Bonetti, P. A.; Leiva, J. L.; Meaney, A.; Olvera, R.; Peralta-Heredia, R.; Rodriguez, I.; Ruiz Rabasa, C. M.; Solache, G.; Villeda Espinosa, E.; Ahmed, S.; Badings, E.; Bartels, G. L.; Beganovic, M.; Bruning, T. A.; Ciampricotti, R.; Cozijnsen, L.; Crijns, H. J.; Daniels, M. C. G.; de Waard, D. E. P.; den Hartog, F. R.; Dirkali, A.; Groenemeijer, B. E.; Heesen, W. F.; Heijmeriks, J. A.; Hoogslag, P. A.; Huizenga, A.; Idzerda, H. H.; Kragten, J. A.; Krasznai, K.; Lenderink, T.; Liem, A. H.; Linssen, G. C.; Lok, D. J.; Meeder, J. G.; Michels, H. R.; Plomp, J.; Pos, L.; Posma, J. L.; Postema, P. G.; Salomonsz, R.; Stoel, I.; Tans, J. G.; Thijssen, H. J.; Timmermans, A. J. M.; Tteleman, R. G.; van Bergen, P. F. M. M.; van de Klippe, H. A.; van der Zwaan, C.; van Eck, J. W. M.; van Es, A. J. J.; van Gelder, I. C.; van Kempen, L. H.; van Kesteren, H. A.; van Rossum, P.; Veldmeyer, S.; Wilde, A. A. M.; Arnesen, H.; Atar, D.; Breder, O.; Istad, H.; Radunovic, Z.; Rykke, D. E.; Sirnes, P. A.; Tveit, A.; Ulimoen, S. R.; Cabrera, W.; Duenas, R.; Heredia, J. M.; Horna, M. E.; Hurtado, Y.; Salazar, P. M.; Abola, M. T. B.; Anonuevo, J. C.; Arellano, R. S.; Dioquino, C.; Morales, D. D.; Reyes, E. B.; Rogelio, G. G.; Roxas, A. A.; Sulit, D. J. V.; Bacior, B.; Dulak, E.; Gniot, J.; Goncikowski, J.; Grodecki, J.; Kalarus, Z. F.; Kawecka-Jaszcz, K.; Miekus, P.; Monies, F.; Piepiorka, M.; Pilichowska, E.; Plizio, E.; Rekosz, J.; Rybicka-Musialik, A.; Streb, W. A.; Styczkiewicz, M.; Szpajer, M.; Trusz-Gluza, M.; Wasilewska-Piepiorka, A.; Adragao, P.; Branco, V.; Canhão, P.; Cunha, L.; Falcão, F.; Lopes, G.; Machado, C.; Martinez-Marcos, J.; Monteiro, P. F.; Parreira, L.; Pinto, A. N.; Providencia, L. A.; Salgado, A. V.; Santos, J. F.; Timoteo, A. T.; Capalneanu, R.; Cinteza, M. A.; Margulesai, A. D.; Turdeanu, D. S.; Vintila, V. D.; Baranov, V. L.; Berngardt, E. R.; Dzhordzhikiya, T. R.; Gordeev, I. G.; Grigoryev, Y. V.; Isaeva, M. U.; Ivleva, A. Y.; Kokorin, V. A.; Komarov, A. L.; Maximenko, O. K.; Maykov, E. B.; Novikova, N.; Novikova, T. N.; Panchenko, E. P.; Poltavskaya, M. G.; Popova, Y. N.; Pronina, S. A.; Revishvili, A. Sh; Shlyakhto, E. V.; Shustov, S. B.; Sidorenko, B. A.; Sinopalnikov, A. I.; Sulimov, V.; Syrkin, A. L.; Titkov, A. Y.; Titkov, Y. S.; Zateyshchikov, D. A.; Zavaritskaya, O. P.; Chia, P. L.; Foo, D.; Sim, K. L.; Bugan, V.; Buganova, I.; Dúbrava, J.; Kaliska, G.; Masarovicova, M.; Mikes, P.; Mikes, Z.; Murin, J.; Pella, D.; Rybar, R.; Sedlák, J.; Skamla, M.; Spurný, P.; Strbova, J.; Uhliar, R.; Disler, L. J.; Engelbrecht, J. M.; Jankelow, D.; King, J.; Klug, E. Q.; Munnick, M.; Okreglicki, A. M.; Routier, R. J.; Snyders, F. A.; Theron, H. D.; Wittmer, H.; Cha, T. J.; Cho, J. G.; Choi, I. S.; Choi, J. I.; Choi, K. J.; Han, K. R.; Heo, J. H.; Jang, S. W.; Kang, T. S.; Kim, H. S.; Kim, K. S.; Kim, S. J.; Kim, S. S.; Kim, Y. H.; Kim, Y. N.; Lee, M. H.; Lee, M. Y.; Nam, G. B.; Oh, D. J.; Park, H. W.; Park, J. S.; Rho, T. H.; Shin, D. G.; Shin, E. K.; Alonso, J. J.; Cano, L.; Castellano, N. P.; Criado-Millan, A. J.; Curcio, A.; Egea, P.; Escudier, J. M.; Grande, A.; Grande, J. M.; Gusi-Tragant, G.; Lozano, I. F.; Martin, A. M.; Martinez-Rubio, A.; Mont, L.; Perez-Villacastin, J.; Sosa, L.; Ali, M.; Andersson, T.; Bandh, S.; Blomstrom Lundqvist, C. M.; Cherfan, P.; Fengsrud, E.; Fluur, C.; Herlitz, J.; Hijazi, Z.; Hoglund, N.; Hojeberg, B.; Jabro, J.; Juhlin, T.; Kjellman, B.; Lonnberg, I.; Maru, F.; Morlid, L.; Nilsson, O. R.; Ronn, F.; Rosenqvist, M.; Walfridsson, H.; Engelter, S. T.; Gallino, A.; Lyrer, P. A.; Moccetti, T.; Petrova, I.; Chang, Y. J.; Chen, C. H.; Chen, M. Y. C.; Cheng, J. J.; Chiang, T. R.; Chung, W. T.; Hsia, C. H.; Hsu, C. Y.; Hu, H. H.; Jeng, J. S.; Lai, W. T.; Lien, L. M.; Lin, K. H.; Liu, C. H.; Lo, H. S.; Peng, G. S.; Po, H. L.; Ryu, S. J.; Tsai, C. D.; Tsai, L. M.; Tseng, C. D.; Wang, J. H.; Wang, S. F.; Yang, S. P.; Kiatchoosakun, S.; Krittayaphong, R.; Kuanprasert, S.; Ngarmukos, T.; Simtharakaew, T.; Sukanandachai, B.; Sukonthasam, A.; Suwanagool, A.; Tatsanavivat, P.; Atmaca, Y.; Baris, N.; Boyaci, B.; Demir, M.; Guneri, S.; Usal, A.; Yalcin, R.; Amosova, K. M.; Beregova, O. P.; Besaga, Y. E. M.; Ikorkin, M. R.; Karapetyan, K.; Karpenko, O. I.; Kononenko, L.; Kuryata, O.; Martynova, L.; Motylevska, T.; Okhryamkina, O.; Pavlyk, S. S.; Perepelytsya, M. V.; Rudenko, L. V.; Skarzhevsky, O. A.; Tkachenko, L. A.; Tseluyko, V.; Usan, N.; Voronkov, L. G.; Yshchenko, K. V.; Zharinov, O. J.; Bryson, V. G.; Butler, R.; Cargill, R. I.; Chahal, N. S.; Cleland, J. G.; Cohen, A. T.; Cruddas, E. M.; Davey, P.; Davies, J.; Ford, S. L.; Griffith, K.; Haynes, R.; Hill, S.; Javed, M.; Kadr, H. H.; Lip, G. H.; Machin, J.; McEneaney, D. J.; McInnes, G. T.; McNeill, A. J.; Moriarty, A. J.; Muir, S.; O'Callaghan, J.; Purvis, J. A.; Pye, M.; Senior, R.; Sutton, D. A.; Thomas, S. H. L.; Wilkinson, P. R.; Wilmott, R.; Wrigley, M. J.; Abadier, R.; Abbud, Z. A.; Adams, K. V.; Adler, S. W.; Agarwal, S.; Ahmed, A. M.; Ahmed, I. S.; Aiuto, M. A.; Albrittun, T. D.; Aliyar, P.; Allan, J. J.; Allen, D. P.; Allen, S. L.; Altschuller, A.; Amin, M.; Anand, I. S.; Antolick, A. B.; Arora, R.; Arouni, A. J.; Arslanian, C. L.; Asinger, R. W.; Aycock, G. R.; Bariciano, R. J.; Baron, S. B.; Barr, M. A.; Bartkowiak, A. J.; Baruch, L.; Basignani, C.; Bass, M. L.; Bean, B.; Bedwell, N. W.; Belber, A. D.; Belew, K.; Bell, Y. C.; Bellinger, R. L.; Bennett, W. T.; Bensimhon, D. R.; Benton, R.; Benton, R. E.; Ben-Yehuda, O.; Bertolet, B. D.; Betkowski, A. S.; Bilazarian, S. D.; Bissette, J. K.; Bobade, M. B.; Bolster, D. E.; Bomba, J.; Book, D. M.; Boscia, J. A.; Bouchard, A.; Bowman, L. M.; Bradley, A. J.; Brandt, H. D.; Bricker, C. R.; Brobyn, T. L.; Brock, R. I.; Broderick, T. M.; Broedlin, K.; Brown, A. M.; Browne, K. F.; Burke, S. W.; Burton, M. E.; Buser, G. A.; Capasso, M. K.; Caplan, W. E.; Cappelli, J.; Cardona, C.; Cardona, F.; Carlson, T.; Carr, K. W.; Casey, T.; Cashion, W. R.; Cass, D. T.; Chandrashekar, Y. S.; Changlani, M.; Chapla, P. G.; Chappell, J. H.; Chen, C.; Chen, Y.; Cho, N. R.; Cieszkowski, J. H.; Clark, D. M.; Clayton, R.; Clogston, C. W.; Cockrell, D. J.; Cohen, A. I.; Cohen, T. J.; Cole, J. F.; Conway, G.; Cook, V. R.; Cornish, A. L.; Cossu, S. F.; Costello, D. L.; Courtade, D. J.; Covelli, H. C.; Crenshaw, B. S.; Crews, L. A.; Crossley, G. H.; Culp, S. C.; Curtis, B. M.; Darrow, K.; de Raad, R. E.; DeGregorio, M.; DelNegro, A. A.; Denny, D. M.; Desai, V. S.; Deumite, N. J.; Dewey, L.; Dharawat, R. N.; Dobbs, B.; Donahue, S. M.; Downey, B.; Downing, J.; Drehobl, M. A.; Drewes, W. A.; Drucker, M. N.; Duff, R.; Duggal, M.; Dunlap, S. H.; Dunning, D. W.; DuThinh, V.; Dykstra, G. T.; East, C.; Eblaghie, M. C.; Edelstein, J.; Edmiston, W. A.; Eisen, H. J.; Eisenberg, S. J.; Ellis, J. R.; Ellison, H. S.; Ellsworth, S.; Elshahawy, M.; Emlein, G.; Entcheva, M.; Essandoh, L. K.; Estrada, A. Q.; Ewing, B.; Faillace, R. T.; Fanelli, A.; Farrell, P. W.; Farris, S. W.; Fattal, P. G.; Feigenblum, D. Y.; Feldman, G. J.; Fialkow, J. A.; Fiddler, K. M.; Fields, R. H.; Finkel, M. S.; Finn, C.; Fischell, T. A.; Fishbach, M.; Fishbein, G. J.; Fisher, M. M.; Fleischhauer, F. J.; Folk, T. G.; Folkerth, S. D.; Fortman, R. R.; Frais, M. A.; Friedman, D. C.; Fuchs, G.; Fuller, F.; Garibian, G.; Gee, F. H.; Gelernt, M. D.; Genovely, H. C.; Gerber, J. R.; Germano, J. J.; Giardina, J. J.; Gilbert, J. M.; Gillespie, E. L.; Gilman, E. M.; Gitler, B.; Givens, D. H.; Glover, R.; Gogia, H. S.; Gohn, D. C.; Goldberg, R. K.; Goldberger, J. J.; Goldscher, D. A.; Goldstein, M.; Goraya, T.; Gordon, D. F.; Gottlieb, D.; Grafner, H. L.; Graham, M.; Graves, M. W.; Graziano, M.; Greco, S. N.; Greenberg, M. L.; Greenspon, A. J.; Greer, G. S.; Griffin, D. D.; Grogan, E. W.; Groo, V. L.; Guarnieri, T.; Gupta, A.; Gupta, J.; Hack, T. C.; Hall, B.; Hallak, O.; Halpern, S. W.; Hamburg, C.; Hamroff, G. S.; Han, J.; Handel, F.; Hankins, S. R.; Hanovich, G. D.; Hanrahan, J. A.; Haque, I. U.; Hargrove, J. L.; Harnick, P. E.; Harris, J. L.; Hartley, P. A.; Haskel, E. J.; Hatch, D.; Haught, W. H.; Hearne, S.; Hearne, S. E.; Hemphill, J. A.; Henderson, D. A.; Henes, C. H.; Hengerer-Yates, T.; Hermany, P. R.; Herzog, W. R.; Hickey, K.; Hilton, T. C.; Hockstad, E. S.; Hodnett, P.; Hoffmeister, R.; Holland, J.; Hollenweger, L.; Honan, M. B.; Hoopes, D. A.; Hordes, A. R.; Hotchkiss, D. A.; Howard, M. A.; Howard, V. N.; Hulyalkar, A. R.; Hurst, P.; Hutchison, L. C.; Ingram, J.; Isakov, T.; Ison, R. K.; Israel, C. N.; Jackson, B. K.; Jackson, K. N.; Jacobson, A. K.; Jain, S.; Jarmukli, N. F.; Joffe, I.; Johnson, L. E.; Johnson, S. A.; Johnson, S. L.; Jones, A. A.; Joyce, D. B.; Judson, P. L.; Juk, S. S.; Kaatz, S.; Kaddaha, R. M.; Kaplan, K. J.; Karunaratne, H. B.; Kennett, J. D.; Kenton, D. M.; Kettunen, J. A.; Khan, M. A.; Khant, R. N.; Kirkwood, M. D.; Knight, B. P.; Knight, P. O.; Knutson, T. J.; Kobayashi, J. F.; Kogan, A.; Kogan, A. D.; Koren, M. J.; Kosinski, E. J.; Kosolcharoen, P.; Kostis, J. B.; Kramer, J. H.; Kramer, S. D.; Kron, J.; Kuchenrither, C. R.; Kulback, S. J.; Kumar, A.; Kushner, D.; Kutscher, A.; Lai, C. K.; Lam, J. B.; Landau, C.; Landzberg, J. S.; Lang, D. T.; Lang, J. M.; Lanzarotti, C. J.; Lascewski, D. L.; Lau, T. K.; Lee, J. K.; Lee, S.; Leimbach, W. N.; LePine, A. M.; Lesser, M. F.; Leuchak, S. H.; Levy, R. M.; Lewis, W. R.; Lincoln, T. L.; Lingerfelt, W. M.; Liston, M.; Liu, Z. G.; Lloret, R. L.; Lohrbauer, L.; Longoria, D. C.; Lott, B. M.; Louder, D. R.; Loukinen, K. L.; Lovell, J.; Lue, S.; Mackall, J. A.; Maletz, L.; Marlow, L.; Martin, R. C.; Matsumura, M.; McCartney, M. J.; McDuffie, D.; McGough, M. F.; McGrew, F. A.; McGuinn, Wm P.; McMillen, M. D.; McNeff, J.; McPherson, C. A.; Meengs, M. E.; Meengs, W. L.; Meholick, A. W.; Meisner, J. S.; Melucci, M. B.; Mercando, A.; Merlino, J. D.; Meymandi, S. K.; Miele, M. B.; Miller, R. H.; Miller, S. H.; Minor, S. T.; Mitchell, M. R.; Modi, M.; Mody, F. V.; Moeller, C. L.; Moloney, J. F.; Moran, J. E.; Morcos, N. C.; Morgan, A.; Mukherjee, S. K.; Mullinax, K.; Murphy, A. L.; Mustin, A. J.; Myers, G. I.; Naccarelli, G. V.; Nadar, V. K.; Nallasivan, M.; Navas, J. P.; Niazi, I. K.; Nsah, E. N.; Nunamaker, J. L.; Ochalek, T. B.; O'dea, D. J.; Ogilvie, P. D.; Olliff, B.; Omalley, A. K.; O'Neill, P. G.; Onufer, J. R.; Orchard, R. C.; Orihuela, L. A.; Ortiz, E. C.; O'Sullivan, M. T.; Padanilam, B. J.; Pandey, P.; Patel, D. V.; Patel, R. J.; Patel, V. B.; Patlola, R. R.; Pennock, G. D.; Perlman, R.; Peters, P. H.; Petrillo, A. V.; Pezzella, S.; Phillips, D.; Pierre-Louis, J. R.; Pilcher, G.; Pillai, C.; Pollock, S. G.; Pond, M. S.; Porterfield, J. K.; Presant, L.; Pressler, J.; Pribble, A. H.; Promisloff, S. D.; Pudi, K. K.; Putnam, D. L.; Quartner, J.; Quinn, J. C.; Quinnell, C. M.; Raad, G. L.; Rasmussen, L. A.; Ray, C.; Reiffel, J. A.; Reynertson, S.; Richardson, J. W.; Riley, C. P.; Rippy, J. S.; Rittelmeyer, J. T.; Roberts, D. M.; Robertson, R.; Robinson, V. J. B.; Rocco, T. A.; Rosenbaum, D.; Roth, E. M.; Rottman, J. N.; Rough, R. R.; Rubenstein, J. J.; Sakkal, A. M.; Saleem, T.; Salerno, D. M.; Samendinger, M. L.; Sandeno, S.; Santilli, T. M.; Santucci, P.; Sattar, P.; Saxman, K. A.; Schaefer, S.; Schmidt, J.; Schneider, R. M.; Schocken, D. D.; Schrader, M. K.; Schramm, B. A.; Schultz, R. W.; Schussheim, A. E.; Schwarz, E. F.; Seamon, M. C.; Sestero, J. D.; Shah, M. P.; Shah, R.; Shalaby, A.; Shanes, J. G.; Sheftel, G. L.; Sheikh, K. H.; Shein, A. B.; Shemonsky, N. K.; Shepler, A.; Sheridan, E.; Shipwash, T. M.; Shopnick, R. I.; Short, W. G.; Shoukfeh, M. F.; Sibia, R. S.; Siler, T. M.; Silva, J. A.; Simons, G. R.; Simpson, A. G.; Simpson, H. R.; Simpson, V. J.; Singh, B. N.; Singh, N.; Singh, V. N.; Sitz, C. J.; Skatrud, L.; Sklar, J.; Slotwiner, D. J.; Smith, P. F.; Smith, P. N.; Smith, R. H.; Smith, J. E.; Sodowick, B. C.; Solomon, A. J.; Soltero, E. A.; Sonel, A. F.; Sperling, R.; Spiller, C.; Spink, B. Z.; Sprinkle, L. W.; Spyropoulos, A. C.; Stamos, T. D.; Steljes, A. D.; Stillabower, M. E.; Stover, T.; Strain, J. E.; Strickland, T. L.; Suresh, D. P.; Takata, T. S.; Taylor, J. S.; Taylor, M.; Teague, S. M.; Teixeia, J. M.; Telfer, E. A.; Terry, P. S.; Terry, R. W.; Thai, H. M.; Thalin, M.; Thomas, V. N.; Thompson, C. A.; Thompson, M. A.; Thornton, J. W.; Tidman, R. E.; Toler, B. S.; Traina, M. I.; Trippi, J. A.; Ujiiye, D. L.; Usedom, J. E.; van de Graaff, E.; van de Wall, L. R.; Vaughn, J. W.; Ver Steeg, D.; Vicari, R. M.; Vijay, N.; Vitale, C. B.; Vlastaris, A. G.; Voda, J.; Vora, K. N.; Voyles, W. F.; Vranian, R. B.; Vrooman, P. S.; Waack, P.; Waldo, A. L.; Walker, J. L.; Wallace, M. A.; Walsh, E. A.; Walsh, R. L.; Walton, A.; Washam, M.; Wehner, P. S.; Wei, J. Y.; Weiner, S.; Weiss, R. J.; Wells, D. M.; Wera-Archakul, W.; Wertheimer, J. H.; West, S. A.; Whitaker, J. H.; White, M. L.; White, R. H.; Whitehill, J. N.; Wiegman, P. J.; Wiesel, J.; Williams, J.; Williams, L. E.; Williams, M. L.; Williamson, V. K.; Wilson, V. E.; Wilson, W. W.; Woodfield, S. L.; Wulff, C. W.; Yates, S. W.; Yousuf, K. A.; Zakhary, B. G.; Zambrano, R.; Zimetbaum, P.; Zoble, R.; Zopo, A. R.; Zwerner, P. L.

2009-01-01

BACKGROUND: Warfarin reduces the risk of stroke in patients with atrial fibrillation but increases the risk of hemorrhage and is difficult to use. Dabigatran is a new oral direct thrombin inhibitor. METHODS: In this noninferiority trial, we randomly assigned 18,113 patients who had atrial

Percutaneous left atrial appendage closure for stroke prevention

DEFF Research Database (Denmark)

De Backer, Ole; Loupis, Anastasia M; Ihlemann, Nikolaj

2014-01-01

INTRODUCTION: In atrial fibrillation (AF) patients with an increased stroke risk, oral anticoagulation (OAC) is the standard treatment for stroke prevention. However, this therapy carries a high risk of major bleeding. Percutaneous closure of the left atrial appendage (LAA) is suggested as an alt...

Intracardiac impedance response during acute AF internal cardioversion using novel rectilinear and capacitor-discharge waveforms.

Science.gov (United States)

Rababah, A S; Walsh, S J; Manoharan, G; Walsh, P R; Escalona, O J

2016-07-01

Intracardiac impedance (ICI) is a major determinant of success during internal cardioversion of atrial fibrillation (AF). However, there have been few studies that have examined the dynamic behaviour of atrial impedance during internal cardioversion in relation to clinical outcome. In this study, voltage and current waveforms captured during internal cardioversion of acute AF in ovine models using novel radiofrequency (RF) generated low-tilt rectilinear and conventional capacitor-discharge based shock waveforms were retrospectively analysed using a digital signal processing algorithm to investigate the dynamic behaviour of atrial impedance during cardioversion. The algorithm was specifically designed to facilitate the simultaneous analysis of multiple impedance parameters, including: mean intracardiac impedance (Z M), intracardiac impedance variance (ICIV) and impedance amplitude spectrum area (IAMSA) for each cardioversion event. A significant reduction in ICI was observed when comparing two successive shocks of increasing energy where cardioversion outcome was successful. In addition, ICIV and IAMSA variables were found to inversely correlate to the magnitude of energy delivered; with a stronger correlation found to the former parameter. In conclusion, ICIV and IAMSA have been evidenced as two key dynamic intracardiac impedance variables that may prove useful in better understanding of the cardioversion process and that could potentially act as prognostic markers with respect to clinical outcome.

Correlation of right atrial appendage velocity with left atrial appendage velocity and brain natriuretic Peptide.

Science.gov (United States)

Kim, Bu-Kyung; Heo, Jung-Ho; Lee, Jae-Woo; Kim, Hyun-Soo; Choi, Byung-Joo; Cha, Tae-Joon

2012-03-01

Left atrial appendage (LAA) anatomy and function have been well characterized both in healthy and diseased people, whereas relatively little attention has been focused on the right atrial appendage (RAA). We sought to evaluate RAA flow velocity and to compare these parameters with LAA indices and with a study of biomarkers, such as brain natriuretic peptide, among patients with sinus rhythm (SR) and atrial fibrillation (AF). In a series of 79 consecutive patients referred for transesophageal echocardiography, 43 patients (23 with AF and 20 controls) were evaluated. AF was associated with a decrease in flow velocity for both LAA and RAA [LAA velocity-SR vs. AF: 61 ± 22 vs. 29 ± 18 m/sec (p vs. AF: 46 ± 20 vs. 19 ± 8 m/sec (p brain natriuretic peptide (BNP). AF was associated with decreased RAA and LAA flow velocities. RAA velocity was found to be positively correlated with LAA velocity and negatively correlated with BNP. The plasma BNP concentration may serve as a determinant of LAA and RAA functions.

Ebstein's anomaly as a cause of paroxysmal atrial fibrillation

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Damjanović Miodrag R.

2008-01-01

Full Text Available Background. Ebstein's anomaly is characterized by a displacement of the tricuspid valve toward apex, because of anomalous attachment of the tricuspid leaflets. There are type B of Wolff-Parkinson-White (WPW syndrome and paroxysmal arrhythmias in more than a half of all patients. Case report. We presented a female, 32-year old, with frequent paroxysms of atrial fibrillation. After conversion of rhythm an ECG showed WPW syndrome. Echocardiographic examination discovered normal size of the left cardiac chambers with paradoxical ventricular septal motion. The right ventricle was very small because of its atrialization. The origin of the tricuspid valve was 20 mm closer to apex of the right ventricle than the origin of the mitral valve. Electrophysiological examination showed a posterolateral right accesorial pathway. Atrial fibrillation was induced very easily in electrophysiological laboratory and a successful ablation of accessorial pathway was made. There were no WPW syndrome and paroxysms of atrial fibrillation after that. Conclusion. Ebstein's anomaly is one of the reasons of paroxysmal atrial fibrillation, especially in young persons with WPW syndrome.

Heart failure and atrial fibrillation: current concepts and controversies.

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Van den Berg, M. P.; Tuinenburg, A. E.; Crijns, H. J.; Van Gelder, I. C.; Gosselink, A. T.; Lie, K. I.

1997-01-01

Heart failure and atrial fibrillation are very common, particularly in the elderly. Owing to common risk factors both disorders are often present in the same patient. In addition, there is increasing evidence of a complex, reciprocal relation between heart failure and atrial fibrillation. Thus heart failure may cause atrial fibrillation, with electromechanical feedback and neurohumoral activation playing an important mediating role. In addition, atrial fibrillation may promote heart failure; in particular, when there is an uncontrolled ventricular rate, tachycardiomyopathy may develop and thereby heart failure. Eventually, a vicious circle between heart failure and atrial fibrillation may form, in which neurohumoral activation and subtle derangement of rate control are involved. Treatment should aim at unloading of the heart, adequate control of ventricular rate, and correction of neurohumoral activation. Angiotensin converting enzyme inhibitors may help to achieve these goals. Treatment should also include an attempt to restore sinus rhythm through electrical cardioversion, though appropriate timing of cardioversion is difficult. His bundle ablation may be used to achieve adequate rate control in drug refractory cases. PMID:9155607

LEFT ATRIAL APPENDAGE CLOSURE AS AN ALTERNATIVE TO WARFARIN FOR STROKE PREVENTION IN ATRIAL FIBRILLATION: A PATIENT¬LEVEL META¬ANALYSIS

Directory of Open Access Journals (Sweden)

2015-01-01

Full Text Available Holmes D.R. Jr, Doshi S.K., Kar S., et al. Left Atrial Appendage Closure as an Alternative to Warfarin for Stroke Prevention in Atrial Fibrillation: A Patient­Level Meta­Analysis // J. Am. Coll. Cardiol. – 2015. – Vol. 65. – P. 2614–2623.

The atrial fibrillation ablation pilot study

DEFF Research Database (Denmark)

Arbelo, Elena; Brugada, Josep; Hindricks, Gerhard

2014-01-01

AIMS: The Atrial Fibrillation Ablation Pilot Study is a prospective registry designed to describe the clinical epidemiology of patients undergoing an atrial fibrillation (AFib) ablation, and the diagnostic/therapeutic processes applied across Europe. The aims of the 1-year follow-up were to analyse...... was achieved in 40.7% of patients (43.7% in paroxysmal AF; 30.2% in persistent AF; 36.7% in long-lasting persistent AF). A second ablation was required in 18% of the cases and 43.4% were under antiarrhythmic treatment. Thirty-three patients (2.5%) suffered an adverse event, 272 (21%) experienced a left atrial...... tachycardia, and 4 patients died (1 haemorrhagic stroke, 1 ventricular fibrillation in a patient with ischaemic heart disease, 1 cancer, and 1 of unknown cause). CONCLUSION: The AFib Ablation Pilot Study provided crucial information on the epidemiology, management, and outcomes of catheter ablation of AFib...

Retroperitoneal unicentric Castleman's disease (giant lymph node hyperplasia: case report

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Jaques Waisberg

Full Text Available CONTEXT AND OBJECTIVE: Castleman's disease, or giant lymph node hyperplasia, is a rare disorder of the lymphoid tissue that causes lymph node enlargement. It is considered benign in its localized form, but aggressive in the multicentric type. The definitive diagnosis is based on postoperative pathological findings. The aim here was to describe a case of retroperitoneal unicentric Castleman's disease in the retroperitoneum. CASE REPORT: A 61-year old white male with weight loss and listlessness presented with moderate arterial hypertension and leukopenia. Abdominal tomography revealed a 5 x 4 x 5 cm oval mass of low attenuation, with inner calcification and intense enhancement on intravenous contrast, located in the retroperitoneal region, between the left kidney and the aorta, at the renal hilus. Exploratory laparotomy revealed a non-pulsatile solid oval mass situated in the retroperitoneum, adjacent to the left renal hilus. The retroperitoneal lesion was removed in its entirety. Examination of frozen samples revealed benign lymph node tissue and histopathological examination of the surgical sample revealed hyaline-vascular giant lymph node hyperplasia (Castleman's disease. The patient was discharged on the 12th day without significant events. Two months after the operation, the patient was readmitted with severe cardiac insufficiency, acute renal failure and bronchopneumonia, which progressed to acute respiratory insufficiency, sepsis and death.

Node-pair reliability of network systems with small distances between adjacent nodes

International Nuclear Information System (INIS)

Malinowski, Jacek

2007-01-01

A new method for computing the node-pair reliability of network systems modeled by random graphs with nodes arranged in sequence is presented. It is based on a recursive algorithm using the 'sliding window' technique, the window being composed of several consecutive nodes. In a single step, the connectivity probabilities for all nodes included in the window are found. Subsequently, the window is moved one node forward. This process is repeated until, in the last step, the window reaches the terminal node. The connectivity probabilities found at that point are used to compute the node-pair reliability of the network system considered. The algorithm is designed especially for graphs with small distances between adjacent nodes, where the distance between two nodes is defined as the absolute value of the difference between the nodes' numbers. The maximal distance between any two adjacent nodes is denoted by Γ(G), where G symbolizes a random graph. If Γ(G)=2 then the method can be applied for directed as well as undirected graphs whose nodes and edges are subject to failure. This is important in view of the fact that many algorithms computing network reliability are designed for graphs with failure-prone edges and reliable nodes. If Γ(G)=3 then the method's applicability is limited to undirected graphs with reliable nodes. The main asset of the presented algorithms is their low numerical complexity-O(n), where n denotes the number of nodes

The rise of China and the time of Africa: Gauging Afro-Sino relations ...

African Journals Online (AJOL)

The article focuses on Sino-African relations, with specific reference to South Africa. An outline is provided of recent developments as a roadmap for the unfolding of this relationship. The question of whether China's African interest can be seen as tacit colonisation is discussed. Even if these fears are allayed, the question ...

77 FR 11121 - Scientific Information Request on Treatment of Atrial Fibrillation

Science.gov (United States)

2012-02-24

... Information Request on Treatment of Atrial Fibrillation AGENCY: Agency for Healthcare Research and Quality... Review of the Treatment of Atrial Fibrillation, which is currently being conducted by the Evidence-based... the treatment of atrial fibrillation. The EHC Program is dedicated to identifying as many studies as...

PR Interval Associated Genes, Atrial Remodeling and Rhythm Outcome of Catheter Ablation of Atrial Fibrillation—A Gene-Based Analysis of GWAS Data

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Daniela Husser

2017-12-01

Full Text Available Background: PR interval prolongation has recently been shown to associate with advanced left atrial remodeling and atrial fibrillation (AF recurrence after catheter ablation. While different genome-wide association studies (GWAS have implicated 13 loci to associate with the PR interval as an AF endophenotype their subsequent associations with AF remodeling and response to catheter ablation are unknown. Here, we perform a gene-based analysis of GWAS data to test the hypothesis that PR interval candidate genes also associate with left atrial remodeling and arrhythmia recurrence following AF catheter ablation.Methods and Results: Samples from 660 patients with paroxysmal (n = 370 or persistent AF (n = 290 undergoing AF catheter ablation were genotyped for ~1,000,000 SNPs. Gene-based association was investigated using VEGAS (versatile gene-based association study. Among the 13 candidate genes, SLC8A1, MEIS1, ITGA9, SCN5A, and SOX5 associated with the PR interval. Of those, ITGA9 and SOX5 were significantly associated with left atrial low voltage areas and left atrial diameter and subsequently with AF recurrence after radiofrequency catheter ablation.Conclusion: This study suggests contributions of ITGA9 and SOX5 to AF remodeling expressed as PR interval prolongation, low voltage areas and left atrial dilatation and subsequently to response to catheter ablation. Future and larger studies are necessary to replicate and apply these findings with the aim of designing AF pathophysiology-based multi-locus risk scores.

Japanese Scholarship on the Sino-Japanese War, 2007–2012

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Duan Ruicong

2014-03-01

Full Text Available This article examines in detail the last five years of Japanese scholarship related to the Sino-Japanese War, highlighting its principle trends and achievements. Due to the broad range and large quantity of scholarship on the subject, Duan Ruicong focuses foremost on the 2007–2012 period, although by necessity this article also touches on pre-2007 scholarship. Additionally, this overview will primarily introduce Japanese-language, single-authored and co-authored books (monographs, collections of papers, and other single-issue publications; only when necessary will it refer to pertinent journal articles.

Hyperleptinemia Exacerbates High-Fat Diet-Mediated Atrial Fibrosis and Fibrillation.

Science.gov (United States)

Fukui, Akira; Ikebe-Ebata, Yuki; Kondo, Hidekazu; Saito, Shotaro; Aoki, Kohei; Fukunaga, Naoya; Shinohara, Tetsuji; Masaki, Takayuki; Teshima, Yasushi; Takahashi, Naohiko

2017-06-01

Obesity including metabolic syndrome is an independent risk factor of atrial fibrillation (AF). Although hyperleptinemia is usually a characteristic of obese subjects, the relationship with atrial fibrosis and AF is unknown. We tested the hypothesis that high-fat diet (HFD)-induced hyperleptinemia exacerbates atrial fibrosis and AF. Eight-week-old male C57BL/6 (WT) and leptin-deficient ob/ob (Ob) mice were treated with a normal-fat diet (NFD) or 60% HFD. After 8 weeks, transesophageal burst pacing and electrophysiological study using isolated perfused hearts were performed and left atrial (LA) tissues were collected for histological analysis, hydroxyproline assay, and reverse transcription-polymerase chain reaction. HFD treatment increased body weight in both WT and Ob mice compared with NFD (both P atrial fibrosis and AF. Inhibition of leptin signaling may become a novel therapeutic target to prevent obesity-related AF. © 2017 Wiley Periodicals, Inc.

Ventricular rhythm in atrial fibrillation under anaesthetic infusion with propofol

International Nuclear Information System (INIS)

Cervigón, R; Moreno, J; Pérez-Villacastín, J; Reilly, R B; Castells, F

2009-01-01

Changes in patients' autonomic tone and specific pharmacologic interventions may modify the ventricular response (actual heart rate) during atrial fibrillation (AF). Hypnotic agents such as propofol may modify autonomic balance as they promote a sedative state. It has been shown that propofol slightly slows atrial fibrillatory activity, but the net global effect on the ventricular response remains unknown. We aimed to evaluate in patients in AF the effect of a propofol bolus on the ventricular rate and regularity at ECG. We analysed the possible relation with local atrial fibrillatory activities, as ratios between atrial and ventricular rates (AVRs), analysing atrial activity from intracardiac electrograms at the free wall of the right and left atria and at the interatrial septum. We compared data at the baseline and after complete hypnosis. Propofol was associated with a more homogeneous ventricular response and lower AVR values at the interatrial septum

Study on the Introduction of High-Quality Educational Resources for Sino-Foreign Cooperative Education

Science.gov (United States)

Jinhui, Lin

2016-01-01

In Sino-foreign cooperative education, high-quality introduced educational resources must benefit the growth and development of students, facilitate the school's capacity building and the improvement of overall educational standards, and promote national socioeconomic development. It is necessary to establish and perfect the various working…

Assessment of blood stasis in left-atrial appendage with electron-beam CT: filling delay in atrial fibrillation

International Nuclear Information System (INIS)

Nakanishi, Tadashi; Hamada, Seiki; Takamiya, Makoto; Kuribayashi, Sachio; Naito, Hiroaki

1994-01-01

The left-atrial appendage (LAA) is the most frequent site of thrombus formation. The most probable reason is its anatomical structure and blood stasis. We hypothesized that peak time delay should occur in the LAA with stagnant blood flow. We measured peak time delay in LAA against left atrium with the flow-mode study of electron-beam CT for 49 patients (including 23 patients with atrial fibrillation [AF]). Volume-mode scannings were also performed to detect intracardiac thrombi. Patients with atrial fibrillation showed a larger value than those with sinus rhythm. Some AF patients with no filling of contrast media into the LAA and/or thrombus showed a larger value than the others. The value obtained by the flow-mode study might have the potential by the flow-mode study might have the potential to assess blood stasis and to predict the jeopardized state in the LAA. (orig.)

Assessment of blood stasis in left-atrial appendage with electron-beam CT: filling delay in atrial fibrillation

Energy Technology Data Exchange (ETDEWEB)

Nakanishi, Tadashi [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Hamada, Seiki [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Takamiya, Makoto [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Kuribayashi, Sachio [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Naito, Hiroaki [Biomedical Research Center, Osaka Univ. School of Medicine, Suita (Japan)

1994-10-01

The left-atrial appendage (LAA) is the most frequent site of thrombus formation. The most probable reason is its anatomical structure and blood stasis. We hypothesized that peak time delay should occur in the LAA with stagnant blood flow. We measured peak time delay in LAA against left atrium with the flow-mode study of electron-beam CT for 49 patients (including 23 patients with atrial fibrillation [AF]). Volume-mode scannings were also performed to detect intracardiac thrombi. Patients with atrial fibrillation showed a larger value than those with sinus rhythm. Some AF patients with no filling of contrast media into the LAA and/or thrombus showed a larger value than the others. The value obtained by the flow-mode study might have the potential by the flow-mode study might have the potential to assess blood stasis and to predict the jeopardized state in the LAA. (orig.)

Noninvasive evaluation of reverse atrial remodeling after catheter ablation of atrial fibrillation by P wave dispersion.

Science.gov (United States)

Fujimoto, Yuhi; Yodogawa, Kenji; Takahashi, Kenta; Tsuboi, Ippei; Hayashi, Hiroshi; Uetake, Shunsuke; Iwasaki, Yu-Ki; Hayashi, Meiso; Miyauchi, Yasushi; Shimizu, Wataru

2017-11-01

Atrial fibrillation (AF) itself creates structural and electrophysiological changes such as atrial enlargement, shortening of refractory period and decrease in conduction velocity, called "atrial remodeling", promoting its persistence. Although the remodeling process is considered to be reversible, it has not been elucidated in detail. The aim of this study was to assess the feasibility of P wave dispersion in the assessment of reverse atrial remodeling following catheter ablation of AF. Consecutive 126 patients (88 males, age 63.0 ± 10.4 years) who underwent catheter ablation for paroxysmal AF were investigated. P wave dispersion was calculated from the 12 lead ECG before, 1 day, 1 month, 3 months and 6 months after the procedure. Left atrial diameter (LAD), left atrial volume index (LAVI), left ventricular ejection fraction (LVEF), transmitral flow velocity waveform (E/A), and tissue Doppler (E/e') on echocardiography, plasma B-type natriuretic peptide (BNP) concentrations, serum creatinine, and estimated glomerular filtration rate (eGFR) were also measured. Of all patients, 103 subjects remained free of AF for 1 year follow-up. In these patients, P wave dispersion was not changed 1 day and 1 month after the procedure. However, it was significantly decreased at 3 and 6 months (50.1 ± 14.8 to 45.4 ± 14.4 ms, p < 0.05, 45.2 ± 9.9 ms, p < 0.05, respectively). Plasma BNP concentrations, LAD and LAVI were decreased (81.1 ± 103.8 to 44.8 ± 38.3 pg/mL, p < 0.05, 38.2 ± 5.7 to 35.9 ± 5.6 mm, p < 0.05, 33.3 ± 14.2 to 29.3 ± 12.3 mL/m 2 , p < 0.05) at 6 months after the procedure. There were no significant changes in LVEF, E/A, E/e', serum creatinine, and eGFR during the follow up period. P wave dispersion was decreased at 3 and 6 months after catheter ablation in patients without recurrence of AF. P wave dispersion is useful for assessment of reverse remodeling after catheter ablation of AF.

Role of Echocardiography in the Management and Prognosis of Atrial Fibrillation

Science.gov (United States)

Silverman, David I; Ayirala, Srilatha R; Manning, Warren J

2012-01-01

Echocardiography plays a longstanding and vital role in the management of atrial fibrillation (AF). Advances in 2D imaging, Doppler echocardiography and strain imaging have all contributed to major progress in AF treatment. Echocardiographically measured left atrial (LA) volume is a powerful predictor of maintenance of sinus rhythm following cardioversion as well as risk of thrombus formation and thromboembolism. Doppler derived parameters of atrial mechanical function including atrial ejection force provide related prognostic information. Transesophageal echocardiocardiograpy (TEE) guided cardioversion of AF allows for rapid conversion to sinus rhythm without prolonged oral anticoagulation, and TEE serves as a useful tool during catheter ablation of AF and atrial flutter. Newer measures derived from speckle tracking offer great promise in further improving the care of patients with AF. PMID:28496715

Atrial natriuretic peptide and feeding activity patterns in rats

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Oliveira M.H.A.

1997-01-01

Full Text Available This review presents historical data about atrial natriuretic peptide (ANP from its discovery as an atrial natriuretic factor (ANF to its role as an atrial natriuretic hormone (ANH. As a hormone, ANP can interact with the hypothalamic-pituitary-adrenal axis (HPA-A and is related to feeding activity patterns in the rat. Food restriction proved to be an interesting model to investigate this relationship. The role of ANP must be understood within a context of peripheral and central interactions involving different peptides and pathways

Vernakalant hydrochloride for the rapid conversion of atrial fibrillation after cardiac surgery

DEFF Research Database (Denmark)

Kowey, Peter R; Dorian, Paul; Mitchell, L Brent

2009-01-01

Postoperative atrial arrhythmias are common and are associated with considerable morbidity. This study was designed to evaluate the efficacy and safety of vernakalant for the conversion of atrial fibrillation (AF) or atrial flutter (AFL) after cardiac surgery....

Genetics of Atrial Fibrillation and Possible Implications for Ischemic Stroke

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Robin Lemmens

2011-01-01

Full Text Available Atrial fibrillation is the most common cardiac arrhythmia mainly caused by valvular, ischemic, hypertensive, and myopathic heart disease. Atrial fibrillation can occur in families suggesting a genetic background especially in younger subjects. Additionally recent studies have identified common genetic variants to be associated with atrial fibrillation in the general population. This cardiac arrhythmia has important public health implications because of its main complications: congestive heart failure and ischemic stroke. Since atrial fibrillation can result in ischemic stroke, one might assume that genetic determinants of this cardiac arrhythmia are also implicated in cerebrovascular disease. Ischemic stroke is a multifactorial, complex disease where multiple environmental and genetic factors interact. Whether genetic variants associated with a risk factor for ischemic stroke also increase the risk of a particular vascular endpoint still needs to be confirmed in many cases. Here we review the current knowledge on the genetic background of atrial fibrillation and the consequences for cerebrovascular disease.

Cost of illness of atrial fibrillation: a nationwide study of societal impact.

Science.gov (United States)

Johnsen, Søren Paaske; Dalby, Lene Worsaae; Täckström, Tomas; Olsen, Jens; Fraschke, Anina

2017-11-10

The prevalence of atrial fibrillation is increasing rapidly; however, to date, population-based data are lacking on the attributable cost of illness of atrial fibrillation from a societal perspective, including both direct and indirect costs. The study was an incidence-based cost-of-illness study based on national registries covering the entire population of Denmark. We identified all patients with a first-time hospital diagnosis of atrial fibrillation between 2001 and 2012. For every atrial fibrillation patient, we identified three age- and sex-matched controls from the general population. Both the total and the attributable costs of atrial fibrillation were estimated based on individual level information on hospital care (in- and out-patient contacts), primary sector care, use of prescription drugs and productivity loss. Average 3-year societal costs per patient attributable to atrial fibrillation were estimated to be €20,403-26,544 during the study period. The costs were highest during the first year after diagnosis of atrial fibrillation. Admission costs constituted the largest cost component, whereas primary sector costs and medicine costs only constituted minor components. The attributable costs were more than two-fold higher among patients experiencing a stroke. The total 3-year cost attributable to atrial fibrillation in Denmark was estimated to be €219-295 million. The societal costs attributable to atrial fibrillation are significant. Reducing the need for hospitalizations, in particular from stroke, is a key factor in controlling the costs.

Antihypertensive treatment and risk of atrial fibrillation

DEFF Research Database (Denmark)

Marott, Sarah C W; Nielsen, Sune F; Benn, Marianne

2014-01-01

AIMS: To examine the associations between antihypertensive treatment with angiotensin-converting enzyme inhibitors (ACEis) or angiotensin receptor blockers (ARBs), β-blockers, diuretics, or calcium-antagonists, and risk of atrial fibrillation. We examined these associations using the entire Danish...... population from 1995 through 2010. METHODS AND RESULTS: Excluding medication used in atrial fibrillation, we matched individuals on ACEi monotherapy 1:1 with individuals on β-blocker (n = 48 658), diuretic (n = 69 630), calcium-antagonist (n = 57 646), and ARB monotherapy (n = 20 158). Likewise, individuals...... on ARB monotherapy were matched 1:1 with individuals on β-blocker (n = 20 566), diuretic (n = 20 832), calcium-antagonist (n = 20 232), and ACEi monotherapy (n = 20 158). All were free of atrial fibrillation and of predisposing diseases like heart failure, ischaemic heart disease, diabetes mellitus...

[The contribution of inflammatory process in pathogenesis and natural history of atrial fibrillation].

Science.gov (United States)

Zyśko, Dorota; Gajek, Jacek; Mazurek, Walentyna

2005-02-01

The inflammatory process plays important role in pathogenesis of some cardiovascular diseases. Atrial fibrillation is atrial arrhythmia with rapid, asynchronous activation of atrial myocytes. The inflammatory process can be responsible for atrial electrical and anatomical remodeling and therefore shifts towards arrhythmia persistence. The presence of systemic inflammation may be assessed by means of C-reactive protein (CRP) measurement. Maximal concentration of CRP coincidences with the peak of paroxysmal atrial fibrillation occurrence in patients after cardiac surgery. In patients with sinus rhythm the concentration of CRP is a risk factor for this arrhythmia in long-term follow-up. In patients with atrial fibrillation mean CRP concentration is 2-fold higher comparing to control group. CRP concentration is higher in patients with chronic than paroxysmal form of this arrhythmia. High CRP level predicts worse results of direct current cardioversion and more frequent paroxysms of atrial fibrillation during follow-up. Besides of, the patients with echocardiographic signs of thromboembolic risk have higher CRP levels than control subjects. There is no data about the influence of anti-inflammatory therapy on atrial fibrillation or its recurrences.

Atrial Fibrillation: When the heart is not in rhythm | NIH MedlinePlus the Magazine

Science.gov (United States)

... of this page please turn JavaScript on. Feature: Atrial Fibrillation Atrial Fibrillation: When the heart is not in rhythm Past ... show, Deal With It . Photo: TBS/Deal Understanding Atrial Fibrillation Atrial fibrillation (AFib) is the most common type ...

Atrial flutter: from ECG to electroanatomical 3D mapping

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Livio Dei Cas

2009-08-01

Full Text Available Atrial flutter is a common arrhythmia that may cause significant symptoms, including palpitations, dyspnea, chest pain and even syncope. Frequently it’s possible to diagnose atrial flutter with a 12-lead surface ECG, looking for distinctive waves in leads II, III, aVF, aVL, V1,V2. Puech and Waldo developed the first classification of atrial flutter in the 1970s. These authors divided the arrhythmia into type I and type II. Therefore, in 2001 the European Society of Cardiology and the North American Society of Pacing and Electrophysiology developed a new classification of atrial flutter, based not only on the ECG, but also on the electrophysiological mechanism. New developments in endocardial mapping, including the electroanatomical 3D mapping system, have greatly expanded our understanding of the mechanism of arrhythmias. More recently, Scheinman et al, provided an updated classification and nomenclature. The terms like common, uncommon, typical, reverse typical or atypical flutter are abandoned because they may generate confusion. The authors worked out a new terminology, which differentiates atrial flutter only on the basis of electrophysiological mechanism. (Heart International 2006; 3-4: 161-70

Paroxysmal atrial fibrillation occurs often in cryptogenic ischaemic stroke

DEFF Research Database (Denmark)

Christensen, L M; Krieger, D W; Højberg, S

2014-01-01

BACKGROUND AND PURPOSE: Atrial fibrillation (AF) increases the risk of stroke fourfold and is associated with a poor clinical outcome. Despite work-up in compliance with guidelines, up to one-third of patients have cryptogenic stroke (CS). The prevalence of asymptomatic paroxysmal atrial fibrilla......BACKGROUND AND PURPOSE: Atrial fibrillation (AF) increases the risk of stroke fourfold and is associated with a poor clinical outcome. Despite work-up in compliance with guidelines, up to one-third of patients have cryptogenic stroke (CS). The prevalence of asymptomatic paroxysmal atrial...... lasting predominantly between 1 and 4 h. Four recurrent strokes were observed, three in patients with PAF; all three patients were on oral anticoagulation (OAC). CONCLUSIONS: One in five patients with CS had PAF, which occurred at low burden and long after stroke. Future studies should determine the role...

Atrial angioleiomyoma with myopericytoma-like features: a case report.

Science.gov (United States)

Nassereddine, Hussein; Cazes, Aurélie; Verdonk, Constance; Assous, Benjamin; Dautry, Raphael; Nataf, Patrick; Wassef, Michel; Deschamps, Lydia

A 66-year-old female patient was referred to our hospital for resection of a right atrial mass. Four months earlier, she had suffered an acute cerebrovascular accident due to occlusion of the sylvian segment of the right middle cerebral artery from atheromatous tight stenosis in the right internal carotid artery. Later, investigations with transthoracic and transesophageal echocardiography revealed a 3.4-cm right atrial mass that was resected surgically. Microscopic evaluation revealed a well-circumscribed nodular tumor, located within the interatrial septum, and corresponding to an angioleiomyoma (ALM). This tumor differs histologically from atrial myxoma. ALM is a ubiquitous benign tumor but has never been reported to occur in the atrium. ALM can mimic cardiac myxoma and should be considered in the differential diagnosis of atrial tumors. Copyright © 2017 Elsevier Inc. All rights reserved.

Rapid slowing of the atrial fibrillatory rate after administration of AZD7009 predicts conversion of atrial fibrillation

DEFF Research Database (Denmark)

Aunes, Maria; Egstrup, Kenneth; Frison, Lars

2014-01-01

to sinus rhythm (SR) and were matched to 35 non-converters. The mean AFR before conversion was 231 fibrillations per minute (fpm), having decreased by 41%; in non-converters, it was 296 fpm at the end of infusion, having decreased by 26%. The rate of decrease was greater in converters at 5 min, -88 vs. -66......BACKGROUND: Effects on the atrial fibrillatory rate (AFR) were studied during infusion with the combined potassium and sodium channel blocker AZD7009. METHODS AND RESULTS: Patients with persistent atrial fibrillation (AF) were randomized to AZD7009 or placebo. Thirty-five patients converted...... fpm (p=0.02), and at 10 min, -133 vs. -111 fpm (p=0.048). The AFR-SD and the exponential decay decreased. A small left atrial area was the only baseline predictor of conversion to SR. CONCLUSIONS: AZD7009 produced a significantly more rapid decrease of the AFR in converters than in non...

Observation of the efficacy of radiofrequency catheter ablation on patients with different forms of atrial fibrillation.

Science.gov (United States)

Zhao, R-C; Han, W; Han, J; Yu, J; Guo, J; Fu, J-L; Li, Z; Zhao, R-Z

2016-10-01

To study the efficacy and safety of radiofrequency catheter ablation (RFCA) in patients with different forms of atrial fibrillation. By retrospective analysis, we summarize 720 cases, where patients diagnosed with atrial fibrillation in our hospital were treated with RFCA from February 2010 to October 2014. Among the cases, 425 were diagnosed with paroxysmal atrial fibrillation and 295 with non-paroxysmal atrial fibrillation (including persistent atrial fibrillation and permanent atrial fibrillation). All patients were followed up until June 2015 to compare and analyze the differences in operation success rates, complications and recurrence rates. 395 cases (92.9%) of paroxysmal atrial fibrillation and 253 cases (85.8%) with non-paroxysmal atrial fibrillation were subject to surgery and followed up. The age of onset, disease course, underlying diseases, left atrial diameter and combined anti-arrhythmics of patients with paroxysmal atrial fibrillation were lower than those of patients with non-paroxysmal atrial fibrillation, and the differences were statistically significant (p success rate of the first ablation was higher than that of non-paroxysmal atrial fibrillation. Procedure time, procedure method, complications and recurrence rate of patients with paroxysmal atrial fibrillation were lower than those of non-paroxysmal atrial fibrillation group, and the differences were statistically significant (p failure caused by atrial fibrillation in the two groups, the difference was not statistically significant (Apoplexy: p = 0.186; Heart failure: p = 0.170). The individual ablation success rate was higher for paroxysmal atrial fibrillation, and long-term follow-up showed that the occurrence of apoplexy and heart failure was not different from the non-paroxysmal atrial fibrillation group.

Left Atrial Appendage Closure in Atrial Fibrillation: A World without Anticoagulation?

Directory of Open Access Journals (Sweden)

Tahmeed Contractor

2011-01-01

Full Text Available Atrial Fibrillation (AF is a common arrhythmia with an incidence that is as high as 10% in the elderly population. Given the large proportion of strokes caused by AF as well as the associated morbidity and mortality, reducing stroke burden is the most important part of AF management. While warfarin significantly reduces the risk of AF-related stroke, perceived bleeding risks and compliance limit its widespread use in the high-risk AF population. The left atrial appendage is believed to be the “culprit” for thrombogenesis in nonvalvular AF and is a new therapeutic target for stroke prevention. The purpose of this review is to explore the evolving field of percutaneous LAA occlusion. After briefly highlighting the risk of stroke with AF, problems with warfarin, and the role of the LAA in clot formation, this article discusses the feasibility and efficacy of various devices which have been developed for percutaneous LAA occlusion.

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.

Rapid pacing results in changes in atrial but not in ventricular refractoriness

NARCIS (Netherlands)

Schoonderwoerd, BA; Van Gelder, IC; Tieleman, RG; Bel, KJ; Crijns, HJGM

It is well known that atrial tachycardia causes atrial electrical remodeling, characterized by shortening of atrial effective refractory periods (AERPs) and loss of physiological adaptation of AERP to rate. However, the nature and time course of changes in ventricular effective refractory periods

Detection of Rapid Atrial Arrhythmias in SQUID Magnetocardiography

Energy Technology Data Exchange (ETDEWEB)

Kim, Ki Woong; Kwon, Hyuk Chan; Kim, Ki Dam; Lee, Yong Ho; Kim, Jin Mok; Kim, In Seon; Lim, Hyun Kyoon; Park, Yong Ki [Biomagnetism Research, Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Kim, Doo Sang [Seoul Veterans Hospital, Seoul (Korea, Republic of); Lim, Seung Pyung [Chungnam National University Hospital, Daejeon (Korea, Republic of)

2005-10-15

We propose a method to measure atrial arrhythmias (AA) such as atrial fibrillation (Afb) and atrial flutter (Afl) with a SQUID magnetocardiograph (MCG) system. To detect AA is one of challenging topics in MCG. As the AA generally have irregular rhythm and atrio-ventricular conduction, the MCG signal cannot be improved by QRS averaging; therefore a SQUID MCG system having a high SNR is required to measure informative atrial excitation with a single scan. In the case of Afb, diminished f waves are much smaller than normal P waves because the sources are usually located on the posterior wall of the heart. In this study, we utilize an MCG system measuring tangential field components, which is known to be more sensitive to a deeper current source. The average noise spectral density of the whole system in a magnetic shielded room was 10 fT/Hz(a) 1 Hz and 5 fT/Hz(a) 100 Hz. We measured the MCG signals of patients with chronic Afb and Afl. Before the AA measurement, the comparison between the measurements in supine and prone positions for P waves has been conducted and the experiment gave a result that the supine position is more suitable to measure the atrial excitation. Therefore, the AA was measured in subject's supine position. Clinical potential of AA measurement in MCG is to find an aspect of a reentry circuit and to localize the abnormal stimulation noninvasively. To give useful information about the abnormal excitation, we have developed a method, separative synthetic aperture magnetometry (sSAM). The basic idea of sSAM is to visualize current source distribution corresponding to the atrial excitation, which are separated from the ventricular excitation and the Gaussian sensor noises. By using sSAM, we localized the source of an Afl successfully.

Evaluation of atrial electromechanical delay and diastolic functions in patients with hyperthyroidism.

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Sokmen, Abdullah; Acar, Gurkan; Sokmen, Gulizar; Akcay, Ahmet; Akkoyun, Murat; Koroglu, Sedat; Nacar, Alper Bugra; Ozkaya, Mesut

2013-11-01

Hyperthyroidism is a well-known cause of atrial fibrillation (AF) which is associated with increased morbidity and mortality. Atrial electromechanical delay (EMD) is a significant predictor of AF. The aim of this study was to assess the atrial EMD and diastolic functions in subclinical and overt hyperthyroidism by using tissue Doppler imaging (TDI). The study population consisted of 3 groups: group I (30 healthy subjects), group II (38 patients with subclinical hyperthyroidism), and group III (25 patients with overt hyperthyroidism). Atrial electromechanical coupling was measured with TDI. Standard echocardiographic measurements and parameters of diastolic function were obtained by conventional echocardiography and TDI. Intra- and inter-atrial EMD were significantly prolonged in subclinical and overt hyperthyroidism compared with control group (P = 0.03 and P hyperthyroidism. TSH level and mitral Em /Am ratio were found as independent predictors of atrial EMD. © 2013, Wiley Periodicals, Inc.

The safety of flecainide treatment of atrial fibrillation

DEFF Research Database (Denmark)

Almroth, H; Andersson, Torben Bech; Fengsrud, E

2011-01-01

To assess the safety of long-term treatment with flecainide in patients with atrial fibrillation (AF), particularly with regard to sudden cardiac death (SCD) and proarrhythmic events.......To assess the safety of long-term treatment with flecainide in patients with atrial fibrillation (AF), particularly with regard to sudden cardiac death (SCD) and proarrhythmic events....

Surgical Ablation of Atrial Fibrillation Using Energy Sources.

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Brick, Alexandre Visconti; Braile, Domingo Marcolino

2015-01-01

Surgical ablation, concomitant with other operations, is an option for treatment in patients with chronic atrial fibrillation. The aim of this study is to present a literature review on surgical ablation of atrial fibrillation in patients undergoing cardiac surgery, considering energy sources and return to sinus rhythm. A comprehensive survey was performed in the literature on surgical ablation of atrial fibrillation considering energy sources, sample size, study type, outcome (early and late), and return to sinus rhythm. Analyzing studies with immediate results (n=5), the percentage of return to sinus rhythm ranged from 73% to 96%, while those with long-term results (n=20) (from 12 months on) ranged from 62% to 97.7%. In both of them, there was subsequent clinical improvement of patients who underwent ablation, regardless of the energy source used. Surgical ablation of atrial fibrillation is essential for the treatment of this arrhythmia. With current technology, it may be minimally invasive, making it mandatory to perform a procedure in an attempt to revert to sinus rhythm in patients requiring heart surgery.

Anomalous muscle bundle in the right atrium; Implication to trans atrial device closure

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Saji Philip

2017-09-01

Full Text Available Intracavitary muscle bands or aberrant bands have been well described in all four chambers of the heart but rarely seen thick muscular band crossing right atrium. We report a case of devisable secundum atrial septal defect with an intra-atrial anomalous muscular band, crossing right atrial wall to the rim of the secundum atrial septal defect warranting surgical closure.

Delayed Onset of Atrial Fibrillation and Ventricular Tachycardia after an Automobile Lightning Strike.

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Drigalla, Dorian; Essler, Shannon E; Stone, C Keith

2017-11-01

Lightning strike is a rare medical emergency. The primary cause of death in lightning strike victims is immediate cardiac arrest. The mortality rate from lightning exposure can be as high as 30%, with up to 70% of patients left with significant morbidity. An 86-year-old male was struck by lightning while driving his vehicle and crashed. On initial emergency medical services evaluation, he was asymptomatic with normal vital signs. During his transport, he lost consciousness several times and was found to be in atrial fibrillation with intermittent runs of ventricular tachycardia during the unconscious periods. In the emergency department, atrial fibrillation persisted and he experienced additional episodes of ventricular tachycardia. He was treated with i.v. amiodarone and admitted to cardiovascular intensive care unit, where he converted to a normal sinus rhythm on the amiodarone drip. He was discharged home without rhythm-control medications and did not have further episodes of dysrhythmias on follow-up visits. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Lightning strikes are one of the most common injuries suffered from natural phenomenon, and short-term mortality ordinarily depends on the cardiac effects. This case demonstrates that the cardiac effects can be multiple, delayed, and recurrent, which compels the emergency physician to be vigilant in the initial evaluation and ongoing observation of patients with lightning injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

Perfil diferencial do administrador do Vale do Rio dos Sinos

OpenAIRE

Lauro Tischer

1999-01-01

As indústrias de calçados da região do Vale do Rio dos Sinos, sempre se destacaram no Brasil e no mundo por produtos reconhecidos internacionalmente, pela quantidade, qualidade e variedade de modelos. Com a globalização da economia e o desenvolvimento tecnológico imperante no mundo industrial, a região começou, rapidamente a ser deslocada de centro produtor de calçados para, quem sabe, centro consumidor de calçados. Quando as empresas começam a ter maus resultados, a culpa recai sempre nos “o...

Alcohol consumption and risk of atrial fibrillation

DEFF Research Database (Denmark)

Tolstrup, Janne Schurmann; Wium-Andersen, Marie Kim; Ørsted, David Dynnes

2016-01-01

BACKGROUND: The aim of this study was to test the hypothesis that alcohol consumption, both observational (self-reported) and estimated by genetic instruments, is associated with a risk of atrial fibrillation and to determine whether people with high cardiovascular risk are more sensitive towards...... alcohol than people with low risk. METHODS: We used data for a total of 88,782 men and women from the Copenhagen City Heart Study 1991-1994 and 2001-2003 and the Copenhagen General Population Study 2003-2010. Information on incident cases of atrial fibrillation was obtained from a validated nationwide...... register. As a measure of alcohol exposure, both self-reported consumption and genetic variations in alcohol metabolizing genes (ADH1B/ADH1C) were used as instrumental variables. The endpoint was admission to hospital for atrial fibrillation as recorded in a validated hospital register. RESULTS: A total...

Vascularização arterial da região do nó sinoatrial em corações suínos: origem, distribuição e quantificação Arterial vascularization of the sinoatrial node in swine hearts: origin, distribution and quantification

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Ana P. Vidotti

2008-02-01

superfície de área (Sv foi de 182 e a superfície de área (S - mm² - foi de 64,3x10(6µm². A estimação da densidade numérica vascular (Nv(vasc, quantidade de vasos por unidade de volume (cm³, foi de 2,19 10-5 e o número total de vasos no órgão (N(vasc, estimado pelo método dissector físico em combinação com a estimativa do número de Euler (Xv, foi de 773,6832 x10-2. A elevada densidade vascular e do número total de vasos na região do nó sinoatrial de suínos sugere a existência de uma complexa e densa rede vascular perinodal, ratificando a importância deste marca-passo pelo seu suprimento sangüíneo.The sinoatrial node, for being topographically installed as the initial component of the conduction system, is responsible for the production of the nervous impulses, which determines the cardiac contraction. There have been made studies related to the node's morphology in order to know the origin, distribution and quantification of the vases in this tissue, however, in spite of the results and quantitative data of the nodal irrigation - arterial vascular conduct and arterial vascular density, at the nodal level - the literature is scarce. With this objective 27 SRD swine hearts, injected with colored resin for macroscopic analysis of the origin and distribution of ANSA (sinoatrial node artery, 3 others injected with watery solution of colloidal coal (dyed nanquim were used, to mark the route of the vases on the node level for stereological analysis. The atrial arteries originated as well from the right coronary artery as from the left one, with predominance of the first (66.66% and 33.33%, respectively. When originated from the right coronary artery, there existed the following branches: AADAM (right cranial medial atrial artery in 14 cases, AADAI (right cranial intermedial atrial artery in 2 cases, and AADAL (right cranial lateral atrial artery in 2 cases. In 9 cases (33.33% the following branches originated from the left coronary artery: 4 through

Atrial Fibrillation and Gastro-Oesophageal Reflux Disease - Controversies and Challenges.

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Floria, Mariana; Barboi, Oana; Rezus, Ciprian; Ambarus, Valentin; Cijevschi-Prelipcean, Cristina; Balan, Gheorghe; Drug, Vasile Liviu

2015-01-01

Atrial fibrillation and gastro-oesophageal reflux are common manifestations in daily practice. The atria and the oesophagus are closely located and have similar nerve innervations. Over the last years, it has been observed that atrial fibrillation development and reflux disease could be related. Atrial fibrillation occurrence could be due to vagal nerve overstimulation. This, in association with vagal nerve-mediated parasympathetic stimulation, has also been observed in patients with gastro-oesophageal reflux. These mechanisms, in addition to inflammation, seem to be implicated in the pathophysiology of both diseases. Despite these associations supported by clinical and experimental studies, this relationship is still considered controversial. This review summarizes critical data regarding the association of gastro-oesophageal reflux and atrial fibrillation as well as their clinical implications.

On the Cultural Legacy of the Cold War: Sino-US Educational Exchange (1949-1990)

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Gu, Ning

2006-01-01

The Cold War affected the Sino-US educational exchange between 1949 and 1990. During those years, preparation for educational exchanges, personal contact and cross-government relations characterized the three periods of the exchanges. However, even though the relationship had developed very fast, it was by no means smooth sailing. These exchanges…

Women Sex Importance in Stroke Patients with Atrial Fibrillation

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Cemile Handan Mısırlı

2014-08-01

Full Text Available OBJECTIVE: It was shown the differences in age, risk factors and treatment between women and men in stroke patients with atrial fibrillation METHODS: The stroke patients with atrial fibrillation who were hospitalized in our department at the last 2 years were seperated into 2 groups of aged above 75 and below 75, investigated with CHADS2 and CHA2DS2VASc scores and looked at the sex differences of women and men. RESULTS: Stroke ratio according to sex was statistically meaningful especially in women above the age of 75. Risc factors also were founded in elderly women and CHA2DS2VASc scores were higher in women than men so more anticoagulan treatment were begun. No differences were shown between sexes at lone atrial fibrillation and no treatment were begun. CONCLUSION: Women with atrial fibrillation had more risk factors, higher stroke rate and higher anticoagulation treatment.

Atrial electrogram interpretation improves after an innovative education program.

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Preston, Julie L; Currey, Judy; Considine, Julie

2015-01-01

To avoid adverse patient outcomes from inappropriate treatment, it is recommended that an atrial electrogram (AEG) be recorded whenever atrial arrhythmias develop in patients after cardiac surgery. However, AEGs are not commonly performed because nurses lack knowledge about differentiating atrial rhythms on AEGs. To investigate whether completing a novel online evidence-based education program on interpreting AEGs would improve critical care nurses' AEG interpretation. Specialized critical care nurses were taught about obtaining and interpreting atrial rhythms on AEGs using a 42-minute online mini-movie. AEG interpretation was assessed pre and two and eight weeks post-intervention. AEG interpretation increased two weeks post intervention and was retained at eight weeks. Some participants used this newly acquired knowledge to interpret arrhythmias that were not taught during the education program. Accurate interpretation of AEGs is an easy skill for specialized critical care nurses to learn via an online education program.

Risk of atrial fibrillation in diabetes mellitus: A nationwide cohort study.

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Pallisgaard, Jannik L; Schjerning, Anne-Marie; Lindhardt, Tommi B; Procida, Kristina; Hansen, Morten L; Torp-Pedersen, Christian; Gislason, Gunnar H

2016-04-01

Diabetes has been associated with atrial fibrillation but the current evidence is conflicting. In particular knowledge regarding young diabetes patients and the risk of developing atrial fibrillation is sparse. The aim of our study was to investigate the risk of atrial fibrillation in patients with diabetes compared to the background population in Denmark. Through Danish nationwide registries we included persons above 18 years of age and without prior atrial fibrillation and/or diabetes from 1996 to 2012. The study cohort was divided into a background population without diabetes and a diabetes group. The absolute risk of developing atrial fibrillation was calculated and Poisson regression models adjusted for sex, age and comorbidities were used to calculate incidence rate ratios of atrial fibrillation. The total study cohort included 5,081,087 persons, 4,827,713 (95%) in the background population and 253,374 (5%) in the diabetes group. Incidence rates of atrial fibrillation per 1000 person years were stratified in four age groups from 18 to 39, 40 to 64, 65 to 74 and 75 to 100 years giving incidence rates (95% confidence intervals) of 0.02 (0.02-0.02), 0.99 (0.98-1.01), 8.89 (8.81-8.98) and 20.0 (19.9-20.2) in the background population and 0.13 (0.09-0.20), 2.10 (2.00-2.20), 8.41 (8.10-8.74) and 20.1 (19.4-20.8) in the diabetes group, respectively. The adjusted incidence rate ratios in the diabetes group with the background population as reference were 2.34 (1.52-3.60), 1.52 (1.47-1.56), 1.20 (1.18-1.23) and 0.99 (0.97-1.01) in the four age groups, respectively. Diabetes is an independent risk factor for developing atrial fibrillation/flutter, most pronounced in young diabetes patients. Routine screening for atrial fibrillation/flutter in diabetes patients might be beneficial and have therapeutic implications, especially in younger diabetes patients. Diabetes increases the risk of developing atrial fibrillation and especially young diabetes patients have a high

Time trends in antithrombotic management of patients with atrial fibrillation treated with coronary stents: Results from TALENT-AF (The internAtionaL stENT - Atrial Fibrillation study) multicenter registry.

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Potter, Brian J; Andò, Giuseppe; Cimmino, Giovanni; Ladeiras-Lopes, Ricardo; Frikah, Zied; Chen, Xin Yue; Virga, Vittorio; Goncalves-Almeida, Joao; Camm, A John; Fox, Keith A A

2018-04-01

Antithrombotic management of patients with atrial fibrillation (AF) requiring percutaneous coronary intervention (PCI) is highly variable; limited evidence-based guidelines exist to influence practice. Patient characteristics and availability of novel drugs may have contributed to practice variability. We undertook an international multicenter retrospective registry of AF patients treated with PCI. The primary measures of interest were antiplatelet and OAC prescriptions at discharge. We compared temporal trends between Prior (2010-2012) and Recent (2013-2015) cohorts and investigated variables associated with OAC prescription. We identified 488 cases (140 Prior, 348 Recent). Median CHADS 2 and HAS-BLED scores were 2 (IQR, 1-3) and 2 (IQR, 2-3). Clinical characteristics were similar between cohorts, with high (85%) prevalence of ACS. More patients in the Recent cohort, compared with Prior, received OAC (56.9% vs 44.3%; P = 0.01) and NOAC (27.3% vs 3.6%; P < 0.01) at baseline. Triple therapy at discharge was not different between the cohorts. Clinical presentation with ACS and consequent use of potent P2Y 12 inhibitors were associated with reduced odds of OAC prescription at discharge (OR: 0.57, P = 0.045 and OR: 0.38, P = 0.023, respectively). Despite little change over time in clinical characteristics of AF patients undergoing PCI, significantly more patients received OAC at presentation. However, triple therapy was not more frequent in the Recent cohort, and ACS presentation was associated with lack of OAC at discharge. We underscore the need for trial evidence and use of updated guidelines to assist clinicians in balancing ischemic and bleeding risks. © 2018 Wiley Periodicals, Inc.

Cardiac ion channels and mechanisms for protection against atrial fibrillation

DEFF Research Database (Denmark)

Grunnet, Morten; Bentzen, Bo Hjorth; Sørensen, Ulrik S

2011-01-01

Atrial fibrillation (AF) is recognised as the most common sustained cardiac arrhythmia in clinical practice. Ongoing drug development is aiming at obtaining atrial specific effects in order to prevent pro-arrhythmic, devastating ventricular effects. In principle, this is possible due to a differe...... to the recent discovery that Ca(2+)-activated small conductance K(+) channels (SK channels) are important for the repolarisation of atrial action potentials. Finally, an overview of current pharmacological treatment of AF is included....

Anticoagulant and Antiplatelet Prescribing Patterns for Patients with Atrial Fibrillation after Percutaneous Coronary Intervention.

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Woods, Erin A; Ackman, Margaret L; Graham, Michelle M; Koshman, Sheri L; Boswell, Rosaleen M; Barry, Arden R

2016-01-01

Current guidelines recommend triple antithrombotic therapy (TAT), defined as acetylsalicylic acid (ASA), clopidogrel, and warfarin, for patients with nonvalvular atrial fibrillation who have undergone percutaneous coronary intervention with stent implantation. The choice of anticoagulant/antiplatelet therapy in this population is ambiguous and complex, and prescribing patterns are not well documented. To characterize local prescribing patterns for anticoagulant/antiplatelet therapy after percutaneous coronary intervention in patients with nonvalvular atrial fibrillation. A chart review was conducted at a single quaternary cardiology centre. Patients with nonvalvular atrial fibrillation were identified via medical records, and those who underwent percutaneous coronary intervention were identified using a local clinical patient registry. Adult inpatients with nonvalvular atrial fibrillation and a CHADS2 score (based on congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke) of 1 or higher who underwent percutaneous coronary intervention from 2011 to 2013 were included. Patients undergoing cardiovascular surgery or transcatheter aortic valve replacement, those with mechanical devices requiring anticoagulation, and those with an allergy to any component of TAT were excluded. Seventy patients were included. The median age was 75 years, and 52 (74%) were men. At discharge, 30 (43%) were receiving TAT and 27 (39%) were receiving dual antiplatelet therapy (clopidogrel and ASA). No patients received the combination of warfarin and clopidogrel. Among those who received TAT, 90% (19 of 21) who received a bare metal stent had a recommended duration of 1 month, and 75% (6 of 8) who received a drug-eluting stent had a recommended duration of 1 year. Direct-acting oral anticoagulants with 2 antiplatelet drugs were prescribed for 9% (6 of 70) of the patients, and 10% (7 of 70) received ticagrelor and ASA with or without warfarin. Overall, the

Oclusão percutânea do apêndice atrial esquerdo com o Amplatzer Cardiac PlugTM na fibrilação atrial

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Márcio José Montenegro

2012-02-01

Full Text Available Fundamento: A fibrilação atrial está associada a acidentes vasculares embólicos que frequentemente resultam em morte ou invalidez. Eficaz na redução desses eventos, a anticoagulação possui várias limitações e vem sendo amplamente subutilizada. Mais de 90% dos trombos identificados nos portadores de fibrilação atrial sem doença valvar se originam no apêndice atrial esquerdo, cuja oclusão é investigada como uma alternativa à anticoagulação. Objetivo: Determinar a viabilidade da oclusão percutânea do apêndice atrial esquerdo em pacientes com alto risco de eventos embólicos e limitações ao uso de anticoagulação. Métodos: Relatamos a experiência inicial com o Amplatzer Cardiac PlugTM (St. Jude Medical Inc., Saint Paul, Estados Unidos em pacientes com fibrilação atrial não valvar. Foram selecionados pacientes com alto risco de tromboembolia, sangramentos maiores e contraindicações ao uso ou grande labilidade na resposta ao anticoagulante. Os procedimentos foram realizados por via percutânea, sob anestesia geral e com ecocardiografia transesofágica. O desfecho primário foi a presença de complicações periprocedimento e o seguimento programado incluiu reavaliação clínica e ecocardiográfica em 30 dias e por contato telefônico após nove meses. Resultados: Nos cinco pacientes selecionados se conseguiu a oclusão do apêndice atrial esquerdo sem complicações periprocedimento. Não houve eventos clínicos no seguimento. Conclusão: Ensaios clínicos controlados são necessários antes que o fechamento percutâneo do apêndice atrial esquerdo constitua uma alternativa à anticoagulação na fibrilação atrial não associada a doença valvar. Mas o dispositivo se mostrou promissor em pacientes com alto risco de embolia e restrições ao uso de anticoagulantes.

Time to implement fitness and reduction of fatness in atrial fibrillation therapy

NARCIS (Netherlands)

Van Gelder, Isabelle C.; Hobbelt, Anne H.; Brugemann, Johan; Rienstra, Michiel

This editorial refers to ‘Self-reported physical activity and major adverse events in patients with atrial fibrillation: a report from the EURObservational Research Programme Pilot Survey on Atrial Fibrillation (EORP-AF) General Registry’ by M. Proietti et al. , doi:10.1093/europace/euw150. Atrial

Decision-making interventions to stop the global atrial fibrillation-related stroke tsunami.

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Cerasuolo, Joshua O; Montero-Odasso, Manuel; Ibañez, Agustin; Doocy, Shannon; Lip, Gregory Yh; Sposato, Luciano A

2017-04-01

Atrial fibrillation affects 33.5 million people worldwide and its prevalence is expected to double by 2050 because of the aging population. Atrial fibrillation confers a 5-fold higher risk of ischemic stroke compared to sinus rhythm. We present our view of the role of shared medical decision-making to combat global underutilization of oral anticoagulation for stroke prevention in atrial fibrillation patients. Oral anticoagulation underuse is widespread as it is present within atrial fibrillation patients of all risk strata and in countries across all income levels. Reasons for oral anticoagulation underuse include but are probably not limited to poor risk stratification, over-interpretation of contraindications, and discordance between physician prescription preferences and actual administration. By comparing a catastrophic event to the consequences of atrial fibrillation related strokes, it may help physicians and patients understand the negative outcomes associated with oral anticoagulation under-utilization and the magnitude to which oral anticoagulations neutralize atrial fibrillation burden.

Assessment of the effect of left atrial cryoablation enhanced by ganglionated plexi ablation in the treatment of atrial fibrillation in patients undergoing open heart surgery.

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Bárta, Jiří; Brát, Radim

2017-08-17

The aim of our study was to investigate, whether enhancement of left atrial cryoablation by ablation of the autonomic nervous system of left atrium leads to influencing the outcomes of surgical treatment of atrial fibrillation in patients with structural heart disease undergoing open-heart surgery. The observed patient file consisted of 100 patients, who have undergone a combined open-heart surgery at our department between July 2012 and December 2014. The patients were indicated for the surgical procedure due to structural heart disease, and suffered from paroxysmal, persistent, or long-standing persistent atrial fibrillation. In all cases, left atrial cryoablation was performed in the extent of isolation of pulmonary veins, box lesion, connecting lesion with mitral annulus, amputation of the left atrial appendage and connecting lesion of the appendage base with left pulmonary veins. Furthermore, 35 of the patients underwent mapping and radiofrequency ablation of ganglionated plexi, together with discision and ablation of the ligament of Marshall (Group GP). A control group was consisted of 65 patients without ganglionated plexi intervention (Group LA). The main primary outcome was establishment and duration of sinus rhythm in the course of one-year follow-up. Evaluation of the number of patients with a normal sinus rhythm in per cent has shown comparable values in both groups (Group GP - 93.75%, Group LA - 86.67%, p = 0.485); comparable results were also observed in patients with normal sinus rhythm without anti-arrhythmic treatment in the 12th month (Group GP - 50%, Group LA - 47%, p = 0.306). We have not observed any relation between the recurrence of atrial fibrillation and the presence of a mitral valve surgery, or between the presence of a mitral and tricuspid valves surgery and between the left atrial diameter > 50 mm. Enhancement of left atrial cryoablation by gangionated plexi ablation did not influence the outcomes of surgical ablation due to

EFFECT OF EXERCISE ON CYCLE LENGTH IN ATRIAL-FLUTTER

NARCIS (Netherlands)

VANDENBERG, MP; CRIJNS, HJGM; SZABO, BM; BROUWER, J; LIE, KI

Objective-To examine the effect of exercise on cycle length in atrial flutter. Patients-15 patients with chronic atrial flutter. Seven patients were taking digoxin and six verapamil; two were not taking medication. Methods-All patients underwent bicycle ergometry. Flutter cycle length was measured

Automatic detection and classification of human epicardial atrial unipolar electrograms

International Nuclear Information System (INIS)

Dubé, B; Vinet, A; Xiong, F; Yin, Y; LeBlanc, A-R; Pagé, P

2009-01-01

This paper describes an unsupervised signal processing method applied to three-channel unipolar electrograms recorded from human atria. These were obtained by epicardial wires sutured on the right and left atria after coronary artery bypass surgery. Atrial (A) and ventricular (V) activations had to be detected and identified on each channel, and gathered across the channels when belonging to the same global event. The algorithm was developed and optimized on a training set of 19 recordings of 5 min. It was assessed on twenty-seven 2 h recordings taken just before the onset of a prolonged atrial fibrillation for a total of 1593697 activations that were validated and classified as normal atrial or ventricular activations (A, V) and premature atrial or ventricular activations (PAA, PVA). 99.93% of the activations were detected, and amongst these, 99.89% of the A and 99.75% of the V activations were correctly labelled. In the subset of the 39705 PAA, 99.83% were detected and 99.3% were correctly classified as A. The false positive rate was 0.37%. In conclusion, a reliable fully automatic detection and classification algorithm was developed that can detect and discriminate A and V activations from atrial recordings. It can provide the time series needed to develop a monitoring system aiming to identify dynamic predictors of forthcoming cardiac events such as postoperative atrial fibrillation

Modular sensor network node

Science.gov (United States)

Davis, Jesse Harper Zehring [Berkeley, CA; Stark, Jr., Douglas Paul; Kershaw, Christopher Patrick [Hayward, CA; Kyker, Ronald Dean [Livermore, CA

2008-06-10

A distributed wireless sensor network node is disclosed. The wireless sensor network node includes a plurality of sensor modules coupled to a system bus and configured to sense a parameter. The parameter may be an object, an event or any other parameter. The node collects data representative of the parameter. The node also includes a communication module coupled to the system bus and configured to allow the node to communicate with other nodes. The node also includes a processing module coupled to the system bus and adapted to receive the data from the sensor module and operable to analyze the data. The node also includes a power module connected to the system bus and operable to generate a regulated voltage.

Resultados da ablação cirúrgica por radiofreqüência da fibrilação atrial crônica Results of the intraoperative radiofrequency ablation of chronic atrial fibrillation

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Carlos Alberto Cordeiro de Abreu Filho

2004-09-01

incisions of the Cox technique have been developed. The purpose of this study is to evaluate the results of intraoperative radiofrequency ablation in the treatment of chronic atrial fibrillation in patients with associated cardiac diseases. METHOD: Between February 2002 and March 2003, 35 consecutive patients with chronic atrial fibrillation were submitted to intraoperative radiofrequency ablation, associated with other surgical procedures. The ages of the patients ranged from 16 to 69 years old (mean 55.4 years old; there were 23 (65.7% female patients. RESULTS: Radiofrequency ablation was associated with surgical treatment of the mitral valve in 29 (82.9% patients and with treatment of atrial septal defect in six (17.1%. There was 1 (2.8% in-hospital death; at the time of hospital discharge 26 patients (76.4% were in sinus rhythm. After a mean follow-up of 11.7 ± 2.8 months, the overall survival rate was 94.2 % and 24 (72.7% patients were in sinus rhythm. CONCLUSION: Intraoperative radiofrequency ablation is a safe and effective technique for the treatment of chronic atrial fibrillation, with satisfactory midterm results in terms of conversion to sinus rhythm.

Electron-beam CT diagnosis of the viscero-atrial heterotaxy syndrome

International Nuclear Information System (INIS)

Yang Youyou; Dai Ruping; Jing Baolian; He Sha; Bai Hua; Li Xiangmin; Zhou Xuhui; Peng Qian; Meng Quanfei

2002-01-01

Objective: To assess the usefulness of electron-beam CT (EBCT) in diagnosis of the viscero-atrial heterotaxy syndrome. Methods: Ten patients with the viscero-atrial heterotaxy syndrome were evaluated. The patients ranged in age from 7 months to 17 years (averaged 9.5 years). Five of the patients underwent EBCT contrast single slice mode while another 5 patients did continuous volume scan obtained from the superior aperture of thorax to the middle part of abdomen. All the patients had both angiocardiogram and echocardiogram, and 6 patients had operative outcomes. Results; (1) Eight patients with right atrial isomerism, bilaterally morphologic right atrial appendages, right lobe dominant symmetric liver, bilaterally epi-arterial bronchi, trilobed lungs, and total anomalous pulmonary venous connectional were clearly detected. Endocardial cushions defect, pulmonary stenosis, right-sided aortic arch and descending aorta were documented in 7 patients. Double outlet of right ventricle was imaged in 6 patients and hiatal hernia in 2 patients. Neither a spleen nor splenulus were found. (2) Two patients with left atrial isomerism, bilaterally morphologic left atrial appendages, left lobe dominant symmetric liver, bilaterally hyparterial bronchi, bilobed lungs, double outlet of right ventricle, pulmonary stenosis, interruption of inferior vena cave, right-sided aortic arch, and descending aorta were documented. Endocardial cushions defect was detected in 1 patient. Multiple spleens were demonstrated in the right upper abdomen in the 2 patients. (3) The number of abnormal observations detected by EBCT was 116, while that done by angiocardiogram and echocardiogram were 65 and 43 respectively. Conclusion: EBCT is a useful tool in the evaluation of patients with the syndrome of viscero-atrial heterotaxia

New risk factors for atrial fibrillation : causes of 'not-so-lone atrial fibrillation'

NARCIS (Netherlands)

Schoonderwoerd, Bas A.; Smit, Marcelle D.; Pen, Lucas; Van Gelder, Isabelle C.

Atrial fibrillation (AF) is a prevalent arrhythmia in patients with cardiovascular disease. The classical risk factors for developing AF include hypertension, valvular disease, (ischaemic) cardiomyopathy, diabetes mellitus, and thyroid disease. In some patients with AF, no underlying

Características ultra-estruturais do nó sinoatrial de rato Wistar Superstructural features of the wistar strain male rats' sinoatrial node (SAN

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Carlos Alberto Mandarim de Lacerda

2002-04-01

Full Text Available As características ultra-estruturais do nó sinoatrial (NSA de 5 ratos machos da variedade Wistar, com 3 meses de idade, foram estudadas por meio de microscopia eletrônica de transmissão (MET. Fragmento pequeno, contendo a região do NSA e área adjacente do átrio direito do coração, foi retirado e fixado em glutaraldeído 2,5% e processado de acordo com técnica convencional para MET. A morfologia do nó sinoatrial de ratos é semelhante a de outros mamíferos. O NSA é uma estrutura anatômica independente do miocárdio atrial, constituído por células típicas (miócitos nodais, células de transição e, principalmente, células nodais imersos em matriz extracelular, na qual predominam fibras colágenas, fibroblastos e nervosThe superstructural features of five Wistar strain male rats' sinoatrial node (SAN at 3-mo-old were studied through transmission electron microscopy (TEM. Small fragments with the regions containing the SAN were cut off, fixed in glutaraldehyde 2.5% and processed according to the conventional technique for TEM. The morphology of the sinoatrial node of the rats is similar as found in other mammals. The SAN is an independent anatomic structure of the atrial myocardial, constituted of typical cells (nodal myocytes, transition cells and nodal cells principally immersed in the extra cellular matrix where collagen fibers, fibroblasts and nerve predominate

Atrial Function in Patients with Breast Cancer After Treatment with Anthracyclines

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Yalin Tolga Yaylali

Full Text Available Abstract Background: Atrial electromechanical delay (EMD is used to predict atrial fibrillation, measured by echocardiography. Objectives: The aim of this study was to assess atrial EMD and mechanical function after anthracycline-containing chemotherapy. Methods: Fifty-three patients with breast cancer (48 ± 8 years old who received 240 mg/m2of Adriamycin, 2400 mg/m2 of cyclophosphamide, and 960 mg/m2 of paclitaxel were included in this retrospective study, as were 42 healthy subjects (47 ± 9 years old. Echocardiographic measurements were performed 11 ± 7 months (median 9 months after treatment with anthracyclines. Results: Left intra-atrial EMD (11.4 ± 6.0 vs. 8.1 ± 4.9, p=0.008 and inter-atrial EMD (19.7 ± 7.4 vs. 14.7 ± 6.5, p=0.001 were prolonged; LA passive emptying volume and fraction were decreased (p=0.0001 and p=0.0001; LA active emptying volume and fraction were increased (p=0.0001 and p=0.0001; Mitral A velocity (0.8 ± 0.2 vs. 0.6 ± 0.2, p=0.0001 and mitral E-wave deceleration time (201.2 ± 35.6 vs. 163.7 ± 21.8, p=0.0001 were increased; Mitral E/A ratio (1.0 ± 0.3 vs. 1.3 ± 0.3, p=0.0001 and mitral Em (0.09 ± 0.03 vs. 0.11 ± 0.03, p=0.001 were decreased; Mitral Am (0.11 ± 0.02 vs. 0.09 ± 0.02, p=0.0001 and mitral E/Em ratio (8.8 ± 3.2 vs. 7.6 ± 2.6, p=0.017 were increased in the patients. Conclusions: In patients with breast cancer after anthracycline therapy: Left intra-atrial, inter-atrial electromechanical intervals were prolonged. Diastolic function was impaired. Impaired left ventricular relaxation and left atrial electrical conduction could be contributing to the development of atrial arrhythmias.

Aorto-right atrial fistula after Bentall repair.

Science.gov (United States)

Howard, Charles E; Velasco, Carlos E; Roullard, Christina P; Rafael, Aldo

2017-07-01

We describe a man with the Marfan syndrome and a prior ascending aortic aneurysm resection who presented with knee pain and concern of endocarditis. Transesophageal echocardiogram showed no vegetations, and computed tomography angiogram of the heart showed a possible pseudoaneurysm. Cardiac catheterization and aortogram revealed the diagnosis of an aorto-right atrial fistula, which was then operatively repaired. This case highlights the role that cardiac catheterization with aortogram can play in the detection of aorto-atrial fistula.

Percutaneous closure of the left atrial appendage with Watchman device: An option for patients with atrial fibrilation and high risk of bleeding with anticoagulation

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Sénior, Juan

2015-07-01

Full Text Available Atrial fibrillation is the most common arrhythmia found in clinical practice, with a population prevalence of 1% to 2%. Anticoagulation remains a fundamental part of treatment for the prevention of cerebrovascular events (stroke, but it is contraindicated in approximately 20% of patients. We report a case of non-valvular atrial fibrillation with high-risk score for stroke, a history of intracerebral bleeding, and very high risk of bleeding with long-term anticoagulation. Percutaneous closure of the left atrial appendage with the Watchman device was performed successfully without complications.

Screening for Atrial Fibrillation

DEFF Research Database (Denmark)

Freedman, Ben; Camm, John; Calkins, Hugh

2017-01-01

Approximately 10% of ischemic strokes are associated with atrial fibrillation (AF) first diagnosed at the time of stroke. Detecting asymptomatic AF would provide an opportunity to prevent these strokes by instituting appropriate anticoagulation. The AF-SCREEN international collaboration was formed...

Atrial Cardiomyopathy: A Useful Notion in Cardiac Disease Management or a Passing Fad?

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Guichard, Jean-Baptiste; Nattel, Stanley

2017-08-08

The term atrial cardiomyopathy, which has been used sporadically in the medical literature, was recently the subject of a detailed Consensus Document prepared by representatives of the European Heart Rhythm Association, Heart Rhythm Society, Asia-Pacific Heart Rhythm Society, and Sociedad Latinoamericana de Estimulación Cardiaca y Electrofisiología. They discussed aspects of the definition, histopathology, atrial-specific physiology, atrial pathology, impact on arrhythmia occurrence, imaging, mapping, and ablation. Here, the authors consider critically the added clinical value of this concept and its meaningfulness. They review evidence implicating atrial cardiomyopathy as an independent contributor to the risk of stroke associated with atrial fibrillation and as a determinant of arrhythmia progression. The issue of classification is considered and the authors discuss how atrial cardiomyopathic properties might guide stroke prevention, rhythm maintenance, and rate control in atrial fibrillation. Carefully designed clinical trials are needed to evaluate these potential applications, and will ultimately define the value of this terminology. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Oclusão do apêndice atrial esquerdo com o Amplatzer Cardiac Plug em pacientes com fibrilação atrial Left atrial appendage closure with the Amplatzer Cardiac Plug in patients with atrial fibrillation

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Ênio Eduardo Guérios

2012-06-01

Full Text Available FUNDAMENTO: A oclusão percutânea do apêndice atrial esquerdo (OAAE surgiu como alternativa à anticoagulação oral (AO para prevenção do acidente vascular cerebral (AVC em pacientes com fibrilação atrial não-valvular (FANV. OBJETIVO: Relatar os resultados imediatos e o seguimento clínico de pacientes submetidos a OAAE com o Amplatzer Cardiac Plug (ACP em um único centro de referência. MÉTODOS: Oitenta e seis pacientes consecutivos com FANV, contra-indicação à AO e escore CHADS2= 2,6±1,2 foram submetidos a OAAE com implante de ACP. Realizou-se seguimento clínico e ecocardiográfico no mínimo 4 meses após o implante. RESULTADOS: Todos os implantes foram guiados apenas por angiografia. O sucesso do procedimento foi de 99% (1 insucesso por tamponamento cardíaco e consequente suspensão da OAAE. Houve 4 complicações maiores (o tamponamento já referido, 2 AVCs transitórios e uma embolização com retirada percutânea da prótese e duas menores (um derrame pericárdico sem tamponamento e uma pequena comunicação interatrial evidenciada no seguimento. Houve 1 óbito hospitalar após 6 dias, não relacionado à intervenção. Todos os outros pacientes receberam alta sem AO. Após seguimento de 25,9 pacientes-ano (69 pacientes não houve AVCs nem embolizações tardias de próteses. O AAE estava completamente ocluído em 97% dos casos. Seis pacientes apresentaram evidência de trombo sobre a prótese, que desapareceram após reinstituição de AO por 3 meses. CONCLUSÃO: OAAE se associa a um alto índice de sucesso, um índice aceitável de complicações e resultados promissores a médio prazo, podendo ser considerada uma alternativa válida à OA na prevenção do AVC em pacientes com FANV.BACKGROUND: Percutaneous left atrial appendage closure (LAAC has emerged as an alternative to oral anticoagulation (OA for prevention of thromboembolic stroke in patients with non-valvular atrial fibrillation (NVAF. OBJECTIVE: To describe the

Trends in oral anticoagulant choice for acute stroke patients with nonvalvular atrial fibrillation in Japan: The SAMURAI‐NVAF Study

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Arihiro, Shoji; Todo, Kenichi; Yamagami, Hiroshi; Kimura, Kazumi; Furui, Eisuke; Terasaki, Tadashi; Shiokawa, Yoshiaki; Kamiyama, Kenji; Takizawa, Shunya; Okuda, Satoshi; Okada, Yasushi; Kameda, Tomoaki; Nagakane, Yoshinari; Hasegawa, Yasuhiro; Mochizuki, Hiroshi; Ito, Yasuhiro; Nakashima, Takahiro; Takamatsu, Kazuhiro; Nishiyama, Kazutoshi; Kario, Kazuomi; Sato, Shoichiro; Koga, Masatoshi; Nagatsuka, K; Minematsu, K; Nakagawara, J; Akiyama, H; Shibazaki, K; Maeda, K; Shibuya, S; Yoshimura, S; Endo, K; Miyagi, T; Osaki, M; Kobayashi, J; Okata, T; Tanaka, E; Sakamoto, Y; Takizawa, H; Takasugi, J; Tokunaga, K; Homma, K; Kinoshita, N; Matsuki, T; Higashida, K; Shiozawa, M; Kanai, H; Uehara, S

2015-01-01

Background Large clinical trials are lack of data on non‐vitamin K antagonist oral anticoagulants for acute stroke patients. Aim To evaluate the choice of oral anticoagulants at acute hospital discharge in stroke patients with nonvalvular atrial fibrillation and clarify the underlying characteristics potentially affecting that choice using the multicenter Stroke Acute Management with Urgent Risk‐factor Assessment and Improvement‐NVAF registry (ClinicalTrials.gov NCT01581502). Method The study included 1192 acute ischemic stroke/transient ischemic attack patients with nonvalvular atrial fibrillation (527 women, 77·7 ± 9·9 years old) between September 2011 and March 2014, during which three nonvitamin K antagonist oral anticoagulant oral anticoagulants were approved for clinical use. Oral anticoagulant choice at hospital discharge (median 23‐day stay) was assessed. Results Warfarin was chosen for 650 patients, dabigatran for 203, rivaroxaban for 238, and apixaban for 25. Over the three 10‐month observation periods, patients taking warfarin gradually decreased to 46·5% and those taking nonvitamin K antagonist oral anticoagulants increased to 48·0%. As compared with warfarin users, patients taking nonvitamin K antagonist oral anticoagulants included more men, were younger, more frequently had small infarcts, and had lower scores for poststroke CHADS 2, CHA 2 DS 2‐VASc, and HAS‐BLED, admission National Institutes of Health stroke scale, and discharge modified Rankin Scale. Nonvitamin K antagonist oral anticoagulants were started at a median of four‐days after stroke onset without early intracranial hemorrhage. Patients starting nonvitamin K antagonist oral anticoagulants earlier had smaller infarcts and lower scores for the admission National Institutes of Health stroke scale and the discharge modified Rankin Scale than those starting later. Choice of nonvitamin K antagonist oral anticoagulants was independently associated with 20‐day or

Pacemaker implantation after catheter ablation for atrial fibrillation.

Science.gov (United States)

Deshmukh, Abhishek J; Yao, Xiaoxi; Schilz, Stephanie; Van Houten, Holly; Sangaralingham, Lindsey R; Asirvatham, Samuel J; Friedman, Paul A; Packer, Douglas L; Noseworthy, Peter A

2016-01-01

Sinus node dysfunction requiring pacemaker implantation is commonly associated with atrial fibrillation (AF), but may not be clinically apparent until restoration of sinus rhythm with ablation or cardioversion. We sought to determine frequency, time course, and predictors for pacemaker implantation after catheter ablation, and to compare the overall rates to a matched cardioversion cohort. We conducted a retrospective analysis using a large US commercial insurance database and identified 12,158 AF patients who underwent catheter ablation between January 1, 2005 and December 31, 2012. Over an average of 2.4 years of follow-up, 5.6 % of the patients underwent pacemaker implantation. Using the Cox proportional hazards models, we found that risk of risks of pacemaker implantation was associated with older age (50-64 and ≥65 versus pacemaker implantation between ablation patients and propensity score (PS)-matched cardioversion groups (3.5 versus. 4.1 % at 1 year and 8.8 versus 8.3 % at 5 years). Overall, pacemaker implantation occurs in about 1/28 patients within 1 year of catheter ablation. The overall implantation rate decreased between 2005 and 2012. Furthermore, the risk after ablation is similar to cardioversion, suggesting that patients require pacing due to a common underlying electrophysiologic substrate, rather than the ablation itself.

TRIF promotes angiotensin II-induced cross-talk between fibroblasts and macrophages in atrial fibrosis

Energy Technology Data Exchange (ETDEWEB)

Chen, Xiao-Qing; Zhang, Dao-Liang [Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai (China); Zhang, Ming-Jian; Guo, Meng; Zhan, Yang-Yang; Liu, Fang [National Key Laboratory of Medical Immunology, Second Military Medical University, Shanghai (China); Jiang, Wei-Feng; Zhou, Li [Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai (China); Zhao, Liang, E-mail: zhaol_zg@163.com [Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai (China); Wang, Quan-Xing, E-mail: wqxejd@126.com [National Key Laboratory of Medical Immunology, Second Military Medical University, Shanghai (China); Liu, Xu, E-mail: liuxu_xk@163.com [Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai (China)

2015-08-14

Aims: Atrial fibroblasts and macrophages have long been thought to participate in atrial fibrillation (AF). However, which specific mediator may regulate the interaction between them remains unclear. Methods and results: We provided the evidence for the involvement of Toll/IL-1 receptor domain-containing adaptor inducing IFN-β (TRIF), an important inflammation-related molecule, in the pathophysiology of AF. Patients with AF showed higher levels of angiotensin II (AngII) and TRIF expression and larger number of macrophages infiltration in left atria appendage than individuals with sinus rhythm (SR). In the cell study, AngII induced chemokines expressions in mouse atrial fibroblasts and AngII-stimulated atrial fibroblasts induced the chemotaxis of macrophages, which were reduced by losartan and TRIF siRNA. Meanwhile, AngII-stimulated atrial fibroblasts proliferation was enhanced by macrophages. Conclusions: Our data demonstrated that TRIF may be a crucial factor promoting the interaction between atrial fibroblasts and macrophages, leading to atrial fibrosis. - Highlights: • Compared with SR, AF showed higher TRIF expression in left atrial appendage. • TRIF siRNA reversed macrophage chemotaxis induced by AngII-treated fibroblast. • TRIF siRNA reversed chemokines expressions induced by AngII in fibroblast. • AngII-stimulated atrial fibroblast proliferation was enhanced by macrophage.

TRIF promotes angiotensin II-induced cross-talk between fibroblasts and macrophages in atrial fibrosis

International Nuclear Information System (INIS)

Chen, Xiao-Qing; Zhang, Dao-Liang; Zhang, Ming-Jian; Guo, Meng; Zhan, Yang-Yang; Liu, Fang; Jiang, Wei-Feng; Zhou, Li; Zhao, Liang; Wang, Quan-Xing; Liu, Xu

2015-01-01

Aims: Atrial fibroblasts and macrophages have long been thought to participate in atrial fibrillation (AF). However, which specific mediator may regulate the interaction between them remains unclear. Methods and results: We provided the evidence for the involvement of Toll/IL-1 receptor domain-containing adaptor inducing IFN-β (TRIF), an important inflammation-related molecule, in the pathophysiology of AF. Patients with AF showed higher levels of angiotensin II (AngII) and TRIF expression and larger number of macrophages infiltration in left atria appendage than individuals with sinus rhythm (SR). In the cell study, AngII induced chemokines expressions in mouse atrial fibroblasts and AngII-stimulated atrial fibroblasts induced the chemotaxis of macrophages, which were reduced by losartan and TRIF siRNA. Meanwhile, AngII-stimulated atrial fibroblasts proliferation was enhanced by macrophages. Conclusions: Our data demonstrated that TRIF may be a crucial factor promoting the interaction between atrial fibroblasts and macrophages, leading to atrial fibrosis. - Highlights: • Compared with SR, AF showed higher TRIF expression in left atrial appendage. • TRIF siRNA reversed macrophage chemotaxis induced by AngII-treated fibroblast. • TRIF siRNA reversed chemokines expressions induced by AngII in fibroblast. • AngII-stimulated atrial fibroblast proliferation was enhanced by macrophage

Sentinel Node Biopsy Alone versus Completion Axillary Node Dissection in Node Positive Breast Cancer: Systematic Review and Meta-Analysis

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Rachna Ram

2014-01-01

Full Text Available Introduction. There has been recent interest in validity of completion axillary node dissection after a positive sentinel node. This systematic review aims to ascertain if sentinel lymph node dissection alone was noninferior to axillary lymph node dissection for breast cancer patients who have a positive sentinel node. Method. A systematic review of the electronic databases Embase, MEDLINE, and Cochrane Register of Controlled Trials was carried out. Only randomised trials that had patients with positive sentinel node as the study sample were included in the meta-analysis using the reported hazard ratios with a fixed effect model. Results. Three randomised controlled trials and five retrospective studies were identified. The pooled effect for overall survival was HR 0.94, 95% CI [0.79, 1.19], and for disease free survival was HR 0.83, 95% CI [0.60, 1.14]. The reported rates for locoregional recurrence were similar in both groups. The surgical morbidity was found to be significantly more in patients who had underwent axillary dissection. Conclusion. Amongst patients with micrometastasis in the sentinel node, no further axillary dissection is necessary. For patients with macrometastasis in the sentinel node, it is reasonable to consider omitting axillary dissection to avoid the morbidity of the procedure.

LEFT ATRIAL FUNCTION: MODERN ASSESSMENT METHODS AND CLINICAL SIGNIFICANCE

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E. N. Pavlyukova

2017-01-01

Full Text Available Assessment of the left atrial (LA function is important aspect of comprehensive cardiovascular system estimation. Many cardiac diseases make an impact to LA work either by direct affect on myocardium or hemodynamic condition changing. It is considered, LA and left ventricle diastolic pressure is interrelated, thus without mitral valve disease LA expanding is a sign of LV filling pressure augmentation. Examination of LA size and function by analysis of atrial reservoir, conduit, and booster pump can predict cardiovascular outcomes in patients with cardiomyopathy, ischemic heart disease and valvular heart disease. The last two decades gave new technologies to accurate and comprehensive LA mechanics estimation, in the first place related to tissue Doppler imaging. Atrial strain and strain rate obtained using two-dimensional speckle-tracking echocardiography have proved to be feasible and reproducible techniques to evaluate LA mechanics.In physiological settings, LA is a highly expandable chamber with relatively low pressures. However in the presence of acute and chronic injury, LA wall stretches. LA stretching is a hallmark of structure changing with myocardial fibrosis and has influence on LA strain and strain rate. LA strain estimation could be useful in the prediction of sinus rhythm restoration and maintenance after cardioversion and catheter ablation. Low values of global longitudinal LA strain indicate irreversible LA remodeling and are related to the atrial fibrillation progression from paroxysmal to permanent forms. The most interesting in these circumstances is the potential contribution of echocardiography to thromboembolic risk stratification in atrial fibrillation and invasive procedures such as atrial ablation. Therefore, at present, the main task is to understand the ways of clinical application of data  obtained during the LA study.

Atrial fibrillation and risk of stroke

DEFF Research Database (Denmark)

Christiansen, Christine Benn; Gerds, Thomas A.; Olesen, Jonas Bjerring

2016-01-01

AIM: Although the relation between stroke risk factors and stroke in patients with atrial fibrillation (AF) has been extensively examined, only few studies have explored the association of AF and the risk of ischaemic stroke/systemic thromboembolism/transient ischaemic attack (stroke.......5-10.6), and 15.4% (14.5-16.4), respectively. CONCLUSIONS: Stroke/TE/TIA risk was particularly increased when prior stroke/TE/TIA was present. Atrial fibrillation is associated with an increase in risk of stroke/TE/TIA in the absence of other risk factors but only a moderate increase in risk when other risk...

Initiation of anticoagulation in atrial fibrillation

DEFF Research Database (Denmark)

Gundlund, A.; Staerk, L.; Fosbøl, E. L.

2017-01-01

Background: The use of non-vitamin K antagonist oral anticoagulants (NOACs) for stroke prophylaxis in atrial fibrillation (AF) is increasing rapidly. We compared characteristics of AF patients initiated on NOACs versus vitamin K antagonists (VKAs). Methods: Using Danish nationwide registry data, we...... compared with a VKA [odds ratio (OR) 1.35, 95% confidence interval (CI) 1.28–1.43]. By contrast, patients with a history of myocardial infarction were less likely to be initiated on a NOAC compared with a VKA (OR 0.72, 95% CI 0.67–0.77). Conclusions: Atrial fibrillation patients who were initiated...

Intracellular Calcium Dynamics and Autonomic Stimulation in Atrial Fibrillation: Mechanisms and Implications

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Chung-Chuan Chou, MD

2008-01-01

Full Text Available While atrial fibrillation is characterized by the co-existence of multiple activation waves within the atria, rapid activations in the pulmonary veins play an important role for the initiation and maintenance of atrial fibrillation. In addition to reentry, non-reentrant mechanisms resulting from abnormal intracellular calcium handling and intracellular calcium overload can also be responsible for these rapid activations in the pulmonary veins. Meanwhile, alterations of autonomic tone, involving both the sympathetic and parasympathetic nervous system, have been implicated in initiating paroxysmal atrial fibrillation. But the effectiveness of autonomic modulation as an adjunctive therapeutic strategy to catheter ablation of atrial fibrillation has been inconsistent. The interactions between the autonomic nervous system and atrial fibrillation are more complex than currently understood and further mechanistic and clinical studies are warranted.

Controlling data transfers from an origin compute node to a target compute node

Science.gov (United States)

Archer, Charles J [Rochester, MN; Blocksome, Michael A [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian E [Rochester, MN

2011-06-21

Methods, apparatus, and products are disclosed for controlling data transfers from an origin compute node to a target compute node that include: receiving, by an application messaging module on the target compute node, an indication of a data transfer from an origin compute node to the target compute node; and administering, by the application messaging module on the target compute node, the data transfer using one or more messaging primitives of a system messaging module in dependence upon the indication.

Acute Pulmonary Edema Caused by a Giant Atrial Myxoma

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Andrea Fisicaro

2013-01-01

Full Text Available Atrial myxoma is the most common primary cardiac tumor. Its clinical presentation spreads from asymptomatic incidental mass to serious life-threatening cardiovascular complications. We report the case of a 44-year-old man with evening fever and worsening dyspnea in the last weeks, admitted to our hospital for acute pulmonary edema. The cardiac auscultation was very suspicious for mitral valve stenosis, but the echocardiography revealed a huge atrial mass with a diastolic prolapse into mitral valve orifice causing an extremely high transmitral gradient pressure. Awareness of this uncommon acute presentation of atrial myxoma is necessary for timely diagnosis and prompt surgical intervention.

Pulmonary edema following transcatheter closure of atrial septal defect

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Keerthi Chigurupati

2015-01-01

Full Text Available We describe an incident of development of acute pulmonary edema after the device closure of a secundum atrial septal defect in a 52-year-old lady, which was treated with inotropes, diuretics and artificial ventilation. Possibility of acute left ventricular dysfunction should be considered after the defect closure in the middle-aged patients as the left ventricular compliance may be reduced due to increased elastic stiffness and diastolic dysfunction. Baseline left atrial pressure may be > 10 mmHg in these patients. Associated risk factors for the left ventricular dysfunction are a large Qp:Qs ratio, systemic hypertension, severe pulmonary hypertension and paroxysmal atrial fibrillation.

Protocol for multiple node network

Science.gov (United States)

Kirkham, Harold (Inventor)

1995-01-01

The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs an antibody recognition message termination process performed by all remote nodes and a remote node polling process performed by other nodes which are master units controlling remote nodes in respective zones of the network assigned to respective master nodes. Each remote node repeats only those messages originated in the local zone, to provide isolation among the master nodes.

Sentinel node biopsy before neoadjuvant chemotherapy spares breast cancer patients axillary lymph node dissection.

Science.gov (United States)

van Rijk, Maartje C; Nieweg, Omgo E; Rutgers, Emiel J T; Oldenburg, Hester S A; Olmos, Renato Valdés; Hoefnagel, Cornelis A; Kroon, Bin B R

2006-04-01

Neoadjuvant chemotherapy in breast cancer patients is a valuable method to determine the efficacy of chemotherapy and potentially downsize the primary tumor, which facilitates breast-conserving therapy. In 18 studies published about sentinel node biopsy after neoadjuvant chemotherapy, the sentinel node was identified in on average 89%, and the false-negative rate was on average 10%. Because of these mediocre results, no author dares to omit axillary clearance just yet. In our institute, sentinel lymph node biopsy is performed before neoadjuvant chemotherapy. The aim of this study was to evaluate our experience with this approach. Sentinel node biopsy was performed before neoadjuvant chemotherapy in 25 T2N0 patients by using lymphoscintigraphy, a gamma ray detection probe, and patent blue dye. Axillary lymph node dissection was performed after chemotherapy if the sentinel node contained metastases. Ten patients had a tumor-positive axillary sentinel node, and one patient had an involved lateral intramammary node. Four patients had additional involved nodes in the completion lymph node dissection specimen. The other 14 patients (56%) had a tumor-negative sentinel node and did not undergo axillary lymph node dissection. No recurrences have been observed after a median follow-up of 18 months. Fourteen (56%) of the 25 patients were spared axillary lymph node dissection when the sentinel node was found to be disease free. Performing sentinel node biopsy before neoadjuvant chemotherapy seems successful and reliable in patients with T2N0 breast cancer.

Managing atrial fibrillation in the elderly: critical appraisal of dronedarone

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Trigo P

2011-12-01

Full Text Available Paula Trigo, Gregory W FischerDepartment of Anesthesiology, Mount Sinai School of Medicine, New York, NY, USAAbstract: Atrial fibrillation is the most commonly seen arrhythmia in the geriatric population and is associated with increased cardiovascular morbidity and mortality. Treatment of the elderly with atrial fibrillation remains challenging for physicians, because this unique subpopulation is characterized by multiple comorbidities requiring chronic use of numerous medications, which can potentially lead to severe drug interactions. Furthermore, age-related changes in the cardiovascular system as well as other physiological changes result in altered drug pharmacokinetics. Dronedarone is a new drug recently approved for the treatment of arrhythmias, such as atrial fibrillation and/or atrial flutter. Dronedarone is a benzofuran amiodarone analog which lacks the iodine moiety and contains a methane sulfonyl group that decreases its lipophilicity. These differences in chemical structure are responsible for making dronedarone less toxic than amiodarone which, in turn, results in fewer side effects. Adverse events for dronedarone include gastrointestinal side effects and rash. No dosage adjustments are required for patients with renal impairment. However, the use of dronedarone is contraindicated in the presence of severe hepatic dysfunction.Keywords: atrial fibrillation, elderly, antiarrhythmic agents, amiodarone, dronedarone

Clinical Differences between Subtypes of Atrial Fibrillation and Flutter: Cross-Sectional Registry of 407 Patients

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Eduardo Dytz Almeida

2015-01-01

Full Text Available Introduction: Atrial fibrillation and atrial flutter account for one third of hospitalizations due to arrhythmias, determining great social and economic impacts. In Brazil, data on hospital care of these patients is scarce. Objective: To investigate the arrhythmia subtype of atrial fibrillation and flutter patients in the emergency setting and compare the clinical profile, thromboembolic risk and anticoagulants use. Methods: Cross-sectional retrospective study, with data collection from medical records of every patient treated for atrial fibrillation and flutter in the emergency department of Instituto de Cardiologia do Rio Grande do Sul during the first trimester of 2012. Results: We included 407 patients (356 had atrial fibrillation and 51 had flutter. Patients with paroxysmal atrial fibrillation were in average 5 years younger than those with persistent atrial fibrillation. Compared to paroxysmal atrial fibrillation patients, those with persistent atrial fibrillation and flutter had larger atrial diameter (48.6 ± 7.2 vs. 47.2 ± 6.2 vs. 42.3 ± 6.4; p < 0.01 and lower left ventricular ejection fraction (66.8 ± 11 vs. 53.9 ± 17 vs. 57.4 ± 16; p < 0.01. The prevalence of stroke and heart failure was higher in persistent atrial fibrillation and flutter patients. Those with paroxysmal atrial fibrillation and flutter had higher prevalence of CHADS2 score of zero when compared to those with persistent atrial fibrillation (27.8% vs. 18% vs. 4.9%; p < 0.01. The prevalence of anticoagulation in patients with CHA2DS2-Vasc ≤ 2 was 40%. Conclusions: The population in our registry was similar in its comorbidities and demographic profile to those of North American and European registries. Despite the high thromboembolic risk, the use of anticoagulants was low, revealing difficulties for incorporating guideline recommendations. Public health strategies should be adopted in order to improve these rates.

Right atrial volume calculated by multi-detector computed tomography. Useful predictor of atrial fibrillation recurrence after pulmonary vein catheter ablation

International Nuclear Information System (INIS)

Kaneko, Kyouichi; Akutsu, Yasushi; Kodama, Yusuke

2010-01-01

We investigated whether right atrial (RA) volume could be used to predict the recurrence of atrial fibrillation (AF) after pulmonary vein catheter ablation (CA). We evaluated 65 patients with paroxysmal AF (mean age, 60+10 years, 81.5% male) and normal volunteers (57±14 years, 41.7% male). Sixty-four-slice multi-detector computed tomography was performed for left atrial (LA) and RA volume estimations before CA. The recurrence of AF was assessed for 6 months after the ablation. Both left and right atrial volumes were larger in the AF patients than the normal volunteers (LA: 99.7+33.2 ml vs. 59.7+17.4 ml; RA: 82.9+35.7 ml vs. 43.9+12 ml; P 100 ml) for predicting the recurrence of AF was 81.3% in 13 of 16 patients with AF recurrence, and the specificity was 69.4% in 34 of 49 patients without recurrence. The sensitivity with large RA volumes (>87 ml) was 81.3% in 13 of 16 patients with AF recurrence, and the specificity was 75.5% in 37 of 49 patients without recurrence. RA volume is a useful predictor of the recurrence of AF, similar to LA volume. (author)

A Case of Atrial Tachycardia Circulating around a Left Atrial Roof Scar with Diabetes Mellitus and Renal Failure on Hemodialysis

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Naoko Hijioka

2016-01-01

Full Text Available Introduction. Little is known about the effects of volume change by hemodialysis (HD and mechanical stress caused by an anatomical structure being in contact with the left atrium on the progression of atrial remodeling. We experienced a case of atrial tachycardia (AT in a patient who had left atrial (LA scarring at the LA roof and a low-voltage area with slow conduction around the LA scar as components of AT circuit. Here, we present the conceivable hypothesis of the LA scar and the low-voltage area formation. Our concept can be useful in developing a strategy for ablation in a patient with chronic renal failure (CRF on HD. Case Report. A 65-year-old man with CRF on HD was referred for AT ablation. Three-dimensional electroanatomical mapping revealed that the AT conducted around an LA scar in a counterclockwise fashion. There was a slow conduction area at the superior side of the LA scar, where the AT was terminated during the ablation. Computed tomography indicated a close relationship between the LA and the anatomical structures (ascending aorta and pulmonary artery. Conclusion. Volume change by HD and close contact of anatomical structures to the LA can promote atrial remodeling, resulting in AT occurrence.

Left atrial systolic force in hypertensive patients with left ventricular hypertrophy: the LIFE study

DEFF Research Database (Denmark)

Chinali, M.; Simone, G. de; Wachtell, K.

2008-01-01

In hypertensive patients without prevalent cardiovascular disease, enhanced left atrial systolic force is associated with left ventricular hypertrophy and increased preload. It also predicts cardiovascular events in a population with high prevalence of obesity. Relations between left atrial...... systolic force and left ventricular geometry and function have not been investigated in high-risk hypertrophic hypertensive patients. Participants in the Losartan Intervention For Endpoint reduction in hypertension echocardiography substudy without prevalent cardiovascular disease or atrial fibrillation (n...... = 567) underwent standard Doppler echocardiography. Left atrial systolic force was obtained from the mitral orifice area and Doppler mitral peak A velocity. Patients were divided into groups with normal or increased left atrial systolic force (>14.33 kdyn). Left atrial systolic force was high in 297...

The immediate future for the medical treatment of atrial fibrillation

DEFF Research Database (Denmark)

Pedersen, Ole Dyg; Brendorp, Bente; Køber, Lars

2002-01-01

) the rhythm causes loss of atrioventricular synchrony, which reduces diastolic filling and may lead to heart failure; and iii) atrial contraction is lost leading to stagnant blood that again may lead to atrial thrombi and peripheral embolism. Thus, the treatment of atrial fibrillation is focused...... on the maintenance of sinus rhythm, rate control and prevention of embolism. For the maintenance of sinus rhythm, all drugs under current development are potassium channel blockers; the so-called class III anti-arrhythmic drugs. Those which have been further investigated appear to be valuable for maintenance...

New Procedure for Treatment of Atrial Fibrillation in Patients with Valvular Heart Disease

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Naser Safaie

2010-10-01

Full Text Available Patients with valvular heart disease suffer from atrial fibrillation for more than 12 months after valve surgery and have a low probability of remaining in sinus rhythm. We performed an intra-operative procedure similar to surgical maze ІІІ procedure for conversion of this arrhythmia to sinus rhythm. We did this study to evaluate the efficacy of this procedure to restore the sinus rhythm in patients with valvular heart disease. 28 patients with valvular heart disease and chronic persistent atrial fibrillation underwent different combinations of valve surgery and concomitant reduction of left and right atrial size and resection of both atrial auricles in Shahid Madani cardiothoracic center from September 2004 to October 2008. The procedure for atrial fibrillation treatment was performed with cardiopulmonary bypass and after mitral valve replacement. There was one in-hospital death postoperatively because of respiratory failure, but no other complication till 6 months after the operation. Out of 28 patients, 23 were in sinus rhythm one week after the operation, one patient had junctional rhythm after the operation that restored to sinus rhythm and 4 patients had persistent atrial fibrillation. During the 12-month follow up, atrial fibrillation was corrected in 82.14%. Doppler echocardiography in these patients with sinus rhythm demonstrated good atrial contractility. This procedure on both atria is effective and less invasive than the original maze procedure to eliminate the atrial fibrillation, and can be performed in patients with valvular heart disease without increasing the risk of operation.

New Procedure for Treatment of Atrial Fibrillation in Patients with Valvular Heart Disease

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Naser Safaie

2010-09-01

Full Text Available "nPatients with valvular heart disease suffer from atrial fibrillation for more than 12 months after valve surgery and have a low probability of remaining in sinus rhythm. We performed an intra-operative procedure similar to surgical maze ІІІ procedure for conversion of this arrhythmia to sinus rhythm. We did this study to evaluate the efficacy of this procedure to restore the sinus rhythm in patients with valvular heart disease. 28 patients with valvular heart disease and chronic persistent atrial fibrillation underwent different combinations of valve surgery and concomitant reduction of left and right atrial size and resection of both atrial auricles in Shahid Madani cardiothoracic center from September 2004 to October 2008. The procedure for atrial fibrillation treatment was performed with cardiopulmonary bypass and after mitral valve replacement. There was one in-hospital death postoperatively because of respiratory failure, but no other complication till 6 months after the operation. Out of 28 patients, 23 were in sinus rhythm one week after the operation, one patient had junctional rhythm after the operation that restored to sinus rhythm and 4 patients had persistent atrial fibrillation. During the 12-month follow up, atrial fibrillation was corrected in 82.14%. Doppler echocardiography in these patients with sinus rhythm demonstrated good atrial contractility. This procedure on both atria is effective and less invasive than the original maze procedure to eliminate the atrial fibrillation, and can be performed in patients with valvular heart disease without increasing the risk of operation.

Embolic risk in atrial fibrillation that arises from hyperthyroidism: review of the medical literature.

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Traube, Elie; Coplan, Neil L

2011-01-01

Atrial fibrillation, the most common cardiac complication of hyperthyroidism, occurs in an estimated 10% to 25% of overtly hyperthyroid patients. The prevalence of atrial fibrillation increases with age in the general population and in thyrotoxic patients. Other risk factors for atrial fibrillation in thyrotoxic patients include male sex, ischemic or valvular heart disease, and congestive heart failure. The incidence of arterial embolism or stroke in thyrotoxic atrial fibrillation is less clear. There are many reports of arterial thromboembolism associated with hyperthyroidism, including cases of young adults without coexisting risk factors other than thyrotoxic atrial fibrillation. The use of anticoagulative agents to prevent thromboembolic sequelae of thyrotoxic atrial fibrillation is controversial: National organizations provide conflicting recommendations in their practice guidelines. Herein, we review the medical literature and examine the evidence behind the recommendations in order to determine the best approach to thromboembolic prophylaxis in patients who have atrial fibrillation that is associated with hyperthyroidism.

Atrial Fibrillation in Embolic Stroke: Anticoagulant Therapy at UNTH ...

African Journals Online (AJOL)

Objective: The decision to commence anticoagulation in a patient with embolic stroke and atrial fibrillation (AF) is often a difficult one for many clinicians. The result can have significant impact on the patient. This study was therefore undertaken to review the use of anticoagulation in embolic stroke in the setting of atrial ...

Impact of congestive heart failure and left ventricular systolic function on the prognostic significance of atrial fibrillation and atrial flutter following acute myocardial infarction

DEFF Research Database (Denmark)

Pedersen, Ole Dyg; Bagger, Henning; Køber, Lars

2005-01-01

fibrillation in acute myocardial infarction patients that might explain previous discrepancies. METHODS: The study population was 6676 patients consecutively admitted to hospital with acute myocardial infarction. Information on the presence of atrial fibrillation/flutter, left ventricular systolic function......BACKGROUND: Reports on the prognostic importance of atrial fibrillation following myocardial infarction have provided considerable variation in results. Thus, this study examined the impact of left ventricular systolic function and congestive heart failure on the prognostic importance of atrial...... and congestive heart failure were prospectively collected. Mortality was followed for 5 years. RESULTS: In patients with left ventricular ejection fraction

Role of the P-wave high frequency energy and duration as noninvasive cardiovascular predictors of paroxysmal atrial fibrillation.

Science.gov (United States)

Alcaraz, Raúl; Martínez, Arturo; Rieta, José J

2015-04-01

A normal cardiac activation starts in the sinoatrial node and then spreads throughout the atrial myocardium, thus defining the P-wave of the electrocardiogram. However, when the onset of paroxysmal atrial fibrillation (PAF) approximates, a highly disturbed electrical activity occurs within the atria, thus provoking fragmented and eventually longer P-waves. Although this altered atrial conduction has been successfully quantified just before PAF onset from the signal-averaged P-wave spectral analysis, its evolution during the hours preceding the arrhythmia has not been assessed yet. This work focuses on quantifying the P-wave spectral content variability over the 2h preceding PAF onset with the aim of anticipating as much as possible the arrhythmic episode envision. For that purpose, the time course of several metrics estimating absolute energy and ratios of high- to low-frequency power in different bands between 20 and 200Hz has been computed from the P-wave autoregressive spectral estimation. All the analyzed metrics showed an increasing variability trend as PAF onset approximated, providing the P-wave high-frequency energy (between 80 and 150Hz) a diagnostic accuracy around 80% to discern between healthy subjects, patients far from PAF and patients less than 1h close to a PAF episode. This discriminant power was similar to that provided by the most classical time-domain approach, i.e., the P-wave duration. Furthermore, the linear combination of both metrics improved the diagnostic accuracy up to 88.07%, thus constituting a reliable noninvasive harbinger of PAF onset with a reasonable anticipation. The information provided by this methodology could be very useful in clinical practice either to optimize the antiarrhythmic treatment in patients at high-risk of PAF onset and to limit drug administration in low risk patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Does Myocardial Infarction Beget Atrial Fibrillation and Atrial Fibrillation Beget Myocardial Infarction?

NARCIS (Netherlands)

Vermond, Rob A.; Van Gelder, Isabelle C.; Crijns, Harry J.; Rienstra, Michiel

2015-01-01

Atrial fibrillation (AF) affects millions of people worldwide.(1) It is already known several decades that AF is not a benign condition, and it's associated with a 5-fold increased risk of stroke, 3-fold increased risk of heart failure, and doubling of risk of dementia and death.(2-4) Myocardial

Management of left atrial myxomas at civil hospital, Karachi

International Nuclear Information System (INIS)

Iqbal, M.I.; Khan, A.B.; Aftab, S.; Mahmood, S.A.

2008-01-01

To study the outcome of the management of left atrial myxoma. The diagnosis was made according to clinical presentation and echocardiographic examinations. Tumour excised under cardiopulmonary bypass using aortic and bicaval cannulation and moderate hypothermia. Variables noted were surgical approach, pathological findings and complications after surgery. Of the 12 cases, six were male and six female, with a mean age of 33.67+-6.05 years. Fatigue and fever were the most common general symptoms, and dyspnoea the most common cardiologic symptom. The pedunculated atrial tumours were excised by trans-septal approach; tumour size ranged between 1.5x1x0.7 cms to 9x8x6 cms and weight 3-140 gms. Histopathology confirmed the tumours as atrial myxomas. One patient died of cerebrovascular accident on the 3rd postoperative day. So far, there has been no recurrence of the tumours. Surgical treatment with wide excision of left atrial myxomas by trans-septal approach is a suitable approach with negligible chances of recurrence. (author)

Atrial myxoma-related embolism resulting in acute limb ischaemia in ...

African Journals Online (AJOL)

Although atrial myxomas are uncommon, a thorough investigation of patients presenting with acute peripheral ischaemic .... reported.[9] Large left atrial tumours impairing intracardiac blood flow can ... In the case described here, obstruction of the mitral valve by the myxoma ... operation, preventing histological confirmation.

Atrial fibrillation and bleeding complication - risk factors and risk marker

NARCIS (Netherlands)

Breithardt, G.; Ravens, U.; Kirchhof, P.; van Gelder, I. C.

2012-01-01

The development of atrial fibrillation (AF) is closely linked to risk factors like hypertension and heart failure, diabetes mellitus, myocardial infarction and valvular heart disease. These factors partly overlap with those which determine the progression of atrial fibrillation and the incidence of

Long working hours as a risk factor for atrial fibrillation

DEFF Research Database (Denmark)

Kivimäki, Mika; Nyberg, Solja T.; Batty, G. David

2017-01-01

long hours (≤55 per week) and those working standard 35-40 h/week. Methods and results In this prospective multi-cohort study from the Individual-Participant-Data Meta-Analysis in Working Populations (IPD-Work) Consortium, the study population was 85 494 working men and women (mean age 43.4 years...... of atrial fibrillation (10-year cumulative incidence 12.4 per 1000). After adjustment for age, sex and socioeconomic status, individuals working long hours had a 1.4-fold increased risk of atrial fibrillation compared with those working standard hours (hazard ratio = 1.42, 95% CI= 1.13-1.80, P= 0......Aims Studies suggest that people who work long hours are at increased risk of stroke, but the association of long working hours with atrial fibrillation, the most common cardiac arrhythmia and a risk factor for stroke, is unknown. We examined the risk of atrial fibrillation in individuals working...

Cryoballoon Catheter Ablation in Atrial Fibrillation

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Cevher Ozcan

2011-01-01

Full Text Available Pulmonary vein isolation with catheter ablation is an effective treatment in patients with symptomatic atrial fibrillation refractory or intolerant to antiarrhythmic medications. The cryoballoon catheter was recently approved for this procedure. In this paper, the basics of cryothermal energy ablation are reviewed including its ability of creating homogenous lesion formation, minimal destruction to surrounding vasculature, preserved tissue integrity, and lower risk of thrombus formation. Also summarized here are the publications describing the clinical experience with the cryoballoon catheter ablation in both paroxysmal and persistent atrial fibrillation, its safety and efficacy, and discussions on the technical aspect of the cryoballoon ablation procedure.

Origin and pharmacological response of atrial tachyarrhythmias induced by activation of mediastinal nerves in canines.

Science.gov (United States)

Armour, J Andrew; Richer, Louis-Philippe; Pagé, Pierre; Vinet, Alain; Kus, Teresa; Vermeulen, Michel; Nadeau, Réginald; Cardinal, René

2005-03-31

We sought to determine the sites of origin of atrial tachyarrhythmias induced by activating mediastinal nerves, as well as the response of such arrhythmias to autonomic modulation. Under general anaesthesia, atrioventricular block was induced after thoracotomy in 19 canines. Brief trains of 5 electrical stimuli were delivered to right-sided mediastinal nerves during the atrial refractory period. Unipolar electrograms were recorded from 191 right and left atrial epicardial sites under several conditions, i.e. (i) with intact nervous systems and following (ii) acute decentralization of the intrathoracic nervous system or administration of (iii) atropine, (iv) timolol, (v) hexamethonium. Concomitant right atrial endocardial mapping was performed in 7 of these dogs. Mediastinal nerve stimulation consistently initiated bradycardia followed by atrial tachyarrhythmias. In the initial tachyarrhythmia beats, early epicardial breakthroughs were identified in the right atrial free wall (28/50 episodes) or Bachmann bundle region (22/50), which corresponded to endocardial sites of origin associated with the right atrial subsidiary pacemaker complex, i.e. the crista terminalis and dorsal locations including the right atrial aspect of the interatrial septum. Neuronally induced responses were eliminated by atropine, modified by timolol and unaffected by acute neuronal decentralization. After hexamethonium, responses to extra-pericardial but not intra-pericardial nerve stimulation were eliminated. It is concluded that concomitant activation of cholinergic and adrenergic efferent intrinsic cardiac neurons induced by right-sided efferent neuronal stimulation initiates atrial tachyarrhythmias that originate from foci anatomically related to the right atrial pacemaker complex and tissues underlying major atrial ganglionated plexuses.

Focal ablation for atrial tachycardia from the double-exit of the Marshall bundle inducing atrial fibrillation

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Jung Yeon Chin, MD

2017-08-01

Full Text Available Atrial fibrillation (AF from the ligament/vein of Marshall (LOM/VOM has previously been described. We report the case of a 23-year-old woman with an antiarrhythmic drug-resistant AF induced by two distinct atrial tachycardias (ATs. Focal ablation of these ATs from the double-exit of the Marshall bundle using a three-dimensional map eliminated AF triggering, even though pulmonary vein electrical isolation is the cornerstone for paroxysmal AF. Such mechanisms are important as triggering factors to plan ablation for paroxysmal AF. Focal ablation for triggering and inducing AF, originating from the double-exit of the Marshall bundle may be effective in eliminating AF in young patients.

Modulation of atrial fibrillation

NARCIS (Netherlands)

Geuzebroek, G.S.C.

2013-01-01

In this thesis we investigate the results of various surgical procedures for atrial fibrillation which have been performed in the last 2 decades in the Sint Antonius Hospital, Nieuwegein, The Netherlands. In the 1990s the classical Maze III procedure was the main surgical technique for

The imaging features of neurologic complications of left atrial myxomas

Energy Technology Data Exchange (ETDEWEB)

Liao, Wei-Hua; Ramkalawan, Divya; Liu, Jian-Ling; Shi, Wei [Department of Radiology, Xiangya Hospital, Central South University, Changsha 410008, Hunan (China); Zee, Chi-Shing [Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033 (United States); Yang, Xiao-Su; Li, Guo-Liang; Li, Jing [Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan (China); Wang, Xiao-Yi, E-mail: cjr.wangxiaoyi@vip.163.com [Department of Radiology, Xiangya Hospital, Central South University, Changsha 410008, Hunan (China)

2015-05-15

Background: Neurologic complications may be the first symptoms of atrial myxomas. Understanding the imaging features of neurologic complications of atrial myxomas can be helpful for the prompt diagnosis. Objective: To identify neuroimaging features for patients with neurologic complications attributed to atrial myxoma. Methods: We retrospectively reviewed the medical records of 103 patients with pathologically confirmed atrial myxoma at Xiangya Hospital from January 2009 to January 2014. The neuroimaging data for patients with neurologic complications were analyzed. Results: Eight patients with atrial myxomas (7.77%) presented with neurologic manifestations, which constituted the initial symptoms for seven patients (87.5%). Neuroimaging showed five cases of cerebral infarctions and three cases of aneurysms. The main patterns of the infarctions were multiplicity (100.0%) and involvement of the middle cerebral artery territory (80.0%). The aneurysms were fusiform in shape, multiple in number (100.0%) and located in the distal middle cerebral artery (100.0%). More specifically, high-density in the vicinity of the aneurysms was observed on CT for two patients (66.7%), and homogenous enhancement surrounding the aneurysms was detected in the enhanced imaging for two patients (66.7%). Conclusion: Neurologic complications secondary to atrial myxoma consist of cerebral infarctions and aneurysms, which show certain characteristic features in neuroimaging. Echocardiography should be performed in patients with multiple cerebral infarctions, and multiple aneurysms, especially when aneurysms are distal in location. More importantly, greater attention should be paid to the imaging changes surrounding the aneurysms when myxomatous aneurysms are suspected and these are going to be the relevant features in our article.

The imaging features of neurologic complications of left atrial myxomas

International Nuclear Information System (INIS)

Liao, Wei-Hua; Ramkalawan, Divya; Liu, Jian-Ling; Shi, Wei; Zee, Chi-Shing; Yang, Xiao-Su; Li, Guo-Liang; Li, Jing; Wang, Xiao-Yi

2015-01-01

Background: Neurologic complications may be the first symptoms of atrial myxomas. Understanding the imaging features of neurologic complications of atrial myxomas can be helpful for the prompt diagnosis. Objective: To identify neuroimaging features for patients with neurologic complications attributed to atrial myxoma. Methods: We retrospectively reviewed the medical records of 103 patients with pathologically confirmed atrial myxoma at Xiangya Hospital from January 2009 to January 2014. The neuroimaging data for patients with neurologic complications were analyzed. Results: Eight patients with atrial myxomas (7.77%) presented with neurologic manifestations, which constituted the initial symptoms for seven patients (87.5%). Neuroimaging showed five cases of cerebral infarctions and three cases of aneurysms. The main patterns of the infarctions were multiplicity (100.0%) and involvement of the middle cerebral artery territory (80.0%). The aneurysms were fusiform in shape, multiple in number (100.0%) and located in the distal middle cerebral artery (100.0%). More specifically, high-density in the vicinity of the aneurysms was observed on CT for two patients (66.7%), and homogenous enhancement surrounding the aneurysms was detected in the enhanced imaging for two patients (66.7%). Conclusion: Neurologic complications secondary to atrial myxoma consist of cerebral infarctions and aneurysms, which show certain characteristic features in neuroimaging. Echocardiography should be performed in patients with multiple cerebral infarctions, and multiple aneurysms, especially when aneurysms are distal in location. More importantly, greater attention should be paid to the imaging changes surrounding the aneurysms when myxomatous aneurysms are suspected and these are going to be the relevant features in our article

Dynamic cycling in atrial size and flow during obstructive apnoea.

Science.gov (United States)

Pressman, Gregg S; Cepeda-Valery, Beatriz; Codolosa, Nicolas; Orban, Marek; Samuel, Solomon P; Somers, Virend K

2016-01-01

Obstructive sleep apnoea (OSA) is strongly associated with cardiovascular disease. However, acute cardiovascular effects of repetitive airway obstruction are poorly understood. While past research used a sustained Mueller manoeuver to simulate OSA we employed a series of gasping efforts to better simulate true obstructive apnoeas. This report describes acute changes in cardiac anatomy and flow related to sudden changes in intrathoracic pressure. 26 healthy, normal weight participants performed 5-6 gasping efforts (target intrathoracic pressure -40 mm Hg) while undergoing Doppler echocardiography. 14 participants had sufficient echocardiographic images to allow comparison of atrial areas during the manoeuver with baseline measurements. Mitral and tricuspid E-wave and A-wave velocities postmanoeuver were compared with baseline in all participants. Average atrial areas changed little during the manoeuver, but variance in both atrial areas was significantly greater than baseline. Further, an inverse relationship was noted with left atrial collapse and right atrial enlargement at onset of inspiratory effort. Significant inverse changes were noted in Doppler flow when comparing the first beat postmanoeuver (pMM1) with baseline. Mitral E-wave velocity increased 9.1 cm/s while tricuspid E-wave velocity decreased 7.0 cm/s; by the eighth beat postmanoeuver (pMM8) values were not different from baseline. Mitral and tricuspid A-wave velocities were not different from baseline at pMM1, but both were significantly higher by pMM8. Repetitive obstructive apnoeas produce dynamic, inverse changes in atrial size and Doppler flow across the atrioventricular valves. These observations have important implications for understanding the pathophysiology of OSA.

Limitations of Dower's inverse transform for the study of atrial loops during atrial fibrillation.

Science.gov (United States)

Guillem, María S; Climent, Andreu M; Bollmann, Andreas; Husser, Daniela; Millet, José; Castells, Francisco

2009-08-01

Spatial characteristics of atrial fibrillatory waves have been extracted by using a vectorcardiogram (VCG) during atrial fibrillation (AF). However, the VCG is usually not recorded in clinical practice and atrial loops are derived from the 12-lead electrocardiogram (ECG). We evaluated the suitability of the reconstruction of orthogonal leads from the 12-lead ECG for fibrillatory waves in AF. We used the Physikalisch-Technische Bundesanstalt diagnostic ECG database, which contains 15 simultaneously recorded signals (12-lead ECG and three Frank orthogonal leads) of 13 patients during AF. Frank leads were derived from the 12-lead ECG by using Dower's inverse transform. Derived leads were then compared to true Frank leads in terms of the relative error achieved. We calculated the orientation of AF loops of both recorded orthogonal leads and derived leads and measured the difference in estimated orientation. Also, we investigated the relationship of errors in derivation with fibrillatory wave amplitude, frequency, wave residuum, and fit to a plane of the AF loops. Errors in derivation of AF loops were 68 +/- 31% and errors in the estimation of orientation were 35.85 +/- 20.43 degrees . We did not find any correlation among these errors and amplitude, frequency, or other parameters. In conclusion, Dower's inverse transform should not be used for the derivation of orthogonal leads from the 12-lead ECG for the analysis of fibrillatory wave loops in AF. Spatial parameters obtained after this derivation may differ from those obtained from recorded orthogonal leads.

Excessive Premature Atrial Complexes and the Risk of Recurrent Stroke or Death in an Ischemic Stroke Population.

Science.gov (United States)

Vinther, Kristina H; Tveskov, Claus; Möller, Sören; Auscher, Soren; Osmanagic, Armin; Egstrup, Kenneth

2017-06-01

Our aim was to investigate the association of premature atrial complexes and the risk of recurrent stroke or death in patients with ischemic stroke in sinus rhythm. In a prospective cohort study, we used 24-hour Holter recordings to evaluate premature atrial complexes in patients consecutively admitted with ischemic strokes. Excessive premature atrial complexes were defined as >14 premature atrial complexes per hour and 3 or more runs of premature atrial complexes per 24 hours. During follow-up, 48-hour Holter recordings were performed after 6 and 12 months. Among patients in sinus rhythm, the association of excessive premature atrial complexes and the primary end point of recurrent stroke or death were estimated in both crude and adjusted Cox proportional hazards models. We further evaluated excessive premature atrial complexes contra atrial fibrillation in relation to the primary end point. Of the 256 patients included, 89 had atrial fibrillation. Of the patients in sinus rhythm (n = 167), 31 had excessive premature atrial complexes. During a median follow-up of 32 months, 50 patients (30% of patients in sinus rhythm) had recurrent strokes (n = 20) or died (n = 30). In both crude and adjusted models, excessive premature atrial complexes were associated with the primary end point, but not with newly diagnosed atrial fibrillation. Compared with patients in atrial fibrillation, those with excessive premature atrial complexes had similarly high risks of the primary end point. In patients with ischemic stroke and sinus rhythm, excessive premature atrial complexes were associated with a higher risk of recurrent stroke or death. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Anatomy of a wrong diagnosis: false Sinus Venosus Atrial Septal Defect

Directory of Open Access Journals (Sweden)

Montresor Graziano

2003-11-01

Full Text Available Abstract In contrast with transthoracic echocardiography, transesophageal echocardiography provides a sure way to make the diagnosis of sinus venosus atrial septal defect; on the other hand this abnormality is more complex than that seen with the secundum atrial septal defect, and inexperienced operators may fail to recognize properly the defect. In front of a high reported sensitivity using transesophageal echocardiography, specificity is difficult to assess, due to possible underreporting of diagnostic errors. We describe a false positive diagnosis of sinus venosus atrial septal defect, in the setting of enlarged right chambers of the heart because of pressure overload. Modified anatomy of the heart, together with the presence of a prominent linear structure(probably Eustachian Valve and an incomplete examination in this case made image interpretation very prone to misinterpretation. In this anatomical setting transesophageal longitudinal "bicaval" view may be sub-optimal for examining the atrial septum, potentially showing false images that need to be known for correct image interpretation. Nonetheless, a scan plane taken more accurately at the superior level would have demonstrated/excluded the pathognomonic feature of sinus venosus atrial septal defect in the high atrial septum, between the fatty limbus and the inferior aspect of the right pulmonary artery; moreover TEE allows morphological information about the posterior structures of the heart that need to be investigated in detail for a complete diagnosis.

Atrial Septal Aneurysm Presenting as Clubbing without Clinically Apparent Cyanosis.

Science.gov (United States)

Goyal, Laxmi Kant; Banerjee, S; Yadav, R N; Singh, Gajraj; Ganguli, Sujata; Isran, Rohit

2015-09-01

Atrial septal aneurysm (ASA) is a localised "saccular" deformity which protrudes to the right or the left atrium or on both sides. It is a rare, but well recognised cardiac abnormality. It is usually an incidental finding or may presents as atrial arrhythmias or arterial embolism. Though it is an acyanotic congenital heart disease but it may result in significant right to left shunt and cyanosis. We describe a patient of ASA with atrial septal defect who presented with clubbing and right to left shunt without clinically apparent cyanosis. © Journal of the Association of Physicians of India 2011.

Pattern of Colon Cancer Lymph Node Metastases in Patients Undergoing Central Mesocolic Lymph Node Excision

DEFF Research Database (Denmark)

Bertelsen, Claus A; Kirkegaard-Klitbo, Anders; Nielsen, Mingyuan

2016-01-01

BACKGROUND: Extended mesocolic lymph node dissection in colon cancer surgery seems to improve oncological outcome. A possible reason might be related to metastases in the central mesocolic lymph nodes. OBJECTIVE: The purpose of this study was to describe the pattern of mesocolic lymph node...... metastases, particularly in central lymph nodes, and the risk of skip, aberrant, and gastrocolic ligament metastases as the argument for performing extended lymph node dissection. DATA SOURCES: EMBASE and PubMed were searched using the terms colon or colorectal with sentinel node, lymph node mapping, or skip...... node; lymph node resection colon; and complete or total and mesocolic excision. STUDY SELECTION: Studies describing the risk of metastases in central, skip, aberrant, and gastrocolic ligament lymph node metastases from colon adenocarcinomas in 10 or more patients were included. No languages were...

[Panic disorder and atrial fibrillation].

Science.gov (United States)

Olazabal Eizaguirre, N; Chavez, R; González-Torres, M A; Gaviria, M

2013-10-01

This paper studies the relationship between atrial fibrillation and panic disorder. There are often doubts on the differential diagnosis in emergency services and general medical settings. Panic disorder prevalence rates have been found to be high in patients suffering from atrial fibrillation. Various studies have observed that patients diagnosed with anxiety disorders frequently have higher cardiovascular disease rates compared to the general population. Usually, patients suffering from panic disorder exhibit somatic complaints suggesting coronary disease, such as chest pain or palpitations. The aim is to make the correct diagnosis and treatment for these different illnesses, and to decrease the costs due to misdiagnosis. Copyright © 2012 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

Self-discharge analysis and characterization of supercapacitors for environmentally powered wireless sensor network applications

Science.gov (United States)

Yang, Hengzhao; Zhang, Ying

2011-10-01

A new approach is presented to characterize the variable leakage resistance, a parameter in the variable leakage resistance model we developed to model supercapacitors used in environmentally powered wireless sensor network applications. Based on an analysis of the supercapacitor terminal behavior during the self-discharge, the variable leakage resistance is modeled as a function of the supercapacitor terminal voltage instead of the self-discharge time, which is more practical for an environmentally powered wireless sensor node. The new characterization approach is implemented and validated using MATLAB Simulink with a 10 F supercapacitor as an example. In addition, effects of initial voltages and temperatures on the supercapacitor self-discharge rate and the variable leakage resistance value are explored.

Patients with atrial fibrillation and permanent pacemaker

DEFF Research Database (Denmark)

Dalgaard, Frederik; Ruwald, Martin H; Lindhardt, Tommi Bo

2018-01-01

BACKGROUND: The management of patients with non-valvular atrial fibrillation (NVAF) with rate-lowering or anti-arrhythmic drugs has markedly changed over the last decade, but it is unknown how these changes have affected patients with NVAF with a permanent pacemaker (PPM). METHODS: Through Danish......,261. Thus, the proportional amount of NVAF patients with a PPM decreased from 1.3% to 1.1% (p = 0.015). Overall 45.9% had atrial fibrillation (AF) duration less than one year and the proportion declined from 55.5% to 42.4% (p

Integrating new approaches to atrial fibrillation management

DEFF Research Database (Denmark)

Kotecha, Dipak; Breithardt, Günter; Camm, A John

2018-01-01

There are major challenges ahead for clinicians treating patients with atrial fibrillation (AF). The population with AF is expected to expand considerably and yet, apart from anticoagulation, therapies used in AF have not been shown to consistently impact on mortality or reduce adverse...... of the Atrial Fibrillation Network (AFNET) and the European Heart Rhythm Association (EHRA), held at the European Society of Cardiology Heart House in Sophia Antipolis, France, 17-19 January 2017. Sixty-two global specialists in AF and 13 industry partners met to develop innovative solutions based on new...

Partial axillary lymph node dissection inferior to the intercostobrachial nerves complements sentinel node biopsy in patients with clinically node-negative breast cancer.

Science.gov (United States)

Li, Jianyi; Jia, Shi; Zhang, Wenhai; Qiu, Fang; Zhang, Yang; Gu, Xi; Xue, Jinqi

2015-06-30

The practice of breast cancer diagnosis and treatment in China varies to that in western developed countries. With the unavailability of radioactive tracer technique for sentinel lymph nodes biopsy (SLNB), using blue dye alone has been the only option in China. Also, the diagnosis of breast malignant tumor in most Chinese centres heavily relies on intraoperative instant frozen histology which is normally followed by sentinel lymph nodes mapping, SLNB and the potential breast and axillary operations in one consecutive session. This practice appears to cause a high false negative rate (FNR) for SLNB. The present study aimed to investigate the impact of the current practice in China on the accuracy of SLNB, and whether partial axillary lymph node dissection (PALND), dissection of lymph nodes inferior to the intercostobrachial nerve (ICBN), was a good complementary procedure following SLNB using blue dye. 289 patients with clinically node-negative breast cancer were identified and recruited. Tumorectomy, intraoperative instant frozen histological diagnosis, SLNB using methylene blue dye, and PALND or complete axillary node dissection (ALND) were performed in one consecutive operative session. The choice of SLNB only, SLNB followed by PALND or by ALND was based on the pre-determined protocol and preoperative choice by the patient. Clinical parameters were analyzed and survival analysis was performed. 37% patients with clinically negative nodes were found nodes positive. 59 patients with positive SLN underwent ALND, including 47 patients with up to two positive nodes which were all located inferior to the ICBN. 9 patients had failed SLNB and underwent PALND. Among them, 3 (33.3%) patients were found to have one metastatic node. 149 patients showed negative SLNB but chose PALND. Among them, 30 (20.1%), 14 (9.4) and 1 (0.7%) patients were found to have one, two and three metastatic node(s), respectively. PALND detected 48 (30.4%) patients who had either failed SLNB or

Impact of ischemic and valvular heart disease on atrial excitation : A high-resolution epicardial mapping study

NARCIS (Netherlands)

E.M.J.P. Mouws (Elisabeth); E. Lanters (Eva); C. Teuwen (Christophe); L. van der Does (Lisette); C. Kik (Charles); S.P. Knops (Simon); A. Yaksh (Ameeta); J.A. Bekkers (Jos); A.J.J.C. Bogers (Ad); N.M.S. de Groot (Natasja)

2018-01-01

markdownabstractBackground--The influence of underlying heart disease or presence of atrial fibrillation (AF) on atrial excitation during sinus rhythm (SR) is unknown. We investigated atrial activation patterns and total activation times of the entire atrial epicardial surface during SR in patients

Atrial and ventricular septal defect with pulmonary and tricuspid valvular anomalies in a dog

International Nuclear Information System (INIS)

Ishikawa, Y.; Wakao, Y.; Watanabe, T.; Minami, T.; Muto, M.; Suzuki, T.; Takahashi, M.; Une, Y.; Nomura, Y.; Ichioka, N.

1989-01-01

A 15-month-old male boxer dog weighing 22 kg was referred to Azabu University Animal Hospital for evaluation of the syncopal attack. There was no cardiac murmur, but electrocardiograms revealed an atrial fibrillation. Thoracic radiograph revealed enlargement of the right and left atrial regions. The medical treatment with digitalis and captopril was made for conversion from the atrial fibrillation to the sinus rhythm. By cardiac catheterization, atrial and ventricular septal defect with pulmonary stenosis was demonstrated. The patient died at 20 months from the first medical examination. At autopsy, there were severe enlargement of both atria, atrial defect, and pulmonary and tricuspid valvular anomalies. (author)

Atrial and ventricular septal defect with pulmonary and tricuspid valvular anomalies in a dog

Energy Technology Data Exchange (ETDEWEB)

Ishikawa, Y. [Azabu Univ., Sagamihara, Kanagawa (Japan); Wakao, Y.; Watanabe, T.; Minami, T.; Muto, M.; Suzuki, T.; Takahashi, M.; Une, Y.; Nomura, Y.; Ichioka, N.

1989-12-15

A 15-month-old male boxer dog weighing 22 kg was referred to Azabu University Animal Hospital for evaluation of the syncopal attack. There was no cardiac murmur, but electrocardiograms revealed an atrial fibrillation. Thoracic radiograph revealed enlargement of the right and left atrial regions. The medical treatment with digitalis and captopril was made for conversion from the atrial fibrillation to the sinus rhythm. By cardiac catheterization, atrial and ventricular septal defect with pulmonary stenosis was demonstrated. The patient died at 20 months from the first medical examination. At autopsy, there were severe enlargement of both atria, atrial defect, and pulmonary and tricuspid valvular anomalies. (author)

Retrospective analysis of mode survival, reliability of atrial sensing and incidence of atrial tachyarrhythmias in 307 single-lead VDD pacemaker patients.

Science.gov (United States)

Zupan, Igor; Lipar, Luka; Zizek, David; Boute, Wim; Vidmar, Masa; Gabrijelcic, Tone; Rakovec, Peter; Brecelj, Ales

2006-10-01

The aim of this retrospective analysis was to investigate VDD mode survival, development of atrial tachyarrhythmias (AT), and long-term atrial sensing performance of VDD pacing systems. We implanted single-lead VDD pacemakers in patients with isolated atrioventricular block and performed a retrospective analysis of 307 patients who had their devices implanted between May 1994 and September 2001. In 39 patients (12.7%), the pacing mode had to be reprogrammed to a single-chamber ventricular pacing mode, mostly due to permanent AT. In 16 of these patients, the atrial sensing safety margin was less than 150%. The atrial sensing safety margin was insufficient, i.e. less than 100% in only seven patients. Although only 12 (3.9%) of the patients had a history of paroxysmal AT at the time of pacemaker implantation, 200 (65%) patients presented with AT during follow-up. The mean AT burden at the last follow-up was 2.5%. These data illustrate that single-lead VDD pacemakers can be applied without serious complications in a highly selected group of patients. Our main concern is the development of AT in a large part of our population. Over a 10-year period, two thirds of our patients presented with AT.

Percutaneous closure of the left atrial appendage in patients with diabetes mellitus.

Science.gov (United States)

Azizy, Obayda; Rammos, Christos; Lehmann, Nils; Rassaf, Tienush; Kälsch, Hagen

2017-09-01

Left atrial appendage closure is a preventive treatment of atrial fibrillation-related thrombo-embolism. Patients with diabetes mellitus have increased risk for a negative outcome in percutaneous cardiac interventions. We assessed whether percutaneous left atrial appendage closure is safe and effective in patients with diabetes mellitus. We included 78 patients (mean age of 74.4 ± 8.3 years) with indication for left atrial appendage closure in an open-label observational single-centre study. Patients with diabetes mellitus ( n = 31) were at higher thrombo-embolic and bleeding risk (CHA 2 DS 2 -VASc: 4.5 ± 0.9, HAS-BLED: 4.7 ± 0.7) compared to patients without diabetes mellitus ( n = 47, CHA 2 DS 2 -VASc: 3.5 ± 1.0, HAS-BLED: 4.1 ± 0.8; p diabetes mellitus (Euro II-Score: 6.6 ± 3.7 vs 3.9 ± 1.9, p diabetes mellitus had no events ( p = 0.672). Follow-up of 6 months revealed no bleeding complication in both groups. No stroke occurred in follow-up, and left atrial appendage flow velocity reduction (55.6 ± 38.6 vs 51.4 ± 19.1 cm/s, p = 0.474) and rate of postinterventional leakage in the left atrial appendage were comparable (0% vs 2.1%, p = 0.672). Despite patients with diabetes mellitus are high-risk patients, the outcome of percutaneous left atrial appendage closure is similar to patients without diabetes mellitus.

Implementing hospital guidelines improves warfarin use in non-valvular atrial fibrillation: a before-after study

Directory of Open Access Journals (Sweden)

Piobbici Marina

2007-08-01

Full Text Available Abstract Background The use of oral anticoagulant therapy (OAT to prevent non-valvular atrial fibrillation (NVAF related-strokes is often sub-optimal. We aimed to evaluate whether implementing guidelines on antithrombotic therapy (AT by a multifaceted strategy may improve appropriateness of its prescription in NVAF-patients discharged from a large tertiary-care hospital. Methods A survey was conducted on all consecutive NVAF patients discharged before (1st January–30th June 2000, n = 313 and after (1st January–30th June 2004, n = 388 guideline development and implementation. Results When strongly recommended, OAT use increased from 56.6% (60/106 in 2000 to 81.9% (86/105 in 2004, with an absolute difference of +25.3% (95%CI: 15% 35%. In patients for whom the choice OAT/acetylsalicylic acid should be individualised, those discharged without any AT were 33.7% (34/101 in 2000 and 16.9% (21/124 in 2004 (-16.7%;95%CI: -26.2% -7.2%. In a logistic regression model, OAT prescription in 2004 was increased by 2.11 times (95%CI: 1.47 3.04, after accounting for stroke risk, presence of contraindications (OR = 0.18; 0.13 0.27, older age (OR = 0.30; 0.21 0.45, prophylaxis at admission (OR = 3.03; 2.08 4.43. OAT was positively associated with the stroke risk in the 2004 sample only. Conclusion The guideline implementation has substantially improved the appropriateness of OAT at discharge, through a better evaluation at patient's individual level of the benefit-to-risk ratio.

Identification and purification of human induced pluripotent stem cell-derived atrial-like cardiomyocytes based on sarcolipin expression.

Directory of Open Access Journals (Sweden)

Rebecca Josowitz

Full Text Available The use of human stem cell-derived cardiomyocytes to study atrial biology and disease has been restricted by the lack of a reliable method for stem cell-derived atrial cell labeling and purification. The goal of this study was to generate an atrial-specific reporter construct to identify and purify human stem cell-derived atrial-like cardiomyocytes. We have created a bacterial artificial chromosome (BAC reporter construct in which fluorescence is driven by expression of the atrial-specific gene sarcolipin (SLN. When purified using flow cytometry, cells with high fluorescence specifically express atrial genes and display functional calcium handling and electrophysiological properties consistent with atrial cardiomyocytes. Our data indicate that SLN can be used as a marker to successfully monitor and isolate hiPSC-derived atrial-like cardiomyocytes. These purified cells may find many applications, including in the study of atrial-specific pathologies and chamber-specific lineage development.

Clinical characteristics, management, and control of permanent vs. nonpermanent atrial fibrillation: insights from the RealiseAF survey.

LENUS (Irish Health Repository)

Murin, Jan

2014-01-01

Atrial fibrillation can be categorized into nonpermanent and permanent atrial fibrillation. There is less information on permanent than on nonpermanent atrial fibrillation patients. This analysis aimed to describe the characteristics and current management, including the proportion of patients with successful atrial fibrillation control, of these atrial fibrillation subsets in a large, geographically diverse contemporary sample.

Increased base rate of atrial pacing for prevention of atrial fibrillation after implantation of a dual-chamber pacemaker: insights from the Atrial Overdrive Pacing Study.

Science.gov (United States)

Kantharia, Bharat K; Freedman, Roger A; Hoekenga, David; Tomassoni, Gery; Worley, Seth; Sorrentino, Robert; Steinhaus, David; Wolkowicz, Joel M; Syed, Zaffer A

2007-11-01

Different pacing sites and various algorithms have been utilized to prevent atrial fibrillation (AF) in pacemaker recipients. However, the optimal pacing rate settings have not yet been established. In this randomized, prospective, multicentre, single-blinded, cross over study, rate-adaptive pacing at a high base rate (BR) in patients, age 60 years or above, or a history of paroxysmal AF, who underwent dual-chamber (DDD) pacemaker implantation for standard pacing indications, was evaluated for prevention of AF. In the study cohort of 145 patients implanted with DDD pacemakers with a programmable rest rate (RR) feature, the BR/RR settings were sequentially but randomly adjusted as follows: 60 bpm/Off for the baseline quarter (initial 3 months) and then to either 'A-B-C' or 'C-B-A' settings (A = 70/65 bpm, B = 70/Off, C = 80/65 bpm) for the subsequent quarters each of 3 months duration. Data on automatic mode switch episodes, device diagnostics, and a questionnaire evaluating pacemaker awareness and palpitations were collected. Ninety-nine patients, mean age 77 +/- 10 years, who completed the study protocol and followed for 12 months did not show significant differences in the number of mode switch episodes between any settings used. The percentage of atrial pacing was lower during baseline pacing compared to settings A, B, and C (P < 0.0001). Setting C produced a higher percentage of atrial pacing than A and B (P < 0.01). Although a higher percentage of atrial pacing correlated with a lower incidence of mode switch episodes, there was no statistically significant difference in the number of mode switch episodes between settings A, B, and C. There were no significant differences in the questionnaire scores relating to pacemaker awareness or palpitation. Overdrive single-site pacing in the right atrium achieved by programming analysed settings in the present study did not reduce AF as assessed by mode switch episodes. Additionally, no change in the symptoms of

[Echocardiographic factors predictive of restoration and maintenance of sinus rhythm after reduction of atrial fibrillation].

Science.gov (United States)

Ben Khalfallah, A; Sanaa, I

2007-09-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia. While the arrhythmia was initially thought to be little more than a nuisance, it is now clear that AF has a significant negative impact on quality of life and a corresponding increase in both morbidity and mortality. The aim of this study was to identify Doppler echographic patterns that allow prediction of atrial fibrillation reduction and maintenance of sinus rhythm within 12 months. One hundred and thirty patients having permanent atrial fibrillation, recent (51) or chronic (79) are included in the study, excepting those with valvular heart disease or thyroid dysfunction. The mean age was 63.5 +/- 11.3 years. Both transthoracic and transoesophageal echocardiography was performed using a Philips SONOS 5500 Echograph, before cardioversion. Were studied: end diastolic and systolic left ventricular diameters, left ventricular ejectionnal fraction, left atrial area (LAA), left atrial diameter, left atrial appendage area and peak emptying velocities of the left atrial appendage (PeV). Sinus rhythm was re-established in 102 patients (44 having recent and 58 chronic atrial fibrillation). Sinus rhythm was maintained for 12 months in 79 patients. Within the echographic parameters studied, the left atrial area (LAA) and peak emptying velocities of left atrial appendage (PeV) before cardioversion were the best predictors of restoration of sinus rhythm. On monovariate analysis, SOG is significantly lower and PicV is significantly higher in patients whose sinus rhythm had been restored in comparison with those with permanent atrial fibrillation. (Mean SOG: 27.7 +/- 7.62 vs. 34 +/- 7,6 cm2, ppredict on mono and multivariate analysis (p=0.05, OR=0.5, IC=0.36 à 3.56), re-establishing of sinus rhythm whereas in patients with chronic atrial fibrillation, peak emptying velocity of left atrial appendage predict better re-establishing of sinus rhythm (p=0.04, OR=1.29, IC=0.12 à 4.23). The threshold values of LAA and Pe

Visualization of atrial myocardium with thallium-201: case report

International Nuclear Information System (INIS)

Cowley, M.J.; Coghlan, H.C.; Logic, J.R.

1977-01-01

An adult patient evaluated for cyanotic congenital heart disease was found to have pulmonary atresia with intact ventricular septum, hypoplastic right ventricle, and right atrial enlargement. Thallium-201 myocardial imaging before surgical correction showed thallium activity in the right atrium. Following the establishment of a conduit from the right atrium to pulmonary artery, the right-atrial thallium uptake was even more prominent

Use of Vitamins K antagonists in non-valvular atrial fibrillation ...

African Journals Online (AJOL)

Introduction: atrial fibrillation is the commonest cardiac rythm disorder. Thromboembolic accidents are common complications that should be prevented by anticoagulant treatment. The aim of our study is to assess the use of vitamins K antagonists in the prevention of thromboembolic risk in atrial fibrillation. Methods: it was a ...

Clinicopathological Risk Factors and Biochemical Predictors of Safe Discharge after Total Thyroidectomy and Central Compartment Node Dissection for Thyroid Cancer: A Prospective Study

Directory of Open Access Journals (Sweden)

Yu-mi Lee

2015-01-01

Full Text Available To determine the clinicopathological risk factors and reliable biochemical predictors of the development of hypocalcemic symptoms after total thyroidectomy on the basis of serum calcium and intact parathyroid hormone (PTH levels measured 1 hour after surgery, a prospective study was performed on 817 patients who underwent a total thyroidectomy with central compartment node dissection (CCND due to well-differentiated thyroid cancer. We evaluated the correlations between hypocalcemic symptom development and clinicopathological factors. And the predictability for hypocalcemic symptom development of intact PTH cut-offs (<10 pg/mL and <20 pg/mL, resp. according to serum calcium level subgroup was analyzed. Female gender (P<0.001 was the only independent risk factor for hypocalcemic symptom development in multivariate regression analysis. The negative predictive value (NPV of intact PTH, signifying nondevelopment of hypocalcemic symptoms, was higher than the positive predictive value (PPV which signified development of hypocalcemic symptoms. In addition, when we applied the different adoption of the intact PTH cut-off according to serum calcium level, we could obtain more increased NPVs. A female gender and the application of more specific cut-offs for intact PTH according to the serum calcium levels measured 1 hour after surgery may help the patients to be more safely discharged.

Case of right atrial myxoma with right to left shunt

Energy Technology Data Exchange (ETDEWEB)

Nakai, Kenji; Suzuki, Tomoyuki; Ohzeki, Tetsuro (Iwate Medical Coll., Morioka (Japan). School of Medicine)

1982-12-01

A case of 49-year-old woman with right atrial myxoma resulting to right to left shunt, diagnosed by cardiac pool isotope image, was reported. She was admitted to our clinic because of progressive shortness of breath. At admission lip cyanosis was noted. Laboratory data included polycythemia, low O/sub 2/ saturation (89%) and high erythrocyte sedimentation rate (65 mm/1 h). Chest x-p showed slight right atrial enlargement, but no pulmonary congestion. The electrocardiogram showed sinus regular rhythm with biphasic p wave in leads II, III, aVf. Although 1st heart sound at the apex was splited, no heart murmur was heard. In usual echocardiographic approach, no abnormal echogram was obtained in the right ventricular region. Lung perfusion scintiscan with Tc-99 m-MAA showed visualization of thyroid gland and kidney, which suggested intracardiac right-to-left shunt. Cardiac pool image with Tc-99m-HSA revealed large photo-deficient area in the right atrium and early visualization of aortic arch. Computor tomography showed large round low density region 8 x 7 cm in size. Based on their findings, this patient was diagnosed as right atrial tumor. At operation a large tumor (diameter 8 x 7 x 7 cm, weight 160g) filled the lower part of the right atrium and was adherent to the anterolateral wall in the right atrium. As a cause of R-L shunt, streched foramen ovale (5 x 10 mm) was found. Tumor histology was typical of atrial myxoma. Post-operative gated cardiac isotope image showed no evidence of residual atrial tumor. Cardiac blood pool isotope imaging was a method for the noninvasive detection and assessment of right atrial myxoma.

Relaxin suppresses atrial fibrillation in aged rats by reversing fibrosis and upregulating Na+ channels.

Science.gov (United States)

Henry, Brian L; Gabris, Beth; Li, Qiao; Martin, Brian; Giannini, Marianna; Parikh, Ashish; Patel, Divyang; Haney, Jamie; Schwartzman, David S; Shroff, Sanjeev G; Salama, Guy

2016-04-01

Atrial fibrillation (AF) contributes significantly to morbidity and mortality in elderly patients and has been correlated with enhanced age-dependent atrial fibrosis. Reversal of atrial fibrosis has been proposed as therapeutic strategy to suppress AF. To test the ability of relaxin to reverse age-dependent atrial fibrosis and suppress AF. Aged F-344 rats (24 months old) were treated with subcutaneous infusion of vehicle or relaxin (0.4 mg/kg/day) for 2 weeks. Rat hearts were excised, perfused on a Langendorff apparatus, and stained with voltage and Ca(2+) indicator dyes. Optical mapping and programmed electrical stimulation was used to test arrhythmia vulnerability and changes in electrophysiological characteristics. Changes in protein expression and Na(+) current density (INa) were measured by tissue immunofluorescence and whole-cell patch clamp technique. In aged rats, sustained AF was readily induced with a premature pulse (n = 7/8) and relaxin treatment suppressed sustained AF by a premature impulse or burst pacing (n = 1/6) (P atrial action potential conduction velocity and decreased atrial fibrosis. Relaxin treatment increased Nav1.5 expression (n = 6; 36% ± 10%) and decreased total collagen and collagen I (n = 5-6; 55%-66% ± 15%) in aged atria (P atrial INa by 46% ± 4% (n = 12-13/group, P atrial conduction velocity by decreasing atrial fibrosis and increasing INa. These data provide compelling evidence that relaxin may serve as an effective therapy to manage AF in geriatric patients by reversing fibrosis and modulating cardiac ionic currents. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

The effects of rhythm control strategies versus rate control strategies for atrial fibrillation and atrial flutter: a protocol for a systematic review with meta-analysis and Trial Sequential Analysis.