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Sample records for arrhythmia

  1. Cardiac arrhythmias

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008407 Effects of sympathetic nerve stimulation on connexin43 and ventricular arrhythmias during acute myocardial ischemia: experiment with rats. HU Xiaorong(胡笑容), et al. Dept Cardiol, Renmin Hosp, Wuhan Univ, Wuhan 430060. Natl Med J China 2008;88(24):1707-1710. Objective To investigate the effects of sympathetic nerve stimulation (SNS) on connexin43 (Cx43) and ventricular arrhythmias during acute myocardial ischemia (MI).

  2. Nonrespiratory Sinus Arrhythmia

    Directory of Open Access Journals (Sweden)

    Barbosa Filho José

    2002-01-01

    Full Text Available We report here 2 cases of sinus arrhythmia considered to be a form of nonrespiratory sinus arrhythmia because they did not have variances in the RR interval sequence within the oscillations modulated by respiration. Because the patients had pulsus alternans similar that observed in bigeminy, and because they did not have signs or symptoms of heart failure, we believe the arrhythmias represent intrinsic alterations of the electric activity of the sinus node

  3. [Alcohol and arrhythmias].

    Science.gov (United States)

    Pfeiffer, D; Jurisch, D; Neef, M; Hagendorff, A

    2016-09-01

    The effects of alcohol on induction of arrhythmias is dose-dependent, independent of preexisting cardiovascular diseases or heart failure and can affect otherwise healthy subjects. While the probability of atrial fibrillation increases with the alcohol dosage, events of sudden cardiac death are less frequent with low and moderate consumption but occur more often in heavy drinkers with alcoholic cardiomyopathy. Men are first affected at higher dosages of alcohol but women can suffer from arrhythmias at lower dosages. Thromboembolisms and ischemic stroke can occur less often at lower dosages of alcohol; however, hemorrhagic stroke and subarachnoid hemorrhage are increased with higher alcohol dosages. Recognizable protective mechanisms of alcohol with respect to cardiovascular diseases only occur with lower amounts of alcohol of less than 10 g per day. Underlying mechanisms explain these controversial effects. Specific therapeutic options for alcohol-related arrhythmias apart from abstinence from alcohol consumption are not known. PMID:27582366

  4. Computers and clinical arrhythmias.

    Science.gov (United States)

    Knoebel, S B; Lovelace, D E

    1983-02-01

    Cardiac arrhythmias are ubiquitous in normal and abnormal hearts. These disorders may be life-threatening or benign, symptomatic or unrecognized. Arrhythmias may be the precursor of sudden death, a cause or effect of cardiac failure, a clinical reflection of acute or chronic disorders, or a manifestation of extracardiac conditions. Progress is being made toward unraveling the diagnostic and therapeutic problems involved in arrhythmogenesis. Many of the advances would not be possible, however, without the availability of computer technology. To preserve the proper balance and purposeful progression of computer usage, engineers and physicians have been exhorted not to work independently in this field. Both should learn some of the other's trade. The two disciplines need to come together to solve important problems with computers in cardiology. The intent of this article was to acquaint the practicing cardiologist with some of the extant and envisioned computer applications and some of the problems with both. We conclude that computer-based database management systems are necessary for sorting out the clinical factors of relevance for arrhythmogenesis, but computer database management systems are beset with problems that will require sophisticated solutions. The technology for detecting arrhythmias on routine electrocardiograms is quite good but human over-reading is still required, and the rationale for computer application in this setting is questionable. Systems for qualitative, continuous monitoring and review of extended time ECG recordings are adequate with proper noise rejection algorithms and editing capabilities. The systems are limited presently for clinical application to the recognition of ectopic rhythms and significant pauses. Attention should now be turned to the clinical goals for detection and quantification of arrhythmias. We should be asking the following questions: How quantitative do systems need to be? Are computers required for the detection of

  5. [Arrhythmias from swallowing].

    Science.gov (United States)

    Palazzuoli, V; Mondillo, S; Faglia, S; D'Aprile, N; De Luca, G; Kristodhullu, A; Corba, E

    1992-01-01

    We describe the case of a 51-year old, non cardiopathic patient, with recurrent attacks of supraventricular tachycardia induced by swallowing. In the existing literature we found several descriptions of hypokinetic arrhythmias, easily explained by a mechanism of vagal inhibition. The cases of predominantly hyperkinetic arrhythmias, however, are much less common. In these patients the origin of the disease seems to be due to sympathetic oesophageal fibers and superior and medium cardiac nerves. In the present case, as in the others reported in the literature, the drug of choice seems to be Amiodarone which appears to be the most effective in preventing tachyarrhythmias caused by swallowing.

  6. [Arrhythmias during pregnancy].

    Science.gov (United States)

    Trappe, H-J

    2008-09-01

    Cardiovascular emergencies are rare during pregnancy with an incidence of 0,2-4,0%. Emergencies include arrhythmias, acute coronary syndrome, peripartum cardiomyopathy and hypertensive disorders. Electrical DC-cardioversion with 50-100 Joules is indicated in the acute treatment of arrhythmias in all patients in an unstable hemodynamic state. If 100 J fails higher energies (up to 360 J) will be necessary. In stable supraventricular tachycardia intravenous adenosine is the first choice drug and may safely terminate the arrhythmia. Ventricular premature beats are frequently present during pregnancy and benign in most patients. However, life-threatening ventricular tachyarrhythmias (sustained ventricular tachycardia [VT], ventricular flutter [VFlt], ventricular fibrillation [VF]) were observed less frequently. Electrical DC-cardioversion is necessary in all pregnant women who are in a hemodynamically unstable state and have a life-threatening ventricular tachyarrhythmias. In hemodynamically stable pregnant women the initial therapy with ajmaline, procainamide or lidocaine is indicated. Implantation of a cardioverter-defibrillator is indicated in patients with syncope caused by VT, VF, VFlt or aborted sudden death. PMID:18767007

  7. Cardiac metabolism and arrhythmias

    OpenAIRE

    Barth, Andreas S.; Tomaselli, Gordon F.

    2009-01-01

    Sudden cardiac death remains a leading cause of mortality in the Western world, accounting for up to 20% of all deaths in the U.S.1, 2 The major causes of sudden cardiac death in adults age 35 and older are coronary artery disease (70–80%) and dilated cardiomyopathy (10–15%).3 At the molecular level, a wide variety of mechanisms contribute to arrhythmias that cause sudden cardiac death, ranging from genetic predisposition (rare mutations and common polymorphisms in ion channels and structural...

  8. Genetic basis of ventricular arrhythmias.

    NARCIS (Netherlands)

    Boussy, T.; Paparella, G.; Asmundis, C. de; Sarkozy, A.; Chierchia, G.B.; Brugada, J.; Brugada, R.; Brugada, P.

    2010-01-01

    Sudden cardiac death caused by malignant ventricular arrhythmias is the most important cause of death in the industrialized world. Most of these lethal arrhythmias occur in the setting of ischemic heart disease. A significant number of sudden deaths, especially in young individuals, are caused by in

  9. Ventricular arrhythmias in Chagas disease

    Directory of Open Access Journals (Sweden)

    Marco Paulo Tomaz Barbosa

    2015-02-01

    Full Text Available Sudden death is one of the most characteristic phenomena of Chagas disease, and approximately one-third of infected patients develop life-threatening heart disease, including malignant ventricular arrhythmias. Fibrotic lesions secondary to chronic cardiomyopathy produce arrhythmogenic substrates that lead to the appearance and maintenance of ventricular arrhythmias. The objective of this study is to discuss the main clinical and epidemiological aspects of ventricular arrhythmias in Chagas disease, the specific workups and treatments for these abnormalities, and the breakthroughs needed to determine a more effective approach to these arrhythmias. A literature review was performed via a search of the PubMed database from 1965 to May 31, 2014 for studies of patients with Chagas disease. Clinical management of patients with chronic Chagas disease begins with proper clinical stratification and the identification of individuals at a higher risk of sudden cardiac death. Once a patient develops malignant ventricular arrhythmia, the therapeutic approach aims to prevent the recurrence of arrhythmias and sudden cardiac death by the use of implantable cardioverter defibrillators, antiarrhythmic drugs, or both. In select cases, invasive ablation of the reentrant circuit causing tachycardia may be useful. Ventricular arrhythmias are important manifestations of Chagas cardiomyopathy. This review highlights the absence of high-quality evidence regarding the treatment of ventricular arrhythmias in Chagas disease. Recognizing high-risk patients who require specific therapies, especially invasive procedures such as the implantation of cardioverter defibrillators and ablative approaches, is a major challenge in clinical practice.

  10. Cardiac arrhythmia classification using autoregressive modeling

    OpenAIRE

    Srinivasan Narayanan; Ge Dingfei; Krishnan Shankar M

    2002-01-01

    Abstract Background Computer-assisted arrhythmia recognition is critical for the management of cardiac disorders. Various techniques have been utilized to classify arrhythmias. Generally, these techniques classify two or three arrhythmias or have significantly large processing times. A simpler autoregressive modeling (AR) technique is proposed to classify normal sinus rhythm (NSR) and various cardiac arrhythmias including atrial premature contraction (APC), premature ventricular contraction (...

  11. Arrhythmias in the Muscular Dystrophies

    OpenAIRE

    Rajdev, Archana; William J Groh

    2015-01-01

    In patients with muscular dystrophies, cardiac involvement leading to cardiomyopathy and arrhythmias occur with variable prevalence mirroring the phenotypic variability seen among and within the various hereditary myopathies. These patients are at risk for development for bradyarrhythmias and tachyarrhythmias including sudden cardiac death. Knowledge of the incidence of arrhythmias and predictors of sudden death in the various hereditary myopathies can help guide screening and appropriate man...

  12. Arrhythmias in the muscular dystrophies.

    Science.gov (United States)

    Rajdev, Archana; Groh, William J

    2015-06-01

    In patients with muscular dystrophies, cardiac involvement leading to cardiomyopathy and arrhythmias occurs with variable prevalence, mirroring the phenotypic variability seen among and within the various hereditary myopathies. Knowledge of the incidence of arrhythmias and predictors of sudden death in the various hereditary myopathies can help guide screening and appropriate management of these patients, thereby improving survival. The noncardiac manifestations can lead to delayed recognition of symptoms, affect the decision to implant a prophylactic device, and once a decision is made to proceed with device implant, increase peri-procedural respiratory and anesthesia-related complications. PMID:26002394

  13. Pharmacological management of arrhythmias in the elderly

    NARCIS (Netherlands)

    VanGelder, IC; Brugemann, J; Crijns, HJGM

    1997-01-01

    The incidence of cardiac arrhythmia increases with advancing age, as does the prevalence of structural heart disease. Serious arrhythmias, such as sustained ventricular tachycardias, are uncommon in elderly patients, but nonsustained ventricular tachycardias and atrial fibrillation are relatively fr

  14. Improved arrhythmia detection in implantable loop recorders

    DEFF Research Database (Denmark)

    Brignole, M.; Black, C.L.B.; Sutton, R.;

    2008-01-01

    Improved Arrhythmia Detection. Introduction: Implantable loop recorders (ILR) have an automatic arrhythmia detection feature that can be compromised by inappropriately detected episodes. This study evaluated a new ILR sensing and detection scheme for automatically detecting asystole...

  15. Cardioverter-Defibrillator: A Treatment for Arrhythmia

    Science.gov (United States)

    MENU Return to Web version Arrhythmia | Cardioverter-Defibrillator: A Treatment for Arrhythmia What is an implantable cardioverter-defibrillator? An implantable cardioverter-defibrillator (often called an ICD) is a device that keeps ...

  16. Fuzzy Soft System and Arrhythmia Classification

    OpenAIRE

    Pankaj Srivastava; Neeraja Sharma; Aparna, C. S.

    2014-01-01

    An arrhythmia is an irregularity with the speed or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm. Most arrhythmias are harmless, but some can be serious or even life threatening. The present paper deals with the classification scheme of arrhythmia commonly occurring in human beings of Southeast Asian countries. Medical knowledge used in practice has been closely studied for modelling user friendly referral system to sharpen a...

  17. Molecular therapies for cardiac arrhythmias

    NARCIS (Netherlands)

    G.J.J. Boink

    2013-01-01

    Despite the ongoing advances in pharmacology, devices and surgical approaches to treat heart rhythm disturbances, arrhythmias are still a significant cause of death and morbidity. With the introduction of gene and cell therapy, new avenues have arrived for the local modulation of cardiac disease. Th

  18. Arrhythmia risk in liver cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Ioana Mozos

    2015-01-01

    Interactions between the functioning of the heart andthe liver have been described, with heart diseasesaffecting the liver, liver diseases affecting the heart,and conditions that simultaneously affect both. Theheart is one of the most adversely affected organs inpatients with liver cirrhosis. For example, arrhythmiasand electrocardiographic changes are observed inpatients with liver cirrhosis. The risk for arrhythmia isinfluenced by factors such as cirrhotic cardiomyopathy,cardiac ion channel remodeling, electrolyte imbalances,impaired autonomic function, hepatorenal syndrome, metabolic abnormalities, advanced age, inflammatory syndrome, stressful events, impaired drug metabolism and comorbidities. Close monitoring of cirrhotic patients is needed for arrhythmias, particularly when QT intervalprolonging drugs are given, or if electrolyte imbalances or hepatorenal syndrome appear. Arrhythmia risk may persist after liver transplantation due to possible QT interval prolongation, persistence of the parasympathetic impairment, post-transplant reperfusion and chronic immunosuppression, as well as consideration of the fact that the transplant itself is a stressful event for the cardiovascular system. The aims of the present article were to provide a review of the most important data regarding the epidemiology, pathophysiology, and biomarkers of arrhythmia risk in patients with liver cirrhosis, to elucidate the association with long-term outcome, and to propose future research directions.

  19. [Maternal arrhythmias during pregnancy. Practical review].

    Science.gov (United States)

    Kornacewicz-Jach, Zdzisława; Peregud-Pogorzelska, Małgorzata

    2014-01-01

    Pregnancy is accompanied by a variety of cardiovascular changes in normal women, and these changes can increased incidence of maternal cardiac arrhythmias. Supraventricular and ventricular arrhythmias reguiring treatment are rarely seen during pregnancy in healthy women. Structural cardiac defects or residual defects after repair may contribute to the occurrence of clinically relevant arrhythmias. Arrhythmias during pregnancy include a wide spectrum. The most common are simple ventricular and atrial ectopy, sinusal tachycardia and supraventricular tachycardia. The foetus may suffer both haemodynamic alternations and adverse effects of the treatment (teratogenic risk, foetal growth and development). The management of arrhythmias in pregnant women is similar to that taken in patients who are not pregnant.

  20. Remote Arrhythmia Monitoring System Developed

    Science.gov (United States)

    York, David W.; Mackin, Michael A.; Liszka, Kathy J.; Lichter, Michael J.

    2004-01-01

    Telemedicine is taking a step forward with the efforts of team members from the NASA Glenn Research Center, the MetroHealth campus of Case Western University, and the University of Akron. The Arrhythmia Monitoring System is a completed, working test bed developed at Glenn that collects real-time electrocardiogram (ECG) signals from a mobile or homebound patient, combines these signals with global positioning system (GPS) location data, and transmits them to a remote station for display and monitoring. Approximately 300,000 Americans die every year from sudden heart attacks, which are arrhythmia cases. However, not all patients identified at risk for arrhythmias can be monitored continuously because of technological and economical limitations. Such patients, who are at moderate risk of arrhythmias, would benefit from technology that would permit long-term continuous monitoring of electrical cardiac rhythms outside the hospital environment. Embedded Web Technology developed at Glenn to remotely command and collect data from embedded systems using Web technology is the catalyst for this new telemetry system (ref. 1). In the end-to-end system architecture, ECG signals are collected from a patient using an event recorder and are transmitted to a handheld personal digital assistant (PDA) using Bluetooth, a short-range wireless technology. The PDA concurrently tracks the patient's location via a connection to a GPS receiver. A long distance link is established via a standard Internet connection over a 2.5-generation Global System for Mobile Communications/General Packet Radio Service (GSM/GPRS)1 cellular, wireless infrastructure. Then, the digital signal is transmitted to a call center for monitoring by medical professionals.

  1. Genetic Basis of Ventricular Arrhythmias

    OpenAIRE

    Pazoki, Raha; Wilde, Arthur A. M.; Connie R Bezzina

    2010-01-01

    Sudden cardiac death (SCD) is a leading cause of total and cardiovascular mortality, and ventricular fibrillation is the underlying arrhythmia in the majority of cases. In the young, where the incidence of SCD is low, a great proportion of SCDs occur in the context of inherited disorders such as cardiomyopathy or primary electrical disease, where a monogenic hereditary component is a strong determinant of risk. Marked advancement has been made over the past 15 years in the understanding of th...

  2. 10.2.Cardiac arrhythmias

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930257 Electrophysiologic study of reperfu-sion arrhythmias.YIN Hong (尹红),et al.Af-fil Hosp,Shandong Med Univ,Jinan.Chin CirJ 1993;8(1):37—39.Twenty dogs of experimental ischemic reper-fusion were studied with a three-dimensionalmapping system of cardiac electric activity andmultiple—level myocardial recordings by bipolarplunge—needle electrodes.27% of the nonsus-tained ventricular tachycardia (NSVT) of intra-mural reentry occurred in the ischemic subendo-

  3. Arrhythmia

    Science.gov (United States)

    ... travels, it causes the heart to contract and pump blood. Each electrical signal begins in a group of ... atria. This causes the atria to contract and pump blood into the heart's two lower chambers, the ventricles ( ...

  4. Arrhythmias

    Science.gov (United States)

    ... Atrial myxoma Cardiac ablation procedures Heart attack Heart failure - overview Heart pacemaker Pulse Stroke Patient Instructions Atrial fibrillation - discharge Heart pacemaker - discharge Taking warfarin (Coumadin, Jantoven) - ...

  5. Atrial Arrhythmia Summit: Post Summit Report

    Science.gov (United States)

    Barr, Yael

    2010-01-01

    The Atrial Arrhythmia Summit brought together nationally and internationally recognized experts in cardiology, electrophysiology, exercise physiology, and space medicine in an effort to elucidate the mechanisms, risk factors, and management of atrial arrhythmias in the unique occupational cohort of the U.S. astronaut corps.

  6. Arrhythmia and exercise intolerance in Fontan patients

    DEFF Research Database (Denmark)

    Idorn, L; Juul, K; Jensen, A S;

    2013-01-01

    BACKGROUND: Long-term survival after the Fontan procedure shows excellent results but is associated with a persistent risk of arrhythmias and exercise intolerance. We aimed to analyze the current burden of clinically relevant arrhythmia and severe exercise intolerance in Danish Fontan patients...... and estimated to 99.1% per year. Prevalence of clinically relevant arrhythmia and severe exercise intolerance increased significantly with age and was found in 32% and 85% of patients ≥20years, respectively. Thus, from survival data and logistic regression models the future prevalence of patients, clinically...... relevant arrhythmia and severe exercise intolerance were estimated, revealing a considerable augmentation. Furthermore, resting and maximum cardiac index, resting stroke volume index and pulmonary diffusing capacity decreased significantly with age while diastolic and systolic ventricular function...

  7. Cardiac arrhythmias during or after epileptic seizures

    Science.gov (United States)

    van der Lende, Marije; Surges, Rainer; Sander, Josemir W; Thijs, Roland D

    2016-01-01

    Seizure-related cardiac arrhythmias are frequently reported and have been implicated as potential pathomechanisms of Sudden Unexpected Death in Epilepsy (SUDEP). We attempted to identify clinical profiles associated with various (post)ictal cardiac arrhythmias. We conducted a systematic search from the first date available to July 2013 on the combination of two terms: ‘cardiac arrhythmias’ and ‘epilepsy’. The databases searched were PubMed, Embase (OVID version), Web of Science and COCHRANE Library. We attempted to identify all case reports and case series. We identified seven distinct patterns of (post)ictal cardiac arrhythmias: ictal asystole (103 cases), postictal asystole (13 cases), ictal bradycardia (25 cases), ictal atrioventricular (AV)-conduction block (11 cases), postictal AV-conduction block (2 cases), (post)ictal atrial flutter/atrial fibrillation (14 cases) and postictal ventricular fibrillation (3 cases). Ictal asystole had a mean prevalence of 0.318% (95% CI 0.316% to 0.320%) in people with refractory epilepsy who underwent video-EEG monitoring. Ictal asystole, bradycardia and AV-conduction block were self-limiting in all but one of the cases and seen during focal dyscognitive seizures. Seizure onset was mostly temporal (91%) without consistent lateralisation. Postictal arrhythmias were mostly found following convulsive seizures and often associated with (near) SUDEP. The contrasting clinical profiles of ictal and postictal arrhythmias suggest different pathomechanisms. Postictal rather than ictal arrhythmias seem of greater importance to the pathophysiology of SUDEP. PMID:26038597

  8. Cardiac arrhythmia classification using autoregressive modeling

    Directory of Open Access Journals (Sweden)

    Srinivasan Narayanan

    2002-11-01

    Full Text Available Abstract Background Computer-assisted arrhythmia recognition is critical for the management of cardiac disorders. Various techniques have been utilized to classify arrhythmias. Generally, these techniques classify two or three arrhythmias or have significantly large processing times. A simpler autoregressive modeling (AR technique is proposed to classify normal sinus rhythm (NSR and various cardiac arrhythmias including atrial premature contraction (APC, premature ventricular contraction (PVC, superventricular tachycardia (SVT, ventricular tachycardia (VT and ventricular fibrillation (VF. Methods AR Modeling was performed on ECG data from normal sinus rhythm as well as various arrhythmias. The AR coefficients were computed using Burg's algorithm. The AR coefficients were classified using a generalized linear model (GLM based algorithm in various stages. Results AR modeling results showed that an order of four was sufficient for modeling the ECG signals. The accuracy of detecting NSR, APC, PVC, SVT, VT and VF were 93.2% to 100% using the GLM based classification algorithm. Conclusion The results show that AR modeling is useful for the classification of cardiac arrhythmias, with reasonably high accuracies. Further validation of the proposed technique will yield acceptable results for clinical implementation.

  9. Cardiac arrhythmias associated with spinal cord injury

    DEFF Research Database (Denmark)

    Hector, Sven Magnus; Biering-Sørensen, Tor; Krassioukov, Andrei;

    2013-01-01

    describing the chronic phase of SCI, showed that individuals with SCI did not have a higher incidence of cardiac arrhythmias compared with able-bodied controls. Furthermore, their heart rate did not differ significantly. Penile vibro-stimulation was the procedure investigated most likely to cause bradycardia......CONTEXT/OBJECTIVES: To review the current literature to reveal the incidence of cardiac arrhythmias and its relation to spinal cord injury (SCI). METHODS: Data source: MEDLINE database, 304 hits, and 32 articles were found to be relevant. The relevant articles all met the inclusion criteria: (1......) contained original data (2) on cardiac arrhythmias (3) in humans with (4) traumatic SCI. RESULTS: In the acute phase of SCI (1-14 days after injury) more cranial as well as more severe injuries seemed to increase the incidence of bradycardia. Articles not covering the first 14 days after injury, thus...

  10. Cardiac arrhythmia as initial presentation of aneurysmal subarachnoid hemorrhage

    NARCIS (Netherlands)

    van der Kleij, FGH; Henselmans, JML; van de Loosdrecht, AA

    1999-01-01

    Cardiac arrhythmia and sudden death are most frequently caused by preexisting heart disease. Rarely, cardiac arrhythmia is a first symptom of an acute neurological event. We describe a patient with asystole and other cardiac arrhythmias, as initial symptoms of acute aneurysmal subarachnoid hemorrhag

  11. A vertical approach to cardiac arrhythmias.

    Science.gov (United States)

    Vaughan Williams, E M

    1987-10-01

    Study of cardiac arrhythmia may be pursued vertically, as up the rungs of a ladder, from symptom to ECG, to EPS, to local lesion, to intracellular metabolism and to alterations of the latter and their effects on charge-transfer by ions across the cell membrane. Raised intracellular cAMP and calcium concentrations are responses to normal physiological controls, and highly abnormal ECGs occur in normal people under stress without progressing to life threatening arrhythmias, yet do so in susceptible individuals. Conversely, appropriate stimulation can precipitate ventricular fibrillation in normal myocardium. Selective stimulation of different types of adrenoceptor has differing electrophysiological effects. Beta 1-adrenoceptors increase contraction and calcium current, and shorten action potential duration (APD) by increasing potassium conductance. Beta 2-adrenoceptors do not increase calcium entry, but shorten APD by stimulating electrogenic Na/K pumping, alpha-adrenoceptors prolong contractions and lengthen APD. It is suggested that the tachycardia, extrasystoles and shortening of APD occurring in response to adrenergic stimuli and hypoxia, are accessory factors, not primary causes, in the development of arrhythmias, and constitute a danger when there is an appropriate anatomical substrate for re-entry. Serious arrhythmias are of multifactorial origin, of which "calcium overload" is but one, not proven to be a frequent one.

  12. Fetal cardiac arrhythmias: diagnosis and management.

    Science.gov (United States)

    Feit, L R

    2001-05-01

    The diagnosis and management of fetal cardiac arrhythmias requires complex skills and knowledge, and has had a great impact on the care of infants with congenital heart disease and their families. Optimal benefits will be derived from a thoughtful team approach, with skillful internal communication, and especially when parental involvement is encouraged in the decision making process. PMID:11392955

  13. Cardiac Arrhythmias and Abnormal Electrocardiograms After Acute Stroke.

    Science.gov (United States)

    Ruthirago, Doungporn; Julayanont, Parunyou; Tantrachoti, Pakpoom; Kim, Jongyeol; Nugent, Kenneth

    2016-01-01

    Cardiac arrhythmias and electrocardiogram (ECG) abnormalities occur frequently but are often underrecognized after strokes. Acute ischemic and hemorrhagic strokes in some particular area of brain can disrupt central autonomic control of the heart, precipitating cardiac arrhythmias, ECG abnormalities, myocardial injury and sometimes sudden death. Identification of high-risk patients after acute stroke is important to arrange appropriate cardiac monitoring and effective management of arrhythmias, and to prevent cardiac morbidity and mortality. More studies are needed to better clarify pathogenesis, localization of areas associated with arrhythmias and practical management of arrhythmias and abnormal ECGs after acute stroke. PMID:26802767

  14. Robotic magnetic navigation for ablation of human arrhythmias

    Science.gov (United States)

    Da Costa, Antoine; Guichard, Jean Baptiste; Roméyer-Bouchard, Cécile; Gerbay, Antoine; Isaaz, Karl

    2016-01-01

    Radiofrequency treatment represents the first choice of treatment for arrhythmias, in particular complex arrhythmias and especially atrial fibrillation, due to the greater benefit/risk ratio compared to antiarrhythmic drugs. However, complex arrhythmias such as atrial fibrillation require long procedures with additional risks such as X-ray exposure or serious complications such as tamponade. Given this context, the treatment of arrhythmias using robotic magnetic navigation entails a technique well suited to complex arrhythmias on account of its efficacy, reliability, significant reduction in X-ray exposure for both patient and operator, as well as a very low risk of perforation. As ongoing developments will likely improve results and procedure times, this technology will become one of the most modern technologies for treating arrhythmias. Based on the literature, this review summarizes the advantages and limitations of robotic magnetic navigation for ablation of human arrhythmias. PMID:27698569

  15. Risk of arrhythmia induced by psychotropic medications

    DEFF Research Database (Denmark)

    Fanoe, Søren; Kristensen, Diana; Fink-Jensen, Anders;

    2014-01-01

    with psychotropic medications. The algorithm integrates the risk categories of the individual drugs and pre-disposing risk factors and suggests a prudent follow-up for patients with an increased risk. We believe this clinically manageable guideline might improve safety in the many and rapidly increasing number......Several drugs used in the treatment of mental diseases are associated with an increased risk of sudden cardiac death (SCD). A general cause-relationship between the intake of these drugs and SCD is unattainable, but numerous case reports of drug-induced malignant arrhythmia and epidemiological...... studies, associating the use of specific drugs with SCD, strongly support the presence of an increased risk. Whereas the absolute risk of drug-induced life-threatening arrhythmia may be relatively low, even small increments in risk of SCD may have a major health impact considering that millions...

  16. Cardiac autonomic nerve distribution and arrhythmia

    Institute of Scientific and Technical Information of China (English)

    Quan Liu; Dongmei Chen; Yonggang Wang; Xin Zhao; Yang Zheng

    2012-01-01

    OBJECTIVE: To analyze the distribution characteristics of cardiac autonomic nerves and to explore the correlation between cardiac autonomic nerve distribution and arrhythmia.DATA RETRIEVAL: A computer-based retrieval was performed for papers examining the distribution of cardiac autonomic nerves, using "heart, autonomic nerve, sympathetic nerve, vagus nerve, nerve distribution, rhythm and atrial fibrillation" as the key words.SELECTION CRITERIA: A total of 165 studies examining the distribution of cardiac autonomic nerve were screened, and 46 of them were eventually included.MAIN OUTCOME MEASURES: The distribution and characteristics of cardiac autonomic nerves were observed, and immunohistochemical staining was applied to determine the levels of tyrosine hydroxylase and acetylcholine transferase (main markers of cardiac autonomic nerve distribution). In addition, the correlation between cardiac autonomic nerve distribution and cardiac arrhythmia was investigated.RESULTS: Cardiac autonomic nerves were reported to exhibit a disordered distribution in different sites, mainly at the surface of the cardiac atrium and pulmonary vein, forming a ganglia plexus. The distribution of the pulmonary vein autonomic nerve was prominent at the proximal end rather than the distal end, at the upper left rather than the lower right, at the epicardial membrane rather than the endocardial membrane, at the left atrium rather than the right atrium, and at the posterior wall rather than the anterior wall. The main markers used for cardiac autonomic nerves were tyrosine hydroxylase and acetylcholine transferase. Protein gene product 9.5 was used to label the immunoreactive nerve distribution, and the distribution density of autonomic nerves was determined using a computer-aided morphometric analysis system.CONCLUSION: The uneven distribution of the cardiac autonomic nerves is the leading cause of the occurrence of arrhythmia, and the cardiac autonomic nerves play an important role in the

  17. Arrhythmia discrimination using a smart phone.

    Science.gov (United States)

    Chong, Jo Woon; Esa, Nada; McManus, David D; Chon, Ki H

    2015-05-01

    We hypothesize that our smartphone-based arrhythmia discrimination algorithm with data acquisition approach reliably differentiates between normal sinus rhythm (NSR), atrial fibrillation (AF), premature ventricular contractions (PVCs) and premature atrial contraction (PACs) in a diverse group of patients having these common arrhythmias. We combine root mean square of successive RR differences and Shannon entropy with Poincare plot (or turning point ratio method) and pulse rise and fall times to increase the sensitivity of AF discrimination and add new capabilities of PVC and PAC identification. To investigate the capability of the smartphone-based algorithm for arrhythmia discrimination, 99 subjects, including 88 study participants with AF at baseline and in NSR after electrical cardioversion, as well as seven participants with PACs and four with PVCs were recruited. Using a smartphone, we collected 2-min pulsatile time series from each recruited subject. This clinical application results show that the proposed method detects NSR with specificity of 0.9886, and discriminates PVCs and PACs from AF with sensitivities of 0.9684 and 0.9783, respectively. PMID:25838530

  18. Cardiac Arrhythmia Classification by Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Hadji Salah

    2015-05-01

    Full Text Available Cardiovascular diseases are the major public health parameter; they are the leading causes of mortality in the world. In fact many studies have been implemented to reduce the risk, including promoting education, prevention, and monitoring of patients at risk. In this paper we propose to develop classification system heartbeats. This system is based mainly on Wavelet Transform to extract features and Kohonen self-organization map the arrhythmias are considered in this study: N,(Normal, V(PrematureVentricular, A(AtrialPremature, S(Extrasystolesupraventriculaire, F(FusionN+S, R(RightBundle Branch.

  19. Loperamide Induced Life Threatening Ventricular Arrhythmia

    Science.gov (United States)

    Bodar, Vijaykumar; Singh, Sharanjit; Frumkin, William; Mangla, Aditya; Doshi, Kaushik

    2016-01-01

    Loperamide is over-the-counter antidiarrheal agent acting on peripherally located μ opioid receptors. It is gaining popularity among drug abusers as opioid substitute. We report a case of a 46-year-old male that was presented after cardiac arrest. After ruling out ischemia, cardiomyopathy, pulmonary embolism, central nervous system pathology, sepsis, and other drug toxicity, we found out that patient was using around 100 mg of Loperamide to control his chronic diarrhea presumably because of irritable bowel syndrome for last five years and consumed up to 200 mg of Loperamide daily for last two days before the cardiac arrest. We hypothesize that the patient's QTc prolongation and subsequent cardiac arrest are due to Loperamide toxicity. Patient experienced gradual resolution of tachyarrhythmia and gradual decrease in QTc interval during hospitalization which supports the evidence of causal relationship between Loperamide overdose and potentially fatal arrhythmias. It also provided the clue that patient may have congenital long QT syndrome which was unmasked by Loperamide causing ventricular arrhythmias. This case adds one more pearl in the literature to support that Loperamide overdose related cardiac toxicity does exist and it raises concerns over Loperamide abuse in the community.

  20. Genetics of inherited primary arrhythmia disorders

    Directory of Open Access Journals (Sweden)

    Spears DA

    2015-09-01

    Full Text Available Danna A Spears, Michael H Gollob Division of Cardiology – Electrophysiology, University Health Network, Toronto General Hospital, Toronto, ON, Canada Abstract: A sudden unexplained death is felt to be due to a primary arrhythmic disorder when no structural heart disease is found on autopsy, and there is no preceding documentation of heart disease. In these cases, death is presumed to be secondary to a lethal and potentially heritable abnormality of cardiac ion channel function. These channelopathies include congenital long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, and short QT syndrome. In certain cases, genetic testing may have an important role in supporting a diagnosis of a primary arrhythmia disorder, and can also provide prognostic information, but by far the greatest strength of genetic testing lies in the screening of family members, who may be at risk. The purpose of this review is to describe the basic genetic and molecular pathophysiology of the primary inherited arrhythmia disorders, and to outline a rational approach to genetic testing, management, and family screening. Keywords: long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, short QT syndrome, genetics

  1. Loperamide Induced Life Threatening Ventricular Arrhythmia.

    Science.gov (United States)

    Upadhyay, Ankit; Bodar, Vijaykumar; Malekzadegan, Mohammad; Singh, Sharanjit; Frumkin, William; Mangla, Aditya; Doshi, Kaushik

    2016-01-01

    Loperamide is over-the-counter antidiarrheal agent acting on peripherally located μ opioid receptors. It is gaining popularity among drug abusers as opioid substitute. We report a case of a 46-year-old male that was presented after cardiac arrest. After ruling out ischemia, cardiomyopathy, pulmonary embolism, central nervous system pathology, sepsis, and other drug toxicity, we found out that patient was using around 100 mg of Loperamide to control his chronic diarrhea presumably because of irritable bowel syndrome for last five years and consumed up to 200 mg of Loperamide daily for last two days before the cardiac arrest. We hypothesize that the patient's QTc prolongation and subsequent cardiac arrest are due to Loperamide toxicity. Patient experienced gradual resolution of tachyarrhythmia and gradual decrease in QTc interval during hospitalization which supports the evidence of causal relationship between Loperamide overdose and potentially fatal arrhythmias. It also provided the clue that patient may have congenital long QT syndrome which was unmasked by Loperamide causing ventricular arrhythmias. This case adds one more pearl in the literature to support that Loperamide overdose related cardiac toxicity does exist and it raises concerns over Loperamide abuse in the community. PMID:27547470

  2. Respiratory arrhythmia in the hearts of harbour porpoises (Phocoena phocoena)

    NARCIS (Netherlands)

    Kastelein, R.A.; Meijler, F.L.

    1989-01-01

    The heart rates of 3 Harbour porpoises (recorded for 26 days) showed individual variation. Electrocardiograms of two of these animals, made while they were on land, showed respiratory arrhythmia. The heart rate dropped when the animals were returned to the water, but the arrhythmia remained.

  3. Atrial Arrhythmias and Their Implications for Space Flight - Introduction

    Science.gov (United States)

    Polk, J. D.; Barr, Y. R.; Bauer, P.; Hamilton, D. R.; Kerstman, E.; Tarver, B.

    2010-01-01

    This panel will discuss the implications of atrial arrhythmias in astronauts from a variety of perspectives; including historical data, current practices, and future challenges for exploration class missions. The panelists will present case histories, outline the evolution of current NASA medical standards for atrial arrhythmias, discuss the use of predictive tools, and consider potential challenges for current and future missions.

  4. Arrhythmia in Acute Right Ventricular Infarction

    Directory of Open Access Journals (Sweden)

    Azin Alizadeh Asl

    2007-09-01

    Full Text Available Acute inferior myocardial infarction (MI frequently involves the right ventricle (RV.1-3 We assessed the prognostic impact of RV myocardial involvement in patients with inferior MI. One hundred seventy patients were admitted to the cardiac care unit of Madani Heart Hospital (Tabriz-Iran with the diagnosis of inferior MI with (group1 or without (group2 the simultaneous involvement of RV during the study period (from 2005 to 2006. Patients presenting within 12h of symptom onset were eligible for inclusion. Patients with simultaneous anterior wall MI or renal impairment (creatinine > 2 mg/dl, as well as those undergoing primary percutaneous translational coronary angioplasty, were excluded. Eighty eight percent of the patients with RVMI and 75% of those with isolated inferior MI had some type of arrhythmia. Atrioventricular (AV block occurred in 42% of the infarctions with RV involvement and only in 29% of the control group. Intra-ventricular conduction disturbance (IVCD was also more frequent in RVMI (29.4% vs. 13.1%, p=0.021, especially right bundle branch block (RBBB (20% vs. 7.4%, P=0.003. There was, however, no meaningful difference in the incidence of left bundle branch block (LBBB between the two groups (3.5% vs. 2.35%, P=0.95. Ventricular fibrillation (VF was observed in 5.2% and 1.2% and ventricular tachycardia in 26% and 12.2% of the patients in groups 1 and 2, respectively. In 27% of patients with RVMI, it was necessary to implant a pacemaker as compared to 10% of those in the control group. Mortality was higher in the patients with inferior infarction extended to the RV (15.3% vs. 3.5%, P= 0.0001. Thus, the differences between the findings in the two groups in terms of the occurrence of post-MI arrhythmias and conduction disorders were quite significant, but there was no meaningful difference with respect to the incidence of LBBB between the two groups. Additionally, patients with inferior MI who also had RV myocardial involvement were

  5. MicroRNAs in cardiac arrhythmia

    DEFF Research Database (Denmark)

    Hedley, Paula L; Carlsen, Anting L; Christiansen, Kasper M;

    2014-01-01

    Long QT syndrome (LQTS) is a genetic cardiac condition associated with prolonged ventricular repolarization, primarily a result of perturbations in cardiac ion channels, which predisposes individuals to life-threatening arrhythmias. Using DNA screening and sequencing methods, over 700 different...... LQTS-causing mutations have been identified in 13 genes worldwide. Despite this, the genetic cause of 30-50% of LQTS is presently unknown. MicroRNAs (miRNAs) are small (∼ 22 nucleotides) noncoding RNAs which post-transcriptionally regulate gene expression by binding complementary sequences within...... cardiovascular diseases. MiR-1 and MiR-133A are the most abundant miRNAs in the heart and have both been reported to regulate cardiac ion channels. We hypothesized that, as a consequence of their role in regulating cardiac ion channels, genetic variation in the genes which encode MiR-1 and MiR-133A might explain...

  6. Effects of Heterogeneous Diffuse Fibrosis on Arrhythmia Dynamics and Mechanism.

    Science.gov (United States)

    Kazbanov, Ivan V; ten Tusscher, Kirsten H W J; Panfilov, Alexander V

    2016-01-01

    Myocardial fibrosis is an important risk factor for cardiac arrhythmias. Previous experimental and numerical studies have shown that the texture and spatial distribution of fibrosis may play an important role in arrhythmia onset. Here, we investigate how spatial heterogeneity of fibrosis affects arrhythmia onset using numerical methods. We generate various tissue textures that differ by the mean amount of fibrosis, the degree of heterogeneity and the characteristic size of heterogeneity. We study the onset of arrhythmias using a burst pacing protocol. We confirm that spatial heterogeneity of fibrosis increases the probability of arrhythmia induction. This effect is more pronounced with the increase of both the spatial size and the degree of heterogeneity. The induced arrhythmias have a regular structure with the period being mostly determined by the maximal local fibrosis level. We perform ablations of the induced fibrillatory patterns to classify their type. We show that in fibrotic tissue fibrillation is usually of the mother rotor type but becomes of the multiple wavelet type with increase in tissue size. Overall, we conclude that the most important factor determining the formation and dynamics of arrhythmia in heterogeneous fibrotic tissue is the value of maximal local fibrosis. PMID:26861111

  7. Sinoatrial node dysfunction induces cardiac arrhythmias in diabetic mice

    DEFF Research Database (Denmark)

    Soltysinska, Ewa; Speerschneider, Tobias; Winther, Sine V;

    2014-01-01

    recovery time was prolonged in diabetic mice. Adrenoreceptor stimulation increased heart rate in all mice and elicited cardiac arrhythmias in db/db mice only. The arrhythmias emanated from the SAN and were characterized by large RR fluctuations. Moreover, nerve density was reduced in the SAN region.......ConclusionsEnhanced systolic function and reduced diastolic function indicates early ventricular remodeling in obese and diabetic mice. They have SAN dysfunction, and adrenoreceptor stimulation triggers cardiac arrhythmia originating in the SAN. Thus, dysfunction of the intrinsic cardiac pacemaker and remodeling...

  8. Arrhythmias in Adult Congenital Heart Disease: Diagnosis and Management.

    Science.gov (United States)

    Kumar, Saurabh; Tedrow, Usha B; Triedman, John K

    2015-11-01

    Cardiac arrhythmias are a major source of morbidity and mortality in adults with CHD. A multidisciplinary approach in a center specializing in the care of ACHD is most likely to have the expertise needed provide this care. Knowledge of the underlying anatomy, mechanism of arrhythmia, and potential management strategies is critical, as well as access and expertise in the use of advanced imaging and ablative technologies. Future challenges in management include refining the underlying mechanism and putative ablation targets for catheter ablation of AF, an arrhythmia rapidly rising in prevalence in this population.

  9. Cardiac arrhythmias during exercise testing in healthy men.

    Science.gov (United States)

    Beard, E. F.; Owen, C. A.

    1973-01-01

    Clinically healthy male executives who participate in a long-term physical conditioning program have demonstrated cardiac arrhythmia during and after periodic ergometric testing at submaximal and maximal levels. In 1,385 tests on 248 subjects, it was found that 34% of subjects demonstrated an arrhythmia at some time and 13% of subjects developed arrhythmia on more than one test. Premature systoles of ventricular origin were most common, but premature systoles of atrial origin, premature systoles of junctional origin, paroxysmal atrial tachycardia, atrioventricular block, wandering pacemaker, and pre-excitation were also seen. Careful post-test monitoring and pulse rate regulated training sessions are suggested for such programs.

  10. Mechanisms of ventricular arrhythmias: from molecular fluctuations to electrical turbulence.

    Science.gov (United States)

    Qu, Zhilin; Weiss, James N

    2015-01-01

    Ventricular arrhythmias have complex causes and mechanisms. Despite extensive investigation involving many clinical, experimental, and computational studies, effective biological therapeutics are still very limited. In this article, we review our current understanding of the mechanisms of ventricular arrhythmias by summarizing the state of knowledge spanning from the molecular scale to electrical wave behavior at the tissue and organ scales and how the complex nonlinear interactions integrate into the dynamics of arrhythmias in the heart. We discuss the challenges that we face in synthesizing these dynamics to develop safe and effective novel therapeutic approaches. PMID:25340965

  11. [Idiopathic ventricular tachycardia, an arrhythmia with good prognosis].

    NARCIS (Netherlands)

    Camaro, C.; Bos, H.S.; Smeets, J.L.R.M.

    2010-01-01

    Three patients, one experiencing palpitations and two complaining of chest pain in stressful situations, appeared to have monomorphic wide complex tachycardia. After excluding channelopathy, structural abnormalities and ischaemia of the heart, this arrhythmia was classified as idiopathic. Symptoms d

  12. 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.

  13. Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study

    Directory of Open Access Journals (Sweden)

    Fatima Dumas Cintra

    2014-11-01

    Full Text Available Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart® system. Results: A total of 767 participants (461 men with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001. After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.

  14. Psychological Distress and Arrhythmia: Risk Prediction and Potential Modifiers

    OpenAIRE

    Peacock, James; Whang, William

    2013-01-01

    The connection between the heart and the brain has long been anecdotally recognized but systematically studied only relatively recently. Cardiac arrhythmias, especially sudden cardiac death, remain a major public health concern and there is mounting evidence that psychological distress plays a critical role as both a predictor of high-risk cardiac substrate and as an inciting trigger. The transient, unpredictable nature of emotions and cardiac arrhythmias have made their study challenging, bu...

  15. Cardiovascular profiles of scleroderma patients with arrhythmias and conduction disorders.

    Science.gov (United States)

    Muresan, L; Petcu, A; Pamfil, C; Muresan, C; Rinzis, M; Mada, R O; Gusetu, G N; Pop, D; Zdrenghea, D; Rednic, S

    2016-01-01

    Introduction Arrhythmias and conduction disorders are common among patients with scleroderma. Their early identification is important, since scleroderma patients with arrhythmias have a higher mortality risk compared with scleroderma patients without arrhythmias. The aim of this study was to characterize the cardiovascular profiles of scleroderma patients with different types of arrhythmias and conduction disorders. Methods One hundred and ten consecutive patients with a diagnosis of systemic sclerosis according to the ACR criteria were included in the study. Patients underwent a 12-lead ECG and a 24-hour Holter ECG monitoring for arrhythmias and conduction disorders identification. Blood sample testing, echocardiography, spirometry, chest X-ray and, when considered appropriate, high resolution chest CT were also performed. A subgroup of 21 patients underwent NT-pro BNP level measurements. Patients' clinical and para-clinical characteristics were compared according to the presence or absence of arrhythmias and conduction disorders. Results The prevalence of arrhythmia and conduction disturbances was 60.9%. Patients with such disorders were older (54.4 ± 13.3 vs. 49.7 ± 10.1 years, p=0.05), had a higher prevalence of pulmonary hypertension (p=0.008), valve disease (p < 0.001), especially mitral and tricuspid regurgitation, chamber enlargement on echocardiography (left atrial and right ventricular, p = 0.012 and 0.005, respectively) as well as higher NT-pro BNP levels: 265.5 ± 399.7 vs. 163 ± 264.3 pg/ml, p=0.04. Conclusion Arrhythmias and conduction disorders are common in patients with scleroderma. Patients with such disorders are older, have a higher prevalence of pulmonary hypertension, more severe mitral and tricuspid regurgitation, left atrial and right ventricular dilation on echocardiography. PMID:27115105

  16. Abnormal heart rate turbulence predicts the initiation of ventricular arrhythmias

    OpenAIRE

    Iwasa, Atsushi; Hwa, Michael; Hassankhani, Alborz; Liu, Taylor; Narayan, Sanjiv M.

    2005-01-01

    Background: Abnormal heart rate turbulence (HRT) reflects autonomic derangements predicting all-cause mortality, yet has riot been shown to predict ventriculor arrhythmias in at-risk patients. We hypothesized that HRT at programmed ventricular stimulation (PVS) would predict arrhythmia initiation in patients with left ventriculor dysfunction. Methods: We studied 27 patients with coronary disease, left ventricular ejection fraction (LVEF) 26.7 +/- 9.1%, and plasma B-type natriuretic peptide (B...

  17. Arrhythmias and electrocardiographic changes in systolic heart failure

    OpenAIRE

    Ashok Devkota; Ahmed Bakhit; Alix Dufresne; Aung Naing Oo; Premraj Parajuli; Saveena Manhas

    2016-01-01

    Background: Heart failure is a common condition that that leads to hospitalization. It is associated with various atrial and ventricular arrhythmias. Aim: The aim of this study is to find common arrhythmias and electrocardiographic changes in hospitalized patients who have systolic heart failure. Materials and Methods: This is a retrospective study of medical records, and electrocardiograms (EKGs) of 157 patients admitted to our hospital who had systolic heart failure with ejection fraction (...

  18. Computer-assisted education system for arrhythmia (CAESAR).

    Science.gov (United States)

    Fukushima, M; Inoue, M; Fukunami, M; Ishikawa, K; Inada, H; Abe, H

    1984-08-01

    A computer-assisted education system for arrhythmia (CAESAR) was developed for students to acquire the ability to logically diagnose complicated arrhythmias. This system has a logical simulator of cardiac rhythm using a mathematical model of the impulse formation and conduction system of the heart. A simulated arrhythmia (ECG pattern) is given on a graphic display unit with simulated series of the action potential of five pacemaker centers and the "ladder diagram" of impulse formation and conduction, which show the mechanism of that arrhythmia. For the purpose of the evaluation of this system, 13 medical students were given two types of tests concerning arrhythmias before and after 2-hr learning with this system. The scores they obtained after learning increased significantly from 73.3 +/- 11.9 to 93.2 +/- 3.0 (P less than 0.001) in one test and from 47.2 +/- 17.9 to 64.9 +/- 19.6 (P less than 0.001) in another one. These results proved that this CAI system is useful and effective for training ECG interpretation of arrhythmias.

  19. New-onset atrial fibrillation predicts malignant arrhythmias in post-myocardial infarction patients - A Cardiac Arrhythmias and RIsk Stratification after acute Myocardial infarction (CARISMA) substudy

    DEFF Research Database (Denmark)

    Ruwald, Anne Christine Huth; Bloch Thomsen, Poul Erik; Gang, Uffe Jakob Ortved;

    2013-01-01

    After myocardial infarction (MI) the risk of sudden cardiac death due to arrhythmias is substantial.......After myocardial infarction (MI) the risk of sudden cardiac death due to arrhythmias is substantial....

  20. Fractal ventilation enhances respiratory sinus arrhythmia

    Directory of Open Access Journals (Sweden)

    Girling Linda G

    2005-05-01

    Full Text Available Abstract Background Programming a mechanical ventilator with a biologically variable or fractal breathing pattern (an example of 1/f noise improves gas exchange and respiratory mechanics. Here we show that fractal ventilation increases respiratory sinus arrhythmia (RSA – a mechanism known to improve ventilation/perfusion matching. Methods Pigs were anaesthetised with propofol/ketamine, paralysed with doxacurium, and ventilated in either control mode (CV or in fractal mode (FV at baseline and then following infusion of oleic acid to result in lung injury. Results Mean RSA and mean positive RSA were nearly double with FV, both at baseline and following oleic acid. At baseline, mean RSA = 18.6 msec with CV and 36.8 msec with FV (n = 10; p = 0.043; post oleic acid, mean RSA = 11.1 msec with CV and 21.8 msec with FV (n = 9, p = 0.028; at baseline, mean positive RSA = 20.8 msec with CV and 38.1 msec with FV (p = 0.047; post oleic acid, mean positive RSA = 13.2 msec with CV and 24.4 msec with FV (p = 0.026. Heart rate variability was also greater with FV. At baseline the coefficient of variation for heart rate was 2.2% during CV and 4.0% during FV. Following oleic acid the variation was 2.1 vs. 5.6% respectively. Conclusion These findings suggest FV enhances physiological entrainment between respiratory, brain stem and cardiac nonlinear oscillators, further supporting the concept that RSA itself reflects cardiorespiratory interaction. In addition, these results provide another mechanism whereby FV may be superior to conventional CV.

  1. Cardiac Arrhythmias in a Septic ICU Population: A Review

    Directory of Open Access Journals (Sweden)

    Schwartz Andrei

    2015-10-01

    Full Text Available Progressive cardiovascular deterioration plays a central role in the pathogenesis of multiple organ failure (MOF caused by sepsis. Evidence of various cardiac arrhythmias in septic patients has been reported in many published studies. In the critically ill septic patients, compared to non-septic patients, new onset atrial fibrillation episodes are associated with high mortality rates and poor outcomes, amongst others being new episodes of stroke, heart failure and long vasopressor usage. The potential mechanisms of the development of new cardiac arrhythmias in sepsis are complex and poorly understood. Cardiac arrhythmias in critically ill septic patients are most likely to be an indicator of the severity of pre-existing critical illness.

  2. Nonlinear interpolation fractal classifier for multiple cardiac arrhythmias recognition

    Energy Technology Data Exchange (ETDEWEB)

    Lin, C.-H. [Department of Electrical Engineering, Kao-Yuan University, No. 1821, Jhongshan Rd., Lujhu Township, Kaohsiung County 821, Taiwan (China); Institute of Biomedical Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China)], E-mail: eechl53@cc.kyu.edu.tw; Du, Y.-C.; Chen Tainsong [Institute of Biomedical Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China)

    2009-11-30

    This paper proposes a method for cardiac arrhythmias recognition using the nonlinear interpolation fractal classifier. A typical electrocardiogram (ECG) consists of P-wave, QRS-complexes, and T-wave. Iterated function system (IFS) uses the nonlinear interpolation in the map and uses similarity maps to construct various data sequences including the fractal patterns of supraventricular ectopic beat, bundle branch ectopic beat, and ventricular ectopic beat. Grey relational analysis (GRA) is proposed to recognize normal heartbeat and cardiac arrhythmias. The nonlinear interpolation terms produce family functions with fractal dimension (FD), the so-called nonlinear interpolation function (NIF), and make fractal patterns more distinguishing between normal and ill subjects. The proposed QRS classifier is tested using the Massachusetts Institute of Technology-Beth Israel Hospital (MIT-BIH) arrhythmia database. Compared with other methods, the proposed hybrid methods demonstrate greater efficiency and higher accuracy in recognizing ECG signals.

  3. Ion channelopathy and hyperphosphorylation contributing to cardiac arrhythmias

    Institute of Scientific and Technical Information of China (English)

    De-zai DAI; Feng YU

    2005-01-01

    The occurrence of cardiac arrhythmias is related to the abnormality of ion channels not only in sarcolemma but also in the sarcoplasmic reticulum, which regulates the process of calcium release and up-take intracellularly. Patterns of ion channelopathy in the sarcolemma can be divided into single channel disorder from gene mutations and multiple channels disorder in a diseased hypertrophied heart. Abnormal RyR2, FKBP12.6, SERCA2a, and PLB are also involved in the initiation of cardiac arrhythmias. Maladjustment by hyperphosphorylation on the ion channels in the sarcolemma and RyR2-FKBP12.6 and SERCA2a-PLB is discussed. Hyperphosphorylation, which is the main abnormality upstream to ion channels, can be targeted for suppressing the deterioration of ion channelopathy in terms of new drug discovery in the treatment and prevention of malignant cardiac arrhythmias.

  4. Electrocardiographic abnormalities and cardiac arrhythmias in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Goudis, Christos A; Konstantinidis, Athanasios K; Ntalas, Ioannis V; Korantzopoulos, Panagiotis

    2015-11-15

    Chronic obstructive pulmonary disease (COPD) is independently associated with an increased burden of cardiovascular disease. Besides coronary artery disease (CAD) and congestive heart failure (CHF), specific electrocardiographic (ECG) abnormalities and cardiac arrhythmias seem to have a significant impact on cardiovascular prognosis of COPD patients. Disturbances of heart rhythm include premature atrial contractions (PACs), premature ventricular contractions (PVCs), atrial fibrillation (AF), atrial flutter (AFL), multifocal atrial tachycardia (MAT), and ventricular tachycardia (VT). Of note, the identification of ECG abnormalities and the evaluation of the arrhythmic risk may have significant implications in the management and outcome of patients with COPD. This article provides a concise overview of the available data regarding ECG abnormalities and arrhythmias in these patients, including an elaborated description of the underlying arrhythmogenic mechanisms. The clinical impact and prognostic significance of ECG abnormalities and arrhythmias in COPD as well as the appropriate antiarrhythmic therapy and interventions in this setting are also discussed. PMID:26218181

  5. Laboratory Markers of Ventricular Arrhythmia Risk in Renal Failure

    Directory of Open Access Journals (Sweden)

    Ioana Mozos

    2014-01-01

    Full Text Available Sudden cardiac death continues to be a major public health problem. Ventricular arrhythmia is a main cause of sudden cardiac death. The present review addresses the links between renal function tests, several laboratory markers, and ventricular arrhythmia risk in patients with renal disease, undergoing or not hemodialysis or renal transplant, focusing on recent clinical studies. Therapy of hypokalemia, hypocalcemia, and hypomagnesemia should be an emergency and performed simultaneously under electrocardiographic monitoring in patients with renal failure. Serum phosphates and iron, PTH level, renal function, hemoglobin and hematocrit, pH, inflammatory markers, proteinuria and microalbuminuria, and osmolarity should be monitored, besides standard 12-lead ECG, in order to prevent ventricular arrhythmia and sudden cardiac death.

  6. PERFORMANCE ANALYSIS OF SOFT COMPUTING TECHNIQUES FOR CLASSIFYING CARDIAC ARRHYTHMIA

    Directory of Open Access Journals (Sweden)

    R GANESH KUMAR

    2014-01-01

    Full Text Available Cardiovascular diseases kill more people than other diseases. Arrhythmia is a common term used for cardiac rhythm deviating from normal sinus rhythm. Many heart diseases are detected through electrocardiograms (ECG analysis. Manual analysis of ECG is time consuming and error prone. Thus, an automated system for detecting arrhythmia in ECG signals gains importance. Features are extracted from time series ECG data with Discrete Cosine Transform (DCT computing the distance between RR waves. The feature is the beat’s extracted RR interval. Frequency domain extracted features are classified using Classification and Regression Tree (CART, Radial Basis Function (RBF, Support Vector Machine (SVM and Multilayer Perceptron Neural Network (MLP-NN. Experiments were conducted on the MIT-BIH arrhythmia database.

  7. Circadian arrhythmia dysregulates emotional behaviors in aged Siberian hamsters.

    Science.gov (United States)

    Prendergast, Brian J; Onishi, Kenneth G; Patel, Priyesh N; Stevenson, Tyler J

    2014-03-15

    Emotional behaviors are influenced by the circadian timing system. Circadian disruptions are associated with depressive-like symptoms in clinical and preclinical populations. Circadian rhythm robustness declines markedly with aging and may contribute to susceptibility to emotional dysregulation in aged individuals. The present experiments used a model of chronic circadian arrhythmia generated noninvasively, via a series of circadian-disruptive light treatments, to investigate interactions between circadian desynchrony and aging on depressive- and anxiety-like behaviors, and on limbic neuroinflammatory gene expression that has been linked with emotionality. We also examined whether a social manipulation (group housing) would attenuate effects of arrhythmia on emotionality. In aged (14-18 months of age) male Siberian hamsters, circadian arrhythmia increased behavioral despair and decreased social motivation, but decreased exploratory anxiety. These effects were not evident in younger (5-9 months of age) hamsters. Social housing (3-5 hamsters/cage) abolished the effects of circadian arrhythmia on emotionality. Circadian arrhythmia alone was without effect on hippocampal or cortical interleukin-1β (IL-1β) and indoleamine 2,3-dioxygenase (Ido) mRNA expression in aged hamsters, but social housing decreased hippocampal IL-1β and Ido mRNAs. The data demonstrate that circadian disruption can negatively impact affective state, and that this effect is pronounced in older individuals. Although clear associations between circadian arrhythmia and constitutive limbic proinflammatory activity were not evident, the present data suggest that social housing markedly inhibits constitutive hippocampal IL-1β and Ido activity, which may contribute to the ameliorating effects of social housing on a number of emotional behaviors.

  8. QTc-prolonging drugs and hospitalizations for cardiac arrhythmias

    DEFF Research Database (Denmark)

    De Bruin, Marie L; Hoes, Arno W; Leufkens, Hubert G M

    2003-01-01

    -prolonging drugs. A statistically nonsignificant increased risk for arrhythmias (OR 1.2, 95% CI 0.8 to 1.9) was observed in patients who received QTc-prolonging drugs. A clearly increased risk of arrhythmias was, however, found in patients with a history of asthma (OR 9.9, 95% CI 1.0 to 100) and in patients using...... with a history of asthma and patients taking potassium-lowering drugs. The use of QTc-prolonging drugs should therefore be either avoided or monitored closely in these specific patients....

  9. Poincare Geometry-Characterized Arrhythmia Identification Scheme in Grid

    Directory of Open Access Journals (Sweden)

    Dong-Hyun Kim

    2009-12-01

    Full Text Available In this paper, we propose a new scheme of Poincare geometry-characterized ECG analysis for cardiac disease identification. Based on reliable P-wave detection we created P-P Poincare plot applying P-P intervals of ECG signal. By the new geometric Poincare plot analysis, which combines R-R intervals and P-P intervals, weidentified geometric differences of normal and arrhythmia ECG databases at PhysioBank in Physionet. Poincare descriptors show that the analysis scheme can classify two ECG signals reliably. Furthermore, we discuss a cardiac disease estimation system that may be applicable to estimate the occurrence of arrhythmia in healthy person.

  10. An Unusual Cause of Cardiac Arrhythmias; Mediastinal Schwannoma

    Directory of Open Access Journals (Sweden)

    Serdar Ozkan

    2014-02-01

    Full Text Available Schwannomas are rare tumours, which originated from neural crest cells. Thoracic schwannomas are very rare and most commonly seen in posterior mediastinum. In a 39 year old female patient whose tumor story dated back to 4 years, a 14 cm extra parenchymal intrathoracic tumor was observed to put minimal pressure on the heart. The patient%u2019s arrhythmia, who had preoperative complaints of palpitations, was improved after tumor excision. Although schwannomas generally are asympthomatic masses, they can lead mass effect according to their localization. In this study, patient with thoracic schwannoma presented with cardiac arrhythmia which never reported in literature so far.

  11. 78 FR 36787 - Rechanneling the Current Cardiac Risk Paradigm: Arrhythmia Risk Assessment During Drug...

    Science.gov (United States)

    2013-06-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Rechanneling the Current Cardiac Risk Paradigm: Arrhythmia... the Current Cardiac Risk Paradigm: Arrhythmia Risk Assessment During Drug Development Without...

  12. Comparison of Arrhythmias among Different Left Ventricular Geometric Patterns in Essential Hypertension

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The differences of arrhythmias among distinct left ventricular geometric patterns in the patients with essential hypertension were studied. 179 patients with essential hypertension received 24 h dynamic ECG recording, ambulatory blood pressure monitoring, echocardiography examination, etc. According to the examinations, left ventricular geometric patterns and arrhythmias were identified. The comparison of morbidity of arrhythmias between the left ventricular remodeling group and the normal geometric pattern group was performed. The multiple stepwise regression analysis was carried out to identify the independent determinants of arrhythmias. After these predictors were controlled or adjusted, the severity of arrhythmias among different left ventricular geometric patterns was compared. It was found that the morbidity of atrial arrhythmia, ventricular arrhythmia and complex ventricular arrhythmias in the left ventricular remodeling group was significantly higher than in the normal geometric pattern group respectively. There were many independent factors influencing on arrhythmias in essential hypertension. Of all these factors, some indices of left ventricular anatomic structure, grade of hypertension, left atrial inner dimension, E/A, diastolic blood pressure load value at night and day average heart rate and so on were very important. After the above-mentioned factors were adjusted, the differences of the orders of arrhythmias between partial geometric patterns were reserved, which resulted from the differences of the geometric patterns. Many factors contributed to arrhythmias of essential hypertension, such as grade of hypertension, LVMI, LA, PWT and so on. The severity of arrhythmias was different in different left ventricular geometric patterns.

  13. 21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to...

  14. Electrocardiographic abnormalities and cardiac arrhythmias in structural brain lesions.

    Science.gov (United States)

    Katsanos, Aristeidis H; Korantzopoulos, Panagiotis; Tsivgoulis, Georgios; Kyritsis, Athanassios P; Kosmidou, Maria; Giannopoulos, Sotirios

    2013-07-31

    Cardiac arrhythmias and electrocardiographic abnormalities are frequently observed after acute cerebrovascular events. The precise mechanism that leads to the development of these arrhythmias is still uncertain, though increasing evidence suggests that it is mainly due to autonomic nervous system dysregulation. In massive brain lesions sympathetic predominance and parasympathetic withdrawal during the first 72 h are associated with the occurrence of severe secondary complications in the first week. Right insular cortex lesions are also related with sympathetic overactivation and with a higher incidence of electrocardiographic abnormalities, mostly QT prolongation, in patients with ischemic stroke. Additionally, female sex and hypokalemia are independent risk factors for severe prolongation of the QT interval which subsequently results in malignant arrhythmias and poor outcome. The prognostic value of repolarization changes commonly seen after aneurysmal subarachnoid hemorrhage, such as ST segment, T wave, and U wave abnormalities, still remains controversial. In patients with traumatic brain injury both intracranial hypertension and cerebral hypoperfusion correlate with low heart rate variability and increased mortality. Given that there are no firm guidelines for the prevention or treatment of the arrhythmias that appear after cerebral incidents this review aims to highlight important issues on this topic. Selected patients with the aforementioned risk factors could benefit from electrocardiographic monitoring, reassessment of the medications that prolong QTc interval, and administration of antiadrenergic agents. Further research is required in order to validate these assumptions and to establish specific therapeutic strategies.

  15. Cardiac arrhythmias in adults with congenital heart disease

    NARCIS (Netherlands)

    Z. Koyak

    2016-01-01

    Arrhythmias are a major cause of hospital admissions and morbidity in adults with congenital heart disease (CHD). Furthermore, the leading cause of death in adults with CHD is sudden cardiac death (SCD) of presumed arrhythmic aetiology. The main objectives of this thesis were to identify risk factor

  16. Dofetilide: a new drug to control cardiac arrhythmia

    DEFF Research Database (Denmark)

    Elming, Hanne; Brendorp, Bente; Pedersen, Ole Dyg;

    2003-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. Mortality, and especially morbidity caused by AF, are major and growing health problems in the western world. AF is strongly associated with arterial hypertension, congestive heart failure, valvular heart disease, ischaemic heart...

  17. Is it Safe? Adverse drug effects and cardiac arrhythmias

    NARCIS (Netherlands)

    Varkevisser, R.

    2014-01-01

    The potentially life-threatening polymorphic ventricular arrhythmia Torsade de Pointes (TdP) generally occurs in the setting of delayed ventricular repolarization, as reflected on the ECG by a prolonged QT interval. A growing number of drugs are associated with QT prolongation and/or TdP, as a resul

  18. Mortality of Inherited Arrhythmia Syndromes Insight Into Their Natural History

    NARCIS (Netherlands)

    Nannenberg, Eline A.; Sijbrands, Eric J. G.; Dijksman, Lea M.; Alders, Marielle; van Tintelen, J. Peter; Birnie, Martijn; van Langen, Irene M.; Wilde, Arthur A. M.

    2012-01-01

    Background-For most arrhythmia syndromes, the risk of sudden cardiac death for asymptomatic mutation carriers is ill defined. Data on the natural history of these diseases, therefore, are essential. The family tree mortality ratio method offers the unique possibility to study the natural history at

  19. Cardiac arrhythmias and left ventricular hypertrophy in systemic hypertension

    International Nuclear Information System (INIS)

    Background: Hypertensive left ventricular hypertrophy (LVH) is associated with increased risk of arrhythmias and mortality. Objective was to investigate the prevalence of cardiac arrhythmias and LVH in systemic hypertension. Methods: In all subjects blood pressure was measured, electrocardiography and echocardiography was done. Holter monitoring and exercise test perform in certain cases. There were 500 hypertensive patients, 156 (31.2%) men and 344 (69%) women >30 years of age in the study. Among them 177 (35.4%) were diabetic, 224 (45%) were dyslipidemia, 188 (37.6%) were smokers, and 14 (3%) had homocysteinemia. Mean systolic BP (SBP) was 180 +- 20 mm Hg and diastolic BP (DBP) was 95 +- 12 in male and female patients. Left ventricular mass index (LVMI) was 119.2 +- 30 2 2gm/m in male while 103 +- 22 gm/m in female patients. Palpitation was seen in 126 (25%) male and 299 (59.8%) female patients. Atrial fibrillation was noted in 108 (21.6%) male and 125 (25%) female patients, 30 (6%) male and 82 (16.4%) female patients had atrial flutter. Ventricular tachycardia was noted in 37 (7.4%) male and 59 (11.8%) female patients. Holter monitoring showed significant premature ventricular contractions (PVC'S) in 109 (21.8%) male and 128 (25.69%) female patients while Holter showed atrial arrhythmias (APC'S) in 89 (17.8%) males and 119 (23.8%) females. Angiography findings diagnosed coronary artery disease in 119 (23.8%) with CAD male and 225 (45%) without CAD while 47 (9.4%) females presented with CAD and 109 (21.8%) without CAD. Conclusion: A significant association has been demonstrated between hypertension and arrhythmias. Diastolic dysfunction of the left ventricle, left atrial size and function, as well as LVH have been suggested as the underlying risk factors for supraventricular, ventricular arrhythmias and sudden death in hypertensives with LVH. (author)

  20. Atrial Arrhythmias in Astronauts - Summary of a NASA Summit

    Science.gov (United States)

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

    2010-01-01

    Background and Problem Definition: To evaluate NASA s current standards and practices related to atrial arrhythmias in astronauts, Space Medicine s Advanced Projects Section at the Johnson Space Center was tasked with organizing a summit to discuss the approach to atrial arrhythmias in the astronaut cohort. Since 1959, 11 cases of atrial fibrillation, atrial flutter, or supraventricular tachycardia have been recorded among active corps crewmembers. Most of the cases were paroxysmal, although a few were sustained. While most of the affected crewmembers were asymptomatic, those slated for long-duration space flight underwent radiofrequency ablation treatment to prevent further episodes of the arrhythmia. The summit was convened to solicit expert opinion on screening, diagnosis, and treatment options, to identify gaps in knowledge, and to propose relevant research initiatives. Summit Meeting Objectives: The Atrial Arrhythmia Summit brought together a panel of six cardiologists, including nationally and internationally renowned leaders in cardiac electrophysiology, exercise physiology, and space flight cardiovascular physiology. The primary objectives of the summit discussions were to evaluate cases of atrial arrhythmia in the astronaut population, to understand the factors that may predispose an individual to this condition, to understand NASA s current capabilities for screening, diagnosis, and treatment, to discuss the risks associated with treatment of crewmembers assigned to long-duration missions or extravehicular activities, and to discuss recommendations for prevention or management of future cases. Summary of Recommendations: The summit panel s recommendations were grouped into seven categories: Epidemiology, Screening, Standards and Selection, Treatment of Atrial Fibrillation Manifesting Preflight, Atrial Fibrillation during Flight, Prevention of Atrial Fibrillation, and Future Research

  1. Arrhythmias and electrocardiographic changes in systolic heart failure

    Directory of Open Access Journals (Sweden)

    Ashok Devkota

    2016-01-01

    Full Text Available Background: Heart failure is a common condition that that leads to hospitalization. It is associated with various atrial and ventricular arrhythmias. Aim: The aim of this study is to find common arrhythmias and electrocardiographic changes in hospitalized patients who have systolic heart failure. Materials and Methods: This is a retrospective study of medical records, and electrocardiograms (EKGs of 157 patients admitted to our hospital who had systolic heart failure with ejection fraction (EF 35%. Twelve-lead EKG of these patients was studied to identify common arrhythmia and demographic variables; laboratory results were compared to identify the differences. Results: A total of 157 patients with systolic heart failure, 63.7% had an EF ≤ 35%. Hypertension 82.8%, diabetes 49%, coronary artery disease 40.8%, chronic obstructive pulmonary disease or bronchial asthma 22.3%, and stroke 12.1% were common associated co-morbidities. On analysis of EKG, 28.6% had tachycardia, 21.9% had prolonged PR > 200 ms, 16.3% had wide QRS > 120 ms, 70.7% had prolonged corrected QT (QTc, and 42.2% had left axis deviation. The most common arrhythmias were sinus tachycardia and atrial fibrillation/flutter which were found in 14.6% and 13.4%, respectively. The left ventricular hypertrophy was a common abnormality found in 22.4% followed by ventricular premature contractions 18.4%, atrial premature contractions 9.5%, and left bundle branch block 6.1%. Patients with severe systolic heart failure had prolonged QRS (P = 0.02 and prolonged QTc (P = 0.01 as compared to the other group. Conclusions: Sinus tachycardia and atrial fibrillation/flutter were common arrhythmias in patients with systolic heart failure. Patients with severe systolic heart failure had statistically significant prolongation of the QRS duration and QTc interval.

  2. Effect of Encoding Method on the Distribution of Cardiac Arrhythmias

    CERN Document Server

    Mora, Luis A

    2011-01-01

    This paper presents the evaluation of the effect of the method of ECG signal encoding, based on nonlinear characteristics such as information entropy and Lempel-Ziv complexity, on the distribution of cardiac arrhythmias. Initially proposed a procedure electrocardiographic gating to compensate for errors inherent in the process of filtering segments. For the evaluation of distributions and determine which of the different encoding methods produces greater separation between different kinds of arrhythmias studied (AFIB, AFL, SVTA, VT, Normal's), use a function based on the dispersion of the elements on the centroid of its class, the result being that the best encoding for the entire system is through the method of threshold value for a ternary code with E = 1 / 12.

  3. Classification enhancible grey relational analysis for cardiac arrhythmias discrimination.

    Science.gov (United States)

    Lin, Chia-Hung

    2006-04-01

    This paper proposes a method for electrocardiogram (ECG) heartbeat recognition using classification enhancible grey relational analysis (GRA). The ECG beat recognition can be divided into a sequence of stages, starting with feature extraction and then according to characteristics to identify the cardiac arrhythmias including the supraventricular ectopic beat, bundle branch ectopic beat, and ventricular ectopic beat. Gaussian wavelets are used to enhance the features from each heartbeat, and GRA performs the recognition tasks. With the MIT-BIH arrhythmia database, the experimental results demonstrate the efficiency of the proposed non-invasive method. Compared with artificial neural network, the test results also show high accuracy, good adaptability, and faster processing time for the detection of heartbeat signals. PMID:16937172

  4. Multiple cardiac arrhythmia recognition using adaptive wavelet network.

    Science.gov (United States)

    Lin, Chia-Hung; Chen, Pei-Jarn; Chen, Yung-Fu; Lee, You-Yun; Chen, Tainsong

    2005-01-01

    This paper proposes a method for electrocardiogram (ECG) heartbeat pattern recognition using adaptive wavelet network (AWN). The ECG beat recognition can be divided into a sequence of stages, starting from feature extraction and conversion of QRS complexes, and then identifying cardiac arrhythmias based on the detected features. The discrimination method of ECG beats is a two-subnetwork architecture, consisting of a wavelet layer and a probabilistic neural network (PNN). Morlet wavelets are used to extract the features from each heartbeat, and then PNN is used to analyze the meaningful features and perform discrimination tasks. The AWN is suitable for application in a dynamic environment, with add-in and delete-off features using automatic target adjustment and parameter tuning. The experimental results obtained by testing the data of the MIT-BIH arrhythmia database demonstrate the efficiency of the proposed method. PMID:17281539

  5. 320-detector row CT coronary angiography in patients with arrhythmia

    International Nuclear Information System (INIS)

    Objective: To evaluate the feasibility of CT coronary angiography (CTCA) in patients with arrhythmia using 320-detector row CT. Methods: Thirty-one patients with persistent atrial fibrillation and 8 patients with premature ventricular contraction were enrolled in this study. All patients underwent 320- detector row CTCA. CT image quality was evaluated with 4-point grading scale by two radiologists. Inter- observer agreement was evaluated by Kappa statistics. The radiation dose was calculated. Results: In total 510 coronary segments, 496 (97.2%) segments met diagnostic standard. The mean effective dose was (12.7±4.8) mSv in this study. There was a good agreement in image quality scoring between the two reviewers (Kappa = 0.72). Conclusion: 320-detector row CTCA is feasible in patients with atrial fibrillation and premature ventricular contraction. Arrhythmia may not be considered as a contraindication to CTCA. (authors)

  6. Optical mapping system for visualizing arrhythmias in isolated mouse atria.

    Science.gov (United States)

    Schmidt, Robyn; Nygren, Anders

    2006-01-01

    Optical mapping has become an important technique in the study of cardiac electrophysiology, especially in terms of investigating the mechanisms of cardiac arrhythmias. The increasing availability of transgenic mice as models for cardiovascular disease is driving the need for instrumentation suitable for the study of electrical activity in the mouse heart. In this paper we evaluate our optical mapping system's ability to clearly record induced arrhythmic activity in an isolated mouse atrial preparation. Preliminary results indicate that the signal quality is high enough that individual optically recorded action potentials can be discerned in many pixels, even without post-processing for noise removal. The optical mapping video is clear enough for general observations regarding the patterns of electrical propagation during arrhythmic behaviour. The induced arrhythmias appear to have a regular pattern of activity, and are likely best classified as atrial tachycardias.

  7. ECG Signal Analysis and Arrhythmia Detection using Wavelet Transform

    Science.gov (United States)

    Kaur, Inderbir; Rajni, Rajni; Marwaha, Anupma

    2016-06-01

    Electrocardiogram (ECG) is used to record the electrical activity of the heart. The ECG signal being non-stationary in nature, makes the analysis and interpretation of the signal very difficult. Hence accurate analysis of ECG signal with a powerful tool like discrete wavelet transform (DWT) becomes imperative. In this paper, ECG signal is denoised to remove the artifacts and analyzed using Wavelet Transform to detect the QRS complex and arrhythmia. This work is implemented in MATLAB software for MIT/BIH Arrhythmia database and yields the sensitivity of 99.85 %, positive predictivity of 99.92 % and detection error rate of 0.221 % with wavelet transform. It is also inferred that DWT outperforms principle component analysis technique in detection of ECG signal.

  8. Preoperative Arrhythmias Such as Atrial Fibrillation: Cardiovascular Surgery Risk Factor

    OpenAIRE

    Diana Anghel; Radu Anghel; Flavia Corciova; Mihail Enache; Grigore Tinica

    2014-01-01

    Atrial fibrillation is still the most common arrhythmia that occurs in heart surgery. However, there is few literature data on the manner in which preoperative atrial fibrillation may influence the postoperative outcome of various heart surgery procedures. The purpose of our research is to assess the effects of preoperative atrial fibrillation on patients having undergone different heart surgery procedures. The results of our research are a review of clinical data which were collected prospec...

  9. Developmental trajectories of respiratory sinus arrhythmia: Associations with social responsiveness

    OpenAIRE

    Patriquin, Michelle A.; Lorenzi, Jill; Scarpa, Angela; Bell, Martha Ann

    2013-01-01

    The present longitudinal study examined relations between respiratory sinus arrhythmia (RSA) development and social responsiveness characteristics associated with autism spectrum disorders. Group-based developmental trajectory modeling was used to characterize RSA development patterns in 106 typically developing children across 5, 10, 24, 36, and 48 months of age. A two-group model fit of RSA development was found: a “typically” and “atypically” developing group. The typical group gradually i...

  10. Cardiac arrhythmia and heart failure: From bench to bedside

    Institute of Scientific and Technical Information of China (English)

    Yong-Fu Xiao

    2011-01-01

    @@ Cardiac arrhythmia is an abnormal rate and/or rhythm of a heart due to its abnormal electrical impulse origination and/or propagation.Various etiologies can cause arrhythnuas.Heart failure(HF)is a clinical syndrome due to an impaired heart that can not pump sufficient blood to meet the systemic metabolic needs.The common causes of HF include myocardial infarction,hypertension,valvular heart disease,and cardiomyopathy.

  11. Methodological Issues in the Quantification of Respiratory Sinus Arrhythmia

    OpenAIRE

    Denver, John W.; Reed, Shawn F.; Porges, Stephen W.

    2006-01-01

    Although respiratory sinus arrhythmia (RSA) is a commonly quantified physiological variable, the methods for quantification are not consistent. This manuscript questions the assumption that respiration frequency needs to be manipulated or monitored to generate an accurate measure of RSA amplitude. A review of recent papers is presented that contrast RSA amplitude with measures that use respiratory parameters to adjust RSA amplitude. In addition, data from two studies are presented to evaluate...

  12. Treatment of depression in an adolescent with cardiomyopathy and arrhythmia.

    Science.gov (United States)

    Tanidir, Canan; Tanidir, Ibrahim C; Tuzcu, Volkan

    2015-10-01

    Patients with cardiomyopathy have a higher incidence of mood and anxiety disorders, resulting in greater probability for hospitalisation and increased risk for arrhythmia and death. We report a case of a 16-year-old boy with Danon disease, Wolff-Parkinson-White syndrome, and hypertrophic cardiomyopathy, who later developed depression and significant weight loss. The patient was successfully treated for his anxiety and depression with mirtazapine without any adverse cardiac effects. PMID:25400066

  13. Noninvasive Cardiac Screening in Young Athletes With Ventricular Arrhythmias

    OpenAIRE

    Steriotis, Alexandros Klavdios; Nava, Andrea; Rigato, Ilaria; Mazzotti, Elisa; Daliento, Luciano; Thiene, Gaetano; Basso, Cristina; Corrado, Domenico; Bauce, Barbara

    2013-01-01

    The aim of this study was to analyze using noninvasive cardiac examinations a series of young athletes discovered to have ventricular arrhythmias (VAs) during the preparticipation screening program for competitive sports. One hundred forty-five athletes (mean age 17 ± 5 years) were evaluated. The study protocol included electrocardiography (ECG), exercise testing, 2-dimensional and Doppler echocardiography, 24-hour Holter monitoring, signal-averaged ECG, and in selected cases contrast-enhance...

  14. Is it Safe? Adverse drug effects and cardiac arrhythmias

    OpenAIRE

    Varkevisser, R.

    2014-01-01

    The potentially life-threatening polymorphic ventricular arrhythmia Torsade de Pointes (TdP) generally occurs in the setting of delayed ventricular repolarization, as reflected on the ECG by a prolonged QT interval. A growing number of drugs are associated with QT prolongation and/or TdP, as a result, development of promising new drugs has been aborted, and already marketed drugs have received severe restrictions or have been withdrawn. To address this cardiac safety issue, international guid...

  15. Exploiting periodicity to extract the atrial activity in atrial arrhythmias

    OpenAIRE

    Llinares Llopis, Raúl; Igual García, Jorge

    2011-01-01

    [EN] Atrial fibrillation disorders are one of the main arrhythmias of the elderly. The atrial and ventricular activities are decoupled during an atrial fibrillation episode, and very rapid and irregular waves replace the usual atrial P-wave in a normal sinus rhythm electrocardiogram (ECG). The estimation of these wavelets is a must for clinical analysis. We propose a new approach to this problem focused on the quasiperiodicity of these wavelets. Atrial activity is characterized by...

  16. Artifact versus arrhythmia in pseudo-polymorphic tachycardia; case report

    OpenAIRE

    Ahmed V; Patel A; Sharma A; Bloomfield D

    2015-01-01

    Vaseem Ahmed, Anish Patel, Abhishek Sharma, Dennis Bloomfield Department of Medicine, Richmond University Medical Center, Staten Island, NY, USA Abstract: We present the case of a young male patient in sinus rhythm whose electrocardiogram (ECG) was initially misinterpreted as ventricular tachycardia. Electrocardiographic artifact appearing to be ventricular tachycardia commonly occurs and ECG criteria have been described to aid in the discrimination between artifact and true arrhythmia. Ther...

  17. Life-threatening ventricular arrhythmia recognition by nonlinear descriptor

    OpenAIRE

    Krishnan Shankar; Chan Kap; Sun Yan

    2005-01-01

    Abstract Background Ventricular tachycardia (VT) and ventricular fibrillation (VF) are ventricular cardiac arrhythmia that could be catastrophic and life threatening. Correct and timely detection of VT or VF can save lives. Methods In this paper, a multiscale-based non-linear descriptor, the Hurst index, is proposed to characterize the ECG episode, so that VT and VF can be recognized as different from normal sinus rhythm (NSR) in the descriptor domain. Results This newly proposed technique wa...

  18. Arrhythmia as a cardiac manifestation in MELAS syndrome

    Directory of Open Access Journals (Sweden)

    Tamara Thomas

    2015-09-01

    Full Text Available A 44-year-old female with a diagnosis of mitochondrial myopathy, encephalopathy and stroke-like episodes (MELAS syndrome had progressive left ventricular hypertrophy (LVH on echocardiogram. A Holter monitor demonstrated episodes of non-sustained atrial tachycardia, a finding not been previously described in this population. This unique case of MELAS syndrome demonstrates the known associated cardiac manifestation of LVH and the new finding of atrial tachycardia which may represent the potential for subclinical arrhythmia in this population.

  19. Arrhythmia as a cardiac manifestation in MELAS syndrome.

    Science.gov (United States)

    Thomas, Tamara; Craigen, William J; Moore, Ryan; Czosek, Richard; Jefferies, John L

    2015-09-01

    A 44-year-old female with a diagnosis of mitochondrial myopathy, encephalopathy and stroke-like episodes (MELAS) syndrome had progressive left ventricular hypertrophy (LVH) on echocardiogram. A Holter monitor demonstrated episodes of non-sustained atrial tachycardia, a finding not been previously described in this population. This unique case of MELAS syndrome demonstrates the known associated cardiac manifestation of LVH and the new finding of atrial tachycardia which may represent the potential for subclinical arrhythmia in this population.

  20. Cardiac arrhythmia classification using multi-modal signal analysis.

    Science.gov (United States)

    Kalidas, V; Tamil, L S

    2016-08-01

    In this paper, as a contribution to the Physionet/Computing in Cardiology 2015 Challenge, we present individual algorithms to accurately classify five different life threatening arrhythmias with the goal of suppressing false alarm generation in intensive care units. Information obtained by analysing electrocardiogram, photoplethysmogram and arterial blood pressure signals was utilized to develop the classification models. Prior to classification, the signals were subject to a signal pre-processing stage for quality analysis. Classification was performed using a combination of support vector machine based machine learning approach and logical analysis techniques. The predicted result for a certain arrhythmia classification model was verified by logical analysis to aid in reduction of false alarms. Separate feature vectors were formed for predicting the presence or absence of each arrhythmia, using both spectral and time-domain information. The training and test data were obtained from the Physionet/CinC Challenge 2015 database. Classification algorithms were written for two different categories of data, namely real-time and retrospective, whose data lengths were 10 s and an additional 30 s, respectively. For the real-time test dataset, sensitivity of 94% and specificity of 82% were obtained. Similarly, for the retrospective test dataset, sensitivity of 94% and specificity of 86% were obtained. PMID:27454417

  1. Intramyocardial activation in early ventricular arrhythmias following coronary artery ligation.

    Science.gov (United States)

    Kaplinsky, E; Ogawa, S; Kmetzo, J; Balke, C W; Dreifus, L S

    1980-01-01

    Subendocardial, subepicardial and intramyocardial activation in the ischemic zone was investigated in 20 anesthetized open chest dogs 0-30 minutes after the ligation of the left anterior descending coronary artery. Single and composite electrograms and lead 2 of the ECG were recorded. Coronary artery ligation produced marked delay, fragmentation, and reduction in amplitude in the electrical activity of the subepicardial and intramyocardial muscle layers. The activation remained synchronous in the subendocardial muscle layers. Extension of electrical activity in the ischemic subepicardium and intramyocardium beyond the T wave of the surface ECG preceded the onset of immediate ventricular arrhythmias (IVA) during the initial ten minute period after coronary artery ligation. However, a second surge of delayed ventricular arrhythmias (DVA), 10-30 minutes after ligation, was not associated with the appearance of diastolic electrical activity in any of the subepicardial or myocardial layers. It appears that subepicardial as well as intramyocardial reentry could play an important role in the genesis of the immediate ventricular arrhythmias (1-10 minutes after ligation). In contrast, no obvious reentrant activity as evidenced by delayed and fragmented electrical activity could be observed in the electrogram from any of the myocardial electrical activity could be observed in the electrogram from any of the myocardial layers with the appearance of delayed ventricular ectopic activity 10-30 minutes after ligation.

  2. Detection of Shockable Ventricular Arrhythmia using Variational Mode Decomposition.

    Science.gov (United States)

    Tripathy, R K; Sharma, L N; Dandapat, S

    2016-04-01

    Ventricular tachycardia (VT) and ventricular fibrillation (VF) are shockable ventricular cardiac ailments. Detection of VT/VF is one of the important step in both automated external defibrillator (AED) and implantable cardioverter defibrillator (ICD) therapy. In this paper, we propose a new method for detection and classification of shockable ventricular arrhythmia (VT/VF) and non-shockable ventricular arrhythmia (normal sinus rhythm, ventricular bigeminy, ventricular ectopic beats, and ventricular escape rhythm) episodes from Electrocardiogram (ECG) signal. The variational mode decomposition (VMD) is used to decompose the ECG signal into number of modes or sub-signals. The energy, the renyi entropy and the permutation entropy of first three modes are evaluated and these values are used as diagnostic features. The mutual information based feature scoring is employed to select optimal set of diagnostic features. The performance of the diagnostic features is evaluated using random forest (RF) classifier. Experimental results reveal that, the feature subset derived from mutual information based scoring and the RF classifier produces accuracy, sensitivity and specificity values of 97.23 %, 96.54 %, and 97.97 %, respectively. The proposed method is compared with some of the existing techniques for detection of shockable ventricular arrhythmia episodes from ECG. PMID:26798076

  3. Life-threatening ventricular arrhythmia recognition by nonlinear descriptor

    Directory of Open Access Journals (Sweden)

    Krishnan Shankar

    2005-01-01

    Full Text Available Abstract Background Ventricular tachycardia (VT and ventricular fibrillation (VF are ventricular cardiac arrhythmia that could be catastrophic and life threatening. Correct and timely detection of VT or VF can save lives. Methods In this paper, a multiscale-based non-linear descriptor, the Hurst index, is proposed to characterize the ECG episode, so that VT and VF can be recognized as different from normal sinus rhythm (NSR in the descriptor domain. Results This newly proposed technique was tested using MIT-BIH malignant ventricular arrhythmia database. The relationship between the ECG episode length and the corresponding recognition performance was studied. The experiments demonstrated good performance of the proposed descriptor. An accuracy rate as high as 100% was obtained for VT/VF to be recognized from NSR; for VT and VF to be recognized from each other, the recognition accuracy varies from 84.24% to 100%. In addition, the results were compared favorably against those obtained using Complexity measure. Conclusions There is strong potential for using the Hurst index for malignant ventricular arrhythmia recognition in clinical applications.

  4. Effects of antiarrhythmic peptide 10 on acute ventricular arrhythmia

    Institute of Scientific and Technical Information of China (English)

    Bing Sun; Jin-Fa Jiang; Cui-Mei Zhao; Chao-Hui Hu

    2015-01-01

    Objective:To observe the effects antiarrhythmic peptide 10 (AAP10) aon acute ventricular arrhythmia and the phosphorylation state of ischemic myocardium connexin.Methods:Acute total ischemia and partial ischemia models were established by ceasing perfusion and ligating the left anterior descending coronary artery in SD rats. The effects of AAP10 (1 mg/L) on the incidence rate of ischemia-induced ventricular arrhythmia were observed. The ischemic myocardium was sampled to detect total-Cx43 and NP-Cx43 by immunofluorescent staining and western blotting. the total-Cx43 expression was detected through image analysis system by semi-quantitative analysis.Results: AAP10 could significantly decrease the incidence of ischemia-induced ventricular tachycardia and ventricular fibrillation. During ischemic stage, total ischemia (TI) and AAP10 total ischemia (ATI) groups were compared with partial ischemia (PI) and AAP10 partial ischemia (API) groups. The rates of incidence for arrhythmia in the ATI and API groups (10% and 0%) were lower than those in the TI and PI groups (60% and 45%). The difference between the two groups was statistically significant (P=0.019, P=0.020). The semi-quantitative analysis results of the ischemic myocardium showed that the total-Cx43 protein expression distribution areas for TI, ATI, PI and API groups were significantly decreased compared with the control group. On the other hand, the NP-Cx43 distribution areas of TI, ATI, PI and API groups were significantly increased compared with the control group (P>0.05). AAP10 could increase the total-Cx43 expression in the ischemic area and decrease the NP-Cx43 expression. Western blot results were consistent with the results of immunofluorescence staining.Conclusions:AAP10 can significantly decrease the rate of incidence of acute ischemia-induced ventricular tachycardia and ventricular fibrillation. Acute ischemic ventricular arrhythmias may have a relationship with the decreased phosphorylation of Cx43

  5. Surveillance of fetal arrhythmias in the outpatient setting: current limitations and call for action.

    Science.gov (United States)

    Freire, Grace

    2015-12-01

    Surveillance of fetal arrhythmias in the outpatient setting remains limited by lack of monitoring modalities. Despite technological advances made in the field of obstetrics, existing devices are not currently suitable to monitor fetal arrhythmias. In this report, the author describes the current and developing fetal heart rate monitoring technologies including the recent introduction of hand-held Doppler monitors for outpatient surveillance of fetal arrhythmias.

  6. Left Ventricular Dilatation Increases the Risk of Ventricular Arrhythmias in Patients With Reduced Systolic Function

    OpenAIRE

    Aleong, Ryan G.; Mulvahill, Matthew J; Halder, Indrani; Carlson, Nichole E; Singh, Madhurmeet; Bloom, Heather L.; Dudley, Samuel C.; Ellinor, Patrick T.; Shalaby, Alaa; Weiss, Raul; Gutmann, Rebecca; Sauer, William H.; Narayanan, Kumar; Chugh, Sumeet S.; Saba, Samir

    2015-01-01

    Background Reduced left ventricular (LV) ejection fraction increases the risk of ventricular arrhythmias; however, LV ejection fraction has a low sensitivity to predict ventricular arrhythmias. LV dilatation and mass may be useful to further risk-stratify for ventricular arrhythmias. Methods and Results Patients from the Genetic Risk of Assessment of Defibrillator Events (GRADE) study (N =930), a study of heart failure subjects with defibrillators, were assessed for appropriate implantable ca...

  7. The Effect of Opium Addiction on Arrhythmia Following Acute Myocardial Infarction

    OpenAIRE

    Mostafa Shokoohi; Hamid Najafipour; Afsaneh Forood; Morvarid Dadras; Fatemeh Mirzaiepour

    2012-01-01

    The effect of opium addiction on the appearance of different types of arrhythmias after acute myocardial infarction (AMI) has been assessed in few studies. This study is aimed to determine the effect of opium on post-MI arrhythmia and also to address the differences in the appearance of different types of arrhythmias after AMI between opium addicted and non-addicted patients. In this comparative study, participants were classified into two groups with opium addiction (n=94) and without opium ...

  8. Hospital discharge diagnoses of ventricular arrhythmias and cardiac arrest were useful for epidemiologic research

    DEFF Research Database (Denmark)

    De Bruin, M L; van Hemel, N M; Leufkens, H G M;

    2005-01-01

    OBJECTIVE: We investigated the validity of hospital discharge diagnosis regarding ventricular arrhythmias and cardiac arrest. METHODS: We identified patients whose record in the PHARMO record linkage system database showed a code for ventricular or unspecified cardiac arrhythmias according to cod...... according to ICD-9-CM as paroxysmal ventricular tachycardia, ventricular fibrillation, ventricular flutter, ventricular premature beats, or cardiac arrest) have a high PPV and are useful for selecting events in epidemiological studies on drug-induced arrhythmias....

  9. Clinical application of echocardiography in detection of foetal arrhythmia:a retrospective study of 451 foetuses

    Institute of Scientific and Technical Information of China (English)

    赵博文; 张松英; 潘美; 徐海珊; 寿金朵; 吕江红; 汤富刚; 范妙英; 范晓明; 林莎

    2004-01-01

    @@Foetal arrhythmia is defined as any irregular foetal cardiac rhythm or regular rhythm at a rate outside the reference range of 120 to 160 beats/minute. Foetal echocardiography permits accurate determination of the structural characteristics and the nature of the arrhythmia in foetuses. It is particularly indicated for mothers from high-risk groups. Management of diagnosed heart disease, including foetal arrhythmia, leads either to the termination of pregnancy or to optimal postnatal care of baby and mother. This retrospective study examined the application of foetal echocardiography in the diagnosis of foetal arrhythmia and its clinical significance.

  10. Atrial and ventricular function in thalassemic patients with supraventricular arrhythmias

    Directory of Open Access Journals (Sweden)

    Vitantonio Di Bello

    2009-04-01

    Full Text Available The aims of this study were to evaluate through Color Doppler Myocardial Imaging (CDMI echocardiography if atrial or ventricular myocardial alterations could be detectable in patients with thalassemia major (THAL and if these alterations could be considered as predictive elements for supra-ventricular arrhythmic events. Twenty-three patients with THAL underwent clinical and electrocardiographic evaluation; patients were grouped in THAL1 (9 with supra-ventricular arrhythmias and THAL2 (14 without arrhythmias; 12 healthy subjects were considered as control group (C. We examined through conventional 2D Color Doppler echocardiography some morphological and functional parameters regarding left ventricular (LV systolic and diastolic function, and through CDMI the velocities at mitral annulus level, the regional LV and left atrial (LA strain and strain rate. All THAL patients had LV dimension (pless than 0.05, LA area (p less than 0.01 and E/Em ratio (pless than 0.001 to be significantly higher than controls. The mitral annulus longitudinal velocities were significantly lower in THAL1 than in THAL2 (pless than 0.001; the E/Em ratio was higher in THAL1 than THAL2 (pless than 0.001. The THAL1 showed a lower systolic strain rate of atrial wall than THAL2 and C (pless than 0.05. The multiple regression highlighted a significantly inverse correlation among E/Em and atrial strain (pless than 0.02. CDMI showed both THAL subgroups had subtle systolic and diastolic left ventricular myocardial alterations, which could represent the onset of developing “iron cardiomyopathy” and are related to supra-ventricular arrhythmia. Monitoring these parameters in the THAL patients could contribute to decisions about follow-up and therapy.

  11. [Emergency treatment of arrhythmias in neonates and infants].

    Science.gov (United States)

    Weber, H; Wesselhoeft, H; Eigster, G

    1983-11-01

    Emergency treatment of cardiac arrhythmias was required in 41 newborn and infants aged two days to 9 months (mean 77 days) from July 1977 until September 1981. Heart defects were present in 27 (65.8%). Invasive electrophysiological studies were performed in all patients. The different types of arrhythmias were: bradyarrhythmias in 9 (21.9%): bradycardia to cardiac arrest (5), congenital complete AV-block (3), postoperative complete AV-block (1). Tachyarrhythmias in 32 patients (78.1%): reentry through accessory connections (21), congenital atrial flutter (6), ventricular flutter/fibrillation (3), and AV-nodal tachycardia (2). Overdrive atrial or ventricular stimulation with a consecutive series of 15-20 impulses of 5-10 Volts abolished arrhythmic attacks in 22 patients including 4 in whom prior digitalization had no effect. In two other patients overdrive pacing achieved sinus rhythm only after i.v. Propafenon. In 4 further patients 36.2 to 63.8 mg/m2 i.v. Propafenon and in 4 other patients DC synchronized cardioversion with 1 to 3 Wsec/kg restored a normal heart rate. The 3 patients with congenital complete heart block died, one despite permanent pacing. Oral Propafenon therapy with 300 mg/m2 die in three divided doses following emergency therapy of tachyarrhythmias was discontinued in patients without arrhythmias after 1 year on drug therapy. There was no relapse after a mean follow-up period of 1.9 years. Only patients with congestive heart failure due to cardiac defects needed additional digitalisation. Thus, in our experience antiarrhythmic drug therapy with Propafenon was more effective in this age group than digitalization. PMID:6664346

  12. Poincare Geometry-Characterized Arrhythmia Identification Scheme in Grid

    OpenAIRE

    Dong-Hyun Kim; Jin-Ho Kim; Chan-Hyun Youn.

    2009-01-01

    In this paper, we propose a new scheme of Poincare geometry-characterized ECG analysis for cardiac disease identification. Based on reliable P-wave detection we created P-P Poincare plot applying P-P intervals of ECG signal. By the new geometric Poincare plot analysis, which combines R-R intervals and P-P intervals, weidentified geometric differences of normal and arrhythmia ECG databases at PhysioBank in Physionet. Poincare descriptors show that the analysis scheme can classify two ECG signa...

  13. Artifact versus arrhythmia in pseudo-polymorphic tachycardia; case report

    Directory of Open Access Journals (Sweden)

    Ahmed V

    2015-04-01

    Full Text Available Vaseem Ahmed, Anish Patel, Abhishek Sharma, Dennis Bloomfield Department of Medicine, Richmond University Medical Center, Staten Island, NY, USA Abstract: We present the case of a young male patient in sinus rhythm whose electrocardiogram (ECG was initially misinterpreted as ventricular tachycardia. Electrocardiographic artifact appearing to be ventricular tachycardia commonly occurs and ECG criteria have been described to aid in the discrimination between artifact and true arrhythmia. There are many causes of artifacts and prompt recognition is important to prevent unnecessary interventions. Keywords: artifact, ventricular tachycardia, pseudo-ventricular tachycardia, notch sign, sinus sign

  14. Cardiac arrhythmias during fiberoptic bronchoscopy and relation with oxygen saturation

    Directory of Open Access Journals (Sweden)

    Hassan G

    2005-01-01

    Full Text Available To evaluate the occurrence of electrocardiographic abnormalities during fiberoptic bronchoscopy, in relation to specific stages of the procedures, patients′ age, sex, smoking, pre-existing lung disease, premedication and oxygen saturation, a prospective study was conducted on 56 patients aged 35 to 75 (mean 62 years without pre-existing cardiovascular disease. Patients were connected to a 12-lead computerized electrocardiographic recorder and pulse oximeter. Fall of oxygen saturation from mean of 95.12% before the procedure to below 80% was observed in 12 (21.4% patients and below 75% in 5 (8.9% patients, at various stages. Statistically highly significant (p < 0.001 fall of oxygen saturation was observed during the procedures while bronchoscope was introduced into the airways and tracheobronchial tree examined. Major disturbances of cardiac rhythm (i.e. atrial, ventricular or both developed in 23 (41.07% patients. Out of these, sinus tachycardia was noted in 16 (69.5%, ventricular premature complexes in 5 (21.7% and paroxysmal supraventricular tachycardia in 2 (8.6% patients. Arrhythmias were most frequent in association with periods of maximum oxygen desaturation in 18 (78.2% of these 23 patients. Oxygen desaturation persisted for more than half an hour in 38 (67.8% of the 56 patients. However, no correlation was observed between the frequency of arrhythmias during bronchoscopy and patients′ age, sex pre-medication or pre-existing pulmonary disease.

  15. Heart rate turbulence and variability in patients with ventricular arrhythmias

    Directory of Open Access Journals (Sweden)

    Diego Tarricone

    2009-08-01

    Full Text Available Background: To evaluate the changes in autonomic neural control mechanisms before malignant ventricular arrhythmias, we measured heart rate variability (HRV and heart rate turbulence (HRT in patients with ventricular tachycardia or fibrillation (Group I; n=6, non sustained ventricular tachycardia (Group II; n=32, frequent premature ventricular beats (Group III; n=26 and with ICD implantation (Group IV; n=11. Methods: Time domain parameters of HRV and turbulence onset (TO and slope (TS were calculated on 24 hour Holter recordings. Normal values were: SDNN > 70 msec for HRV, TO <0% and TS >2.5 msec/RR-I for HRT. Results: Whereas SDNN was within normal range and similar in all study groups, HRT parameters were significantly different in patients who experienced VT/VF during Holter recording. Abnormal TO and/or TS were present in 100% of Group I patients and only in about 50% of Group II and IV. On the contrary, normal HRT parameters were present in 40-70% of Group II, III and IV patients and none of Group I. Conclusions: These data suggest that HRT analysis is more suitable than HRV to detect those transient alterations in autonomic control mechanisms that are likely to play a major trigger role in the genesis of malignant cardiac arrhythmias. (Heart International 2007; 3: 51-7

  16. Evaluation and management of arrhythmia in the athletic patient.

    Science.gov (United States)

    Lampert, Rachel

    2012-01-01

    Athletes may present with palpitations, syncope, or arrest resulting in the diagnosis of arrhythmia, or screening may result in diagnosis of conditions with predisposition to arrhythmia. This chapter focuses on 3 common arrhythmic conditions in athletes-atrial fibrillation, premature ventricular contractions (PVCs), and the athlete with an implanted device. (1) Atrial fibrillation: most studies show that atrial fibrillation is more common in competitive athletes, particularly those participating in long-term endurance sports. Postulated mechanisms include morphologic changes such as atrial dilatation, autonomic changes such as increased vagal tone, or inflammatory changes due to sports participation. Treatment options include long-term antiarrhythmic agents, "pill in the pocket" medications, or radiofrequency ablation, a highly successful procedure in athletes. (2) Premature ventricular contractions: data conflict on whether the incidence of PVCs is increased in highly trained individuals. Very frequent PVCs in athletes, however, can be a manifestation of underlying heart disease, and athletes presenting with PVCs should undergo evaluation. In the absence of underlying heart disease, PVCs do not carry a poor prognosis, and US guidelines do not recommend restriction from sports. (3) Implanted devices: the safety of sports for the athlete with an implanted device is unknown, and current guidelines recommend against participation in vigorous competitive sports, based on postulated risks including failure to defibrillate and risk of injury. Many athletes with defibrillators and pacemakers do participate in sports. Ongoing research will better delineate the risks of sports for the athlete with an implanted device. PMID:22386293

  17. Risk prediction of ventricular arrhythmias and myocardial function in Lamin A/C mutation positive subjects

    DEFF Research Database (Denmark)

    Hasselberg, Nina E; Edvardsen, Thor; Petri, Helle;

    2014-01-01

    Mutations in the Lamin A/C gene may cause atrioventricular block, supraventricular arrhythmias, ventricular arrhythmias (VA), and dilated cardiomyopathy. We aimed to explore the predictors and the mechanisms of VA in Lamin A/C mutation-positive subjects.METHODS AND RESULTS: We included 41 Lamin A...

  18. The risk of arrhythmias following coronary artery bypass surgery: do smokers have a paradox effect?

    LENUS (Irish Health Repository)

    Al-Sarraf, Nael

    2010-11-01

    Smoking is reported to increase the risk of arrhythmias. However, there are limited data on its effects on arrhythmias following coronary artery bypass graft (CABG). This is a retrospective review of a prospective database of all CABG patients over an eight-year period. Our cohort (n=2813) was subdivided into: current (n=1169), former (n=837), and non-smokers (n=807). Predictors of arrhythmias following CABG in relation to smoking status were analysed. Atrial arrhythmias occurred in 942 patients (33%). Ventricular arrhythmias occurred in 48 patients (2%) and high-grade atrioventricular block occurred in five patients (0.2%). Arrhythmias were lower in current smokers than former and non-smokers (29% vs. 40% vs. 39%, respectively P<0.001). Logistic regression analysis showed 30% arrhythmia risk reduction in smokers compared to non-smokers [odds ratio (OR) 0.7, 95% confidence intervals (CI) 0.5-0.8] and this effect persisted after accounting for potential confounders while former smokers had the same risk as non-smokers (OR 1.04, CI 0.9-1.3). There were no significant differences in mortality. Smokers are less prone to develop arrhythmias following CABG. This paradox effect is lost in former smokers. This effect is possibly due to a lower state of hyper adrenergic stimulation observed in smokers than non-smokers following the stress of surgery.

  19. Novel energy modalities for catheter ablation of cardiac arrhythmias : Pitfalls and possibilities of potent power sources

    NARCIS (Netherlands)

    Neven, K.G.E.J.

    2014-01-01

    The acceptance of catheter ablation as treatment for cardiac arrhythmias is amongst others dependent on its success rate, a high initial success rate will increase physician and patient acceptance. One of the reasons why recurrence of arrhythmia after ablation is substantial is non-transmurality of

  20. Long-term recording of cardiac arrhythmias with an implantable cardiac monitor in patients with reduced ejection fraction after acute myocardial infarction: the Cardiac Arrhythmias and Risk Stratification After Acute Myocardial Infarction (CARISMA) study

    DEFF Research Database (Denmark)

    Bloch Thomsen, Poul Erik; Jons, Christian; Raatikainen, M J Pekka;

    2010-01-01

    Knowledge about the incidence of cardiac arrhythmias after acute myocardial infarction has been limited by the lack of traditional ECG recording systems to document and confirm asymptomatic and symptomatic arrhythmias. The Cardiac Arrhythmias and Risk Stratification After Myocardial Infarction...... (CARISMA) trial was designed to study the incidence and prognostic significance of arrhythmias documented by an implantable cardiac monitor among patients with acute myocardial infarction and reduced left ventricular ejection fraction....

  1. Link between Hypoglycemia and Cardiac Arrhythmias: An Answer to Why Tight Glycemic Control May Increase Mortality in ...

    Science.gov (United States)

    ... Size: A A A Listen The Link Between Hypoglycemia and Cardiac Arrhythmias: An Answer to Why Tight ... from the University of Sheffield found that overnight hypoglycemia was associated with increased susceptibility to cardiac arrhythmias ...

  2. Aconitine Challenge Test Reveals a Single Exposure to Air Pollution Causes Increased Cardiac Arrhythmia Risk in Hypertensive Rats - Abstract

    Science.gov (United States)

    Epidemiological studies demonstrate a significant association between arrhythmias and air pollution exposure. Sensitivity to aconitine-induced arrhythmia has been used repeatedly to examine the factors that increase the risk of such cardiac electrical dysfunction. In this study, ...

  3. A Novel Automatic Detection System for ECG Arrhythmias Using Maximum Margin Clustering with Immune Evolutionary Algorithm

    Directory of Open Access Journals (Sweden)

    Bohui Zhu

    2013-01-01

    Full Text Available This paper presents a novel maximum margin clustering method with immune evolution (IEMMC for automatic diagnosis of electrocardiogram (ECG arrhythmias. This diagnostic system consists of signal processing, feature extraction, and the IEMMC algorithm for clustering of ECG arrhythmias. First, raw ECG signal is processed by an adaptive ECG filter based on wavelet transforms, and waveform of the ECG signal is detected; then, features are extracted from ECG signal to cluster different types of arrhythmias by the IEMMC algorithm. Three types of performance evaluation indicators are used to assess the effect of the IEMMC method for ECG arrhythmias, such as sensitivity, specificity, and accuracy. Compared with K-means and iterSVR algorithms, the IEMMC algorithm reflects better performance not only in clustering result but also in terms of global search ability and convergence ability, which proves its effectiveness for the detection of ECG arrhythmias.

  4. Towards a hierarchy of mechanisms in CaMKII-mediated arrhythmia

    Directory of Open Access Journals (Sweden)

    Kevin P Vincent

    2014-05-01

    Full Text Available CaMKII activity has been shown to contribute to arrhythmogenesis in a remarkably broad range of cardiac pathologies. Several of these involve significant structural and electrophysiologic remodeling, whereas others are due to specific channelopathies, and are not typically associated with arrhythmogenic changes to protein expression or cellular and tissue structure. The ability of CaMKII to contribute to arrhythmia across such a broad range of phenotypes suggests one of two interpretations regarding the role of CaMKII in cardiac arrhythmia: (1 some CaMKII-dependent mechanism is a common driver of arrhythmia irrespective of the specific etiology of the disease, or (2 these different etiologies expose different mechanisms by which CaMKII is capable of promoting arrhythmia. In this review, we dissect the available mechanistic evidence to explore these two possibilities and discuss how the various molecular actions of CaMKII promote arrhythmia in different pathophysiologic contexts.

  5. Ambulatory Cardiac Monitoring for Discharged Emergency Department Patients with Possible Cardiac Arrhythmias

    Directory of Open Access Journals (Sweden)

    Donald Scheiber

    2014-03-01

    Full Text Available Introduction: Many emergency department (ED patients have symptoms that may be attributed to arrhythmias, necessitating outpatient ambulatory cardiac monitoring. Consensus is lacking on the optimal duration of monitoring. We describe the use of a novel device applied at ED discharge that provides continuous prolonged cardiac monitoring. Methods: We enrolled discharged adult ED patients with symptoms of possible cardiac arrhythmia. A novel, single use continuous recording patch (Zio®Patch was applied at ED discharge. Patients wore the device for up to 14 days or until they had symptoms to trigger an event. They then returned the device by mail for interpretation. Significant arrhythmias are defined as: ventricular tachycardia (VT ≥4 beats, supraventricular tachycardia (SVT ≥4 beats, atrial fibrillation, ≥3 second pause, 2nd degree Mobitz II, 3rd degree AV Block, or symptomatic bradycardia. Results: There were 174 patients were enrolled and all mailed back their devices. The average age was 52.2 (± 21.0 years, and 55% were female. The most common indications for device placement were palpitations 44.8%, syncope 24.1% and dizziness 6.3%. Eighty-three patients (47.7% had ≥1 arrhythmias and 17 (9.8% were symptomatic at the time of their arrhythmia. Median time to first arrhythmia was 1.0 days (IQR 0.2-2.8 and median time to first symptomatic arrhythmia was 1.5 days (IQR 0.4-6.7. 93 (53.4% of symptomatic patients did not have any arrhythmia during their triggered events. The overall diagnostic yield was 63.2% Conclusion: The Zio®Patch cardiac monitoring device can efficiently characterize symptomatic patients without significant arrhythmia and has a higher diagnostic yield for arrhythmias than traditional 24-48 hour Holter monitoring. It allows for longer term monitoring up to 14 days. [West J Emerg Med. 2014;15(2:194–198.

  6. Infarct size and recurrence of ventricular arrhythmias after defibrillator implantation

    Energy Technology Data Exchange (ETDEWEB)

    Sutter, J. de; Tavernier, R.; Kazmierckzak, J.; Buyzere, M. de; Clement, D.L. [Department of Cardiology, University Hospital Gent, Gent (Belgium); Wiele, C. van de; Dierckx, R.A. [Department of Nuclear Medicine, University Hospital Gent (Belgium); Jordaens, L. [Thoraxcenter, University Hospital Rotterdam-Dijkzigt (Netherlands)

    2000-07-01

    Infarct size as determined by perfusion imaging is an independent predictor of mortality after implantable cardioverter defibrillator (ICD) implantation in patients with coronary artery disease (CAD) and life-threatening ventricular arrhythmias (VA). However, its value as a predictor of VA recurrence and hospitalisation after ICD implantation is unknown. Therefore, the objective of this study was to evaluate whether infarct size as determined by perfusion imaging can help to identify patients who are at high risk for recurrence of VA and hospitalisation after ICD implantation. We studied 56 patients with CAD and life-threatening VA. Before ICD implantation, all patients underwent a uniform study protocol including a thallium-201 stress-redistribution perfusion study. A defect score as a measurement of infarct size was calculated using a 17-segment 5-point scoring system. Study endpoints during follow-up were documented episodes of appropriate anti-tachycardia pacing and/or shocks for VA and cardiac hospitalisation for electrical storm (defined as three or more appropriate ICD interventions within 24 h), heart failure or angina. After a mean follow-up of 470{+-}308 days, 22 patients (39%) had recurrences of VA. In univariate analysis, predictors for recurrence were: (a) ventricular tachycardia (VT) as the initial presenting arrhythmia (86% vs 59% for patients without ICD therapy, P=0.04), (b) treatment with {beta}-blockers (36% vs 68%, P=0.03) and (c) a defect score (DS) {>=}20 (64% vs 32%, P=0.03). In multivariate analysis, VT as the presenting arrhythmia ({chi}2=5.51, P=0.02) and a DS {>=}20 ({chi}2=4.22, P=0.04) remained independent predictors. Cardiac hospitalisation was more frequent in patients with a DS {>=}20 (44% vs 13% for patients with DS <20, P=0.015) and this was particularly due to more frequent hospitalisations for electrical storm (24% vs 3% for patients with DS<20, P=0.037). The extent of scarring determined by perfusion imaging can separate

  7. Flecainide: Current status and perspectives in arrhythmia management

    Institute of Scientific and Technical Information of China (English)

    George; K; Andrikopoulos; Sokratis; Pastromas; Stylianos; Tzeis

    2015-01-01

    Flecainide acetate is a class IC antiarrhythmic agent and its clinical efficacy has been confirmed by the results of several clinical trials. Nowadays, flecainide is recommended as one of the first line therapies for pharmacological conversion as well as maintenance of sinus rhythm in patients with atrial fibrillation and/or supraventricular tachycardias. Based on the Cardiac Arrhythmia Suppression Trial study results, flecainide is not recommended in patients with structural heart disease due to high proarrhythmic risk. Recent data support the role of flecainide in preventing ventricular tachyarrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia associated both with ryanodine receptor and calsequestrin mutations. We herein review the current clinical data related to flecainide use in clinical practice and some concerns about its role in the management of patients with coronary artery disease.

  8. Serious arrhythmias in patients with apical hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    We report cases of serious arrhythmias associated with apical hypertrophic cardiomyopathy (AHCM). Thirty-one patients were referred to our institute to undergo further assessment of their AHCM from 1988 to 1999. Three patients with nonsustained ventricular tachycardia demonstrated an 123I-MIBG regional reduction in the tracer uptake. In two patients with ventricular fibrillation (VF), the findings from 123I-MIBG imaging revealed regional sympathetic denervation in the inferior and lateral regions. Electrophysiologic study demonstrated reproducible induction of VF in aborted sudden death and presyncopal patients, resulting in the need for an implantable defibrillator device and amiodarone in each patient. Patients with refractory atrial fibrillation with a rapid ventricular response suffered from serious congestive heart failure. A prudent assessment and strategy in patients with this disease would be indispensable in avoiding a disastrous outcome. (author)

  9. Propofol and arrhythmias: two sides of the coin

    Institute of Scientific and Technical Information of China (English)

    Qiang LIU; Ai-ling KONG; Rong CHEN; Cheng QIAN; Shao-wen LIU; Bao-gui SUN; Le-xin WANG; Long-sheng SONG; Jiang HONG

    2011-01-01

    The hypnotic agent propofol is effective for the induction and maintenance of anesthesia. However, recent studies have shown that propofol administration is related to arrhythmias. Propofol displays both pro- and anti-arrhythmic effects in a concentration-dependent manner. Data indicate that propofol can convert supraventricular tachycardia and ventricular tachycardia and may inhibit the conduction system of the heart. The mechanism of the cardiac effects remains poorly defined and may involve ion channels, the autonomic nervous system and cardiac gap junctions. Specifically, sodium, calcium and potassium currents in cardiac cells are suppressed by clinically relevant concentrations of propofol. Propofol shortens the action potential duration (APD) but lessens the ischemia-induced decrease in the APD. Furthermore, propofol suppresses both sympathetic and parasympathetic tone and preserves gap junctions during ischemia. All of these effects cumulatively contribute to the antiarrhythmic and proarrhythmic properties of propofol.

  10. Spectral analysis of sinus arrhythmia - A measure of mental effort

    Science.gov (United States)

    Vicente, Kim J.; Craig Thornton, D.; Moray, Neville

    1987-01-01

    The validity of the spectral analysis of sinus arrhythmia as a measure of mental effort was investigated using a computer simulation of a hovercraft piloted along a river as the experimental task. Strong correlation was observed between the subjective effort-ratings and the heart-rate variability (HRV) power spectrum between 0.06 and 0.14 Hz. Significant correlations were observed not only between subjects but, more importantly, within subjects as well, indicating that the spectral analysis of HRV is an accurate measure of the amount of effort being invested by a subject. Results also indicate that the intensity of effort invested by subjects cannot be inferred from the objective ratings of task difficulty or from performance.

  11. Developmental trajectories of respiratory sinus arrhythmia: associations with social responsiveness.

    Science.gov (United States)

    Patriquin, Michelle A; Lorenzi, Jill; Scarpa, Angela; Bell, Martha Ann

    2014-04-01

    The present longitudinal study examined relations between respiratory sinus arrhythmia (RSA) development and social responsiveness characteristics associated with autism spectrum disorders. Group-based developmental trajectory modeling was used to characterize RSA development patterns in 106 typically developing children across 5, 10, 24, 36, and 48 months of age. A two-group model fit of RSA development was found: a "typically" and "atypically" developing group. The typical group gradually increased in RSA across 5-48 months of age. The atypical group, however, increased in RSA from 5 to 24 months and demonstrated a plateau or "delay" in RSA development from 24 to 48 months. The atypical RSA development group also demonstrated more difficulties in parent-reported social responsiveness at 48 months. The results support current literature that identifies RSA as a marker of social functioning level. PMID:23341170

  12. Serious arrhythmias in patients with apical hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Okishige, Kaoru; Sasano, Tetsuo; Yano, Kei; Azegami, Kouji; Suzuki, Kou; Itoh, Kuniyasu [Yokohama Red Cross Hospital (Japan)

    2001-05-01

    We report cases of serious arrhythmias associated with apical hypertrophic cardiomyopathy (AHCM). Thirty-one patients were referred to our institute to undergo further assessment of their AHCM from 1988 to 1999. Three patients with nonsustained ventricular tachycardia demonstrated an {sup 123}I-MIBG regional reduction in the tracer uptake. In two patients with ventricular fibrillation (VF), the findings from {sup 123}I-MIBG imaging revealed regional sympathetic denervation in the inferior and lateral regions. Electrophysiologic study demonstrated reproducible induction of VF in aborted sudden death and presyncopal patients, resulting in the need for an implantable defibrillator device and amiodarone in each patient. Patients with refractory atrial fibrillation with a rapid ventricular response suffered from serious congestive heart failure. A prudent assessment and strategy in patients with this disease would be indispensable in avoiding a disastrous outcome. (author)

  13. Proposition of novel classification approach and features for improved real-time arrhythmia monitoring.

    Science.gov (United States)

    Kim, Yoon Jae; Heo, Jeong; Park, Kwang Suk; Kim, Sungwan

    2016-08-01

    Arrhythmia refers to a group of conditions in which the heartbeat is irregular, fast, or slow due to abnormal electrical activity in the heart. Some types of arrhythmia such as ventricular fibrillation may result in cardiac arrest or death. Thus, arrhythmia detection becomes an important issue, and various studies have been conducted. Additionally, an arrhythmia detection algorithm for portable devices such as mobile phones has recently been developed because of increasing interest in e-health care. This paper proposes a novel classification approach and features, which are validated for improved real-time arrhythmia monitoring. The classification approach that was employed for arrhythmia detection is based on the concept of ensemble learning and the Taguchi method and has the advantage of being accurate and computationally efficient. The electrocardiography (ECG) data for arrhythmia detection was obtained from the MIT-BIH Arrhythmia Database (n=48). A novel feature, namely the heart rate variability calculated from 5s segments of ECG, which was not considered previously, was used. The novel classification approach and feature demonstrated arrhythmia detection accuracy of 89.13%. When the same data was classified using the conventional support vector machine (SVM), the obtained accuracy was 91.69%, 88.14%, and 88.74% for Gaussian, linear, and polynomial kernels, respectively. In terms of computation time, the proposed classifier was 5821.7 times faster than conventional SVM. In conclusion, the proposed classifier and feature showed performance comparable to those of previous studies, while the computational complexity and update interval were highly reduced. PMID:27318329

  14. Ventricular Arrhythmias in Apparently Normal Hearts: Who Needs an Implantable Cardiac Defibrillator?

    Science.gov (United States)

    Tan, Alex Y; Ellenbogen, Kenneth

    2016-09-01

    Idiopathic ventricular tachycardia is often considered a benign form of ventricular arrhythmia in patients without apparent structural heart disease. However, a subset of patients may develop malignant ventricular arrhythmias and present with syncope and sudden cardiac arrest. Survivors of cardiac arrest are candidates for implantable cardiac defibrillators (ICDs). The indications for ICDs in patients with less than a full-blown cardiac arrest presentation but with electrocardiographically high-risk ectopy features remain uncertain. This article addresses some of the uncertainties and pitfalls in ICD risk stratification in this patient group and explores potential mechanisms for malignant conversion of benign premature ventricular complexes to sustained arrhythmia.

  15. Spectrum of Ventricular Arrhythmias Arising from Papillary Muscle in the Structurally Normal Heart.

    Science.gov (United States)

    Naksuk, Niyada; Kapa, Suraj; Asirvatham, Samuel J

    2016-09-01

    Papillary muscle is an endocavitary structure that can give rise to ventricular arrhythmias in a structurally normal heart. Its manifestation is generally benign. The papillary muscle's complex anatomy and the presence of intermixed Purkinje fibers can create a substrate for idiopathic ventricular fibrillation. Although differentiating ventricular arrhythmias originating from the papillary muscle and the fascicles is challenging and not always possible, the distinction may be helpful for planning ablation. The propensity for difficulty with ablation of papillary arrhythmias results in a variable success rate. Improvement in techniques to stabilize the catheter, use of imaging, and methods of energy delivery are required to improve ablation outcomes. PMID:27521089

  16. Recurrence of arrhythmia following short-term oral AMIOdarone after CATheter ablation for atrial fibrillation

    DEFF Research Database (Denmark)

    Darkner, Stine; Chen, Xu; Hansen, Jim;

    2014-01-01

    AIMS: Patients undergoing catheter ablation for atrial fibrillation (AF) often experience recurrent arrhythmias within the first few months post-ablation. We aimed to investigate whether short-term use of amiodarone to prevent early arrhythmias following radiofrequency ablation for AF could reduce...... period. CONCLUSION: Short-term oral amiodarone treatment following ablation for paroxysmal or persistent AF did not significantly reduce recurrence of atrial tachyarrhythmias at the 6-month follow-up, but it more than halved atrial arrhythmia related hospitalization and cardioversion rates during...

  17. Influence of calcium preconditioning and streptomycin on ventricular dilation-induced arrhythmias in isolated rat hearts

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To investigate the mechanism of ventricular dilation-induced arrhythmias by dilating isolated rat hearts. Methods Isolated rat hearts were perfused by Langerdorff method. After equilibration, 80 hearts were randomly divided into four groups as follows: (1) control group (n=20), (2) Ca2+ preconditioning (CPC) group (n=20), (3) streptomycin group (n=20), and (4) CPC + streptomycin group (n=20). A latex balloon which can be filled with fluid was anchored in the left ventricle through the left atrium and mitral valve. Epicardial ECG of the left ventricle, left ventricular pressure, coronary flow and heart rate were recorded before and during ventricular dilation by injecting fluid into the latex balloon. The rate and duration of ventricular dilation-induced arrhythmias were recorded. Results Under the same increase in ventricular end-diastolic pressure made by inflation of the balloon, the rate of arrhythmias was 100% and duration of arrhythmias was 2.56±0.46 s in the control group. Both the rates of premature ventricular beat (90 %) and ventricular tachycardia 70 % ) were high. Compared with the control group, the total rate (60 % ) of arrhythmias was lower, and duration (1.67±0.61 s ) of arrhythmias was shorter in the CPC group. Both the rates of premature ventricular beat (60%) and ventricular tachycardia (40%) were low comparatively. The rate of arrhythmias (45 %) was lower and duration ( 1.64±0.42 s)of arrhythmias was shorter, and the rates of premature ventricular beat (30 % ) or ventricular tachycardia (35 %) were lower in the streptomycin group than in the control one. The least ventricular dilation-induced arrhythmias occurred in the CPC + streptomycin group. The rate of arrhythmias (10%) was the lowest and duration (1.01±0.37s) of arrhythmias was the shortest; both the rates of premature ventricular beat (5%) and ventricular tachycardia (10%) were the lowest. Conclusions Ventricular dilation may induce arrhythmias in isolated rat hearts. Stretch

  18. Ventricular Arrhythmias in Apparently Normal Hearts: Who Needs an Implantable Cardiac Defibrillator?

    Science.gov (United States)

    Tan, Alex Y; Ellenbogen, Kenneth

    2016-09-01

    Idiopathic ventricular tachycardia is often considered a benign form of ventricular arrhythmia in patients without apparent structural heart disease. However, a subset of patients may develop malignant ventricular arrhythmias and present with syncope and sudden cardiac arrest. Survivors of cardiac arrest are candidates for implantable cardiac defibrillators (ICDs). The indications for ICDs in patients with less than a full-blown cardiac arrest presentation but with electrocardiographically high-risk ectopy features remain uncertain. This article addresses some of the uncertainties and pitfalls in ICD risk stratification in this patient group and explores potential mechanisms for malignant conversion of benign premature ventricular complexes to sustained arrhythmia. PMID:27521094

  19. The predictive value of CHADS₂ risk score in post myocardial infarction arrhythmias - a Cardiac Arrhythmias and RIsk Stratification after Myocardial infArction (CARISMA) substudy

    DEFF Research Database (Denmark)

    Ruwald, Anne Christine; Gang, Uffe; Thomsen, Poul Erik Bloch;

    2014-01-01

    ventricular ejection fraction (LVEF) ≤40%. All patients were implanted with an implantable cardiac monitor (ICM) within 5 to 21 days post-MI and followed every three months for two years. Atrial fibrillation, bradyarrhythmias and ventricular tachycardias were diagnosed using the ICM, pacemaker or ICD......BACKGROUND: Previous studies have shown substantially increased risk of cardiac arrhythmias and sudden cardiac death in post-myocardial infarction (MI) patients. However it remains difficult to identify the patients who are at highest risk of arrhythmias in the post-MI setting. The purpose...... of this study was to investigate if CHADS₂ score (congestive heart failure, hypertension, age ≥75 years, diabetes and previous stroke/TCI [doubled]) can be used as a risk tool for predicting cardiac arrhythmias after MI. METHODS: The study included 297 post-MI patients from the CARISMA study with left...

  20. Extracellular photosensitization reaction progress and effect on myocardial cell necrosis for arrhythmia treatment application

    Science.gov (United States)

    Ogawa, Emiyu; Takahashi, Mei; Ito, Arisa; Arai, Tsunenori

    2013-06-01

    We investigated detailed extracellular photosensitization reaction effect on rat myocardial cells and the photosensitization reaction progress in a well to study a new application of photodynamic therapy for arrhythmia therapy.

  1. Induced pluripotent stem cell-derived cardiomyocytes: boutique science or valuable arrhythmia model?

    Science.gov (United States)

    Knollmann, Björn C

    2013-03-15

    This article reviews the strengths and limitations of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) as models of cardiac arrhythmias. Specifically, the article attempts to answer the following questions: Which clinical arrhythmias can be modeled by iPSC-CM? How well can iPSC-CM model adult ventricular myocytes? What are the strengths and limitations of published iPSC-CM arrhythmia models? What new mechanistic insight has been gained? What is the evidence that would support using iPSC-CM to personalize antiarrhythmic drug therapy? The review also discusses the pros and cons of using the iPSC-CM technology for modeling specific genetic arrhythmia disorders, such as long QT syndrome, Brugada Syndrome, or Catecholaminergic Polymorphic Ventricular Tachycardia. PMID:23569106

  2. Dipyridamole-thallium tests are predictive of severe cardiac arrhythmias in patients with left ventricular hypertrophy

    International Nuclear Information System (INIS)

    In a population of patients with chronic renal failure (CRF) and a high prevalence of left ventricular hypertrophy (LVH) undergoing chronic hemodialysis, the authors investigated the association between the results of dipyridamole-thallium tests (DTTs) and the occurrence of ventricular arrhythmias. They observed a positive significant association between positive DTTs and the occurrence of severe forms of ventricular arrhythmias. A significant association was also observed between the presence of severe LVH and the occurrence of severe ventricular arrhythmias. However, no association was found between the presence of LVH and the positivity of the DTT. As most of their patients with positive DTTs had unimpaired coronary circulations, they conclude that positive DTTs, although falsely indicative of impaired myocardial blood supply, does have an important clinical relevance, indicating increased risk of morbidity (and, possibly, mortality) due to ventricular arrhythmias in a population of CRF patients submitted to chronic renal function replacement program

  3. Induced pluripotent stem cell-derived cardiomyocytes: boutique science or valuable arrhythmia model?

    Science.gov (United States)

    Knollmann, Björn C

    2013-03-15

    This article reviews the strengths and limitations of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) as models of cardiac arrhythmias. Specifically, the article attempts to answer the following questions: Which clinical arrhythmias can be modeled by iPSC-CM? How well can iPSC-CM model adult ventricular myocytes? What are the strengths and limitations of published iPSC-CM arrhythmia models? What new mechanistic insight has been gained? What is the evidence that would support using iPSC-CM to personalize antiarrhythmic drug therapy? The review also discusses the pros and cons of using the iPSC-CM technology for modeling specific genetic arrhythmia disorders, such as long QT syndrome, Brugada Syndrome, or Catecholaminergic Polymorphic Ventricular Tachycardia.

  4. Family and population strategies for screening and counselling of inherited cardiac arrhythmias

    NARCIS (Netherlands)

    Van Langen, I.M.; Hofman, N.; Tan, H.L.; Wilde, A.A.M.

    2004-01-01

    Family screening in inherited cardiac arrhythmias has been performed in The Netherlands since 1996, when diagnostic DNA testing in long QT syndrome (LOTS) and hypertrophic cardiomyopathy (HCM) became technically possible. In multidisciplinary outpatient academic clinics, an adjusted protocol for gen

  5. Novel energy modalities for catheter ablation of cardiac arrhythmias : Pitfalls and possibilities of potent power sources

    OpenAIRE

    Neven, K.G.E.J.

    2014-01-01

    The acceptance of catheter ablation as treatment for cardiac arrhythmias is amongst others dependent on its success rate, a high initial success rate will increase physician and patient acceptance. One of the reasons why recurrence of arrhythmia after ablation is substantial is non-transmurality of ablation lesions. Transmurality is essential for conduction block and is depending on many factors, such as tissue ablation duration, thickness of the cardiac wall, ablation technique used, cathete...

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  7. Computer assisted optimisation on non-pharmacological treatment of congestive heart failure and supraventricular arrhythmia

    OpenAIRE

    Reumann, Matthias

    2007-01-01

    Heart Failure is the most common cardiac disease worldwide; supraventricular arrhythmia the most common cardiac arrhythmia. The understanding of these diseases advances treatment options. Ablation therapy and atrial antitachycardial pacing are non-pharmacological options in the treatment of atrial fibrillation. Cardiac resynchronization therapy with biventricular pacing devices has been shown successful in patients with severe heart failure. However, an optimization or even individual therapy...

  8. Intermittent short ECG recording is more effective than 24-hour Holter ECG in detection of arrhythmias

    OpenAIRE

    Hendrikx, Tijn; Rosenqvist, Mårten; Wester, Per; Sandström, Herbert; Hörnsten, Rolf

    2014-01-01

    Background: Many patients report symptoms of palpitations or dizziness/presyncope. These patients are often referred for 24-hour Holter ECG, although the sensitivity for detecting relevant arrhythmias is comparatively low. Intermittent short ECG recording over a longer time period might be a convenient and more sensitive alternative. The objective of this study is to compare the efficacy of 24-hour Holter ECG with intermittent short ECG recording over four weeks to detect relevant arrhythmias...

  9. Clinical evaluation of a wireless ECG sensor system for arrhythmia diagnostic purposes

    OpenAIRE

    Fensli, Rune; Gundersen, Torstein; Snaprud, Tormod; Heljesen, Ole

    2013-01-01

    In a clinical study, a novel wireless electrocardiogram (ECG) recorder has been evaluated with regard to its ability to perform arrhythmia diagnostics. As the ECG recorder will detect a "non-standard" ECG signal, it has been necessary to compare those signals to "standard" ECG recording signals in order to evaluate the arrhythmia detection ability of the new system. Simultaneous recording of ECG signals from both the new wireless ECG recorder and a conventional Holter recorder was compared by...

  10. A Novel Automatic Detection System for ECG Arrhythmias Using Maximum Margin Clustering with Immune Evolutionary Algorithm

    OpenAIRE

    Bohui Zhu; Yongsheng Ding; Kuangrong Hao

    2013-01-01

    This paper presents a novel maximum margin clustering method with immune evolution (IEMMC) for automatic diagnosis of electrocardiogram (ECG) arrhythmias. This diagnostic system consists of signal processing, feature extraction, and the IEMMC algorithm for clustering of ECG arrhythmias. First, raw ECG signal is processed by an adaptive ECG filter based on wavelet transforms, and waveform of the ECG signal is detected; then, features are extracted from ECG signal to cluster different types of ...

  11. Fully parallel ANN-based arrhythmia classifier on a single-chip FPGA: FPAAC

    OpenAIRE

    ÖZDEMİR, Ahmet Turan; DANIŞMAN, Kenan

    2011-01-01

    Recognition of cardiac arrhythmias by electrocardiogram (ECG) is an important issue for diagnosis of cardiac abnormalities. Many studies on recognition of cardiac arrhythmias by ECG, using various techniques, have been performed in the past 20 years. Artificial neural networks (ANNs) are the most widely used tool in medical diagnosis systems (MDS) because of their powerful prediction characteristics. An ANN model is inspired by real biological neural networks, with a parallel structur...

  12. Detection of false arrhythmia alarms with emphasis on ventricular tachycardia.

    Science.gov (United States)

    Rodrigues, Rui; Couto, Paula

    2016-08-01

    Our approach to detecting false arrhythmia alarms in the intensive care unit breaks down into several tasks. It involves beat detection on different signals: electrocardiogram, photoplethysmogram and arterial blood pressure. The quality of each channel has to be estimated in order to evaluate the reliability of obtained beat detections. The information about the heart rate from the different channels must be integrated in order to find a final conclusion. Some alarm types require particular detectors as is the case of ventricular fibrillation. To identify false ventricular tachycardia alarms we needed to classify heart beats as normal/ventricular. For that purpose we introduce a new feature, QRS polarity type. This feature was important in order to reduce misclassification of ventricular beats: there was an improvement in the ventricular tachycardia alarm true positive rate from 69% to 81%. However, the true negative rate was reduced from 95% to 69% and our global challenge score (real-time event) dropped from 79.02 to 74.28. Our challenge algorithm achieved the third best score in the 2015 PhysioNet/CinC challenge event 1 (real time). PMID:27454934

  13. Exact coherent structures: from fluid turbulence to cardiac arrhythmias

    Science.gov (United States)

    Grigoriev, Roman; Marcotte, Christopher; Byrne, Gregory

    2014-03-01

    Ventricular fibrillation, a life threatening cardiac arrhythmia, is an example of spatiotemporally chaotic state dominated by multiple interacting spiral waves. Recent studies of weak fluid turbulence suggest that spatiotemporal chaos in general can be understood as a walk among exact unstable regular solutions (exact coherent states, ECS) of nonlinear evolution equations. Several classes of ECS are believed to play a dominant role; most typically these are equilibria and periodic orbits or relative equilibria and relative periodic orbits for systems with global continuous symmetries. Numerical methods originally developed in the context of fluid turbulence can also be applied to models of cardiac dynamics which possess translational and rotational symmetries and, indeed, allowed us to identify relative equilibria and periodic orbits describing isolated spirals with, respectively, fixed and drifting cores. In order to find regular solutions featuring multiple interacting spirals a new approach is required that takes into consideration the dynamics of slowly drifting cores associated with local, rather than global, symmetries. We describe how local symmetries can be reduced and more general types of ECS computed that dominate spiral wave chaos in models of cardiac tissue.

  14. Cardiac arrhythmia in Wilson's disease: An oversighted and overlooked entity!

    Science.gov (United States)

    Bajaj, Bhupender Kumar; Wadhwa, Ankur; Singh, Richa; Gupta, Saurabh

    2016-01-01

    Wilson's disease is a multisystem disorder which manifests with hepatic, neurological, musculoskeletal, hematological, renal, and cardiac symptoms. The hepatic and neurological manifestations often overshadow the other system involvement including cardiac symptoms and signs, which may prove fatal. We report a case of a young female who presented with progressive parkinsonian features and dystonia for around 4 months followed 2 months later by the complaint of episodes of light-headedness. She was diagnosed to have Wilson's disease based on the presence of Kayser–Fleischer ring and laboratory parameters of copper metabolism. Electrocardiography of the patient incidentally revealed 2nd degree Mobitz type-1 atrioventricular block explaining her episodes of light-headedness. She was started on penicillamine and trihexyphenidyl. The heart block improved spontaneously. Cardiac autonomic function tests including blood pressure response to standing and heart rate response to standing were observed to be normal. We review the literature on cardiac manifestations of Wilson's disease and emphasize that patients with Wilson's disease should be assessed for cardiac arrhythmia and cardiac dysfunction as these may have therapeutic and prognostic implications.

  15. Cardiac arrhythmia in Wilson's disease: An oversighted and overlooked entity!

    Science.gov (United States)

    Bajaj, Bhupender Kumar; Wadhwa, Ankur; Singh, Richa; Gupta, Saurabh

    2016-01-01

    Wilson's disease is a multisystem disorder which manifests with hepatic, neurological, musculoskeletal, hematological, renal, and cardiac symptoms. The hepatic and neurological manifestations often overshadow the other system involvement including cardiac symptoms and signs, which may prove fatal. We report a case of a young female who presented with progressive parkinsonian features and dystonia for around 4 months followed 2 months later by the complaint of episodes of light-headedness. She was diagnosed to have Wilson's disease based on the presence of Kayser–Fleischer ring and laboratory parameters of copper metabolism. Electrocardiography of the patient incidentally revealed 2nd degree Mobitz type-1 atrioventricular block explaining her episodes of light-headedness. She was started on penicillamine and trihexyphenidyl. The heart block improved spontaneously. Cardiac autonomic function tests including blood pressure response to standing and heart rate response to standing were observed to be normal. We review the literature on cardiac manifestations of Wilson's disease and emphasize that patients with Wilson's disease should be assessed for cardiac arrhythmia and cardiac dysfunction as these may have therapeutic and prognostic implications. PMID:27695244

  16. Thinking about breathing: Effects on respiratory sinus arrhythmia.

    Science.gov (United States)

    Mortola, Jacopo P; Marghescu, Domnica; Siegrist-Johnstone, Rosemarie

    2016-03-01

    Respiratory sinus arrhythmia (RSA), the increase and decrease in instantaneous heart rate (HR) with inspiration and expiration, is commonly evaluated as function of breathing frequency f. However, to the extent that RSA plays a role in the efficiency of gas exchange, it may be expected to correlate better with HR/f ('breathing specific heart rate') than with f, because the former is a better reflection of the cardio-respiratory coupling. We measured RSA breath-by-breath in 209 young men and women during spontaneous breathing and during volitional breathing under auditory cues at vastly different f. In either case, and for both genders, RSA correlated better with HR/f than with f. As HR/f increased so did RSA, in a linear manner. When compared on the basis of HR/f, RSA did not differ significantly between spontaneous and volitional breathing. It is proposed that RSA is a central mechanism that ameliorates the matching between the quasi-continuous pulmonary blood flow and the intermittent airflow, irrespective of the type of ventilatory drive (cortical or autonomic). PMID:26724603

  17. Clinical evaluation of a wireless ECG sensor system for arrhythmia diagnostic purposes.

    Science.gov (United States)

    Fensli, Rune; Gundersen, Torstein; Snaprud, Tormod; Hejlesen, Ole

    2013-06-01

    In a clinical study, a novel wireless electrocardiogram (ECG) recorder has been evaluated with regard to its ability to perform arrhythmia diagnostics. As the ECG recorder will detect a "non-standard" ECG signal, it has been necessary to compare those signals to "standard" ECG recording signals in order to evaluate the arrhythmia detection ability of the new system. Simultaneous recording of ECG signals from both the new wireless ECG recorder and a conventional Holter recorder was compared by two independent cardiology specialists with regard to signal quality for performing arrhythmia diagnosis. In addition, calculated R-R intervals from the two systems were correlated. A total number of 16 patients participated in the study. It can be considered that recorded ECG signals obtained from the wireless ECG system had an acceptable quality for arrhythmia diagnosis. Some of the patients used the wireless sensor while doing physical sport activities, and the quality of the recorded ECG signals made it possible to perform arrhythmia diagnostics even under such conditions. Consequently, this makes possible improvements in correlating arrhythmias to physical activities.

  18. Sympathetic restraint of respiratory sinus arrhythmia: implications for vagal-cardiac tone assessment in humans

    Science.gov (United States)

    Taylor, J. A.; Myers, C. W.; Halliwill, J. R.; Seidel, H.; Eckberg, D. L.

    2001-01-01

    Clinicians and experimentalists routinely estimate vagal-cardiac nerve traffic from respiratory sinus arrhythmia. However, evidence suggests that sympathetic mechanisms may also modulate respiratory sinus arrhythmia. Our study examined modulation of respiratory sinus arrhythmia by sympathetic outflow. We measured R-R interval spectral power in 10 volunteers that breathed sequentially at 13 frequencies, from 15 to 3 breaths/min, before and after beta-adrenergic blockade. We fitted changes of respiratory frequency R-R interval spectral power with a damped oscillator model: frequency-dependent oscillations with a resonant frequency, generated by driving forces and modified by damping influences. beta-Adrenergic blockade enhanced respiratory sinus arrhythmia at all frequencies (at some, fourfold). The damped oscillator model fit experimental data well (39 of 40 ramps; r = 0.86 +/- 0.02). beta-Adrenergic blockade increased respiratory sinus arrhythmia by amplifying respiration-related driving forces (P arrhythmia is mediated simply by vagal-cardiac nerve activity. These results have important implications for clinical and experimental estimation of human vagal cardiac tone.

  19. Cibenzoline versus flecainide in the prevention of paroxysmal atrial arrhythmias: a double-blind randomized study.

    Science.gov (United States)

    Babuty, D; D'Hautefeuille, B; Scheck, F; Mycinsky, C; Pruvost, P; Peraudeau, P

    1995-05-01

    In a randomized, double-blind, parallel clinical trial, the authors tested and compared flecainide and cibenzoline, a new antiarrhythmic drug, on atrial arrhythmias. Sixty-eight patients (36 men, 32 women, mean age 62.5 +/- 1.6 years) with documented symptomatic paroxysmal atrial arrhythmias (fibrillation in 56, flutter in 12) were recruited and received either cibenzoline 260 mg/day (n = 33) or flecainide 200 mg/day (n = 35). Patients were assessed with physical examination, resting ECG, 24-hour ambulatory ECG recording, two-dimensional echocardiography, and standard biologic titrations before the inclusion day, and 3 months and 6 months after the randomization day. Sixteen patients were withdrawn (7 were lost to follow-up, 7 had side effects, 2 had another medical event). Seventeen patients had documented recurrence of atrial arrhythmia (9 in the cibenzoline group, 8 in the flecainide group) during the study. The efficacy of cibenzoline and flecainide for preventing recurrence of atrial arrhythmias was not significantly different (62.5% versus 71.4%). Eleven patients complained of one or more side effects (cibenzoline, n = 6; flecainide, n = 5), justifying leaving the trial in 6 cases (cibenzoline, n = 3; flecainide, n = 3). Two ventricular proarrhythmic effects were observed. No atrial proarrhythmic effects were reported. The efficacy of cibenzoline and flecainide for preventing atrial arrhythmia is good and similar during a follow-up period of 6 months. In view of these results, cibenzoline may be administered first to prevent atrial arrhythmia. PMID:7657846

  20. 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.

  1. Exploiting periodicity to extract the atrial activity in atrial arrhythmias

    Science.gov (United States)

    Llinares, Raul; Igual, Jorge

    2011-12-01

    Atrial fibrillation disorders are one of the main arrhythmias of the elderly. The atrial and ventricular activities are decoupled during an atrial fibrillation episode, and very rapid and irregular waves replace the usual atrial P-wave in a normal sinus rhythm electrocardiogram (ECG). The estimation of these wavelets is a must for clinical analysis. We propose a new approach to this problem focused on the quasiperiodicity of these wavelets. Atrial activity is characterized by a main atrial rhythm in the interval 3-12 Hz. It enables us to establish the problem as the separation of the original sources from the instantaneous linear combination of them recorded in the ECG or the extraction of only the atrial component exploiting the quasiperiodic feature of the atrial signal. This methodology implies the previous estimation of such main atrial period. We present two algorithms that separate and extract the atrial rhythm starting from a prior estimation of the main atrial frequency. The first one is an algebraic method based on the maximization of a cost function that measures the periodicity. The other one is an adaptive algorithm that exploits the decorrelation of the atrial and other signals diagonalizing the correlation matrices at multiple lags of the period of atrial activity. The algorithms are applied successfully to synthetic and real data. In simulated ECGs, the average correlation index obtained was 0.811 and 0.847, respectively. In real ECGs, the accuracy of the results was validated using spectral and temporal parameters. The average peak frequency and spectral concentration obtained were 5.550 and 5.554 Hz and 56.3 and 54.4%, respectively, and the kurtosis was 0.266 and 0.695. For validation purposes, we compared the proposed algorithms with established methods, obtaining better results for simulated and real registers.

  2. Effect of Different Pranayamas on Respiratory Sinus Arrhythmia

    Science.gov (United States)

    Raj, Jeneth Berlin; Ramanathan, Meena; Trakroo, Madanmohan

    2016-01-01

    Introduction Respiratory Sinus Arrhythmia (RSA) is the differential change of Heart Rate (HR) in response to inspiration and expiration. This is a noninvasive sensitive index of parasympathetic cardiac control. Aim To evaluate changes in RSA by utilizing a simple and cost-effective analysis of electrocardiographic (ECG) tracings obtained during performance of four pranayama techniques. Materials and Methods Fifty two trained volunteers performed the following pranayamas with different ratios for inspiration and expiration: sukha (1:1), traditional (1:2), pranava (1:3) and savitri (2:1:2:1) and ECG was recorded while performing the techniques with rest period of 5 minutes in-between. HR was calculated and maximum HR during inspiration (Imax), minimum HR during expiration (Emin), differences between Imax and Emin (Δ), percentage differences between Imax and Emin (Δ%) and expiration: inspiration ratio (E:I) calculated by respective formulae. Statistical analysis was carried out using repeated measures of ANOVA with Tukey-Kramer multiple comparisons test. Results There were significant differences between groups in all five aspects namely: p= 0.0093 for mean Imax, p = 0.0009 for mean Emin, and p < 0.0001 for Δ HR (I-E), Δ% HR (I-E) and E:I ratio. Pranava pranayama produced the greatest changes in all five comparisons. Conclusion We suggest that further short and long term studies be undertaken with pranava pranayama in patients to further qualitatively and quantitatively evaluate inherent mechanisms of this simple technique. Addition of these cost-effective techniques to the medical armory will help patients of rhythm disorders and other cardiovascular conditions. PMID:27134863

  3. Magnesium sulphate and amiodarone prophylaxis for prevention of postoperative arrhythmia in coronary by-pass operations

    Directory of Open Access Journals (Sweden)

    Huysal Kagan

    2009-02-01

    Full Text Available Abstract Background The aim of this study was to investigate the use of prophylactic magnesium sulphate and amiodarone in treating arrhythmias that may occur following coronary bypass grafting operations. Methods The study population consisted of 192 consecutive patients who were undergoing coronary artery bypass grafting (CABG. Sixty-four patients were given 3 g of magnesium sulphate (MgSO4 [20 ml = 24.32 mEq/L Mg+2] in 100 cc of isotonic 0.9% solution over 2 hours intravenously at the following times: 12 hours prior to the operation, immediately following the operation, and on postoperative days 1, 2, and 3 (Group 1. Another group of 64 patients was given a preoperative infusion of amiodarone (1200 mg on first post-operative day (Group 2. After the operation amiodarone was administered orally at a dose of 600 mg/day. Sixty-four patients in group 3 (control group had 100 cc. isotonic 0.9% as placebo, during the same time periods. Results In the postoperative period, the magnesium values were significantly higher in Group 1 than in Group 2 for all measurements. The use of amiodarone for total arrhythmia was significantly more effective than prophylactic treatment with magnesium sulphate (p = 0.015. There was no difference between the two drugs in preventing supraventricular arrhythmia, although amiodarone significantly delayed the revealing time of atrial fibrillation (p = 0.026. Ventricular arrhythmia, in the form of ventricular extra systole, was more common in the magnesium prophylaxis group. The two groups showed no significant differences in other operative or postoperative measurements. No side effects of the drugs were observed. Conclusion Prophylactic use of magnesium sulphate and amiodarone are both effective at preventing arrhythmia that may occur following coronary by-pass operations. Magnesium sulphate should be used in prophylactic treatment since it may decrease arrhythmia at low doses. If arrhythmia should occur despite this

  4. Controversies in Cardiovascular Research: Induced pluripotent stem cell-derived cardiomyocytes – boutique science or valuable arrhythmia model?

    OpenAIRE

    Knollmann, Björn C.

    2013-01-01

    As part of the series on Controversies in Cardiovascular Research, the article reviews the strengths and limitations of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) as models of cardiac arrhythmias. Specifically, the article attempts to answer the following questions: Which clinical arrhythmias can be modeled by iPSC-CM? How well can iPSC-CM model adult ventricular myocytes? What are the strengths and limitations of published iPSC-CM arrhythmia models? What new mechanistic i...

  5. Differences in distribution of fibrosis in the ventricles underlie dominant arrhythmia vulnerability of the right ventricle in senescent mice

    OpenAIRE

    M. Noorman; van Rijen, H.V.M.; van Veen, T.A.B.; de Bakker, J.M.T.; Stein, M

    2008-01-01

    Mutations that are supposed to affect right (RV) and left ventricular (LV) electrophysiology equally, often reveal dominant conduction slowing and arrhythmia vulnerability in RV. In this study we investigated the mechanism of dominant arrhythmia vulnerability of RV in senescent mice. We performed epicardial ventricular activation mapping on adult and senescent Langendorff perfused hearts. Longitudinal and transversal conduction velocity, as well as arrhythmia inducibility were determined. Sub...

  6. Relation between QT dispersion, left ventricle systolic function and frequency of ventricular arrhythmias in coronary patients

    Directory of Open Access Journals (Sweden)

    Stoičkov Viktor

    2007-01-01

    Full Text Available Introduction QT dispersion (QTd is a measure of non-homogeneous repolarisation of the myocardium and is used as an indicator of arrhythmogenicity. Objective The aim of this study was to assess the relation between QT dispersion, left ventricle systolic function and frequency of ventricular arrhythmias in coronary patients. Method We studied 290 coronary patients, 72 with angina pectoris and 218 after myocardial infarction. Eighty-one coronary patients had frequent and complex ventricular arrhythmias (out of them 19 had ventricular tachycardia and 209 were without arrhythmias or with infrequent ventricular premature contractions (VPC≤10/h. In all patients, QT dispersion, exercise test, 24-hour Holter monitoring and echocardiographic examination were performed. Results Patients with frequent and complex ventricular arrhythmias had significantly higher values of QTd (71.8±25.5 vs 55.6±21.7 ms; p<0.001, corrected QT dispersion (QTdc: 81.3±31.5 vs. 60.3±26.1 ms; p<0.001, left ventricular end-diastolic diameter (LVEDd: 56.2±6.9 vs. 53.4±6.2 mm; p<0.001 and left ventricular end-systolic diameter (LVESd: 39.5±6.2 vs. 36.0±6.3 mm; p<0.001, and significantly lower values of left ventricular ejection fraction (LVEF: 47.7±13.9 vs. 55.9±11.6%; p<0.001 in comparison to those without arrhythmias or with infrequent VPC. Patients with VT had significantly higher values of QTd and QTdc in comparison to other patients with frequent and complex ventricular arrhythmias (83.8±17.1 vs. 69.4±26.2 ms; p<0.02 for QTd; 101.1±23.9:77.6±31.4 ms; p<0.005 for QTdc. There is a significant negative correlation of QTd and QTdc with LVEF, and a significant positive correlation of QTd and QTdc with inside dimensions of the left ventricle, in patients with frequent and complex ventricular arrhythmias. Conclusion The study demonstrated that patients with frequent and complex ventricular arrhythmias had significantly higher values of QTd and QTdc, as well as a higher

  7. Postoperative Arrhythmias after Cardiac Surgery: Incidence, Risk Factors, and Therapeutic Management

    Directory of Open Access Journals (Sweden)

    Giovanni Peretto

    2014-01-01

    Full Text Available Arrhythmias are a known complication after cardiac surgery and represent a major cause of morbidity, increased length of hospital stay, and economic costs. However, little is known about incidence, risk factors, and treatment of early postoperative arrhythmias. Both tachyarrhythmias and bradyarrhythmias can present in the postoperative period. In this setting, atrial fibrillation is the most common heart rhythm disorder. Postoperative atrial fibrillation is often self-limiting, but it may require anticoagulation therapy and either a rate or rhythm control strategy. However, ventricular arrhythmias and conduction disturbances can also occur. Sustained ventricular arrhythmias in the recovery period after cardiac surgery may warrant acute treatment and long-term preventive strategy in the absence of reversible causes. Transient bradyarrhythmias may be managed with temporary pacing wires placed at surgery, but significant and persistent atrioventricular block or sinus node dysfunction can occur with the need for permanent pacing. We provide a complete and updated review about mechanisms, risk factors, and treatment strategies for the main postoperative arrhythmias.

  8. Arrhythmia Management in the Elderly-Implanted Cardioverter Defibrillators and Prevention of Sudden Death.

    Science.gov (United States)

    Manian, Usha; Gula, Lorne J

    2016-09-01

    We present an overview of arrhythmia management in elderly patients as it pertains to implantable cardioverter defibrillator (ICD) therapy and prevention of sudden death. Treatment of arrhythmia in elderly patients is fraught with challenges pertaining to goals of care and patient frailty. With an ever increasing amount of technology available, realistic expectations of therapy need to balance quality and quantity of life. The ICD is an important treatment option for selected patients at risk of ventricular arrhythmia and sudden cardiac death. However, the incidence of sudden death as a percentage of all-cause mortality decreases with age. Studies have reported that 20% of elderly patients might die within 1 year of an episode of life-threatening ventricular arrhythmia, but most because of nonarrhythmic causes. This illustrates the 'sudden cardiac death paradox,' with a great proportion of death in elderly patients, even those at risk for ventricular arrhythmias, attributable to medical conditions that cannot be addressed by an ICD. We discuss current practices in ICD therapy in elderly patients, existing evidence from registries and clinical trials, approaches to risk stratification, and important ethical considerations. Although the decision on whether ICD insertion is appropriate in the elderly population remains an area of uncertainty from an evidence-based and ethical perspective, we offer insight on potential clinical and research strategies for this growing population. PMID:27568872

  9. Postoperative arrhythmias after cardiac surgery: incidence, risk factors, and therapeutic management.

    Science.gov (United States)

    Peretto, Giovanni; Durante, Alessandro; Limite, Luca Rosario; Cianflone, Domenico

    2014-01-01

    Arrhythmias are a known complication after cardiac surgery and represent a major cause of morbidity, increased length of hospital stay, and economic costs. However, little is known about incidence, risk factors, and treatment of early postoperative arrhythmias. Both tachyarrhythmias and bradyarrhythmias can present in the postoperative period. In this setting, atrial fibrillation is the most common heart rhythm disorder. Postoperative atrial fibrillation is often self-limiting, but it may require anticoagulation therapy and either a rate or rhythm control strategy. However, ventricular arrhythmias and conduction disturbances can also occur. Sustained ventricular arrhythmias in the recovery period after cardiac surgery may warrant acute treatment and long-term preventive strategy in the absence of reversible causes. Transient bradyarrhythmias may be managed with temporary pacing wires placed at surgery, but significant and persistent atrioventricular block or sinus node dysfunction can occur with the need for permanent pacing. We provide a complete and updated review about mechanisms, risk factors, and treatment strategies for the main postoperative arrhythmias. PMID:24511410

  10. The susceptibility of ventricular arrhythmia to aconitine in conscious Lyon hypertensive rats

    Institute of Scientific and Technical Information of China (English)

    Min LI; Jin WANG; He-hui XIE; Fu-ming SHEN; Ding-feng SU

    2007-01-01

    Aim: The present work was designed to investigate the relationship between hemodynamic parameters and the susceptibility of ventricular arrhythmia to aconitine in conscious Lyon hypertensive rats (LH). Methods: Male LH and Lyon low blood pressure rats (LL) were used. After the determination of baroreflex sensitivity (BRS), ventricular arrhythmia was induced by aconitine infusion inconscious rats. Blood pressure (BP) was recorded during the period of infusion. Results: Compared with the LL rats, the LH rats possessed significantly higher BP, blood pressure variability and lower BRS. The threshold of aconitine required for ventricular fibrillation and cardiac arrest in the LH rats were significantly lower than those in the LL rats. It was found that all the hemodynamic parameters studied were not correlated with the tl~eshold of aconitine required for arrhythmia, with the exception of BRS, which was positively related to the threshold of aconitine required for ventricular premature beat. Conclusion: The LH rats possessed greater susceptibility to aconitine-induced ventricular arrhythmias when compared to the LL rats. This greater susceptibility could not be attributed to anyone of the hemodynamic parameters alone studied in the LH rats. It is proposed that various hypertension-associated abnormalities, including the abnormal hemodynamics, may co-contribute to this vulnerability to ventricular arrhythmias.

  11. 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

  12. Ventricular arrhythmias in patients of atrial fibrillation treated with Flecainide: A case report

    Directory of Open Access Journals (Sweden)

    Barman M, Djamel B

    2014-07-01

    Full Text Available Purpose: Flecainide is a class 1C antiarrhythmic drug, especially used for the management of supraventricular arrhythmia. Flecainide also has a recognized proarrhythmic effect in all age groups of adult patients treated for ventricular tachycardia. It is used to treat a variety of cardiac arrhythmias including paroxysmal fibrillation, Paroxysmal Supraventricular tachycardia and ventricular tachycardia. Flecainide works by regulating the flow of sodium in the heart, causing prolongation of the cardiac action potential. The proarrhythmic effects however noted are not widely reported. Case report: We report a case of paroxysmal atrial fibrillation with structurally normal heart who was treated with oral Flecainide. Despite subjective improvement and no adverse events [QTc prolongation] a repeat holter detected him to have multiple short non sustained ventricular arrhythmias. Results: Development of ventricular arrhythmias, salvos &non sustained ventricular tachycardia after a month of initiation of oral Flecainide detected by 24 hours ECG holter lead to discontinuation of Flecainide and subsequent early electro physiological studies and successful ablation. Conclusion: Initiation of oral Flecainide in a case of atrial fibrillation with subjective improvement and regular ECG monitoring, no QTc prolongation can still lead to development of dangerous ventricular arrhythmias. A cautious approach and thorough investigations and follow up are recommended.

  13. Electrical alternans during rest and exercise as predictors of vulnerability to ventricular arrhythmias

    Science.gov (United States)

    Estes, N. A. 3rd; Michaud, G.; Zipes, D. P.; El-Sherif, N.; Venditti, F. J.; Rosenbaum, D. S.; Albrecht, P.; Wang, P. J.; Cohen, R. J.

    1997-01-01

    This investigation was performed to evaluate the feasibility of detecting repolarization alternans with the heart rate elevated with a bicycle exercise protocol. Sensitive spectral signal-processing techniques are able to detect beat-to-beat alternation of the amplitude of the T wave, which is not visible on standard electrocardiogram. Previous animal and human investigations using atrial or ventricular pacing have demonstrated that T-wave alternans is a marker of vulnerability to ventricular arrhythmias. Using a spectral analysis technique incorporating noise reduction signal-processing software, we evaluated electrical alternans at rest and with the heart rate elevated during a bicycle exercise protocol. In this study we defined optimal criteria for electrical alternans to separate patients from those without inducible arrhythmias. Alternans and signal-averaged electrocardiographic results were compared with the results of vulnerability to ventricular arrhythmias as defined by induction of sustained ventricular tachycardia or fibrillation at electrophysiologic evaluation. In 27 patients alternans recorded at rest and with exercise had a sensitivity of 89%, specificity of 75%, and overall clinical accuracy of 80% (p <0.003). In this patient population the signal-averaged electrocardiogram was not a significant predictor of arrhythmia vulnerability. This is the first study to report that repolarization alternans can be detected with heart rate elevated with a bicycle exercise protocol. Alternans measured using this technique is an accurate predictor of arrhythmia inducibility.

  14. Calcium and voltage imaging in arrhythmia models by high-speed microscopy

    Science.gov (United States)

    de Mauro, C.; Cecchetti, C. A.; Alfieri, D.; Borile, G.; Urbani, A.; Mongillo, M.; Pavone, F. S.

    2014-03-01

    Alterations in intracellular cardiomyocyte calcium handling have a key role in initiating and sustaining arrhythmias. Arrhythmogenic calcium leak from sarcoplasmic reticulum (SR) can be attributed to all means by which calcium exits the SR store in an abnormal fashion. Abnormal SR calcium exit maymanifest as intracellular Ca2+ sparks and/or Ca2+ waves. Ca2+ signaling in arrhythmogenesis has been mainly studied in isolated cardiomyocytes and given that the extracellular matrix influences both Ca2+ and membrane potential dynamics in the intact heart and underlies environmentally mediated changes, understanding how Ca2+ and voltage are regulated in the intact heart will represent a tremendous advancement in the understanding of arrhythmogenic mechanisms. Using novel high-speed multiphoton microscopy techinques, such as multispot and random access, we investigated animal models with inherited and acquired arrhythmias to assess the role of Ca2+ and voltage signals as arrhythmia triggers in cell and subcellular components of the intact heart and correlate these with electrophysiology.

  15. Method and apparatus for the guided ablative therapy of fast ventricular arrhythmia

    Science.gov (United States)

    Cohen, Richard J. (Inventor); Barley, Maya (Inventor)

    2010-01-01

    Method and apparatus for guiding ablative therapy of abnormal biological electrical excitation. The excitation from the previous excitatory wave is significant at the beginning of the next excitation. In particular, it is designed for treatment of fast cardiac arrhythmias. Electrical signals are acquired from recording electrodes, and an inverse dipole method is used to identify the site of origin of an arrhythmia. The location of the tip of an ablation catheter is similarly localized from signals acquired from the recording electrodes while electrical pacing energy is delivered to the tip of the catheter close to or in contact with the cardiac tissue. The catheter tip is then guided to the site of origin of the arrhythmia, and ablative radio frequency energy is delivered to its tip to ablate the site.

  16. Arrhythmia risk stratification of patients after myocardial infarction using personalized heart models.

    Science.gov (United States)

    Arevalo, Hermenegild J; Vadakkumpadan, Fijoy; Guallar, Eliseo; Jebb, Alexander; Malamas, Peter; Wu, Katherine C; Trayanova, Natalia A

    2016-01-01

    Sudden cardiac death (SCD) from arrhythmias is a leading cause of mortality. For patients at high SCD risk, prophylactic insertion of implantable cardioverter defibrillators (ICDs) reduces mortality. Current approaches to identify patients at risk for arrhythmia are, however, of low sensitivity and specificity, which results in a low rate of appropriate ICD therapy. Here, we develop a personalized approach to assess SCD risk in post-infarction patients based on cardiac imaging and computational modelling. We construct personalized three-dimensional computer models of post-infarction hearts from patients' clinical magnetic resonance imaging data and assess the propensity of each model to develop arrhythmia. In a proof-of-concept retrospective study, the virtual heart test significantly outperformed several existing clinical metrics in predicting future arrhythmic events. The robust and non-invasive personalized virtual heart risk assessment may have the potential to prevent SCD and avoid unnecessary ICD implantations. PMID:27164184

  17. Relationship between Fibrosis and Ventricular Arrhythmias in Chagas Heart Disease Without Ventricular Dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Tassi, Eduardo Marinho, E-mail: etassi@ibest.com.br [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Continentino, Marcelo Abramoff [Hospital Frei Galvão, Guaratinguetá, SP (Brazil); Nascimento, Emília Matos do; Pereira, Basílio de Bragança [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Coppe - Instituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa de Engenharia - UFRJ, Rio de Janeiro, RJ (Brazil); Pedrosa, Roberto Coury [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

    2014-05-15

    Patients with Chagas disease and segmental wall motion abnormality (SWMA) have worse prognosis independent of left ventricular ejection fraction (LVEF). Cardiac magnetic resonance (CMR) is currently the best method to detect SWMA and to assess fibrosis. To quantify fibrosis by using late gadolinium enhancement CMR in patients with Chagas disease and preserved or minimally impaired ventricular function (> 45%), and to detect patterns of dependence between fibrosis, SWMA and LVEF in the presence of ventricular arrhythmia. Electrocardiogram, treadmill exercise test, Holter and CMR were carried out in 61 patients, who were divided into three groups as follows: (1) normal electrocardiogram and CMR without SWMA; (2) abnormal electrocardiogram and CMR without SWMA; (3) CMR with SWMA independently of electrocardiogram. The number of patients with ventricular arrhythmia in relation to the total of patients, the percentage of fibrosis, and the LVEF were, respectively: Group 1, 4/26, 0.74% and 74.34%; Group 2, 4/16, 3.96% and 68.5%; and Group 3, 11/19, 14.07% and 55.59%. Ventricular arrhythmia was found in 31.1% of the patients. Those with and without ventricular arrhythmia had mean LVEF of 59.87% and 70.18%, respectively, and fibrosis percentage of 11.03% and 3.01%, respectively. Of the variables SWMA, groups, age, LVEF and fibrosis, only the latter was significant for the presence of ventricular arrhythmia, with a cutoff point of 11.78% for fibrosis mass (p < 0.001). Even in patients with Chagas disease and preserved or minimally impaired ventricular function, electrical instability can be present. Regarding the presence of ventricular arrhythmia, fibrosis is the most important variable, its amount being proportional to the complexity of the groups.

  18. Arrhythmia recognition and classification using combined linear and nonlinear features of ECG signals.

    Science.gov (United States)

    Elhaj, Fatin A; Salim, Naomie; Harris, Arief R; Swee, Tan Tian; Ahmed, Taqwa

    2016-04-01

    Arrhythmia is a cardiac condition caused by abnormal electrical activity of the heart, and an electrocardiogram (ECG) is the non-invasive method used to detect arrhythmias or heart abnormalities. Due to the presence of noise, the non-stationary nature of the ECG signal (i.e. the changing morphology of the ECG signal with respect to time) and the irregularity of the heartbeat, physicians face difficulties in the diagnosis of arrhythmias. The computer-aided analysis of ECG results assists physicians to detect cardiovascular diseases. The development of many existing arrhythmia systems has depended on the findings from linear experiments on ECG data which achieve high performance on noise-free data. However, nonlinear experiments characterize the ECG signal more effectively sense, extract hidden information in the ECG signal, and achieve good performance under noisy conditions. This paper investigates the representation ability of linear and nonlinear features and proposes a combination of such features in order to improve the classification of ECG data. In this study, five types of beat classes of arrhythmia as recommended by the Association for Advancement of Medical Instrumentation are analyzed: non-ectopic beats (N), supra-ventricular ectopic beats (S), ventricular ectopic beats (V), fusion beats (F) and unclassifiable and paced beats (U). The characterization ability of nonlinear features such as high order statistics and cumulants and nonlinear feature reduction methods such as independent component analysis are combined with linear features, namely, the principal component analysis of discrete wavelet transform coefficients. The features are tested for their ability to differentiate different classes of data using different classifiers, namely, the support vector machine and neural network methods with tenfold cross-validation. Our proposed method is able to classify the N, S, V, F and U arrhythmia classes with high accuracy (98.91%) using a combined support

  19. Risk of arrhythmia induced by psychotropic medications: a proposal for clinical management.

    Science.gov (United States)

    Fanoe, Søren; Kristensen, Diana; Fink-Jensen, Anders; Jensen, Henrik Kjærulf; Toft, Egon; Nielsen, Jimmi; Videbech, Poul; Pehrson, Steen; Bundgaard, Henning

    2014-05-21

    Several drugs used in the treatment of mental diseases are associated with an increased risk of sudden cardiac death (SCD). A general cause-relationship between the intake of these drugs and SCD is unattainable, but numerous case reports of drug-induced malignant arrhythmia and epidemiological studies, associating the use of specific drugs with SCD, strongly support the presence of an increased risk. Whereas the absolute risk of drug-induced life-threatening arrhythmia may be relatively low, even small increments in risk of SCD may have a major health impact considering that millions of patients are treated with psychotropics. In subgroups of pre-disposed patients, e.g. patients with cardiac diseases or other co-morbidities, the elderly or patients treated with other negatively interacting drugs, the absolute risk of drug-induced arrhythmia may be considerable. On the other hand, several of the major mental disorders are associated with a large risk of suicide if untreated. The observed risk of malignant arrhythmia associated with treatment with psychotropic drugs calls for clinical guidelines integrating the risk of the individual drug and other potentially interacting risk factors. In this review, data from various authorities on the risk of arrhythmia associated with psychotropic medications were weighted and categorized into three risk categories. Additionally, we suggest a clinically applicable algorithm to reduce the risk of malignant arrhythmia in patients to be treated with psychotropic medications. The algorithm integrates the risk categories of the individual drugs and pre-disposing risk factors and suggests a prudent follow-up for patients with an increased risk. We believe this clinically manageable guideline might improve safety in the many and rapidly increasing number of patients on psychotropic drugs.

  20. Effects of short-term administration of estradiol on reperfusion arrhythmias in rats of different ages

    Energy Technology Data Exchange (ETDEWEB)

    Savergnini, S.Q.; Reis, A.M. [Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Santos, R.A.S. [1Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Santos, P.E.B. [Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Ferreira, A.J. [Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Almeida, A.P. [Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil)

    2012-11-01

    Little is known about age-related differences in short-term effects of estradiol on ischemia-reperfusion (I/R) insults. The present study was designed to evaluate the effects of short-term treatment with estradiol on reperfusion arrhythmias in isolated hearts of 6-7-week-old and 12-14-month-old female rats. Wistar rats were sham-operated, ovariectomized and treated with vehicle or ovariectomized and treated with 17β-estradiol (E{sub 2}; 5 µg·100 g{sup −1}·day{sup −1}) for 4 days. Hearts were perfused by the Langendorff technique. Reperfusion arrhythmias, i.e., ventricular tachycardia and/or ventricular fibrillation, were induced by 15 min of left coronary artery ligation and 30 min of reperfusion. The duration and incidence of I/R arrhythmias were significantly higher in young rats compared to middle-aged rats (arrhythmia severity index: 9.4 ± 1.0 vs 3.0 ± 0.3 arbitrary units, respectively, P < 0.05). In addition, middle-aged rats showed lower heart rate, systolic tension and coronary flow. Four-day E{sub 2} treatment caused an increase in uterine weight. Although E{sub 2} administration had no significant effect on the duration of I/R arrhythmias in middle-aged rats, it induced a marked reduction in the rhythm disturbances of young rats accompanied by a decrease in heart rate of isolated hearts. Also, this reduction was associated with an increase in QT interval. No significant changes were observed in the QT interval of middle-aged E{sub 2}-treated rats. These data demonstrate that short-term estradiol treatment protects against I/R arrhythmias in hearts of young female rats. The anti-arrhythmogenic effect of estradiol might be related to a lengthening of the QT interval.

  1. QT dispersion on ECG Holter monitoring and risk of ventricular arrhythmias in patients with dilated cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Polyxeni Garyfallidis

    2010-05-01

    Full Text Available Background. QT dispersion (QTd is increased in patients with dilated cardiomyopathy. Increased QTd has been associated with the risk of sudden death. We studied: a the relation between QTd on 12-lead ECG and QTd-ECG Holter; b the relation between QTd apex (QTda and QTd end (QTde on ECG Holter and the risk of ventricular arrhythmias in patients with dilated cardiomyopathy. Methods and Results. 65 patients with dilated cardiomyopathy (33 idiopathic and 32 post-ischemic etiology; NYHA II-III were studied. We divided the patients into: Group A -patients with not-sustained ventricular arrhythmias-; and Group B -patients without arrhythmias-. A significant direct correlation between QTd calculated from 12-lead ECG and from ECG Holter was found in all patients. QTda/24h was not significantly different in the two groups (Gr.A 59.9±7.8 msec vs Gr.B 53.6±8.4 msec p=ns while QTde/24h was significantly higher in Group A (Gr.A 81.9±5.9 msec vs Gr.B 44.5±6.8 msec; p<0.005. In post-ischemic etiology (32 pts; 17 with arrhythmias the correlation between QTde/24h and ventricular arrhythmias was confirmed (Gr.A 81.4±7.8 msec vs Gr.B 42.6±6.2 msec p<0.002. Conclusions. ECG Holter recordings can evaluate QTd as well as the QTd on 12-lead ECG. An increased QTde/24h seems to be correlated with the occurence of ventricular arrhythmias in patients with dilated cardiomyopathy and can then be a useful tool to select patients at high risk for sudden death.

  2. Risk of Ventricular Arrhythmia with Citalopram and Escitalopram: A Population-Based Study

    Science.gov (United States)

    Qirjazi, Elena; McArthur, Eric; Nash, Danielle M.; Dixon, Stephanie N.; Weir, Matthew A.; Vasudev, Akshya; Jandoc, Racquel; Gula, Lorne J.; Oliver, Matthew J.; Wald, Ron; Garg, Amit X.

    2016-01-01

    Background The risk of ventricular arrhythmia with citalopram and escitalopram is controversial. In this study we investigated the association between these two drugs and the risk of ventricular arrhythmia. Methods We conducted a population-based retrospective cohort study of older adults (mean age 76 years) from 2002 to 2012 in Ontario, Canada, newly prescribed citalopram (n = 137 701) or escitalopram (n = 38 436), compared to those prescribed referent antidepressants sertraline or paroxetine (n = 96 620). After inverse probability of treatment weighting using a propensity score, the baseline characteristics of the comparison groups were similar. The primary outcome was a hospital encounter with ventricular arrhythmia within 90 days of a new prescription, assessed using hospital diagnostic codes. The secondary outcome was all-cause mortality within 90 days. Results Citalopram was associated with a higher risk of a hospital encounter with ventricular arrhythmia compared with referent antidepressants (0.06% vs. 0.04%, relative risk [RR] 1.53, 95% confidence intervals [CI]1.03 to 2.29), and a higher risk of mortality (3.49% vs. 3.12%, RR 1.12, 95% CI 1.06 to 1.18). Escitalopram was not associated with a higher risk of ventricular arrhythmia compared with the referent antidepressants (0.03% vs. 0.04%, RR 0.84, 95% CI 0.42 to 1.68), but was associated with a higher risk of mortality (2.86% vs. 2.63%, RR 1.09, 95% CI 1.01 to 1.18). Conclusion Among older adults, initiation of citalopram compared to two referent antidepressants was associated with a small but statistically significant increase in the 90-day risk of a hospital encounter for ventricular arrhythmia. PMID:27513855

  3. Characterization of antiarrhythmic drugs by alternating current induced arrhythmias in isolated heart tissues.

    Science.gov (United States)

    Borchard, U; Bösken, R; Greeff, K

    1982-04-01

    A new method for inducing arrhythmias or asystolia by the application of a 50 HZ alternating current (ac) to electrically driven heart preparations has been developed and applied to isolated left atria and right ventricular papillary muscles of the guinea-pig. An increase in driving frequency from 1 to 3 HZ effects a significant reduction of the threshold of ac-arrhythmia in guinea-pig papillary muscles but no change in atria. A decrease in temperature from 31 degrees C to 25 degrees C and an increase in [Ca2+]0 from 1.25 to 5 mmol/l elevates threshold for ac-arrhythmia and -asystolia. The fast sodium channel inhibitors quinidine, carticaine and benzylamino-5,6-dihydro-8,9-dimethoxy-imidazo-5,1-a-isoquinoline hydrochloride (HE-36) increase threshold of ac-arrhythmia in left atria and papillary muscles, whereas the slow channel inhibitor verapamil is ineffective in concentrations up to 6 mumol/l. Threshold of ac-arrhythmia is elevated by quinidine predominantly in papillary muscles. Carticaine and HE-36 are effective in left atria and papillary muscles to almost the same extent. Threshold of ac-asystolia is increased mainly in papillary muscles by quinidine and HE-36; carticaine produces a similar increase in left atria and papillary muscles. Verapamil even leads to a decrease in threshold predominantly in papillary muscles. It is concluded that model arrhythmias induced by alternating current are brought about mainly by an increase in Na+-conductance of cardiac cell membranes. The negative chronotropic potency in right atria occurs in the sequence verapamil greater than quinidine greater than carticane approximately HE-36. The negative inotropic potency in papillary muscle occurs in the same sequence but HE-36 increases force of contraction.

  4. Effects of short-term administration of estradiol on reperfusion arrhythmias in rats of different ages

    International Nuclear Information System (INIS)

    Little is known about age-related differences in short-term effects of estradiol on ischemia-reperfusion (I/R) insults. The present study was designed to evaluate the effects of short-term treatment with estradiol on reperfusion arrhythmias in isolated hearts of 6-7-week-old and 12-14-month-old female rats. Wistar rats were sham-operated, ovariectomized and treated with vehicle or ovariectomized and treated with 17β-estradiol (E2; 5 µg·100 g−1·day−1) for 4 days. Hearts were perfused by the Langendorff technique. Reperfusion arrhythmias, i.e., ventricular tachycardia and/or ventricular fibrillation, were induced by 15 min of left coronary artery ligation and 30 min of reperfusion. The duration and incidence of I/R arrhythmias were significantly higher in young rats compared to middle-aged rats (arrhythmia severity index: 9.4 ± 1.0 vs 3.0 ± 0.3 arbitrary units, respectively, P < 0.05). In addition, middle-aged rats showed lower heart rate, systolic tension and coronary flow. Four-day E2 treatment caused an increase in uterine weight. Although E2 administration had no significant effect on the duration of I/R arrhythmias in middle-aged rats, it induced a marked reduction in the rhythm disturbances of young rats accompanied by a decrease in heart rate of isolated hearts. Also, this reduction was associated with an increase in QT interval. No significant changes were observed in the QT interval of middle-aged E2-treated rats. These data demonstrate that short-term estradiol treatment protects against I/R arrhythmias in hearts of young female rats. The anti-arrhythmogenic effect of estradiol might be related to a lengthening of the QT interval

  5. The role of viruses, inflammation and myocardial macrophages in the development of idiopathic arrhythmia

    Science.gov (United States)

    Rebenkova, M.; Gombozhapova, A.; Shurupov, V.; Rogovskaya, Yu.; Botalov, R.; Ryabov, V.; Popov, S.; Karpov, R.

    2015-11-01

    We studied viral antigens, inflammation, and macrophages in the endomyocardial biopsies of patients with idiopathic arrhythmias. Immunohistological study was performed to identify the antigens of cardiotropic viruses and the types of lymphocytes and macrophages. We observed the presence of viral antigens in the myocardium of patients with and without histological criteria of myocarditis. Heart failure and ventricular arrhythmias were associated with small focal infiltration of the myocardium with macrophages. The presence of viral antigens in the myocardium was associated with fewer number of myocardial M2 macrophages. Severity of myocardial interstitial fibrosis correlated with small-focal infiltration of M2 macrophages.

  6. Molecular genetic diagnostics of the cause of ventricular arrhythmias in children

    DEFF Research Database (Denmark)

    Brøndberg, Anders Krogh; Bjerre, Jesper Vandborg; Nielsen, Jens Cosedis;

    2015-01-01

    Andersen-Tawil syndrome (ATS) is a rare hereditary multi--system disorder consisting of a triad of symptoms, ventricular arrhythmias, periodic paralysis and dysmorphic features. The syndrome is associated with a loss of function mutation in the gene KCNJ2, which encodes the Kir2.1 inward rectifier...... potassium channel. We represent a case story of a 15-year-old girl who had unexplained arrhythmias for six years. Molecular genetic screening with a 75-heart-panel revealed a pathogenic KCNJ2 missense mutation. The patient was diagnosed with ATS....

  7. Actual expertise issues of professional suitability of patients with highly curable heart arrhythmias

    Directory of Open Access Journals (Sweden)

    Krainyukov P.E.

    2015-09-01

    Conclusion. The concept of highly curable heart arrhythmia is introduced. A significant proportion of patients with these arrhythmias are young and of working age, they do not have organic heart disease. High efficiency of RFA for paroxysmal disorders of rhythm, small percentage of complications and recurrences, fast professional and social rehabilitation of these patients allow to revise the existing categories of fitness in respect of persons who underwent RFA. Follow-up medical examination including endo-EFI and subsequent medical examination to determine the category of fitness for military service should be carried out not earlier than 3 months after RFA.

  8. Design and implementation of a simple portable biomedical electronic device to diagnose cardiac arrhythmias

    Directory of Open Access Journals (Sweden)

    H. Azucena

    2015-06-01

    Full Text Available This paper presents the development of a simple portable biomedical electronic device to detect cardiac arrhythmias in humans. It identifies three main parts: an electrocardiograph, a device for data communication and a personal computer with software for diagnosis. The system performs automatic diagnosis of cardiac arrhythmias by comparing the patient’s electrocardiogram with those contained in a database stored in a personal computer. The biomedical device performance is satisfactory and it demonstrated its usefulness even in the absence of medical specialist in cardiology.

  9. Anti-HERG activity and the risk of drug-induced arrhythmias and sudden death

    DEFF Research Database (Denmark)

    De Bruin, M L; Pettersson, M; Meyboom, R H B;

    2005-01-01

    AIMS: Drug-induced QTc-prolongation, resulting from inhibition of HERG potassium channels may lead to serious ventricular arrhythmias and sudden death. We studied the quantitative anti-HERG activity of pro-arrhythmic drugs as a risk factor for this outcome in day-to-day practice. METHODS AND RESU...... with the risk of reports of serious ventricular arrhythmias and sudden death in the WHO-UMC database. These findings are in support of the value of pre-clinical HERG testing to predict pro-arrhythmic effects of medicines....

  10. The Relationship between Left Atrial Volume and Ventricular Arrhythmias in the Patients with Dilated Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Abdullah Kaplan

    2014-03-01

    Full Text Available Background:: The present study aimed to investigate the relationship between Left Atrial Volume (LAV, a marker of diastolic dysfunction, and the frequency of malignant ventricular arrhythmia in the patients with left ventricular dysfunction and a previously implanted Implantable Cardioverter Defibrillator (ICD device. Methods:: This cross-sectional study was conducted on 32 patients with ischemic or idiopathic dilated cardiomyopathy, each having had an ICD device implanted at least 1 year beforehand. The ventricular arrhythmia episodes which were detected and stored by the device were retrieved and evaluated. In addition to routine echocardiographic measurements, all the patients had their LAV and LAV indexes calculated. After all, student’s t-test, Mann-Whitney U test, and Pearson correlation were used to analyze the data. Besides, P value < 0.05 was considered as statistically significant. Results:: This study was conducted on 4 female and 28 male patients with the mean age of 58.41 ± 9.97 years. Among the study patients, 21 had at least one previous myocardial infarction. In addition, 17 patients had experienced sustained VT or VF within the last year. No significant difference was found between the patients with and without malignant ventricular arrhythmias (sustained VT or VF regarding LAV (17 patients with arrhythmia (68 + 23.39 mL vs. 15 patients without arrhythmia (55.13 ± 20.41 mL; P = 0.100. However, the LAV index was significantly higher in the patients with arrhythmia compared to those without arrhythmia (39.27 ± 12.19 mL / m2 vs. 25.18 ± 7.45 mL / m2; P = 0.004. Both LAV (73.33 ± 17.64 mL and 57.52 ± 23.15 mL, respectively; P = 0.040 and LAV index (40.86 ± 8.47 mL / m2 and 28.20 ± 11.77 mL / m2, respectively; P = 0.010 were significantly greater in the patients with ICD shock therapy within the last year compared to the others. However, both groups were similar regarding Left Ventricular Volume (LVV, LVV index, and

  11. Analysis of electrolyte abnormalities and the mechanisms leading to arrhythmias in heart failure. A literature review.

    Science.gov (United States)

    Urso, C; Canino, B; Brucculeri, S; Firenze, A; Caimi, G

    2016-01-01

    About 50% of deaths from heart failure (HF) are sudden, presumably referable to arrhythmias. Electrolyte and acid-base abnormalities are a frequent and potentially dangerous complication in HF patients. Their incidence is almost always correlated with the severity of cardiac dysfunction; furthermore leading to arrhythmias, these imbalances are associated with a poor prognosis. The frequency of ventricular ectopic beats and sudden cardiac death correlate with both plasma and whole body levels of potassium, especially in alkalemia. The early recognition of these alterations and the knowledge of the pathophysiological mechanisms are useful for the management of these HF patients.

  12. Codevelopment of externalizing and internalizing symptoms in middle to late childhood: Sex, baseline respiratory sinus arrhythmia, and respiratory sinus arrhythmia reactivity as predictors

    OpenAIRE

    Hinnant, J. Benjamin; El-Sheikh, Mona

    2013-01-01

    We investigated the roles of sex and respiratory sinus arrhythmia (RSA), an index of autonomic parasympathetic nervous system activity, as predictors of codeveloping externalizing and internalizing symptoms in middle childhood. We expected that sex, baseline RSA (RSA-B), and RSA reactivity (RSA-R) to two types of tasks would interact to differentiate co-occurring trajectories of symptoms. We tested these hypotheses by combining longitudinal data from two independent samples (n = 390; 210 girl...

  13. Coronary flow and reactivity, but not arrhythmia vulnerability, are affected by cardioplegia during cardiopulmonary bypass in piglets

    DEFF Research Database (Denmark)

    Liuba, Petru; Johansson, Sune; Pesonen, Erkki;

    2013-01-01

    and receptor-related flow regulation, whereas arrhythmia vulnerability appeared to be comparable with that in non-cardioplegia group. In this study, preconditioning with cyclosporine had no detectable protective effect on coronary circulation or arrhythmia vulnerability after CPB. © 2013 Liuba et al.; licensee...

  14. Over-phosphorylation of FKBP12.6, phospholamban,relating to exacerbation of cardiac arrhythmias and failure

    Institute of Scientific and Technical Information of China (English)

    De-zaiDAI

    2004-01-01

    AIM: Cardiac arrhythmias occur severely in diseased and failing hearts and remain an important cause of mortality in cardiovascular disorders. It was intended to explore mechanisms of abnormal ion channels underlying cardiac arrhythmias and failure and in responses to drug interventions. METHODS: Chronic infarction plus isoproterenol (ISO) medication or L-thyroxin (THY) repetitive medication promote cardiac remodeling and exaggerated

  15. Relationship of ventricular arrhythmias to the angiographically and scintigraphically estimated extent of ventricular damage late after myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Huikuri, H.V.; Korhonen, U.R.; Linnaluoto, M.K.; Takkunen, J.T.

    1987-03-01

    In order to study the quantitative relationship of ventricular arrhythmias to myocardial damage and ischemia, 61 patients with a previous myocardial infarction (at least 6 months previously) were studied by 24-hour ambulatory ECG monitoring, cardiac catheterization, and thallium-201 scintigraphy. Thirty-five patients (57%) had no ectopic beats or only infrequent, unifocal ones and 26 patients (43%) had complex ventricular arrhythmias. Left ventricular function was lower in the latter, but the number of diseased vessels did not differ in the two groups. The reduction of thallium activity in the infarct area was more marked in patients with complex arrhythmias. Multiple thallium defects were not more common in arrhythmia patients, however. These data support the view that complex ventricular arrhythmias are more closely related to the severity of ventricular damage than the presence of myocardial ischemia remote to the area of previous infarction.

  16. N-3 fatty acids from fish and markers of cardiac arrhythmia

    NARCIS (Netherlands)

    Geelen, A.

    2004-01-01

    N‑3 fatty acids from fish may protect against heart disease mortality by preventing fatal arrhythmias. The objective of this thesis was to investigate whether this possible antiarrhythmic effect of n-3 fatty acids is supported by short-term effects on electrophysiological markers. We performed two h

  17. Changes underlying arrhythmia in the transgenic heart overexpressing Refsum disease gene-associated protein.

    Science.gov (United States)

    Koh, Jeong Tae; Jeong, Byung Chul; Kim, Jae Ha; Ahn, Young Keun; Lee, Hyang Sim; Baik, Yung Hong; Kim, Kyung Keun

    2004-01-01

    Previously, we identified a novel neuron-specific protein (PAHX-AP1) that binds to Refsum disease gene product (PAHX), and we developed transgenic (TG) mice that overexpress heart-targeted PAHX-AP1. These mice have atrial tachycardia and increased susceptibility to aconitine-induced arrhythmia. This study was undertaken to elucidate the possible changes in ion channels underlying the susceptibility to arrhythmia in these mice. RT-PCR analyses revealed that the cardiac expression of adrenergic beta(1)-receptor (ADRB1) was markedly lower, whereas voltage-gated potassium channel expression (Kv2.1) was higher in PAHX-AP1 TG mice compared with non-TG mice. However, the expression of voltage-sensitive sodium and calcium channels, and muscarinic receptor was not significantly different. Propranolol pretreatment, a non-specific beta-adrenoceptor antagonist, blocked aconitine-induced arrhythmia in non-TG mice, but not in PAHX-AP1 TG mice. Our results indicate that, in the PAHX-AP1 TG heart, the modulation of voltage-gated potassium channel and ADRB1 expression seem to be important in the electrophysiological changes associated with altered ion channel functions, but ADRB1 is not involved in the greater susceptibility to aconitine-induced arrhythmia.

  18. THE USE OF OMEGA-3 FATTY ACIDS FOR THE TREATMENT OF PATIENTS WITH CARDIAC ARRHYTHMIAS

    Directory of Open Access Journals (Sweden)

    A. O. Malygin

    2015-09-01

    Full Text Available Antiarrhythmic effect of omega-3 polyunsaturated fatty acids (ω-3 PUFA, eicosapentaenoic and docosahexaenoic acids in patients with recurrent atrial fibrillation and ventricular arrhythmias had been proven. The positive effect of the ω-3 PUFA on the risk of sudden arrhythmic death and overall mortality in the patients after myocardial infarction and patients with chronic heart failure had been also proven.

  19. Brief Report: Emotion Regulation and Respiratory Sinus Arrhythmia in Autism Spectrum Disorder

    Science.gov (United States)

    Guy, Lisa; Souders, Margaret; Bradstreet, Lauren; DeLussey, Christine; Herrington, John D.

    2014-01-01

    Emotion regulation (ER) may be an important transdiagnostic factor for understanding mental and behavioral health given its association with several psychiatric disorders, including autism spectrum disorder (ASD). However, there is limited research on ER in ASD, particularly using biomarkers such as respiratory sinus arrhythmia (RSA). The aim of…

  20. Brief Report: Social Skills, Internalizing and Externalizing Symptoms, and Respiratory Sinus Arrhythmia in Autism

    Science.gov (United States)

    Neuhaus, Emily; Bernier, Raphael; Beauchaine, Theodore P.

    2014-01-01

    Theoretical and empirical models describe respiratory sinus arrhythmia (RSA) as a peripheral biomarker of emotion regulation and social competence. Recent findings also link RSA to individual differences in social functioning within autism spectrum disorder (ASD). However, associations between RSA and symptoms of internalizing/externalizing…

  1. Cost-effectiveness of genotyping in inherited arrhythmia syndromes: are we getting value for the money?

    NARCIS (Netherlands)

    A.A.M. Wilde; Y.M. Pinto

    2009-01-01

    Over the last decade, the identification of the diverse genetic basis of most important inherited arrhythmia syndromes has remarkably changed our attitude toward these life-threatening diseases. Just over 10 years ago, long-QT syndrome (LQTS) was considered one disease entity, Brugada -QT syndrome (

  2. Disordered myocardial Ca(2+) homeostasis results in substructural alterations that may promote occurrence of malignant arrhythmias.

    Science.gov (United States)

    Tribulova, N; Knezl, V; Szeiffova Bacova, B; Egan Benova, T; Viczenczova, C; Gonçalvesova, E; Slezak, J

    2016-09-19

    We aimed to determine the impact of Ca(2+)-related disorders induced in intact animal hearts on ultrastructure of the cardiomyocytes prior to occurrence of severe arrhythmias. Three types of acute experiments were performed that are known to be accompanied by disturbances in Ca(2+) handling. Langedorff-perfused rat or guinea pig hearts subjected to K(+)-deficient perfusion to induce ventricular fibrillation (VF), burst atrial pacing to induce atrial fibrillation (AF) and open chest pig heart exposed to intramyocardial noradrenaline infusion to induce ventricular tachycardia (VT). Tissue samples for electron microscopic examination were taken during basal condition, prior and during occurrence of malignant arrhythmias. Cardiomyocyte alterations preceding occurrence of arrhythmias consisted of non-uniform sarcomere shortening, disruption of myofilaments and injury of mitochondria that most likely reflected cytosolic Ca(2+) disturbances and Ca(2+) overload. These disorders were linked with non-uniform pattern of neighboring cardiomyocytes and dissociation of adhesive junctions suggesting defects in cardiac cell-to-cell coupling. Our findings identified heterogeneously distributed high [Ca(2+)](i)-induced subcellular injury of the cardiomyocytes and their junctions as a common feature prior occurrence of VT, VF or AF. In conclusion, there is a link between Ca(2+)-related disorders in contractility and coupling of the cardiomyocytes pointing out a novel paradigm implicated in development of severe arrhythmias. PMID:27643936

  3. An extended family suddenly confronted with a life-threatening hereditary arrhythmia

    NARCIS (Netherlands)

    Hendriks, K.S.W.H.; Van Langen, I.M.; Van Tintelen, J.P.; Grosfeld, F.J.M.; Wilde, A.A.M.; Ten Kroode, H.F.J.

    2005-01-01

    Objective. This exploratory study serves to illustrate the psychological impact on an extended family in the process of genetic counselling and testing for a potentially life-threatening arrhythmia, the long-QT syndrome (LQTS). Method. All members of the third generation and their partners (n=11) we

  4. Which is the appropriate arrhythmia burden to offer RF ablation for RVOT tachycardias?

    Directory of Open Access Journals (Sweden)

    Andreas Rillig; Tina Lin; Feifan Ouyang; Karl-Heinz Kuck; Roland Richard Tilz

    2014-12-01

    Full Text Available Premature ventricular complexes (PVCs and ventricular tachycardia (VT in patients with structurally normal hearts originate from the right ventricular outflow tract (RVOT in the majority of cases. In the last few decades catheter ablation of these arrhythmias has been proven to be effective. RVOT VT/PVCs may cause disabling symptoms or arrhythmia induced cardiomyopathy. However, the PVC burden at which catheter ablation should be recommended is still controversial. What adds to the controversy is why some patients with only a low number of PVCs can be highly symptomatic and may even develop arrhythmia induced cardiomyopathy, whilst others may have a higher PVC/VT burden and remain asymptomatic and do not develop cardiomyopathy for a long period of time. Therefore, although catheter ablation of RVOT PVCs has high success and low complication rates, the time point of when ablation should be recommended is currently still under debate. This review discusses the treatment strategies and prognosis for RVOT tachycardias and focuses on the question of which arrhythmia burden is appropriate to offer RF ablation.

  5. [Correlation between QT interval, ventricular arrhythmias and left ventricular function in chronic alcoholics].

    Science.gov (United States)

    Pomini, G; Gribaldo, R; Bellavere, F; Lupia, M; Sale, F; Rugna, A; Costa, L; Molfese, G

    1986-04-01

    Prolonged QT interval and arrhythmias have been reported to occur in chronic alcoholics. To investigate the role of chronic alcohol consumption in the onset of arrhythmias and the development of the preclinical left ventricular dysfunction, in a group of 12 asymptomatic chronic alcoholics with no clinical evidence of heart disease, with histologically proven hepatic damage, after a week of abstinence from alcohol, the following investigations were performed: measurements of the corrected QT interval (QTc), 24-hours Holter monitoring, systolic time intervals, M-mode echocardiograms. The results were compared to those of 10 normal subjects. Our data suggested no difference in QTc interval between chronic alcoholics and normal persons. The distribution of arrhythmias was not statistically different in the two groups, particularly frequent and complicated arrhythmias occurred in only one subject in each group. Preejection period corrected for heart rate (PEPI) was significantly longer in alcoholics (132 +/- 16 vs 119 +/- 11, p less than 0.05). All echocardiographic parameters examined were not significantly different in the two groups. On the basis of our results, our impression is that the arrhythmogenic role of alcohol, not under acute ingestion, is relatively unimportant and further studies are needed to become a definitive conclusion about subclinical alcoholic cardiomyopathy. PMID:3743931

  6. Arrhythmia detection after atrial fibrillation ablation: value of incremental monitoring time

    NARCIS (Netherlands)

    Mulder, A.A.W.; Wijffels, M.C.; Wever, E.F.; Kelder, J.C.; Boersma, L.V.

    2012-01-01

    BACKGROUND: After pulmonary vein isolation (PVI), patients need to be followed to analyze the effect of the treatment. We evaluated the influence of the duration of Holter monitoring on the detection of arrhythmia recurrences after a single PVI at 12 months. METHODS: Consecutive patients with paroxy

  7. Use of Whole Exome Sequencing for the Identification of Ito-Based Arrhythmia Mechanism and Therapy

    Science.gov (United States)

    Sturm, Amy C; Kline, Crystal F; Glynn, Patric; Johnson, Benjamin L; Curran, Jerry; Kilic, Ahmet; Higgins, Robert S D; Binkley, Philip F; Janssen, Paul M L; Weiss, Raul; Raman, Subha V; Fowler, Steven J; Priori, Silvia G; Hund, Thomas J; Carnes, Cynthia A; Mohler, Peter J

    2015-01-01

    Background Identified genetic variants are insufficient to explain all cases of inherited arrhythmia. We tested whether the integration of whole exome sequencing with well-established clinical, translational, and basic science platforms could provide rapid and novel insight into human arrhythmia pathophysiology and disease treatment. Methods and Results We report a proband with recurrent ventricular fibrillation, resistant to standard therapeutic interventions. Using whole-exome sequencing, we identified a variant in a previously unidentified exon of the dipeptidyl aminopeptidase-like protein-6 (DPP6) gene. This variant is the first identified coding mutation in DPP6 and augments cardiac repolarizing current (Ito) causing pathological changes in Ito and action potential morphology. We designed a therapeutic regimen incorporating dalfampridine to target Ito. Dalfampridine, approved for multiple sclerosis, normalized the ECG and reduced arrhythmia burden in the proband by >90-fold. This was combined with cilostazol to accelerate the heart rate to minimize the reverse-rate dependence of augmented Ito. Conclusions We describe a novel arrhythmia mechanism and therapeutic approach to ameliorate the disease. Specifically, we identify the first coding variant of DPP6 in human ventricular fibrillation. These findings illustrate the power of genetic approaches for the elucidation and treatment of disease when carefully integrated with clinical and basic/translational research teams. PMID:26015324

  8. Dietary n-3 fatty acids promote arrhythmias during acute regional myocardial ischemia in isolated pig hearts

    NARCIS (Netherlands)

    Coronel, R.; Wilms-Schopman, F.J.G.; Ruijter, den H.M.; Belterman, C.N.; Schumacher, C.A.; Opthof, T.; Hovernier, R.; Lemmens, A.G.; Terpstra, A.H.M.; Katan, M.B.; Zock, P.L.

    2007-01-01

    Objective Dietary supplementation with fish oil-derived n-3 fatty acids reduces mortality in patients with myocardial infarction, but may have adverse effects in angina patients. The underlying electrophysiologic mechanisms are poorly understood. We studied the arrhythmias and the electrophysiologic

  9. Fever-Induced Life-Threatening Arrhythmias in Children Harboring an SCN5A Mutation

    NARCIS (Netherlands)

    P. Chockalingam; L.A. Rammeloo; P.G. Postema; J. Hruda; S.A.B. Clur; N.A. Blom; A.A. Wilde

    2011-01-01

    Cardiac channelopathies caused by SCN5A mutation are well tolerated by most patients. However, the dramatic presentation of a previously healthy 4-month-old girl with life-threatening arrhythmias and the subsequent findings in the child and her family provide evidence that loss-of-function sodium ch

  10. Electrical alternans during rest and exercise as predictors of vulnerability to ventricular arrhythmias

    Science.gov (United States)

    Estes, N. A. 3rd; Michaud, G.; Zipes, D. P.; El-Sherif, N.; Venditti, F. J.; Rosenbaum, D. S.; Albrecht, P.; Wang, P. J.; Cohen, R. J.

    1997-01-01

    This investigation was performed to evaluate the feasibility of detecting repolarization alternans with the heart rate elevated with a bicycle exercise protocol. Sensitive spectral signal-processing techniques are able to detect beat-to-beat alternation of the amplitude of the T wave, which is not visible on standard electrocardiogram. Previous animal and human investigations using atrial or ventricular pacing have demonstrated that T-wave alternans is a marker of vulnerability to ventricular arrhythmias. Using a spectral analysis technique incorporating noise reduction signal-processing software, we evaluated electrical alternans at rest and with the heart rate elevated during a bicycle exercise protocol. In this study we defined optimal criteria for electrical alternans to separate patients from those without inducible arrhythmias. Alternans and signal-averaged electrocardiographic results were compared with the results of vulnerability to ventricular arrhythmias as defined by induction of sustained ventricular tachycardia or fibrillation at electrophysiologic evaluation. In 27 patients alternans recorded at rest and with exercise had a sensitivity of 89%, specificity of 75%, and overall clinical accuracy of 80% (p bicycle exercise protocol. Alternans measured using this technique is an accurate predictor of arrhythmia inducibility.

  11. The influence of motor activity on the development of cardiac arrhythmias during experimental emotional stress

    Science.gov (United States)

    Ulyaninskiy, L. S.; Urmancheyeva, T. G.; Stepanyan, Y. P.; Fufacheva, A. A.; Gritsak, A. V.; Kuznetsova, B. A.; Kvitka, A. A.

    1982-01-01

    Experimental emotional stress which can produce various disorders of cardiac rhythm: sinus tachycardia, atrial fibrillation, ventricular, extrasystoles and paroxysmal ventricular tachysystoles was studied. In these conditions the adrenalin content in the blood and myocardium is increased 3 to 4 times. It is found that moderate motor activity leads to a relative decrease of adrenalin in the myocardium and arrest of cardiac arrhythmias.

  12. Reducing false arrhythmia alarms in the ICU using multimodal signals and robust QRS detection.

    Science.gov (United States)

    Sadr, Nadi; Huvanandana, Jacqueline; Nguyen, Doan Trang; Kalra, Chandan; McEwan, Alistair; de Chazal, Philip

    2016-08-01

    This study developed algorithms to decrease the arrhythmia false alarms in the ICU by processing multimodal signals of photoplethysmography (PPG), arterial blood pressure (ABP), and two ECG signals. The goal was to detect the five critical arrhythmias comprising asystole (ASY), extreme bradycardia (EBR), extreme tachycardia (ETC), ventricular tachycardia (VTA), and ventricular flutter or fibrillation (VFB). The different characteristics of the arrhythmias suggested the application of individual signal processing for each alarm and the combination of the algorithms to enhance false alarm detection. Thus, different features and signal processing techniques were used for each arrhythmia type. The ECG signals were first processed to reduce the signal interference. Then, a Hilbert-transform based QRS detector algorithm was utilized to identify the QRS complexes, which were then processed to determine the instantaneous heart rate. The pulsatile signals (PPG and ABP) were processed to discover the pulse onset of beats which were then employed to measure the heart rate. The signal quality index (SQI) of the signals was implemented to verify the integrity of the heart rate information. The overall score obtained by our algorithms in the 2015 Computing in Cardiology Challenge was a score of 74.03% for retrospective and 69.92% for real-time analysis. PMID:27455121

  13. Non-sedating antihistamine drugs and cardiac arrhythmias : biased risk estimates from spontaneous reporting systems?

    NARCIS (Netherlands)

    De Bruin, M L; van Puijenbroek, E P; Egberts, A C G; Hoes, A W; Leufkens, H G M

    2002-01-01

    AIMS: This study used spontaneous reports of adverse events to estimate the risk for developing cardiac arrhythmias due to the systemic use of non-sedating antihistamine drugs and compared the risk estimate before and after the regulatory action to recall the over-the-counter status of some of these

  14. Elevated Platelet Activating Factor Level in Ischemia-Related Arrhythmia and Its Electrophysiological Effect on Myocardium

    Institute of Scientific and Technical Information of China (English)

    TAO Yong Kang; ZHAO Shui Ping; YU Pu Lin; SHI Jing; GU Cheng Dong; SUN Hong Tao; ZHANG Guo Qiang

    2013-01-01

    Objective The mechanism through which platelet activating factor (PAF) induces cardiac electrical activity and arrhythmia is not well understood and previous studies have suggested a potential involvement of ion channels in its action. The present study was aimed to clarify the role of PAF in fatal arrhythmias following acute myocardia infarction (AMI) and the underlying mechanism. Methods (1) Blood PAF levels were measured among 72 AMI patients at the time of diagnosis with AMI and 48 h later, and their electrocardiogram (ECG) was recorded continuously. (2) Ischemia simulation and surface electrocardiogram were conducted in 20 pigs and their PAF levels were measured. (3) PAF perfusion and standard microelectrode recording were performed on guinea pig papillary muscles. Results In both humans and pigs, elevated PAF levels were detected in AMI and simulated ischemia, respectively, and even higher PAF levels were found when fatal arrhythmias occurred. In guinea pig myocardium, PAF induced a shortening of action potential duration at 90% level of repolarization (APD90)under non-ischemic conditions and a more pronounced shortening under early simulated ischemic conditions. Conclusion AMI and ischemia are associated with increased PAF levels in humans and pigs, which are further raised when fatal arrhythmia follows. The effects of PAF on the myocardium may be mediated by multiple ion channels.

  15. Effects of ischemic preconditioning on ischemia/reperfusion-induced arrhythmias by upregulatation of connexin 43 expression

    Directory of Open Access Journals (Sweden)

    Chen Zhenguang

    2011-06-01

    Full Text Available Abstract Background The susceptibility of hypertrophied myocardium to ischemia-reperfusion injury is associated with increased risk of postoperative arrhythmias. We investigate the effects of ischemic preconditioning (IP on post-ischemic reperfusion arrhythmias in hypertrophic rabbit hearts. Methods Thirty-three rabbit models of myocardial hypertrophy were randomly divided into three groups of 11 each: non-ischemia-reperfusion group (group A, ischemia-reperfusion group (group B, and ischemic preconditioning group (group C. Another ten healthy rabbits with normal myocardium served as the healthy control group. Rabbit models of myocardial hypertrophy were induced by abdominal aortic banding. Surface electrocardiogram (ECG was recorded and Curtis-Ravingerova score was used for arrhythmia quantification. Connexin 43 (Cx43 expression was assessed by immunohistochemistry. Results Ratios of heart weight to body weight and left ventricular weight to body weight increase significantly in the three groups compared with the healthy control group (p Conclusions The incidence of ischemia/reperfusion-induced arrhythmias in hypertrophic rabbit hearts decreases after IP, which plays an important protecting role on the electrophysiology of hypertrophied myocardium by up-regulating the expression of Cx43.

  16. Non-sedating antihistamine drugs and cardiac arrhythmias -- biased risk estimates from spontaneous reporting systems?

    DEFF Research Database (Denmark)

    De Bruin, M L; van Puijenbroek, E P; Egberts, A C G;

    2002-01-01

    AIMS: This study used spontaneous reports of adverse events to estimate the risk for developing cardiac arrhythmias due to the systemic use of non-sedating antihistamine drugs and compared the risk estimate before and after the regulatory action to recall the over-the-counter status of some of th....... Our findings, however, strongly suggest that the increased risk identified can at least partly be explained by reporting bias as a result of publications about and mass media attention for antihistamine induced arrhythmias.......AIMS: This study used spontaneous reports of adverse events to estimate the risk for developing cardiac arrhythmias due to the systemic use of non-sedating antihistamine drugs and compared the risk estimate before and after the regulatory action to recall the over-the-counter status of some...... was not significantly higher than 1 (OR 1.37 [95% CI: 0.85, 2.23]), whereas the risk estimate calculated after the governmental decision did significantly differ from 1 (OR 4.19 [95% CI: 2.49, 7.05]). CONCLUSIONS: Our data suggest that non-sedating antihistamines might have an increased risk for inducing arrhythmias...

  17. ECG-Edit function in multidetector-row computed tomography coronary arteriography for patients with arrhythmias

    International Nuclear Information System (INIS)

    Electrocardiogram (ECG)-gating is necessary for cardiac computed tomography, but is not suitable for arrhythmias, so the aim of this study was to evaluate the usefulness of the ECG-edit function for this purpose. Of 1,221 patients undergoing 64-row multidetector-row computed tomography coronary angiography (coronary MDCT), 123 patients (28 atrial fibrillation (Af), 39 premature atrial contractions (PAC), 42 premature ventricular contractions (PVC), 3 PAC+PVC, 10 sinus arrhythmias (SA), and a second-degree atrioventricular block (2deg AVB)) had arrhythmias necessitating the ECG-edit function. Short R-R interval was deleted and mid-diastolic phases were selected from the long R-R intervals using the ''R+absolute time'' method. In the present study, the reconstructed images were evaluated using a triple-grade scale A-C, representing excellent, acceptable, and unacceptable image quality. Image quality, categorized as A, B and C, respectively, was 50%, 36% and 14% for the 28 patients with Af; 56%, 36% and 8% for the 39 PAC patients, and 65%, 33% and 2% in the 42 PVC patients. None of the scans of the PAC+PVC, SA, and 2deg AVB patients was ranked as C. The ECG-edit function is useful for reconstructing coronary MDCT images in many arrhythmias, and provides clinically acceptable images in most cases. (author)

  18. Arrhythmias induced cardiomyopathies: the riddle of the chicken or the egg still unresolved?

    International Nuclear Information System (INIS)

    The hypothesis testing of inappropriate fast, irregular, or asynchronous myocardial contraction provoking cardiomyopathy has been the primary focus of numerous research efforts, especially during the last few decades. Rapid ventricular rates resulting from supraventricular arrhythmias and atrial fibrillation (AF), irregularity of heart rhythm basic element of AF and asynchrony, as a consequence of right ventricular pacing, bundle branch block, or frequent premature ventricular complexes, have been established as primary causes of arrhythmia-induced cardiomyopathy. The main pathophysiological pathways involved have been clarified, including neurohumoral activation, energy stores depletion, and abnormalities in stress and strain. Unfortunately, from a clinical point of view, patients usually seek medical advice only when symptoms develop, while the causative arrhythmia may be present for months or years, resulting in myocardial remodelling, diastolic, and systolic dysfunction. In some cases, making a definite diagnosis may become a strenuous exercise for the treating physician, as the arrhythmia may not be present and, additionally, therapy must be applied for the diagnosis to be confirmed retrospectively. The diagnostic process is also hardened due to the fact that strict diagnosing criteria are still a matter of discrepancy

  19. Incidence of cardiac arrhythmias in asymptomatic hereditary hemochromatosis subjects with C282Y homozygosity.

    Science.gov (United States)

    Shizukuda, Yukitaka; Tripodi, Dorothy J; Zalos, Gloria; Bolan, Charles D; Yau, Yu-Ying; Leitman, Susan F; Waclawiw, Myron A; Rosing, Douglas R

    2012-03-15

    It is not well known whether systemic iron overload per se in hereditary hemochromatosis (HH) is associated with cardiac arrhythmias before other signs and symptoms of cardiovascular disease occur. In the present study, we examined the incidence of cardiac arrhythmia in cardiac asymptomatic subjects with HH (New York Heart Association functional class I) and compared it to that in age- and gender-matched normal volunteers. The 42 subjects with HH and the 19 normal control subjects were recruited through the National Heart, Lung, and Blood Institute-sponsored "Heart Study of Hemochromatosis." They completed 48-hour Holter electrocardiography ambulatory monitoring at the baseline evaluation. The subjects with HH were classified as newly diagnosed (group A) and chronically treated (group B) subjects. All subjects with HH had C282Y homozygosity, and the normal volunteers lacked any HFE gene mutations known to cause HH. Although statistically insignificant, the incidence of ventricular and supraventricular ectopy tended to be greater in the combined HH groups than in the controls. Supraventricular ectopy was more frequently noted in group B compared to in the controls (ectopy rate per hour 11.1 ± 29.9 vs 1.5 ± 3.5, p examples of heart block, other than first-degree atrioventricular node block, were seen in any of the subjects. The incidence of cardiac arrhythmias was not significantly reduced after 6 months of intensive iron removal therapy in the group A subjects. No life-threatening arrhythmias were observed in our subjects with HH. In conclusion, our data suggest that the incidence of cardiac arrhythmias is, at most, marginally increased in asymptomatic subjects with HH. A larger clinical study is warranted to further clarify our observation. PMID:22196777

  20. Medical Decision Support System for Diagnosis of Heart Arrhythmia using DWT and Random Forests Classifier.

    Science.gov (United States)

    Alickovic, Emina; Subasi, Abdulhamit

    2016-04-01

    In this study, Random Forests (RF) classifier is proposed for ECG heartbeat signal classification in diagnosis of heart arrhythmia. Discrete wavelet transform (DWT) is used to decompose ECG signals into different successive frequency bands. A set of different statistical features were extracted from the obtained frequency bands to denote the distribution of wavelet coefficients. This study shows that RF classifier achieves superior performances compared to other decision tree methods using 10-fold cross-validation for the ECG datasets and the obtained results suggest that further significant improvements in terms of classification accuracy can be accomplished by the proposed classification system. Accurate ECG signal classification is the major requirement for detection of all arrhythmia types. Performances of the proposed system have been evaluated on two different databases, namely MIT-BIH database and St. -Petersburg Institute of Cardiological Technics 12-lead Arrhythmia Database. For MIT-BIH database, RF classifier yielded an overall accuracy 99.33 % against 98.44 and 98.67 % for the C4.5 and CART classifiers, respectively. For St. -Petersburg Institute of Cardiological Technics 12-lead Arrhythmia Database, RF classifier yielded an overall accuracy 99.95 % against 99.80 % for both C4.5 and CART classifiers, respectively. The combined model with multiscale principal component analysis (MSPCA) de-noising, discrete wavelet transform (DWT) and RF classifier also achieves better performance with the area under the receiver operating characteristic (ROC) curve (AUC) and F-measure equal to 0.999 and 0.993 for MIT-BIH database and 1 and 0.999 for and St. -Petersburg Institute of Cardiological Technics 12-lead Arrhythmia Database, respectively. Obtained results demonstrate that the proposed system has capacity for reliable classification of ECG signals, and to assist the clinicians for making an accurate diagnosis of cardiovascular disorders (CVDs). PMID:26922592

  1. Ellagic acid improved arrhythmias induced by CaCL2 in the rat stress model

    Directory of Open Access Journals (Sweden)

    Mahin Dianat

    2015-02-01

    Full Text Available Objective: In ventricular arrhythmias, due to their free radical scavenging action, antioxidant agents are usually used in the treatment of cardiovascular disease. Since stress is considered as risk factor for increased mortality by causing malignant arrhythmias, the study was designed to evaluate the cardioprotective effects of ellagic acid (EA on CaCl2-induced arrhythmias in rat stress model. Materials and Methods: Male Sprague-Dawley rats (200-250 g were divided into four groups: Group I: Control rats (2 ml of saline by gavage, Group II: Rats treated with EA (15 mg/kg, gavage, Group III: stress group, Group IV: received EA plus stress. Stress was applied in a restrainer box (6 hour/day, 21 days. After induction of anesthesia, lead II electrocardiogram was recorded for calculating heart rate and QRS complex. The arrhythmia was produced by injection of CaCl2 solution (140 mg/kg, iv and incidences of Ventricular fibrillation, Ventricular premature beats and Ventricular tachycardia were recorded. Results were analyzed by using one-way ANOVA and Fisher`s exact test. pResults: The results showed a positive inotropic effect and negative chronotropic effect for the EA group in comparison with the control group. Incidence rates (% of premature beats, ventricular fibrillation and ventricular tachycardia in stress group and all the arrhythmia parameters decreased in groups which received EA. Conclusions:  By decreasing the incidence rates of premature beats, fibrillation and ventricular tachycardia in groups which received EA, ellagic acid probably acted as an anti-arrhythmic agent which showed to have aprotective functionin heart.

  2. Cardioprotective activity of alcoholic extract of Tinospora cordifolia (Willd.) Miers in calcium chloride-induced cardiac arrhythmia in rats

    OpenAIRE

    Sharma, Ashish Kumar; Kishore, Kunal; Sharma, Divya; B P Srinivasan; Agarwal, Shyam Sunder; Sharma, Ashok; Singh, Santosh Kumar; Gaur, Samir; Jatav, Vijay Singh

    2011-01-01

    The present study investigated the antiarrhythmic activity of alcoholic extract of Tinospora cordifolia (T. cordifolia) in CaCl2 induced arrhythmia. CaCl2 (25 mg/kg) was administered by intravenous infusion (iv) to produce arrhythmia in rats. The animals were then treated with T. cordifolia extract (150, 250, and 450 mg/kg) and verapamil (5 mg/kg,iv). Lead II electrocardiogram was monitored. Plasma calcium, sodium and potassium levels were measured. In CaCl2 induced arrhythmia, heart rate was...

  3. Detection of Acute Atrial-Ventricular Arrhythmias Based on ECG Delineator: Evaluation on MIT/BIH Standard Databases

    Directory of Open Access Journals (Sweden)

    Katayoun Shojaian‎

    2008-03-01

    Full Text Available In this paper we use an efficient arrhythmia algorithm based on wavelet transform. In first step, QRS complexes are detected. Then each QRS is delineated by detecting and identifying the peaks of the individual waves, complex onset and end. Then the determination of P and T wave peaks, onset and ends are performed. Finally the Ventricular flutter, ventricular tachycardia, supra ventricular tachycardia, ventricular fibrillation, atrial fibrillation and atrial flutter that are kinds of acute ventricular-atrial arrhythmias are detected. In the proposed algorithm, we used a second order spline as mother wavelet and improved the previous algorithms proposed by other investigators. We evaluated the algorithm on some manually annotated single ECG signals selected from MIT-BIH arrhythmia databases. This algorithm may achieve the mean detection accuracy of about 80% in these arrhythmias.

  4. Relationship of cardiac arrhythmias to myocar- dial remodeling and expression of adhesion molecules in patients with mitral valve prolapse

    Directory of Open Access Journals (Sweden)

    A.V. Yagoda

    Conclusion. Myocardial remodeling and dysregulation of cell adhesion proteins are recorded in young patients with MVP and arrhythmias. Relaionship of severity of arrhythmic syndrome to myocardial remodeling and VCAM-1 level was revealed.

  5. Intra-beat Scaling Properties of Cardiac Arrhythmias and Sudden Cardiac Death

    Science.gov (United States)

    Rodríguez, Eduardo; Lerma, Claudia; Echeverría, Juan C.; Alvarez-Ramirez, Jose

    2008-02-01

    We applied detrended fluctuation analysis (DFA) to characterize the intra-beat scaling dynamics of electrocardiographic (ECG) recordings from the PhysioNet Sudden Cardiac Death Holter Database. The main finding of this contribution is that, in such recordings involving different types of arrhythmias; the ECG waveform, besides showing a less-random intra-beat dynamics, becomes more regular during bigeminy, ventricular tachycardia (VT) or even atrial fibrillation (AFIB) and ventricular fibrillation (VF) despite the appearance of erratic traces. Thus, notwithstanding that these cardiac rhythm abnormalities are generally considered as irregular and some of them generated by random impulses or wavefronts, the intra-beat scaling properties suggest that regularity dominates the underlying mechanisms of arrhythmias. Among other explanations, this may result from shorted or restricted -less complex- pathways of conduction of the electrical activity within the ventricles.

  6. Atrial Arrhythmias in Obstructive Sleep Apnea: Underlying Mechanisms and Implications in the Clinical Setting

    Directory of Open Access Journals (Sweden)

    David Filgueiras-Rama

    2013-01-01

    Full Text Available Obstructive sleep apnea (OSA is a common disorder characterized by repetitive interruption of ventilation during sleep caused by recurrent upper airway collapse, which leads to intermittent hypoxia. The disorder is commonly undiagnosed despite its relationship with substantial cardiovascular morbidity and mortality. Moreover, the effects of the disorder appear to be particularly dangerous in young subjects. In the last decade, substantial clinical evidence has identified OSA as independent risk factor for both bradyarrhythmias and tachyarrhythmias. To date the mechanisms leading to such arrhythmias have not been completely understood. However, recent data from animal models and new molecular analyses have increased our knowledge of the field, which might lead to future improvement in current therapeutic strategies mainly based on continuous positive airway pressure. This paper aims at providing readers a brief and specific revision of current knowledge about the mechanisms underlying atrial arrhythmias in OSA and their clinical and therapeutic implications.

  7. [Identification of paroxysmal, transient arrhythmias: Intermittent registration more efficient than the 24-hour Holter monitoring].

    Science.gov (United States)

    Hendrikx, Tijn; Rosenqvist, Mårten; Sandström, Herbert; Persson, Mats; Hörnsten, Rolf

    2015-01-06

    Many patients suffer from palpitations or dizziness/presyncope. These patients are often referred for Holter ECG (24 hour), although the sensitivity for detecting arrhythmias is low. A new method, short intermittent regular and symptomatic ECG registrations at home, might be a convenient and more sensitive alternative also suitable for primary health care. In this case report we present a patient who had contacted health care several times during a seven year period for paroxysmal palpitations. Routine examination with 24 hour Holter ECG and event recorder did not result in a diagnosis. Using intermittent handheld ECG registration at home, a paroxysmal supraventricular arrhythmia was diagnosed. Further investigation revealed that the patient had a concealed Wolff-Parkinson-White (WPW) syndrome.

  8. Electrocardiographic Presentation, Cardiac Arrhythmias, and Their Management in β-Thalassemia Major Patients.

    Science.gov (United States)

    Russo, Vincenzo; Rago, Anna; Papa, Andrea Antonio; Nigro, Gerardo

    2016-07-01

    Beta-thalassemia major (β-TM) is a genetic hemoglobin disorder characterized by an absent synthesis of globin chains that are essential for hemoglobin formation, causing chronic hemolytic anemia. Clinical management of thalassemia major consists in regular long-life red blood cell transfusions and iron chelation therapy to remove iron introduced in excess with transfusions. Iron deposition in combination with inflammatory and immunogenic factors is involved in the pathophysiology of cardiac dysfunction in these patients. Heart failure and arrhythmias, caused by myocardial siderosis, are the most important life-limiting complications of iron overload in beta-thalassemia patients. Cardiac complications are responsible for 71% of global death in the beta-thalassemia major patients. The aim of this review was to describe the most frequent electrocardiographic abnormalities and arrhythmias observed in β-TM patients, analyzing their prognostic impact and current treatment strategies. PMID:27324981

  9. [Identification of paroxysmal, transient arrhythmias: Intermittent registration more efficient than the 24-hour Holter monitoring].

    Science.gov (United States)

    Hendrikx, Tijn; Rosenqvist, Mårten; Sandström, Herbert; Persson, Mats; Hörnsten, Rolf

    2015-01-01

    Many patients suffer from palpitations or dizziness/presyncope. These patients are often referred for Holter ECG (24 hour), although the sensitivity for detecting arrhythmias is low. A new method, short intermittent regular and symptomatic ECG registrations at home, might be a convenient and more sensitive alternative also suitable for primary health care. In this case report we present a patient who had contacted health care several times during a seven year period for paroxysmal palpitations. Routine examination with 24 hour Holter ECG and event recorder did not result in a diagnosis. Using intermittent handheld ECG registration at home, a paroxysmal supraventricular arrhythmia was diagnosed. Further investigation revealed that the patient had a concealed Wolff-Parkinson-White (WPW) syndrome. PMID:25584602

  10. Recommendations of the Brazilian Society of Cardiac Arrhythmias for Holter Monitoring Services

    OpenAIRE

    Lorga Filho, Adalberto; Cintra, Fatima Dumas; Lorga, Adalberto; Grupi, Cesar José; Pinho, Claudio; Moreira, Dalmo Antonio Ribeiro; Dario C. Sobral Filho; de Brito, Fabio Sandoli; Kruse, José Claudio Lupi; Neto, José Sobral

    2013-01-01

    Background There are innumerous indicators to assure the quality of a service. However, medical competence and the proper performance of a procedure determine its final quality. The Brazilian Society of Cardiac Arrhythmias recommends minimum parameters necessary to guarantee the excellence of ambulatory electrocardiographic monitoring services. Objective To recommend minimum medical competences and the information required to issue a Holter monitoring report. Methods This study was grounded i...

  11. Robust algorithm for arrhythmia classification in ECG using extreme learning machine

    Directory of Open Access Journals (Sweden)

    Shin Kwangsoo

    2009-10-01

    Full Text Available Abstract Background Recently, extensive studies have been carried out on arrhythmia classification algorithms using artificial intelligence pattern recognition methods such as neural network. To improve practicality, many studies have focused on learning speed and the accuracy of neural networks. However, algorithms based on neural networks still have some problems concerning practical application, such as slow learning speeds and unstable performance caused by local minima. Methods In this paper we propose a novel arrhythmia classification algorithm which has a fast learning speed and high accuracy, and uses Morphology Filtering, Principal Component Analysis and Extreme Learning Machine (ELM. The proposed algorithm can classify six beat types: normal beat, left bundle branch block, right bundle branch block, premature ventricular contraction, atrial premature beat, and paced beat. Results The experimental results of the entire MIT-BIH arrhythmia database demonstrate that the performances of the proposed algorithm are 98.00% in terms of average sensitivity, 97.95% in terms of average specificity, and 98.72% in terms of average accuracy. These accuracy levels are higher than or comparable with those of existing methods. We make a comparative study of algorithm using an ELM, back propagation neural network (BPNN, radial basis function network (RBFN, or support vector machine (SVM. Concerning the aspect of learning time, the proposed algorithm using ELM is about 290, 70, and 3 times faster than an algorithm using a BPNN, RBFN, and SVM, respectively. Conclusion The proposed algorithm shows effective accuracy performance with a short learning time. In addition we ascertained the robustness of the proposed algorithm by evaluating the entire MIT-BIH arrhythmia database.

  12. Experience of treatment of heart rhabdomyomas in combination with various arrhythmias and conduction disorders

    OpenAIRE

    Bockeria L. A.; Bockeria O. L.; Rubtsov P.P.; Akhobekov A.A.; Alekhina M. A.

    2014-01-01

    Оbjective. Presentation the experience of diagnosis and treatment of heart rhabdomyomas in combination withvarious arrhythmias and conduction disorders.Material and methods. In archival material found 9 records of pediatric patients treated in A.N. BakoulevCenter for Cardiovascular Surgery from June 2004 to September 2013 with cardiac rhabdomyomas. The ageofpatients ranged from 19 days to 17 years. Along with the general clinical studies patients perfomed electro-cardiography (ECG), Holter EC...

  13. Convulsive Syncope Induced by Ventricular Arrhythmia Masquerading as Epileptic Seizures: Case Report and Literature Review

    OpenAIRE

    Sabu, John; Regeti, Kalyani; Mallappallil, Mary; Kassotis, John; Islam, Hamidul; Zafar, Shoaib; Khan, Rafay; Ibrahim, Hiyam; Kanta, Romana; Sen, Shuvendu; Yousif, Abdalla; Nai, Qiang

    2016-01-01

    It is important but difficult to distinguish convulsive syncope from epileptic seizure in many patients. We report a case of a man who presented to emergency department after several witnessed seizure-like episodes. He had a previous medical history of systolic heart failure and automated implantable converter defibrillator (AICD) in situ. The differential diagnoses raised were epileptic seizures and convulsive syncope secondary to cardiac arrhythmia. Subsequent AICD interrogation revealed ve...

  14. Does respiratory sinus arrhythmia serve a buffering role for diastolic pressure fluctuations?

    OpenAIRE

    Tan, Can Ozan; Taylor, J. Andrew

    2010-01-01

    Though many consider the magnitude of respiratory sinus arrhythmia as an index of cardiac vagal control, its physiological origins remain unclear. One influential model postulates that the systolic pressure rise within a given beat stimulates the baroreflex arc to adjust the following heart period such that diastolic pressure is “stabilized” and hence displays lesser fluctuation. Accordingly, the magnitude of diastolic pressure fluctuations with respiration should change reciprocally after au...

  15. Bile Acid-Induced Arrhythmia Is Mediated by Muscarinic M2 Receptors in Neonatal Rat Cardiomyocytes

    OpenAIRE

    Sheikh Abdul Kadir, Siti H; Michele Miragoli; Shadi Abu-Hayyeh; Moshkov, Alexey V.; Qilian Xie; Verena Keitel; Viacheslav O. Nikolaev; Catherine Williamson; Julia Gorelik

    2010-01-01

    BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP) is a common disease affecting up to 5% of pregnancies and which can cause fetal arrhythmia and sudden intrauterine death. We previously demonstrated that bile acid taurocholate (TC), which is raised in the bloodstream of ICP, can acutely alter the rate and rhythm of contraction and induce abnormal calcium destabilization in cultured neonatal rat cardiomyocytes (NRCM). Apart from their hepatic functions bile acids are ubiquitous signallin...

  16. Observational cohort study of ventricular arrhythmia in adults with Marfan syndrome caused by FBN1 mutations.

    Directory of Open Access Journals (Sweden)

    Ali Aydin

    Full Text Available BACKGROUND: Marfan syndrome is associated with ventricular arrhythmia but risk factors including FBN1 mutation characteristics require elucidation. METHODS AND RESULTS: We performed an observational cohort study of 80 consecutive adults (30 men, 50 women aged 42±15 years with Marfan syndrome caused by FBN1 mutations. We assessed ventricular arrhythmia on baseline ambulatory electrocardiography as >10 premature ventricular complexes per hour (>10 PVC/h, as ventricular couplets (Couplet, or as non-sustained ventricular tachycardia (nsVT, and during 31±18 months of follow-up as ventricular tachycardia (VT events (VTE such as sudden cardiac death (SCD, and sustained ventricular tachycardia (sVT. We identified >10 PVC/h in 28 (35%, Couplet/nsVT in 32 (40%, and VTE in 6 patients (8%, including 3 with SCD (4%. PVC>10/h, Couplet/nsVT, and VTE exhibited increased N-terminal pro-brain natriuretic peptide serum levels(P10/h and Couplet/nsVT also related to increased indexed end-systolic LV diameters (P = .024 and P = .020, to moderate mitral valve regurgitation (P = .018 and P = .003, and to prolonged QTc intervals (P = .001 and P = .006, respectively. Moreover, VTE related to mutations in exons 24-32 (P = .021. Kaplan-Meier analysis corroborated an association of VTE with increased NT-proBNP (P<.001 and with mutations in exons 24-32 (P<.001. CONCLUSIONS: Marfan syndrome with causative FBN1 mutations is associated with an increased risk for arrhythmia, and affected persons may require life-long monitoring. Ventricular arrhythmia on electrocardiography, signs of myocardial dysfunction and mutations in exons 24-32 may be risk factors of VTE.

  17. Cardiac Arrhythmia: In vivo screening in the zebrafish to overcome complexity in drug discovery

    Science.gov (United States)

    MacRae, Calum A.

    2010-01-01

    Importance of the field Cardiac arrhythmias remain a major challenge for modern drug discovery. Clinical events are paroxysmal, often rare and may be asymptomatic until a highly morbid complication. Target selection is often based on limited information and though highly specific agents are identified in screening, the final efficacy is often compromised by unanticipated systemic responses, a narrow therapeutic index and substantial toxicities. Areas covered in this review Our understanding of complexity of arrhythmogenesis has grown dramatically over the last two decades, and the range of potential disease mechanisms now includes pathways previously thought only tangentially involved in arrhythmia. This review surveys the literature on arrhythmia mechanisms from 1965 to the present day, outlines the complex biology underlying potentially each and every rhythm disturbance, and highlights the problems for rational target identification. The rationale for in vivo screening is described and the utility of the zebrafish for this approach and for complementary work in functional genomics is discussed. Current limitations of the model in this setting and the need for careful validation in new disease areas are also described. What the reader will gain An overview of the complex mechanisms underlying most clinical arrhythmias, and insight into the limits of ion channel conductances as drug targets. An introduction to the zebrafish as a model organism, in particular for cardiovascular biology. Potential approaches to overcoming the hurdles to drug discovery in the face of complex biology including in vivo screening of zebrafish genetic disease models. Take home message In vivo screening in faithful disease models allows the effects of drugs on integrative physiology and disease biology to be captured during the screening process, in a manner agnostic to potential drug target or targets. This systematic strategy bypasses current gaps in our understanding of disease biology

  18. Seizures following hippocampal kindling induce QT interval prolongation and increased susceptibility to arrhythmias in rats.

    Science.gov (United States)

    Bealer, Steven L; Little, Jason G

    2013-07-01

    The prolonged seizures of status epilepticus produce chronic arrhythmogenic changes in cardiac function. This study was designed to determine if repeated, self-limiting seizures administered to kindled rats induce similar cardiac dysfunction. Multiple seizures administered to rats following hippocampal kindling resulted in cardiac QT interval prolongation and increased susceptibility to experimental arrhythmias. These data suggest that multiple, self-limiting seizures of intractable epilepsy may have cardiac effects that can contribute to sudden unexpected death in epilepsy (SUDEP).

  19. Serotonin Transporter Promoter Region (5-HTTLPR) Polymorphism Predicts Resting Respiratory Sinus Arrhythmia

    OpenAIRE

    Ellis, Alissa; Beevers, Christopher; Hixon, J. Gregory; McGeary, John E.

    2010-01-01

    Respiratory sinus arrhythmia (RSA) is often conceptualized as an index of physiological flexibility that has been related to emotion regulatory capacity. Although behavioral genetics research indicates that RSA is partly heritable, relatively few molecular genetics studies have been conducted. We examined whether the serotonin transporter promoter region (5-HTTLPR) polymorphism was associated with resting RSA among healthy young adults (N = 71). Short 5-HTTLPR allele carriers had significantl...

  20. Respiratory sinus arrhythmia as a predictor of outcome in major depressive disorder

    OpenAIRE

    Rottenberg, Jonathan; Wilhelm, Frank H.; Gross, James J.; Gotlib, Ian H.

    2002-01-01

    BACKGROUND: Respiratory sinus arrhythmia (RSA) is a noninvasive measure of parasympathetic tone that has been related to emotion regulatory capacity. While some previous work indicates that clinically depressed persons exhibit lower levels of RSA than do normal controls, there is nevertheless considerable between-subject variation in RSA among depressed persons. The current study evaluated the significance of variation in RSA among depressed persons by examining whether levels of RSA predicte...

  1. Late gadolinium enhancement by magnetic resonance explains adverse cardiac events in individuals with ventricular arrhythmia

    International Nuclear Information System (INIS)

    Objective: To determine whether the presence of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR) predict adverse cardiac events in patients with ventricular arrhythmia. Methods: We selected 74 consecutive patients with symptomatic ventricular arrhythmia (premature ventricular contractions and ventricular tachycardia) and left ventricular ejection fraction (LVEF) >55% sent to CMR for evaluation of structural heart disease previously undetected by other complementary methods. LGE, systolic function and volumes of both ventricles were analyzed. At follow-up was assessed a combined end point: hospitalization for ventricular arrhythmia, appropriate implantable cardioverter-defibrillator therapy and cardiac death. Results: During a median follow up of 575 days (interquartile range 24-1120 days) and by analyzing the population according to the presence (n=9, 12%) or not (n=65, 88%) LGE was observed that the group with positive Gd had lower LVEF (58% vs. 66% respectively, p=0.01) and larger volumes (EDV: 185 ml vs. 123 ml respectively, p=0.01 and ESV: 81 ml vs. 42 ml respectively, p=0.01) than the other group. Two (22%) patients in the LGE + group vs. one (4%) of those without LGE showed the combined endpoint (p=0.01) and when performing a logistic regression analysis it was found that the LGE is a predictor of adverse cardiac events analyzed (p=0.029). Conclusions: In this consecutive series of patients with ventricular arrhythmia we demonstrate a strong association between myocardial LGE and adverse cardiac events; this supports the hypothesis that myocardial fibrosis is an important arrhythmogenic substrate. In addition, almost all individuals without LGE were free of events during follow-up suggesting that it is possible to identify through the CMR low-risk individuals who can be treated conservatively. (authors)

  2. Fetal cardiac arrhythmia: antepartum diagnosis of a case of congenital atrial flutter.

    OpenAIRE

    Anderson, K. J.; Simmons, S. C.; Hallidie-Smith, K A

    1981-01-01

    A case of antepartum atrial tachyarrhythmia was detected in the 36th week of pregnancy. Cardiotocograph recordings done twice daily enabled close surveillance of the fetal condition after oxytoxin challenge testing had failed to show evidence of hypoxia. After a diagnosis of fetal cardiac arrhythmia had been made, elective caesarean section in the 40th week of pregnancy resulted in delivery of an infant in atrial flutter and cardiac failure. Both these problems were soon resolved by cardiover...

  3. THE STUDY OF ARRHYTHMIAS FOLLOWING MYOCARDIAL INFARCTION OCCURING WITHIN ONE WEEK

    OpenAIRE

    Sarala.H; Maharudra. S; Gunasheelan

    2012-01-01

    ABSTRACT: OBJECTIVES: Acute myocardial infarction continues to be a major health problem. 50% of deaths with acute myocardial infarction is s aid to occur within first 24 hours after myocardial infarction and is attributed to arrhythm ias. Arrhythmic deaths remain the major cause of death with reduced left ventricular ejecti on fraction or frequent ventricular premature beats. The objective of this study is to assess var ious arrhythmias following myocardial i...

  4. DESIGNING A VIRTUAL MACHINE FOR IDENTIFICATION OF CARDIAC ARRHYTHMIAS USING LAB VIEW

    OpenAIRE

    B. Subha; Subha.S.V; Anitha, M.; M.Eniya; M.Gaayathri

    2013-01-01

    Various projects have been proposed for acquiring and analysis of ECG signals using differentsoftware. To be in advance this work focuses not only on acquiring and analysis of ECG signal but also onidentification of cardiac arrhythmias. This would bridge the gap between medical physicians and engineers.Our project is carried out with the help of LabVIEW software (version 8.2). This model work collects thewaveform from the affected person, analyzed and particular disease is identified. Initial...

  5. Rule Based Identification of Cardiac Arrhythmias from Enhanced ECG Signals Using Multi-Scale PCA

    OpenAIRE

    K. Sharmila; E. Hari Krishna; K. Ashoka Reddy

    2013-01-01

    The detection of abnormal cardiac rhythms, automatic discrimination from rhythmic heart activity, became a thrust area in clinical research. Arrhythmia detection is possible by analyzing the electrocardiogram (ECG) signal features. The presence of interference signals, like power line interference (PLI), Electromyogram (EMG) and baseline drift interferences, could cause serious problems during the recording of ECG signals. Many a time, they pose problem in modern control and signal processing...

  6. Colorectal patients and cardiac arrhythmias detected on the surgical high dependency unit.

    OpenAIRE

    Batra, G. S.; Molyneux, J.; N. A. Scott

    2001-01-01

    INTRODUCTION: Surgical high dependency unit (SHDU) care is becoming an integral feature of colorectal surgical practice. Routine ECG monitoring is a feature of surgical care in this setting. The aim of this study was to determine the incidence and outcome of cardiac arrhythmias detected in an SHDU population of colorectal patients. PATIENTS AND METHODS: 226 patients over a 12 month period were admitted to a 6-bedded SHDU under the care of 3 colorectal surgeons. A total of 29 patients (13%) ha...

  7. Classification of Cardiac Arrhythmia Using WT, HRV, and Fuzzy C-Means Clustering

    OpenAIRE

    A. Dallali, A. Kachouri & M. Samet

    2011-01-01

    The classification of the electrocardiogram registration into different pathologies disease devisesis a complex pattern recognition task. In this paper, we propose a generic feature extraction forclassification of ECG arrhythmias using a fuzzy c-means (FCM) clustering and Heart Ratevariability (HRV). The traditional methods of diagnosis and classification present someinconveniences; seen that the precision of credit note one diagnosis exact depends on thecardiologist experience and the rate c...

  8. The cardiomyocyte molecular clock, regulation of Scn5a, and arrhythmia susceptibility.

    Science.gov (United States)

    Schroder, Elizabeth A; Lefta, Mellani; Zhang, Xiping; Bartos, Daniel C; Feng, Han-Zhong; Zhao, Yihua; Patwardhan, Abhijit; Jin, Jian-Ping; Esser, Karyn A; Delisle, Brian P

    2013-05-15

    The molecular clock mechanism underlies circadian rhythms and is defined by a transcription-translation feedback loop. Bmal1 encodes a core molecular clock transcription factor. Germline Bmal1 knockout mice show a loss of circadian variation in heart rate and blood pressure, and they develop dilated cardiomyopathy. We tested the role of the molecular clock in adult cardiomyocytes by generating mice that allow for the inducible cardiomyocyte-specific deletion of Bmal1 (iCSΔBmal1). ECG telemetry showed that cardiomyocyte-specific deletion of Bmal1 (iCSΔBmal1(-/-)) in adult mice slowed heart rate, prolonged RR and QRS intervals, and increased episodes of arrhythmia. Moreover, isolated iCSΔBmal1(-/-) hearts were more susceptible to arrhythmia during electromechanical stimulation. Examination of candidate cardiac ion channel genes showed that Scn5a, which encodes the principle cardiac voltage-gated Na(+) channel (Na(V)1.5), was circadianly expressed in control mouse and rat hearts but not in iCSΔBmal1(-/-) hearts. In vitro studies confirmed circadian expression of a human Scn5a promoter-luciferase reporter construct and determined that overexpression of clock factors transactivated the Scn5a promoter. Loss of Scn5a circadian expression in iCSΔBmal1(-/-) hearts was associated with decreased levels of Na(V)1.5 and Na(+) current in ventricular myocytes. We conclude that disruption of the molecular clock in the adult heart slows heart rate, increases arrhythmias, and decreases the functional expression of Scn5a. These findings suggest a potential link between environmental factors that alter the cardiomyocyte molecular clock and factors that influence arrhythmia susceptibility in humans.

  9. Acute Effects of Fine Particulate Air Pollution on Cardiac Arrhythmia: The APACR Study

    OpenAIRE

    He, Fan; Michele L. Shaffer; Rodriguez-Colon, Sol; Yanosky, Jeff D.; Bixler, Edward; Cascio, Wayne E; Liao, Duanping

    2011-01-01

    Background: The mechanisms underlying the relationship between particulate matter (PM) air pollution and cardiac disease are not fully understood. Objectives: We examined the effects and time course of exposure to fine PM [aerodynamic diameter ≤ 2.5 μm (PM2.5)] on cardiac arrhythmia in 105 middle-age community-dwelling healthy nonsmokers in central Pennsylvania. Methods: The 24-hr beat-to-beat electrocardiography data were obtained using a high-resolution Holter system. After visually identif...

  10. Automatic recognition of cardiac arrhythmias based on the geometric patterns of Poincaré plots

    International Nuclear Information System (INIS)

    The Poincaré plot emerges as an effective tool for assessing cardiovascular autonomic regulation. It displays nonlinear characteristics of heart rate variability (HRV) from electrocardiographic (ECG) recordings and gives a global view of the long range of ECG signals. In the telemedicine or computer-aided diagnosis system, it would offer significant auxiliary information for diagnosis if the patterns of the Poincaré plots can be automatically classified. Therefore, we developed an automatic classification system to distinguish five geometric patterns of the Poincaré plots from four types of cardiac arrhythmias. The statistics features are designed on measurements and an ensemble classifier of three types of neural networks is proposed. Aiming at the difficulty to set a proper threshold for classifying the multiple categories, the threshold selection strategy is analyzed. 24 h ECG monitoring recordings from 674 patients, which have four types of cardiac arrhythmias, are adopted for recognition. For comparison, Support Vector Machine (SVM) classifiers with linear and Gaussian kernels are also applied. The experiment results demonstrate the effectiveness of the extracted features and the better performance of the designed classifier. Our study can be applied to diagnose the corresponding sinus rhythm and arrhythmia substrates disease automatically in the telemedicine and computer-aided diagnosis system. (paper)

  11. An arrhythmia classification algorithm using a dedicated wavelet adapted to different subjects

    Directory of Open Access Journals (Sweden)

    Min Se Dong

    2011-06-01

    Full Text Available Abstract Background Numerous studies have been conducted regarding a heartbeat classification algorithm over the past several decades. However, many algorithms have also been studied to acquire robust performance, as biosignals have a large amount of variation among individuals. Various methods have been proposed to reduce the differences coming from personal characteristics, but these expand the differences caused by arrhythmia. Methods In this paper, an arrhythmia classification algorithm using a dedicated wavelet adapted to individual subjects is proposed. We reduced the performance variation using dedicated wavelets, as in the ECG morphologies of the subjects. The proposed algorithm utilizes morphological filtering and a continuous wavelet transform with a dedicated wavelet. A principal component analysis and linear discriminant analysis were utilized to compress the morphological data transformed by the dedicated wavelets. An extreme learning machine was used as a classifier in the proposed algorithm. Results A performance evaluation was conducted with the MIT-BIH arrhythmia database. The results showed a high sensitivity of 97.51%, specificity of 85.07%, accuracy of 97.94%, and a positive predictive value of 97.26%. Conclusions The proposed algorithm achieves better accuracy than other state-of-the-art algorithms with no intrasubject between the training and evaluation datasets. And it significantly reduces the amount of intervention needed by physicians.

  12. Efficient ECG signal analysis using wavelet technique for arrhythmia detection: an ANFIS approach

    Science.gov (United States)

    Khandait, P. D.; Bawane, N. G.; Limaye, S. S.

    2010-02-01

    This paper deals with improved ECG signal analysis using Wavelet Transform Techniques and employing subsequent modified feature extraction for Arrhythmia detection based on Neuro-Fuzzy technique. This improvement is based on suitable choice of features in evaluating and predicting life threatening Ventricular Arrhythmia . Analyzing electrocardiographic signals (ECG) includes not only inspection of P, QRS and T waves, but also the causal relations they have and the temporal sequences they build within long observation periods. Wavelet-transform is used for effective feature extraction and Adaptive Neuro-Fuzzy Inference System (ANFIS) is considered for the classifier model. In a first step, QRS complexes are detected. Then, each QRS is delineated by detecting and identifying the peaks of the individual waves, as well as the complex onset and end. Finally, the determination of P and T wave peaks, onsets and ends is performed. We evaluated the algorithm on several manually annotated databases, such as MIT-BIH Arrhythmia and CSE databases, developed for validation purposes. Features based on the ECG waveform shape and heart beat intervals are used as inputs to the classifiers. The performance of the ANFIS model is evaluated in terms of training performance and classification accuracies and the results confirmed that the proposed ANFIS model has potential in classifying the ECG signals. Cross validation is used to measure the classifier performance. A testing classification accuracy of 95.13% is achieved which is a significant improvement.

  13. Genetic testing and genetic counseling in patients with sudden death risk due to heritable arrhythmias.

    Science.gov (United States)

    Spoonamore, Katherine G; Ware, Stephanie M

    2016-03-01

    Sudden cardiac death due to heritable ventricular arrhythmias is an important cause of mortality, especially in young healthy individuals. The identification of the genetic basis of Mendelian diseases associated with arrhythmia has allowed the integration of this information into the diagnosis and clinical management of patients and at-risk family members. The rapid expansion of genetic testing options and the increasing complexity involved in the interpretation of results creates unique opportunities and challenges. There is a need for competency to incorporate genetics into clinical management and to provide appropriate family-based risk assessment and information. In addition, disease-specific genetic knowledge is required to order and correctly interpret and apply genetic testing results. Importantly, genetic diagnosis has a critical role in the risk stratification and clinical management of family members. This review summarizes the approach to genetic counseling and genetic testing for inherited arrhythmias and highlights specific genetic principles that apply to long QT syndrome, short QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia.

  14. [On evaluating occupational fitness in railway workers with ventricular arrhythmias after coronary arteries stenting].

    Science.gov (United States)

    Muraseyeva, E V; Gorokhova, S G; Prigorovskaya, T S; Pfaf, V F

    2016-01-01

    The authors studied prospects of work capacity preserving after coronary stenting in IHD and cardiac arrhythmias. Examination covered 158 railway workers underwent complete endovascular revascularization of myocardium for coronary stenosis; all of them had ventricular arrhythmias before coronary surgery. Findings are that in long-term period (in 16 months in average) after coronary stenting, grade I and III ventricular extrasystoles disappeared in 77.8 and 54.5% of cases respectively, but only in 11.9% of grade IV ventricular extrasystoles cases. Ventricular extrasystoles remained unchanged in 44.3% of cases. Reliable relationships were seen between unchanged grade IV ventricular extrasystoles and body weight index (OR = 5.49, 95% CI: 0.87-34.67), general cholesterol level (OR = 1.69; 95% CI: 1.06-2.69), low density lipoproteins (OR = 1.66; 95% CI: 1.00-2.76) and left ventricular ejection function lower 45% (OR = 1.61; 95% CI: 1.14-2.27), exertion ventricular extrasystoles before myocardium revascularization (OR = 3.1; 95% CI: 1.78-5.41). That necessitates correction of the mentioned risk factors of cardiac arrhythmias for restored work capacity.

  15. Exercise-induced protection against reperfusion arrhythmia involves stabilization of mitochondrial energetics.

    Science.gov (United States)

    Alleman, Rick J; Tsang, Alvin M; Ryan, Terence E; Patteson, Daniel J; McClung, Joseph M; Spangenburg, Espen E; Shaikh, Saame Raza; Neufer, P Darrell; Brown, David A

    2016-05-15

    Mitochondria influence cardiac electrophysiology through energy- and redox-sensitive ion channels in the sarcolemma, with the collapse of energetics believed to be centrally involved in arrhythmogenesis. This study was conducted to determine if preservation of mitochondrial membrane potential (ΔΨm) contributes to the antiarrhythmic effect of exercise. We utilized perfused hearts, isolated myocytes, and isolated mitochondria exposed to metabolic challenge to determine the effects of exercise on cardiac mitochondria. Hearts from sedentary (Sed) and exercised (Ex; 10 days of treadmill running) Sprague-Dawley rats were perfused on a two-photon microscope stage for simultaneous measurement of ΔΨm and ECG. After ischemia-reperfusion, the collapse of ΔΨm was commensurate with the onset of arrhythmia. Exercise preserved ΔΨm and decreased the incidence of fibrillation/tachycardia (P hypoxia-reoxygenation, with Ex rats demonstrating enhanced redox control and sustained ΔΨm during reoxygenation. Finally, we induced anoxia-reoxygenation in isolated mitochondria using high-resolution respirometry with simultaneous measurement of respiration and H2O2 Mitochondria from Ex rats sustained respiration with lower rates of H2O2 emission than Sed rats. Exercise helps sustain postischemic mitochondrial bioenergetics and redox homeostasis, which is associated with preserved ΔΨm and protection against reperfusion arrhythmia. The reduction of fatal ventricular arrhythmias through exercise-induced mitochondrial adaptations indicates that mitochondrial therapeutics may be an effective target for the treatment of heart disease. PMID:26945082

  16. Frequency of cardiac arrhythmias in high and low- yielding dairy cows

    Directory of Open Access Journals (Sweden)

    Afshin Jafari Dehkordi

    2014-06-01

    Full Text Available Electrocardiography (ECG may be used to recognize cardiac disorders. Levels of milk production may change the serum electrolytes which its imbalance has a role in cardiac arrhythmia. Fifty high yielding and fifty low yielding Holstein dairy cows were used in this study. Electrocardiography was recorded by base-apex lead and blood samples were collected from jugular vein for measurement of serum elements such as sodium, potassium, calcium, phosphorous, iron and magnesium. Cardiac dysrhythmias were detected more frequent in low yielding Holstein cows (62.00% compared to high yielding Holstein cows (46.00%. The cardiac dysrhythmias that were observed in low yielding Holstein cows included sinus arrhythmia (34.70%, wandering pacemaker (22.45 %, bradycardia (18.37%, tachycardia (10.20%, atrial premature beat (2.04%, sinoatrial block (2.04%, atrial fibrillation (8.16% and atrial tachycardia (2.04%. The cardiac dysrhythmias were observed in high yielding Holstein cows including, sinus arrhythmia (86.95% and wandering pacemaker (13.05%. Also, notched P wave was observed to be 30% and 14% in high- and low- yielding Holstein cows respectively. The serum calcium concentration of low yielding Holstein cows was significantly lower than that of high yielding Holstein cows. There was not any detectable significant difference in other serum elements between high- and low- yielding Holstein cows. Based on the result of present study, could be concluded that low serum concentration of calcium results to more frequent dysrhythmias in low yielding Holstein cows.

  17. Symmetrical compression distance for arrhythmia discrimination in cloud-based big-data services.

    Science.gov (United States)

    Lillo-Castellano, J M; Mora-Jiménez, I; Santiago-Mozos, R; Chavarría-Asso, F; Cano-González, A; García-Alberola, A; Rojo-Álvarez, J L

    2015-07-01

    The current development of cloud computing is completely changing the paradigm of data knowledge extraction in huge databases. An example of this technology in the cardiac arrhythmia field is the SCOOP platform, a national-level scientific cloud-based big data service for implantable cardioverter defibrillators. In this scenario, we here propose a new methodology for automatic classification of intracardiac electrograms (EGMs) in a cloud computing system, designed for minimal signal preprocessing. A new compression-based similarity measure (CSM) is created for low computational burden, so-called weighted fast compression distance, which provides better performance when compared with other CSMs in the literature. Using simple machine learning techniques, a set of 6848 EGMs extracted from SCOOP platform were classified into seven cardiac arrhythmia classes and one noise class, reaching near to 90% accuracy when previous patient arrhythmia information was available and 63% otherwise, hence overcoming in all cases the classification provided by the majority class. Results show that this methodology can be used as a high-quality service of cloud computing, providing support to physicians for improving the knowledge on patient diagnosis.

  18. [Pertinence of animal and human models in the evaluation of ventricular anti-arrhythmia agents].

    Science.gov (United States)

    Funck-Brentano, C; Le Heuzey, J Y

    1991-02-01

    The development of antiarrhythmic agents for the treatment of ventricular arrhythmias depends to a large extent on their effects in different animal and human models. The clinical relevance of the data so obtained is debatable. Firstly, in vitro animal models of arrhythmias are not very predictive of the multiple clinical forms of ventricular arrhythmias. Secondly, the intermediary criteria of evaluation of the effects of antiarrhythmic drugs in humans are generally not valid in terms of criteria of substitution for the evaluation of therapeutic effects. Nevertheless, cellular and hemodynamic studies of the electrophysiological properties of drugs are essential for correct clinical usage of antiarrhythmics. They help predict the principal clinical electrocardiographic changes and their modulation with respect to parameters such as ischemia or heart rate, their hemodynamic tolerance and certain undesirable, especially proarrhythmic, effects. However, the clinical pertinence of these studies remains limited for a number of reasons. In particular, most antiarrhythmic agents have multiple electrophysiological effects, the resultant of which is difficult to predict in the clinical situation. In addition, many of these drugs have active metabolites, the formation of which varies from person to person, which also reduces the clinical relevance of studies of the parent molecule alone. Clinical trials in appropriate patient populations should therefore be preferred to the multiplication of studies on experimental models of uncertain relevance.

  19. Classification of Cardiac Arrhythmia Using WT, HRV, and Fuzzy C-Means Clustering

    Directory of Open Access Journals (Sweden)

    A. Dallali, A. Kachouri & M. Samet

    2011-08-01

    Full Text Available The classification of the electrocardiogram registration into different pathologies disease devisesis a complex pattern recognition task. In this paper, we propose a generic feature extraction forclassification of ECG arrhythmias using a fuzzy c-means (FCM clustering and Heart Ratevariability (HRV. The traditional methods of diagnosis and classification present someinconveniences; seen that the precision of credit note one diagnosis exact depends on thecardiologist experience and the rate concentration. Due to the high mortality rate of heartdiseases, early detection and precise discrimination of ECG arrhythmia is essential for thetreatment of patients. During the recording of ECG signal, different forms of noise can besuperimposed in the useful signal. The pre-treatment of ECG imposes the suppression of theseperturbation signals. The row date is preprocessed, normalized and then data points areclustered using FCM technique.In this work, four different structures, FCM-HRV, PCM-HRV, FCMC-HRV and FPCM-HRV areformed by using heart rate variability technique and fuzzy c-means clustering. In addition, FCMHRVis the new method proposed for classification of ECG.This paper presents a comparative study of the classification accuracy of ECG signals by usingthese four structures for computationally efficient diagnosis. The ECG signals taken from MIT-BIHECG database are used in training to classify 4 different arrhythmias (Atrial FibrillationTermination.All of the structures are tested by using the same ECG records. The test results suggest thatFCMC-HRV structure can generalize better and is faster than the other structures.

  20. Automatic recognition of cardiac arrhythmias based on the geometric patterns of Poincaré plots.

    Science.gov (United States)

    Zhang, Lijuan; Guo, Tianci; Xi, Bin; Fan, Yang; Wang, Kun; Bi, Jiacheng; Wang, Ying

    2015-02-01

    The Poincaré plot emerges as an effective tool for assessing cardiovascular autonomic regulation. It displays nonlinear characteristics of heart rate variability (HRV) from electrocardiographic (ECG) recordings and gives a global view of the long range of ECG signals. In the telemedicine or computer-aided diagnosis system, it would offer significant auxiliary information for diagnosis if the patterns of the Poincaré plots can be automatically classified. Therefore, we developed an automatic classification system to distinguish five geometric patterns of the Poincaré plots from four types of cardiac arrhythmias. The statistics features are designed on measurements and an ensemble classifier of three types of neural networks is proposed. Aiming at the difficulty to set a proper threshold for classifying the multiple categories, the threshold selection strategy is analyzed. 24 h ECG monitoring recordings from 674 patients, which have four types of cardiac arrhythmias, are adopted for recognition. For comparison, Support Vector Machine (SVM) classifiers with linear and Gaussian kernels are also applied. The experiment results demonstrate the effectiveness of the extracted features and the better performance of the designed classifier. Our study can be applied to diagnose the corresponding sinus rhythm and arrhythmia substrates disease automatically in the telemedicine and computer-aided diagnosis system. PMID:25582837

  1. Family and population strategies for screening and counselling of inherited cardiac arrhythmias.

    Science.gov (United States)

    van Langen, I M; Hofman, N; Tan, H L; Wilde, A A M

    2004-01-01

    Family screening in inherited cardiac arrhythmias has been performed in The Netherlands since 1996, when diagnostic DNA testing in long QT syndrome (LQTS) and hypertrophic cardiomyopathy (HCM) became technically possible. In multidisciplinary outpatient academic clinics, an adjusted protocol for genetic counselling, originally derived from predictive testing in Huntington's disease, is being used. 1110 individuals, including 842 relatives of index patients, were informed about their risks, and most were tested molecularly and/or clinically for carriership of the disease present in their family. Of 345 relatives who were referred for cardiologic follow-up, 189 are being treated, because of an increased risk of life-threatening arrhythmias. Evaluation of the psychological and social consequences of family screening for inherited arrhythmias can be performed by using the adapted criteria of Wilson and Jüngner, i.e., from a point of view of public health. Preliminary results of psychological research show that parents of children at risk for LQTS show high levels of distress. Many other aspects have to be evaluated yet, making final conclusions about the feasibility of family screening difficult, particularly in HCM. Clinical guidelines are urgently needed. Population screening by molecular testing, for instance in athletic preparticipation screening, will become possible in the future and has its own prerequisites for success. PMID:15176433

  2. Influence of ambient temperature and diurnal temperature range on incidence of cardiac arrhythmias

    Science.gov (United States)

    Kim, Jayeun; Kim, Ho

    2016-08-01

    We investigated the association between ambient temperature and diurnal temperature range (DTR) and the exacerbation of arrhythmia symptoms, using data from 31,629 arrhythmia-related emergency department (ED) visits in Seoul, Korea. Linear regression analyses with allowances for over-dispersion were applied to temperature variables and ED visits, adjusted for various environmental factors. The effects were expressed as percentage changes in the risk of arrhythmia-related ED visits up to 5 days later, with 95 % confidence intervals (CI), per 1 °C increase in DTR and 1 °C decrease in mean temperature. The overall risk of ED visits increased by 1.06 % (95 % CI 0.39 %, 1.73 %) for temperature and by 1.84 % (0.34, 3.37 %) for DTR. A season-specific effect was detected for temperature during both fall (1.18 % [0.01, 2.37 %]) and winter (0.87 % [0.07, 1.67 %]), and for DTR during spring (3.76 % [0.34, 7.29 %]). Females were more vulnerable, with 1.57 % [0.56, 2.59 %] and 3.84 % [1.53, 6.20 %] for the changes in temperature and DTR, respectively. An age-specific effect was detected for DTR, with 3.13 % [0.95, 5.36 %] for age ≥ 65 years, while a greater increased risk with temperature decrease was observed among those aged <65 (1.08 % [0.17, 2.00 %]) than among those aged ≥65 (1.02 % [0.06, 1.99 %]). Cardiac arrest was inversely related with temperature (1.61 % [0.46, 2.79 %]), while other cardiac arrhythmias depended more on the change in DTR (4.72 % [0.37, 9.26 %]). These findings provide evidence that low-temperature and elevated DTR influence the occurrence of arrhythmia exacerbations or symptoms, suggesting a possible strategy for reducing risk by encouraging vulnerable populations to minimize exposure.

  3. RIESGO DE ARRITMIAS E HIPERTENSIÓN ARTERIAL / Risk of Arrhythmias and hypertension

    Directory of Open Access Journals (Sweden)

    Raimundo Carmona Puerta

    2012-03-01

    the development of arrhythmias in hypertensive patients. The presence of ventricular arrhythmias, from premature ventricular complexes to ventricular tachycardia, has been shown in a 10 to 27% of affected patients, a percentage that decreases with the severity of the arrhythmia. Noninvasive risk markers for ventricular arrhythmias have been summarized as follows: dispersion and variability of the QT interval, presence of late potentials, heart rate variability, abnormal morphology and T-wave alternans. All of these are related to anatomic-structural changes of the ventricular wall, which affect the action potential. The importance of knowing the epidemiology, pathophysiology, and noninvasive risk markers for arrhythmias in hypertensive patients, offers a way for the application of the proper therapeutic in the control of blood pressure and regression of hypertrophy, as has been shown by inhibitor drugs of the renin-angiotensin-aldosterone system, which decrease the risk of arrhythmias.

  4. Inflammation markers are associated with metabolic syndrome and ventricular arrhythmia in patients with coronary artery disease

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    Krzysztof Safranow

    2016-02-01

    Full Text Available Background: Inflammation plays a major role in the development and progression of atherosclerosis and coronary artery disease (CAD. Inflammation markers, including white blood cell (WBC count, C-reactive protein (CRP and interleukin-6 (IL-6, are widely used for cardiovascular risk prediction. The aim of the study was to establish factors associated with WBC, CRP and IL-6 in patients with CAD. Two functional polymorphisms in genes encoding enzymes participating in adenosine metabolism were analyzed (C34T AMPD1, G22A ADA. Methods: Plasma concentrations of IL-6 were measured using high-sensitivity ELISA kits, and the nephelometric method was used for high-sensitivity CRP (hs-CRP measurement in 167 CAD patients. Results: Presence of metabolic syndrome (MS and its components, presence of heart failure, severity of CAD symptoms, severe past ventricular arrhythmia (sustained ventricular tachycardia [sVT] or ventricular fibrillation [VF], lower left ventricle ejection fraction, higher left ventricle mass index, higher end-diastolic volume and higher number of smoking pack-years were significantly associated with higher WBC, CRP and IL-6. Strong associations with arrhythmia were observed for IL-6 (median 3.90 vs 1.89 pg/mL, p<0.00001 and CRP concentration (6.32 vs 1.47 mg/L, p=0.00009, while MS was associated most strongly with IL-6. CRP and IL-6 were independent markers discriminating patients with sVT or VF. There were no associations between AMPD1 or ADA genotypes and inflammation markers. Conclusions: WBC, CRP and IL-6 are strongly associated with components of the metabolic syndrome. Their strong association with life-threatening ventricular arrhythmia emphasizes the proarrhythmic role of inflammation in the increased cardiovascular risk of CAD patients.

  5. Rule Based Identification of Cardiac Arrhythmias from Enhanced ECG Signals Using Multi-Scale PCA

    Directory of Open Access Journals (Sweden)

    K. Sharmila

    2013-09-01

    Full Text Available The detection of abnormal cardiac rhythms, automatic discrimination from rhythmic heart activity, became a thrust area in clinical research. Arrhythmia detection is possible by analyzing the electrocardiogram (ECG signal features. The presence of interference signals, like power line interference (PLI, Electromyogram (EMG and baseline drift interferences, could cause serious problems during the recording of ECG signals. Many a time, they pose problem in modern control and signal processing applications by being narrow in-band interference near the frequencies carrying crucial information. This paper presents an approach for ECG signal enhancement by combining the attractive properties of principal component analysis (PCA and wavelets, resulting in multi-scale PCA. In Multi-Scale Principal Component Analysis (MSPCA, the PCA’s ability to decorrelate the variables by extracting a linear relationship and wavelet analysis are utilized. MSPCA method effectively processed the noisy ECG signal and enhanced signal features are used for clear identification of arrhythmias. In MSPCA, the principal components of the wavelet coefficients of the ECG data at each scale are computed first and are then combined at relevant scales. Statistical measures computed in terms of root mean square deviation (RMSD, root mean square error (RMSE, root mean square variation (RMSV and improvement in signal to noise ratio (SNRI revealed that the Daubechies based MSPCA outperformed the basic wavelet based processing for ECG signal enhancement. With enhanced signal features obtained after MSPCA processing, the detectable measures, QRS duration and R-R interval are evaluated. By using the rule base technique, projecting the detectable measures on a two dimensional area, various arrhythmias are detected depending upon the beat falling into particular place of the two dimensional area.

  6. Bile acid-induced arrhythmia is mediated by muscarinic M2 receptors in neonatal rat cardiomyocytes.

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    Siti H Sheikh Abdul Kadir

    Full Text Available BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP is a common disease affecting up to 5% of pregnancies and which can cause fetal arrhythmia and sudden intrauterine death. We previously demonstrated that bile acid taurocholate (TC, which is raised in the bloodstream of ICP, can acutely alter the rate and rhythm of contraction and induce abnormal calcium destabilization in cultured neonatal rat cardiomyocytes (NRCM. Apart from their hepatic functions bile acids are ubiquitous signalling molecules with diverse systemic effects mediated by either the nuclear receptor FXR or by a recently discovered G-protein coupled receptor TGR5. We aim to investigate the mechanism of bile-acid induced arrhythmogenic effects in an in-vitro model of the fetal heart. METHODS AND RESULTS: Levels of bile acid transporters and nuclear receptor FXR were studied by quantitative real time PCR, western blot and immunostaining, which showed low levels of expression. We did not observe functional involvement of the canonical receptors FXR and TGR5. Instead, we found that TC binds to the muscarinic M(2 receptor in NRCM and serves as a partial agonist of this receptor in terms of inhibitory effect on intracellular cAMP and negative chronotropic response. Pharmacological inhibition and siRNA-knockdown of the M(2 receptor completely abolished the negative effect of TC on contraction, calcium transient amplitude and synchronisation in NRCM clusters. CONCLUSION: We conclude that in NRCM the TC-induced arrhythmia is mediated by the partial agonism at the M(2 receptor. This mechanism might serve as a promising new therapeutic target for fetal arrhythmia.

  7. Functional reentry and circus movement arrhythmias in the small intestine of normal and diabetic rats.

    Science.gov (United States)

    Lammers, Wim J E P; Stephen, B; Karam, S M

    2012-04-01

    In a few recent studies, the presence of arrhythmias based on reentry and circus movement of the slow wave have been shown to occur in normal and diseased stomachs. To date, however, reentry has not been demonstrated before in any other part of the gastrointestinal system. No animals had to be killed for this study. Use was made of materials obtained during the course of another study in which 11 rats were treated with streptozotocin and housed with age-matched controls. After 3 and 7 mo, segments of duodenum, jejunum, and ileum were isolated and positioned in a tissue bath. Slow wave propagation was recorded with 121 extracellular electrodes. After the experiment, the propagation of the slow waves was reconstructed. In 10 of a total of 66 intestinal segments (15%), a circus movement of the slow wave was detected. These reentries were seen in control (n = 2) as well as in 3-mo (n = 2) and 7-mo (n = 6) diabetic rats. Local conduction velocities and beat-to-beat intervals during the reentries were measured (0.42 ± 0.15 and 3.03 ± 0.67 cm/s, respectively) leading to a wavelength of 1.3 ± 0.5 cm and a circuit diameter of 4.1 ± 1.5 mm. This is the first demonstration of a reentrant arrhythmia in the small intestine of control and diabetic rats. Calculations of the size of the circuits indicate that they are small enough to fit inside the intestinal wall. Extrapolation based on measured velocities and rates indicate that reentrant arrhythmias are also possible in the distal small intestine of larger animals including humans.

  8. Induced pluripotent stem cell derived cardiomyocytes as models for cardiac arrhythmias

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    Maaike eHoekstra

    2012-08-01

    Full Text Available Cardiac arrhythmias are a major cause of morbidity and mortality. In younger patients, the majority of sudden cardiac deaths have an underlying Mendelian genetic cause. Over the last 15 years, enormous progress has been made in identifying the distinct clinical phenotypes and in studying the basic cellular and genetic mechanisms associated with the primary Mendelian (monogenic arrhythmia syndromes. Investigation of the electrophysiological consequences of an ion channel mutation is ideally done in the native cardiomyocyte environment. However, the majority of such studies so far have relied on heterologous expression systems in which single ion channel genes are expressed in non-cardiac cells. In some cases, transgenic mouse models haven been generated, but these also have significant shortcomings, primarily related to species differences.The discovery that somatic cells can be reprogrammed to pluripotency as induced pluripotent stem cells (iPSC has generated much interest since it presents an opportunity to generate patient- and disease-specific cell lines from which normal and diseased human cardiomyocytes can be obtained These genetically diverse human model systems can be studied in vitro and used to decipher mechanisms of disease and identify strategies and reagents for new therapies. Here we review the present state of the art with respect to cardiac disease models already generated using IPSC technology and which have been (partially characterized.Human iPSC (hiPSC models have been described for the cardiac arrhythmia syndromes, including LQT1, LQT2, LQT3-Brugada Syndrome, LQT8/Timothy syndrome and catecholaminergic polymorphic ventricular tachycardia. In most cases, the hiPSC-derived cardiomyoctes recapitulate the disease phenotype and have already provided opportunities for novel insight into cardiac pathophysiology. It is expected that the lines will be useful in the development of pharmacological agents for the management of these

  9. Facilitating arrhythmia simulation: the method of quantitative cellular automata modeling and parallel running

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    Mondry Adrian

    2004-08-01

    Full Text Available Abstract Background Many arrhythmias are triggered by abnormal electrical activity at the ionic channel and cell level, and then evolve spatio-temporally within the heart. To understand arrhythmias better and to diagnose them more precisely by their ECG waveforms, a whole-heart model is required to explore the association between the massively parallel activities at the channel/cell level and the integrative electrophysiological phenomena at organ level. Methods We have developed a method to build large-scale electrophysiological models by using extended cellular automata, and to run such models on a cluster of shared memory machines. We describe here the method, including the extension of a language-based cellular automaton to implement quantitative computing, the building of a whole-heart model with Visible Human Project data, the parallelization of the model on a cluster of shared memory computers with OpenMP and MPI hybrid programming, and a simulation algorithm that links cellular activity with the ECG. Results We demonstrate that electrical activities at channel, cell, and organ levels can be traced and captured conveniently in our extended cellular automaton system. Examples of some ECG waveforms simulated with a 2-D slice are given to support the ECG simulation algorithm. A performance evaluation of the 3-D model on a four-node cluster is also given. Conclusions Quantitative multicellular modeling with extended cellular automata is a highly efficient and widely applicable method to weave experimental data at different levels into computational models. This process can be used to investigate complex and collective biological activities that can be described neither by their governing differentiation equations nor by discrete parallel computation. Transparent cluster computing is a convenient and effective method to make time-consuming simulation feasible. Arrhythmias, as a typical case, can be effectively simulated with the methods

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

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    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.

  11. Genome-wide association of implantable cardioverter-defibrillator activation with life-threatening arrhythmias.

    Directory of Open Access Journals (Sweden)

    Sarah S Murray

    Full Text Available OBJECTIVES: To identify genetic factors that would be predictive of individuals who require an implantable cardioverter-defibrillator (ICD, we conducted a genome-wide association study among individuals with an ICD who experienced a life-threatening arrhythmia (LTA; cases vs. those who did not over at least a 3-year period (controls. BACKGROUND: Most individuals that receive implantable cardioverter-defibrillators never experience a life-threatening arrhythmia. Genetic factors may help identify who is most at risk. METHODS: Patients with an ICD and extended follow-up were recruited from 34 clinical sites with the goal of oversampling those who had experienced LTA, with a cumulative 607 cases and 297 controls included in the analysis. A total of 1,006 Caucasian patients were enrolled during a time period of 13 months. Arrhythmia status of 904 patients could be confirmed and their genomic data were included in the analysis. In this cohort, there were 704 males, 200 females, and the average age was 73.3 years. We genotyped DNA samples using the Illumina Human660 W Genotyping BeadChip and tested for association between genotype at common variants and the phenotype of having an LTA. RESULTS AND CONCLUSIONS: We did not find any associations reaching genome-wide significance, with the strongest association at chromosome 13, rs11856574 at P = 5×10⁻⁶. Loci previously implicated in phenotypes such as QT interval (measure of the time between the start of the Q wave and the end of the T wave as measured by electrocardiogram were not found to be significantly associated with having an LTA. Although powered to detect such associations, we did not find common genetic variants of large effect associated with having a LTA in those of European descent. This indicates that common gene variants cannot be used at this time to guide ICD risk-stratification. TRIAL REGISTRATION: ClinicalTrials.gov NCT00664807.

  12. Outcomes among athletes with arrhythmias and electrocardiographic abnormalities: implications for ECG interpretation.

    Science.gov (United States)

    McClaskey, David; Lee, Daniel; Buch, Eric

    2013-10-01

    Electrocardiographic (ECG) aberrations and arrhythmias occur frequently among athletes due to normal variants, subclinical cardiac disease or structural and electrical remodeling in response to training. It is unclear whether these changes are associated with adverse clinical outcomes over time among otherwise asymptomatic, healthy athletes. Consensus guidelines have been developed to guide the clinician regarding further management of these arrhythmias. The purpose of this review is to summarize prospective data regarding cardiovascular outcomes related to ECG changes among athletes and compare these findings with current guidelines. A review of the literature was conducted using the PubMed database (1966--present). Outcomes of interest included documented cardiac symptoms or events, such as episodes of cardiac or cerebral hypoperfusion, sudden death or prophylactic procedural interventions. Studies were included for analysis if they involved (1) athletes with documented, baseline arrhythmias and/or abnormal ECG variations; (2) a study design with longitudinal follow-up (designated as >1 month, to exclude short-term Holter studies); and (3) outcomes that include documented cardiac symptoms or events. A total of 33 studies met the above criteria, encompassing over 4,200 athletes, with follow-up ranging from 2 months to 14.6 years. There were few adverse outcomes among cases of sinus bradycardia >30 bpm, sinus pauses sports eligibility. Findings in this review are limited by a lack of control groups, limited assessment of confounding factors (such as performance-enhancing drugs), and under-representation of women and certain ethnicities. Further prospective studies are needed to better characterize the long-term outcome of ECG abnormalities among athletes and provide evidence for ECG interpretation guidelines. PMID:23852445

  13. Epicardial radiofrequency ablation for left ventricular aneurysm related ventricular arrhythmias during off-pump coronary artery bypass surgery

    Institute of Scientific and Technical Information of China (English)

    YU Yang; GAO Ming-xin; LI Hai-tao; ZHANG Fan; GU Cheng-xiong

    2012-01-01

    Background Left ventricular aneurysm (LVA) is one of the serious complications after acute myocardial infarction.We attempted to evaluate the preliminary efficacy of LVA repair combined with epicardial radiofrequency ablation for ventricular arrhythmia during off-pump coronary artery bypass grafting (OPCAB).Methods From June 2009 to April 2011,31 patients with LVA had angina symptoms and ventricular arrhythmia.In all patients,circular and cross-shaped radiofrequency epicardial ablations were performed using unipolar ablation pen along the border between the aneurysm wall and normal cardiac tissue and in the central zone of the aneurysms,followed by a linear placation of ventricular aneurysms on beating heart.Results All the patients showed complete recovery.The average number of grafted vessels was 2.7±1.3.Intraoperative examinations revealed that the ventricular arrhythmia was effectively controlled by radiofrequency ablation.All cases had been followed up for one year.Holter monitoring revealed a significant reduction in ventricular arrhythmias (P <0.05).Echocardiography showed significant increase in left ventricular ejection fraction (P <0.05) and decrease in left ventricular end-diastolic diameter (P <0.05).Conclusions For patients with ventricular aneurysm and preoperative malignant arrhythmia,aneurysm repair plus epicardial radiofrequency ablation in OPCAB was found to be an effective and feasible therapeutic technique.However,medium-to long-term therapeutic efficacy of this method remains to be determined by future studies and observations.

  14. Arctigenin, a Potential Anti-Arrhythmic Agent, Inhibits Aconitine-Induced Arrhythmia by Regulating Multi-Ion Channels

    Directory of Open Access Journals (Sweden)

    Zhenying Zhao

    2013-11-01

    Full Text Available Background/Aims: Arctigenin possesses biological activities, but its underlying mechanisms at the cellular and ion channel levels are not completely understood. Therefore, the present study was designed to identify the anti-arrhythmia effect of arctigenin in vivo, as well as its cellular targets and mechanisms. Methods: A rat arrhythmia model was established via continuous aconitine infusion, and the onset times of ventricular premature contraction, ventricular tachycardia and death were recorded. The Action Potential Duration (APD, sodium current (INa, L-type calcium current (ICa, L and transient outward potassium current (Ito were measured and analysed using a patch-clamp recording technique in normal rat cardiomyocytes and myocytes of arrhythmia aconitine-induced by. Results: Arctigenin significantly delayed the arrhythmia onset in the aconitine-induced rat model. The 50% and 90% repolarisations (APD50 and APD90 were shortened by 100 µM arctigenin; the arctigenin dose also inhibited the prolongation of APD50 and APD90 caused by 1 µM aconitine. Arctigenin inhibited INa and ICa,L and attenuated the aconitine-increased INa and ICa,L by accelerating the activation process and delaying the inactivation process. Arctigenin enhanced Ito by facilitating the activation process and delaying the inactivation process, and recoverd the decreased Ito induced by aconitine. Conclusions: Arctigenin has displayed anti-arrhythmia effects, both in vivo and in vitro. In the context of electrophysiology, INa, ICa, L, and Ito may be multiple targets of arctigenin, leading to its antiarrhythmic effect.

  15. High level of oxygen treatment causes cardiotoxicity with arrhythmias and redox modulation

    Energy Technology Data Exchange (ETDEWEB)

    Chapalamadugu, Kalyan C.; Panguluri, Siva K. [Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL (United States); Bennett, Eric S. [Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL (United States); Kolliputi, Narasaiah [Division of Allergy and Immunology, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL (United States); Tipparaju, Srinivas M., E-mail: stippara@health.usf.edu [Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL (United States)

    2015-01-01

    Hyperoxia exposure in mice leads to cardiac hypertrophy and voltage-gated potassium (Kv) channel remodeling. Because redox balance of pyridine nucleotides affects Kv function and hyperoxia alters cellular redox potential, we hypothesized that hyperoxia exposure leads to cardiac ion channel disturbances and redox changes resulting in arrhythmias. In the present study, we investigated the electrical changes and redox abnormalities caused by 72 h hyperoxia treatment in mice. Cardiac repolarization changes were assessed by acquiring electrocardiogram (ECG) and cardiac action potentials (AP). Biochemical assays were employed to identify the pyridine nucleotide changes, Kv1.5 expression and myocardial injury. Hyperoxia treatment caused marked bradycardia, arrhythmia and significantly prolonged (ms) the, RR (186.2 ± 10.7 vs. 146.4 ± 6.2), PR (46.8 ± 3.1 vs. 39.3 ± 1.6), QRS (10.8 ± 0.6 vs. 8.5 ± 0.2), QTc (57.1 ± 3.5 vs. 40 ± 1.4) and JT (13.4 ± 2.1 vs. 7.0 ± 0.5) intervals, when compared with normoxia group. Hyperoxia treatment also induced significant increase in cardiac action potential duration (APD) (ex-APD{sub 90}; 73.8 ± 9.5 vs. 50.9 ± 3.1 ms) and elevated levels of serum markers of myocardial injury; cardiac troponin I (TnI) and lactate dehydrogenase (LDH). Hyperoxia exposure altered cardiac levels of mRNA/protein expression of; Kv1.5, Kvβ subunits and SiRT1, and increased ratios of reduced pyridine nucleotides (NADH/NAD and NADPH/NADP). Inhibition of SiRT1 in H9C2 cells using Splitomicin resulted in decreased SiRT1 and Kv1.5 expression, suggesting that SiRT1 may mediate Kv1.5 downregulation. In conclusion, the cardiotoxic effects of hyperoxia exposure involve ion channel disturbances and redox changes resulting in arrhythmias. - Highlights: • Hyperoxia treatment leads to arrhythmia with prolonged QTc and action potential duration. • Hyperoxia treatment alters cardiac pyridine nucleotide [NAD(P)H/NAD(P)] levels. • SiRT1 and Kv1.5 are co

  16. A CASE REPORT OF AMIODARONE INDUCED MYOPATHY IN A PATIENT OF VENTRICULAR ARRHYTHMIA

    Directory of Open Access Journals (Sweden)

    Rajat

    2014-09-01

    Full Text Available Myopathies are disorders with structural changes or functional impairment of muscle. Voluntary muscle is subject to a range of hereditary and acquired disorders affecting either its structure, or the biochemical processes which convert the chemical energy derived from cell metabolism into mechanical energy in a controlled manner. These disorders present in a limited number of ways, most commonly a symmetrical weakness of the large, power-generating proximal muscles. Drug induced myopathy comes under acquired causes of myopathy. Here we shall be presenting a case of Amiodarone induced myopathy in a 40 years old male patient of ventricular arrhythmia. We shall also discuss the further management of this presentation.

  17. Home monitoring system improves the detection of ventricular arrhythmia and inappropriate shock

    Institute of Scientific and Technical Information of China (English)

    WANG Huan; HUA Wei; DING Li-gang; WANG Jing; CHEN Ke-ping; ZHANG Shu

    2012-01-01

    Background The impact of home monitoring system in the early detection of ventricular arrhythmia and inappropriate shock in daily work is not clear.The aim of this study was to investigate the impact of home monitoring system on the early detection of ventricular arrhythmia and inappropriate shock in daily clinical practice.Methods Cases of implantable cardioverter defibrillator (ICD) implantation with or without the home monitoring system from June 2010 to October 2011 at our center were reviewed.Follow-up was scheduled after implantation.Data relating to the home monitoring ICD were retrieved using a remote transmitter system.Data relating to the other devices were obtained during scheduled follow-up or unscheduled visits.Results Our study involved 69 patients (mean age (68.4±17.6) years,64.3% males,26 in the home monitoring group vs.43 in the non-home monitoring group).In all,561 ventricular arrhythmia episodes were detected in 17 patients (39.5%) in the non-home monitoring group:495 episodes were ventricular tachycardia and 66 episodes were ventricular fibrillation; among these,476 episodes of ventricular tachycardia and 45 episodes of ventricular fibrillation were appropriately diagnosed (96.1% and 68.2%,respectively).In the home monitoring group,389 ventricular arrhythmia episodes were transmitted by the home monitoring system in nine patients (34.6%):348 ventricular tachycardia episodes and 41 ventricular fibrillation episodes.Device detection was appropriate in 348 ventricular tachycardia episodes (100.0%) and 36 ventricular fibrillation episodes (87.8%).The home monitoring group showed a higher appropriate detection rate of ventricular tachycardia (P <0.01) and ventricular fibrillation (P=0.02).The proportion of inappropriate shock was comparable in the two groups (6/11 in the non-home monitoring group vs.1/7 in the home monitoring group; P=O.08).Conclusions The home monitoring ICD was able to provide information relating to inappropriate

  18. Dual-Chamber Pacing for Cardiac Arrhythmias: Controversies in Cloning the Conduction System

    OpenAIRE

    Parsonnet, Victor; Bernstein, Alan D.; Norman, John C.

    1984-01-01

    From the outset, the art and science of cardiac pacing has been beset with a variety of problems. With the passage of time and concentrated effort in the interrelated sciences, many have been solved. We no longer are concerned with premature battery failure or leaking pulse-generator capsules, but now focus on an entirely new set of issues that beg for resolution. Foremost among these is the true role of dual-chamber pacing in the treatment of slow and fast cardiac arrhythmias of a multitude ...

  19. Particulate air pollution induces arrhythmia via oxidative stress and calcium calmodulin kinase II activation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin-Bae [The Division of Cardiology, Kyung Hee University College of Medicine, 1 Hoegi-dong, Dongdaemun-Gu, Seoul (Korea, Republic of); Kim, Changsoo [The Department of Preventive Medicine, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of); Choi, Eunmi [Cardiovascular Research Institute and Severance Biomedical Science Institute, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of); Park, Sanghoon; Park, Hyelim; Pak, Hui-Nam; Lee, Moon-Hyoung [The Division of Cardiology, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of); Shin, Dong Chun [The Department of Preventive Medicine, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of); Hwang, Ki-Chul [Cardiovascular Research Institute and Severance Biomedical Science Institute, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of); The Division of Cardiology, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of); Joung, Boyoung, E-mail: cby6908@yuhs.ac [The Division of Cardiology, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul (Korea, Republic of)

    2012-02-15

    Ambient particulate matter (PM) can increase the incidence of arrhythmia. However, the arrhythmogenic mechanism of PM is poorly understood. This study investigated the arrhythmogenic mechanism of PM. In Sprague–Dawley rats, QT interval was increased from 115.0 ± 14.0 to 142.1 ± 18.4 ms (p = 0.02) after endotracheal exposure of DEP (200 μg/ml for 30 min, n = 5). Ventricular premature contractions were more frequently observed after DEP exposure (100%) than baseline (20%, p = 0.04). These effects were prevented by pretreatment of N-acetylcysteine (NAC, 5 mmol/L, n = 3). In 12 Langendorff-perfused rat hearts, DEP infusion of 12.5 μg/ml for 20 min prolonged action potential duration (APD) at only left ventricular base increasing apicobasal repolarization gradients. Spontaneous early afterdepolarization (EAD) and ventricular tachycardia (VT) were observed in 8 (67%) and 6 (50%) hearts, respectively, versus no spontaneous triggered activity or VT in any hearts before DEP infusion. DEP-induced APD prolongation, EAD and VT were successfully prevented with NAC (5 mmol/L, n = 5), nifedipine (10 μmol/L, n = 5), and active Ca{sup 2+}/calmodulin-dependent protein kinase II (CaMKII) blockade, KN 93 (1 μmol/L, n = 5), but not by thapsigargin (200 nmol/L) plus ryanodine (10 μmol/L, n = 5) and inactive CaMKII blockade, KN 92 (1 μmol/L, n = 5). In neonatal rat cardiomyocytes, DEP provoked ROS generation in dose dependant manner. DEP (12.5 μg/ml) induced apoptosis, and this effect was prevented by NAC and KN 93. Thus, this study shows that in vivo and vitro exposure of PM induced APD prolongation, EAD and ventricular arrhythmia. These effects might be caused by oxidative stress and CaMKII activation. -- Highlights: ► The ambient PM consistently prolonged repolarization. ► The ambient PM induced triggered activity and ventricular arrhythmia. ► These effects were prevented by antioxidants, I{sub CaL} blockade and CaMKII blockade. ► The ambient PM can induce

  20. Effectiveness of morphological and spectral heartbeat characterization on arrhythmia clustering for Holter recordings

    Science.gov (United States)

    Castro-Hoyos, Cristian; Peluffo-Ordóñez, Diego Hernán.; Rodríguez-Sotelo, Jose Luis; Castellanos-Domínguez, Germán.

    2015-01-01

    Heartbeat characterization is an important issue in cardiac assistance diagnosis systems. In particular, wide sets of features are commonly used in long term electrocardiographic signals. Then, if such a feature space does not represent properly the arrhythmias to be grouped, classification or clustering process may fail. In this work a suitable feature set for different heartbeat types is studied, involving morphology, representation and time-frequency features. To determine what kind of features generate better clusters, feature selection procedure is used and assessed by means clustering validity measures. Then the feature subset is shown to produce fine clustering that yields into high sensitivity and specificity values for a broad range of heartbeat types.

  1. QT dispersion and ventricular arrhythmias in children with primary mitral valve prolapse

    Science.gov (United States)

    İmamoğlu, Ebru Yalın; Eroğlu, Ayşe Güler

    2016-01-01

    Aim: To investigate ventricular arrhythmias in children with primary mitral valve prolapse and to evaluate its relation with QT length, QT dispersion, autonomic function tests and heart rate variability measurements. Material and Methods: Fourty two children with mitral valve prolapse and 32 healthy children were enrolled into the study. Twelve-lead electrocardiograms, autonomic function tests, echocardiography and 24-hour rhythm Holter tests were performed. Electrocardiograms were magnified digitally. The QT length was corrected according to heart rate. The patients were grouped according to the number of premature ventricular contractions and presence of complex ventricular arhythmia in the 24-hour rhythm Holter monitor test. Heart rate variability measurements were calculated automatically from the 24-hour rhythm Holter monitor test. Orthostatic hypotension and resting heart rate were used as autonomic function tests. Results: The mean age was 13.9±3.3 years in the patient group and 14.6±3.1 years in the control group (p>0.05). Thirty four of the patients (81%) were female and eight (19%) were male. Twenty five of the control subjects (78%) were female and seven (22%) were male. The QT dispersion and heart rate corrected QT interval were found to be significantly increased in the children with primary mitral valve prolapse when compared with the control group (56±16 ms vs. 43±11 ms, p=0.001; 426±25 ms vs. 407±26 ms, p=0.002, respectively). In 24-hour rhythm Holter monitor tests, ventricular arrhythmias were found in 21 out of 42 patients (50%) and 6 out of 32 control subjects (18.8%) (p=0.006). QT dispersion was found to be significantly increased in patients with premature ventricular contractions ≥ 10/day and/or complex ventricular arrhythmias compared to the control group without ventricular premature beats (p=0.002). There was no significant difference in autonomic function tests and heart rate variability measurements between the patient and control

  2. Fibroblast growth factor homologous factors in the heart: a potential locus for cardiac arrhythmias.

    Science.gov (United States)

    Wei, Eric Q; Barnett, Adam S; Pitt, Geoffrey S; Hennessey, Jessica A

    2011-10-01

    The four fibroblast growth factor homologous factors (FHFs; FGF11-FGF14) are intracellular proteins that bind and modulate voltage-gated sodium channels (VGSCs). Although FHFs have been well studied in neurons and implicated in neurologic disease, their role in cardiomyocytes was unclear until recently. This review discusses the expression profile and function of FHFs in mouse and rat ventricular cardiomyocytes. Recent data show that FGF13 is the predominant FHF in the murine heart, directly binds the cardiac VGSC α subunit, and is essential for normal cardiac conduction. FHF loss-of-function mutations may be unrecognized causes of cardiac arrhythmias, such as long QT and Brugada syndromes.

  3. Risk factors for the occurrence of cardiac arrhythmias in patients on continuous ambulatory peritoneal dialysis.

    Science.gov (United States)

    Canziani, M E; Saragoça, M A; Draibe, S A; Barbieri, A; Ajzen, H

    1993-01-01

    In order to evaluate the risk factors for the occurrence of ventricular arrhythmias (VA) in continuous ambulatory peritoneal dialysis (CAPD), we studied 47 patients by echocardiography, dipyridamole-thallium tests, and biochemical profile. We observed that the group with VA had a greater cardiac mass index dependent only on an increased left ventricular internal diameter. Septum and posterior wall thickness, as well as biochemical variables, were not associated with the presence of VA in CAPD patients. In addition, altered myocardial perfusion was not associated with VA in these patients. PMID:8399625

  4. Classification of Arrhythmias with LDA and ANN using Orthogonal Rotations for Feature Reduction

    Directory of Open Access Journals (Sweden)

    Manpreet Kaur

    2012-07-01

    Full Text Available This paper presents a new approach for feature reduction by using orthogonal rotations. Wavelet coefficients for beat segments are taken as features which are reduced by factor analysis method using orthogonal rotations. LDA (Linear Discriminant Analysis and ANN (Artificial Neural Network classifiers are used for classification. The signals are taken from MIT-BIH arrhythmia database to classify into Normal, PVC, Paced, LBBB and RBBB. The performance of classification output has been compared by the performance parameters. Both the classifiers have given best overall accuracy for equimax rotation. 96% accuracy is achieved with LDA classifier,99.2% accuracy is achieved using ANN.

  5. Role of Genetic Testing in Patients with Ventricular Arrhythmias in Apparently Normal Hearts.

    Science.gov (United States)

    Hofman, Nynke; Wilde, Arthur A M

    2016-09-01

    Ventricular arrhythmias without structural heart disease are responsible for ∼35% of patients who have sudden cardiac death before the age of 40 years. Molecular autopsy and/or cardiological investigation of nearby family members often reveals the diagnosis and genetic testing can be helpful in family screening and risk stratification in disease carriers. Extended gene panels can be screened in a short period of time at low cost. A multidisciplinary team of (genetically) specialized clinicians is necessary to judge all the available details and to decide on the significance of the variant and further strategies. PMID:27521086

  6. Cardiac arrhythmia

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008032 Efficacy of integrated three-dimensional electroanatomic mapping with preacquired magnetic resonance images guide catheter atrial fibrillation ablation. YU Ronghui(喻荣辉), et al. Dept Cardiol, Beijing Anzhen Hosp, Capital Med Univ, Beijing 100029. Chin J Cardiol 2007;35(11):1029-1033. Objective To investigate the efficacy of integrated electroanatomic mapping with preacquired magnetic resonance (MR) images guided catheter at

  7. About Arrhythmia

    Science.gov (United States)

    ... heart doesn't beat properly, it can't pump blood effectively. When the heart doesn't pump blood effectively, the lungs, brain and all other organs ... pump a little larger than a fist. It pumps blood continuously through the circulatory system. Each day the ...

  8. Candiac arrhythmias

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930062 Pathological changes of catheter abla-tion of atrioventricular junction.LI Yue(李越),et al.Dept Cardiol,43rd Hosp,Kunming.Chin Cir J 1992;7(4):350-351.Pathological examinations were carried out in34 mongrel dogs following catheter ablation ofthe AV junction,gross pathological examination

  9. Cardiac arrhythmias

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    970281 Clinical efficacy and safety of intravenous es-molol in the treatment of supraventricular tachyarrth-mias: multiple centers analysis of 309 cases. YOU Kai(游凯), et a1. PUMC Hosp, Beijing, 100730. Chin JCardiol 1996; 24(6): 404-407。

  10. Cardiac arrhythmias

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008272 Prospective study on the prognosis in patients with ventricular tachycardia or fibrillation treated with implantable automatic cardiovertor defibrillator. LIU Zhongmei(刘中梅), et al. Dept Cardiol, 1st Affili Hosp, Kunming Med Coll, Kunming 650032. Chin J Cardiol 2008;36(4):309-312.Objective To explore the effect of implantable automatic cardiovertor defibrillator(ICD)on improvement of the prognosis of patients with ventricular tachycardia or fibrillation(VT/VF).To compare the advantages and

  11. Mechanisms and Clinical Management of Ventricular Arrhythmias following Blunt Chest Trauma

    Directory of Open Access Journals (Sweden)

    Daniel H. Wolbrom

    2016-01-01

    Full Text Available Nonpenetrating, blunt chest trauma is a serious medical condition with varied clinical presentations and implications. This can be the result of a dense projectile during competitive and recreational sports but may also include other etiologies such as motor vehicle accidents or traumatic falls. In this setting, the manifestation of ventricular arrhythmias has been observed both acutely and chronically. This is based on two entirely separate mechanisms and etiologies requiring different treatments. Ventricular fibrillation can occur immediately after chest wall injury (commotio cordis and requires rapid defibrillation. Monomorphic ventricular tachycardia can develop in the chronic stage due to underlying structural heart disease long after blunt chest injury. The associated arrhythmogenic tissue may be complex and provides the necessary substrate to form a reentrant VT circuit. Ventricular tachycardia in the absence of overt structural heart disease appears to be focal in nature with rapid termination during ablation. Regardless of the VT mechanism, patients with recurrent episodes, despite antiarrhythmic medication in the chronic stage following blunt chest injury, are likely to require ablation to achieve VT control. This review article will describe the mechanisms, pathophysiology, and treatment of ventricular arrhythmias that occur in both the acute and chronic stages following blunt chest trauma.

  12. Determination of the vectorelectrogram in isolated rat atria: application to the study of arrhythmias

    International Nuclear Information System (INIS)

    Atrial tachyarrhythmias, the most frequent type of cardiac arrhythmia, are associated with increased stroke risk. Reentry and focal activity are considered as the main mechanisms underlying this dysfunction. In this study, we describe determination of the vectorelectrogram in isolated rat atria as a means to distinguish different patterns of electrical propagation. In all studied right atria beating at sinus rhythm, the mean electric vector (MEV) trajectory was clockwise, and each cycle was preceded by electric diastole (null MEV), either in the absence or presence of muscarinic cholinergic or β-adrenergic receptor stimulation. During cholinergic tachyarrhythmia (induced by high-rate electric stimulation in both atria, plus exposure to carbachol in left atria), vector loops were ellipsoidal and stable, with variable direction, and did not cross the origin, which is consistent with reentrant activation and with findings obtained in vivo by other authors. In contrast, during spontaneous activity induced by rapid pacing in isoproterenol-exposed left atria, vector loops were similar to those in right atria at sinus rhythm, thus suggestive of focal activity. It is concluded that the vectorelectrogram approach allows discrimination of different patterns of propagation during arrhythmia in isolated atria and may be useful for high-output tests of pro- and anti-arrhythmic compounds

  13. Rapidly detecting disorder in rhythmic biological signals: a spectral entropy measure to identify cardiac arrhythmias

    CERN Document Server

    Staniczenko, Phillip P A; Jones, Nick S

    2008-01-01

    We consider the use of a running measure of power spectrum disorder to distinguish between the normal sinus rhythm of the heart and two forms of cardiac arrhythmia: atrial fibrillation and atrial flutter. This is motivated by characteristic differences in the spectra of beats during the three rhythms. We plot patient data derived from 10-beat windows on a `disorder map' and identify rhythm-defining ranges in the level and variance of spectral entropy values. Employing the spectral entropy within an automatic arrhythmia detection algorithm enables the classification of periods of atrial fibrillation from the time series of patients' beats. When the algorithm is set to identify abnormal rhythms within 6s it agrees with 85.7% of the annotations of professional rhythm assessors; for a response time of 30s this becomes 89.5%, and with 60s it is 90.3%. The algorithm provides a rapid way to detect atrial fibrillation, demonstrating usable response times as low as six seconds. Measures of disorder in the frequency do...

  14. Cell and gene therapy for arrhythmias: Repair of cardiac conduction damage

    Institute of Scientific and Technical Information of China (English)

    Yong-Fu Xiao

    2011-01-01

    Action potentials generated in the sinoatrial node(SAN)dominate the rhythm and rate of a healthy human heart.Subsequently,these action potentials propagate to the whole heart via its conduction system .Abnormalities of impulse generation and/or propagation in a heart can cause arrhythmias.For example,SAN dysfunction or conduction block of the atrioventricular node can lead to serious bradycardia which is currently treated with an implanted electronic pacemaker.On the other hand conduction damage may cause reentrant tachyarrhythmias which are primarily treated pharmacologically or by medical device-based therapies,including defibrillation and tissue ablation.However,drug therapies sometimes may not be effective or are associated with serious side effects.Device-based therapies for cardiac arrhythmias,even with well developed technology,still face inadequacies,limitations,hardware complications,and other challenges.Therefore,scientists are actively seeking other alternatives for antiarrhythmic therapy.In particular,cells and genes used for repairing cardiac conduction damage/defect have been investigated in various studies both in vitro and in vivo.Despite the complexities of the excitation and conduction systems of the heart,cell and gene-based strategies provide novel alternatives for treatment or cure of cardiac anhythmias.This review summarizes some highlights of recent research progress in this field.

  15. Low dialysate potassium concentration: an overrated risk factor for cardiac arrhythmia?

    Science.gov (United States)

    Abuelo, J Gary

    2015-01-01

    Serum potassium concentrations rise with dietary potassium intake between dialysis sessions and are often at hyperkalemic levels by the next session. Conversely, potassium concentrations fall during each hemodialysis, and sometimes reach hypokalemic levels by the end. Low potassium dialysate, which rapidly decreases serum potassium and often brings it to hypokalemic levels, is almost universally considered a risk factor for life-threatening arrhythmias. While there is little doubt about the threat of lethal arrhythmias due to hyperkalemia, convincing evidence for the danger of low potassium dialysate and rapid or excess potassium removal has not been forthcoming. The original report of more frequent ventricular ectopy in early dialysis that was improved by reducing potassium removal has received very little confirmation from subsequent studies. Furthermore, the occurrence of ventricular ectopy during dialysis does not appear to predict mortality. Studies relating sudden deaths to low potassium dialysate are countered by studies with more thorough adjustment for markers of poor health. Dialysate potassium concentrations affect the excursions of serum potassium levels above or below the normal range, and have the potential to influence dialysis safety. Controlled studies of different dialysate potassium concentration and their effect on mortality and cardiac arrests have not been done. Until these results become available, I propose interim guidelines for the setting of dialysate potassium levels that may better balance risks and benefits.

  16. [Value of intravenous flecainide in electro-induced supraventricular arrhythmia. Apropos of 37 cases].

    Science.gov (United States)

    Graux, P; Mekerke, W; Lemaire, N; Jacquemart, T; Durieu-Ghis, C; Rihani, R; Cornaert, P; Dutoit, A; Croccel, L

    1992-01-01

    Thirty-seven patients presenting with electro-induced supraventricular arrhythmia sustained for more than 10 min or symptomatic received an intravenous injection of flecainide acetate (1.5 mg/kg; 10 mg/min). There were 24 cases of atrial fibrillation, 13 of atrial tachysystole with more than 180 beats per minute. Electrophysiological exploration was carried out for syncope (13 cases), lipothymia with palpitations (11 cases) or without palpitations (8 cases), or for a stroke of unknown origin. The induced arrhythmia was the only electrophysiological abnormality in 57% of cases. A return of sinus rhythm was obtained in 70% of cases during the injection (12 cases) or shortly after the end of the injection (14 patients). Safety was good, with the exception of the onset of two junctional rhythms and one case of non-syncopal monomorphic ventricular tachycardia. After an initial reduction, the PR, QRS, PA and HV intervals were significantly longer than baseline, whereas the AH space and the systolic blood pressure remained virtually unchanged. Thus the provision of IV flecainide acetate can only be beneficial in carrying out study protocols of abnormalities of the atrial substrate. PMID:1558365

  17. The relationship between ECG signs of atrial infarction and the development of supraventricular arrhythmias in patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Nielsen, F E; Andersen, H H; Gram-Hansen, P;

    1992-01-01

    ECGs obtained on arrival at the hospital from 277 patients with acute myocardial infarction were analyzed retrospectively for PR displacements, which were classified as major or minor criteria for atrial infarction and related to the later occurrence of supraventricular arrhythmia in the hospital...... arrhythmias, giving odds ratios of 9.9 and 3.7, respectively. Enzyme-estimated infarct size, the occurrence of heart failure, and mortality rates did not differ in patients with or without major criteria for atrial infarction. We conclude that the occurrence of PR segment displacements on the admission ECG...

  18. Ambulatory cardiac arrhythmias in relation to mild hypokalaemia and prognosis in community dwelling middle-aged and elderly subjects

    DEFF Research Database (Denmark)

    Mattsson, Nick; Sadjadieh, Golnaz; Kumarathurai, Preman;

    2016-01-01

    with frequency of premature ventricular complexes (PVCs) especially in combination with diuretic treatment (r = -0.22, P = 0.015). Hypokalaemia was not associated with supraventricular arrhythmias. Subjects at lowest quintile of p-potassium (mean 3.42, range 2.7-3.6 mmol/L) were defined as hypokalaemic......: In middle-aged and elderly subjects with no manifest heart disease, mild hypokalaemia is associated with increased rate of ventricular but not supraventricular arrhythmias. Hypokalaemia interacts synergistically with increased ventricular ectopy to increase the risk of adverse events....

  19. Manual treating of 2 cases with cervicogenous arrhythmia%手法治疗颈源性心律失常2例

    Institute of Scientific and Technical Information of China (English)

    林绵辉; 陈镇荣

    2003-01-01

    @@ MATERIALS AND METHODS Materials 2 cases were diagnosed as arrhythmia without clear reasons by ECG and were confirmed that they didn't suffered organic diseases.All the cases received anti- arrhythmia and heart muscle nutrition drugs and didn't gain good effects.

  20. SpiNon- Invasive Diagnostics and Results of Interventive Treatment of Cardiac Arrhythmia Using the New System of Non-Invasive Surface Mapping “Amycard 01K”

    Directory of Open Access Journals (Sweden)

    Revishvili A. Sh.

    2012-09-01

    Conclusion. Using results of the surface activation mapping in patients with various cardiac arrhythmias shows its high diagnostic value and the necessity for a preoperative examination. Previously held topical diagnosis of arrhythmogenic substrate will reduce the time of the arrhythmia origin finding, to avoid possible adverse intraoperative complications such as a damage of coronary vessels, as well as reduce the time of intraoperative fluoroscopy.

  1. Experience of treatment of heart rhabdomyomas in combination with various arrhythmias and conduction disorders

    Directory of Open Access Journals (Sweden)

    Bockeria L. A.

    2014-12-01

    Full Text Available Оbjective. Presentation the experience of diagnosis and treatment of heart rhabdomyomas in combination withvarious arrhythmias and conduction disorders.Material and methods. In archival material found 9 records of pediatric patients treated in A.N. BakoulevCenter for Cardiovascular Surgery from June 2004 to September 2013 with cardiac rhabdomyomas. The ageofpatients ranged from 19 days to 17 years. Along with the general clinical studies patients perfomed electro-cardiography (ECG, Holter ECG, echocardiography with doppler, computed tomography (CT and cardiacmagnetic resonance imaging (MRI with contrast. Rhabdomyomas localized in the left ventricle with3patients, in the right ventricle with 3 patients, in the right atrium – 2 patients and in the left atrium –1patient. Intramural and mixed rhabdomyomas growth was accompanied by a variety of arrhythmias andconduction of the heart, which were observed in 6 patients. Among them one cases were registered: manifesting Wolff–Parkinson–White syndrome, continuous recurrent atrial tachycardia, atrial fibrillation/flutter,full blockade of the right bundle branch, atrioventricular (AV block 3rd degree, a weakness syndrome sinusnode and paroxysmal atrial tachycardia.Results. Surgical care was performed in 5 cases. In 4 cases the tumor was unresectable or surgical treatment has not been shown. These patients were released under the supervision of a cardiologist at the place of residence on drug therapy. The most frequent localization rhabdomyomas of the heart – the ventricles(66.7%. Rhabdomyomas of the heart in combination with disorders of rhythm and conduction was observedin 6 patient (66.7%. Surgery included resection of rhabdomyomas of the heart under conditions of artificialblood circulation and pharmacological cardioplegia. Patient with atrial fibrillation/flutter in 1 cases was performed radiofrequency modification operation Cox Maze. In this group of patients in-hospital mortality is 0

  2. Scintigraphic assessment of cardiac sympathetic innervation with I-123-metaiodobenzylguanidine in cardiomyopathy. Special reference to cardiac arrhythmia

    Energy Technology Data Exchange (ETDEWEB)

    Asano, Takahisa; Otsuka, Nobuaki; Sone, Teruki; Mimura, Hiroaki; Yanagimoto, Shinichi; Tomomitsu, Tatsushi; Fukunaga, Masao [Kawasaki Medical School, Kurashiki, Okayama (Japan); Morita, Koichi

    1999-07-01

    Cardiac sympathetic imagings with I-123-metaiodobenzylguanidine (MIBG) were carried out in 5 cases with dilated cardiomyopathy (DCM), 26 cases with hypertrophic cardiomyopathy (HCM), and 4 cases without cardiac disease as a control to assess cardiac sympathetic innervation qualitatively and quantitatively, and to clarify the relation of MIBG accumulation to arrhythmia. MIBG scintigraphy was performed at 15 min. (early image) and 4 hr. (delayed image) after intravenous injection of MIBG 111 MBq. The MIBG uptake ratio of mediastinum (H/M) and the cardiac washout rate (WR) from early to delayed images were calculated. On both early and delayed SPECTs, MIBG uptake was assessed by defect scores (DSs). Regarding the cases with HCM, the MIBG uptake ratio, WR, and DS were also compared in cases with and without arrhythmia. In DCM, the MIBG uptake on delayed SPECT was markedly low, the H/M ratio was significantly lower, and the DS was significantly higher than in the control (all p<0.05). As for the WR, there was no significant difference between HCM, DCM and the control. In HCM, significantly reduced MIBG uptake was observed in cases with ventricular techycardia (VT) and in cases with atrial fibrillation (Af), as compared with cases without arrhythmia (all p<0.05). There results suggest that MIBG scintigraphy might be a useful tool in the assessment of cardiac sympathetic abnormalities in cardiomyopathy, especially in cases with arrhythmia. (author)

  3. Risk Factors for Malignant Ventricular Arrhythmias in Lamin A/C Mutation Carriers A European Cohort Study

    NARCIS (Netherlands)

    van Rijsingen, Ingrid A. W.; Arbustini, Eloisa; Elliott, Perry M.; Mogensen, Jens; Hermans-van Ast, Johanna F.; van der Kooi, Anneke J.; van Tintelen, J. Peter; van den Berg, Maarten P.; Pilotto, Andrea; Pasotti, Michele; Jenkins, Sharon; Rowland, Camilla; Aslam, Uzma; Wilde, Arthur A. M.; Perrot, Andreas; Pankuweit, Sabine; Zwinderman, Aeilko H.; Charron, Philippe; Pinto, Yigal M.

    2012-01-01

    Objectives The purpose of this study was to determine risk factors that predict malignant ventricular arrhythmias (MVA) in Lamin A/C (LMNA) mutation carriers. Background LMNA mutations cause a variety of clinical phenotypes, including dilated cardiomyopathy and conduction disease. Many LMNA mutation

  4. Coxsackie and adenovirus receptor is a modifier of cardiac conduction and arrhythmia vulnerability in the setting of myocardial ischemia.

    NARCIS (Netherlands)

    Marsman, R.F.; Bezzina, C.R.; Freiberg, F.; Verkerk, A.O.; Adriaens, M.E.; Podliesna, S.; Chen, C.; Purfurst, B.; Spallek, B.; Koopmann, T.T.; Baczko, I.; Remedios, C.G. Dos; George AL, J.r.; Bishopric, N.H.; Lodder, E.M.; Bakker, J.M. de; Fischer, R.; Coronel, R.; Wilde, A.A.; Gotthardt, M.; Remme, C.A.

    2014-01-01

    OBJECTIVES: The aim of this study was to investigate the modulatory effect of the coxsackie and adenovirus receptor (CAR) on ventricular conduction and arrhythmia vulnerability in the setting of myocardial ischemia. BACKGROUND: A heritable component in the risk of ventricular fibrillation during myo

  5. Differential Susceptibility and the Early Development of Aggression: Interactive Effects of Respiratory Sinus Arrhythmia and Environmental Quality

    Science.gov (United States)

    Eisenberg, Nancy; Sulik, Michael J.; Spinrad, Tracy L.; Edwards, Alison; Eggum, Natalie D.; Liew, Jeffrey; Sallquist, Julie; Popp, Tierney K.; Smith, Cynthia L.; Hart, Daniel

    2012-01-01

    The purpose of the current study was to predict the development of aggressive behavior from young children's respiratory sinus arrhythmia (RSA) and environmental quality. In a longitudinal sample of 213 children, baseline RSA, RSA suppression in response to a film of crying babies, and a composite measure of environmental quality (incorporating…

  6. Trajectories of Children's Internalizing Symptoms: The Role of Maternal Internalizing Symptoms, Respiratory Sinus Arrhythmia and Child Sex

    Science.gov (United States)

    Wetter, Emily K.; El-Sheikh, Mona

    2012-01-01

    Background: We assessed trajectories of children's internalizing symptoms as predicted by interactions among maternal internalizing symptoms, respiratory sinus arrhythmia (RSA) and child sex. Method: An ethnically and socioeconomically diverse sample of children (n = 251) participated during three study waves. Children's mean ages were 8.23 years…

  7. Beneficial effects of l-leucine and l-valine on arrhythmias, hemodynamics and myocardial morphology in rats.

    Science.gov (United States)

    Mitręga, Katarzyna; Zorniak, Michał; Varghese, Benoy; Lange, Dariusz; Nożynski, Jerzy; Porc, Maurycy; Białka, Szymon; Krzemiński, Tadeusz F

    2011-09-01

    Branched chain amino acids (BCAA) have been shown to have a general protective effect on the heart in different animal models as well as in humans. However, so far no attempt has been made to specifically elucidate their influence on arrhythmias. Our study was performed to evaluate whether an infusion of either l-leucine or l-valine in a dose of 1mgkg(-1)h(-1) 10min before a 7-min period of left anterior descending artery occlusion followed by 15min of reperfusion, had an effect on arrhythmias measured during the reperfusion phase in the ischemia- and reperfusion-induced arrhythmias model in rats in vivo. The effect of the infusion of these substances on mean arterial blood pressure was monitored throughout the experiment. Both of the tested amino acids exhibited significant antiarrhythmic properties. l-Leucine reduced the duration of ventricular fibrillation (Pvaline decreased the duration of ventricular fibrillation (PValine lowered blood pressure in all phases of the experiment (Pvaline in the dose that was used attenuates arrhythmias and are hypotensive in their influence. Our findings lend support to the many ongoing investigations into the benefit of the application of l-leucine and l-valine in cardiology like their addition to cardioplegic solutions.

  8. Use of sympathomimetic drugs leads to increased risk of hospitalization for arrhythmias in patients with congestive heart failure

    DEFF Research Database (Denmark)

    Bouvy, M L; Heerdink, E R; De Bruin, M L;

    2000-01-01

    BACKGROUND: Sympathomimetic agents have a direct positive chronotropic effect on heart rate and may cause hypokalemia, even when administered by inhalation. In selected patients (e.g., patients with congestive heart failure [CHF]) this can lead to arrhythmias. Despite the potential adverse effects...

  9. Noninvasive low-frequency electromagnetic stimulation of the left stellate ganglion reduces myocardial infarction-induced ventricular arrhythmia

    Science.gov (United States)

    Wang, Songyun; Zhou, Xiaoya; Huang, Bing; Wang, Zhuo; Zhou, Liping; Wang, Menglong; Yu, Lilei; Jiang, Hong

    2016-01-01

    Noninvasive magnetic stimulation has been widely used in autonomic disorders in the past few decades, but few studies has been done in cardiac diseases. Recently, studies showed that low-frequency electromagnetic field (LF-EMF) might suppress atrial fibrillation by mediating the cardiac autonomic nervous system. In the present study, the effect of LF-EMF stimulation of left stellate ganglion (LSG) on LSG neural activity and ventricular arrhythmia has been studied in an acute myocardium infarction canine model. It is shown that LF-EMF stimulation leads to a reduction both in the neural activity of LSG and in the incidence of ventricular arrhythmia. The obtained results suggested that inhibition of the LSG neural activity might be the causal of the reduction of ventricular arrhythmia since previous studies have shown that LSG hyperactivity may facilitate the incidence of ventricular arrhythmia. LF-EMF stimulation might be a novel noninvasive substitute for the existing implant device-based electrical stimulation or sympathectomy in the treatment of cardiac disorders. PMID:27470078

  10. The mechanism of KV4.3 voltage-gated potassium channel in arrhythmia induced by sleep deprivation in rat

    Directory of Open Access Journals (Sweden)

    Ya-jing ZHANG

    2011-03-01

    Full Text Available Objective To investigate the effect of sleep deprivation(SD on the changes in electrocardiogram and mRNA and protein expression of KV4.3 voltage-gated potassium channel in rats,and explore the related mechanisms of arrhythmia induced by SD.Methods A total of 48 adult male SD rats were randomly divided into 6 groups(8 each: normal control(CC group,tank control(TC group,1-,3-,5-and 7-day SD group.Animal model of SD was established by modified multiple platform method,and electrocardiogram was recorded on 1st,3rd,5th,and 7th of experiment.Protein and mRNA expressions of KV4.3 voltage-gated potassium channel were measured by real-time PCR and Western blotting analysis.Results The main changes on electrocardiogram following SD were arrhythmia.Compared with the CC group,rats in TC group showed sinus tachycardia in electrocardiogram: frequent atrial premature beats were observed one day after SD;ventricular arrhythmias,such as frequent polymorphic ventricular premature beats and paroxysmal ventricular tachycardia were observed three days after SD;incomplete right bundle branch block wave occurred five days after SD;the electrocardiogram showed third-degree atrioventricular(AV block wave seven days after SD,which indicated atrial arrhythmia and ventricular arrhythmia respectively.Ventricular escape beat,sinus arrest as well as the fusion of obviously elevated ST segment and T-wave were also observed.The expression levels of KV4.3 voltage-gated potassium channel decreased with prolongation of SD time.The expression of mRNA and protein of KV4.3 potassium channel in 7-day SD rats were only the one ninth and one fourth of levels in CC group.Conclusion Sleep deprivation can cause arrhythmia,and decreased expression of KV4.3 voltage-gated potassium channel may possibly be one of the reasons of arrhythmia induced by SD.

  11. Percutaneous autonomic neural modulation: A novel technique to treat cardiac arrhythmia

    International Nuclear Information System (INIS)

    Ablation and anti-arrhythmic medications have shown promise but have been met with varying success and unwanted side effects such as myocardial injury, arrhythmias, and morbidity from invasive surgical intervention. The answer to improving efficacy of ablation may include modulation of the cardiac aspect of the autonomic nervous system. Our lab has developed a novel approach and device to navigate the oblique sinus and to use DC current and saline/alcohol irrigation to selectively stimulate and block the autonomic ganglia found on the epicardial side of the heart. This novel approach minimizes myocardial damage from thermal injury and provides a less invasive and targeted approach. For feasibility, proof-of-concept, and safety monitoring, we carried out canine studies to test this novel application. Our results suggest a safer and less invasive way of modulating arrhythmogenic substrate that may lead to improved treatment of AF in humans

  12. Percutaneous autonomic neural modulation: A novel technique to treat cardiac arrhythmia

    Energy Technology Data Exchange (ETDEWEB)

    DeSimone, Christopher V.; Madhavan, Malini [Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN (United States); Venkatachalam, Kalpathi L. [Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Jacksonville, FL (United States); Knudson, Mark B. [Mayo Clinic, Rochester, MN (United States); EnteroMedics, EnteroMedics, St. Paul, MN (United States); Asirvatham, Samuel J., E-mail: asirvatham.samuel@mayo.edu [Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN (United States); Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN (United States)

    2013-05-15

    Ablation and anti-arrhythmic medications have shown promise but have been met with varying success and unwanted side effects such as myocardial injury, arrhythmias, and morbidity from invasive surgical intervention. The answer to improving efficacy of ablation may include modulation of the cardiac aspect of the autonomic nervous system. Our lab has developed a novel approach and device to navigate the oblique sinus and to use DC current and saline/alcohol irrigation to selectively stimulate and block the autonomic ganglia found on the epicardial side of the heart. This novel approach minimizes myocardial damage from thermal injury and provides a less invasive and targeted approach. For feasibility, proof-of-concept, and safety monitoring, we carried out canine studies to test this novel application. Our results suggest a safer and less invasive way of modulating arrhythmogenic substrate that may lead to improved treatment of AF in humans.

  13. 3D/2D Registration of Mapping Catheter Images for Arrhythmia Interventional Assistance

    CERN Document Server

    Fallavollita, Pascal

    2009-01-01

    Radiofrequency (RF) catheter ablation has transformed treatment for tachyarrhythmias and has become first-line therapy for some tachycardias. The precise localization of the arrhythmogenic site and the positioning of the RF catheter over that site are problematic: they can impair the efficiency of the procedure and are time consuming (several hours). Electroanatomic mapping technologies are available that enable the display of the cardiac chambers and the relative position of ablation lesions. However, these are expensive and use custom-made catheters. The proposed methodology makes use of standard catheters and inexpensive technology in order to create a 3D volume of the heart chamber affected by the arrhythmia. Further, we propose a novel method that uses a priori 3D information of the mapping catheter in order to estimate the 3D locations of multiple electrodes across single view C-arm images. The monoplane algorithm is tested for feasibility on computer simulations and initial canine data.

  14. 3D/2D Registration of Mapping Catheter Images for Arrhythmia Interventional Assistance

    Directory of Open Access Journals (Sweden)

    Pascal Fallavollita

    2009-09-01

    Full Text Available Radiofrequency (RF catheter ablation has transformed treatment for tachyarrhythmias and has become first-line therapy for some tachycardias. The precise localization of the arrhythmogenic site and the positioning of the RF catheter over that site are problematic: they can impair the efficiency of the procedure and are time consuming (several hours. Electroanatomic mapping technologies are available that enable the display of the cardiac chambers and the relative position of ablation lesions. However, these are expensive and use custom-made catheters. The proposed methodology makes use of standard catheters and inexpensive technology in order to create a 3D volume of the heart chamber affected by the arrhythmia. Further, we propose a novel method that uses a priori 3D information of the mapping catheter in order to estimate the 3D locations of multiple electrodes across single view C-arm images. The monoplane algorithm is tested for feasibility on computer simulations and initial canine data.

  15. Buffering blood pressure fluctuations by respiratory sinus arrhythmia may in fact enhance them: a theoretical analysis

    CERN Document Server

    Buchner, Teodor; Gielerak, Grzegorz

    2010-01-01

    Using a three-compartment model of blood pressure dynamics, we analyze theoretically the short term cardiovascular variability: how the respiratory-related blood pressure fluctuations are buffered by appropriate heart rate changes: i.e. the respiratory sinus arrhythmia. The buffering is shown to be crucially dependent on the time delay between the stimulus (such as e.g. the inspiration onset) and the application of the control (the moment in time when the efferent response is delivered to the heart). This theoretical analysis shows that the buffering mechanism is effective only in the upright position of the body. It explains a paradoxical effect of enhancement of the blood pressure fluctuations by an ineffective control. Such a phenomenon was observed experimentally. Using the basis of the model, we discuss the blood pressure variability and heart rate variability under such clinical conditions as the states of expressed adrenergic drive and the tilt-test during the parasympathetic blockade or fixed rate atr...

  16. THE POSSIBILITIES OF ANTIARRHYTHMIC THERAPY IN PRIMARY PREVENTION OF DEATH IN PATIENTS WITH VENTRICULAR ARRHYTHMIAS

    Directory of Open Access Journals (Sweden)

    Yu. A. Bunin

    2016-01-01

    Full Text Available Highlights of primary prevention of death in patients with ventricular arrhythmias (VA are discussed. Overview of all main clinical trials exploring various anti-arrhythmic drugs in prevention of death in patients with VA is presented. It is emphasized that in patients with organic heart disease and VA only beta-blockers and amiodarone are able to reduce mortality, while other drugs have no effect on mortality, or they even increase mortality mainly due to arrhythmogenic effect. Recent clinical studies of the cardioverter-defibrillators efficacy in these patients are presented. It is shown that the use of cardioverter defibrillators compared with pharmacotherapy is more effective in prevention of fatal outcomes.

  17. Automatic cardiac arrhythmia detection and classification using vectorcardiograms and complex networks.

    Science.gov (United States)

    Queiroz, Vinícius; Luz, Eduardo; Moreira, Gladston; Guarda, Álvaro; Menotti, David

    2015-01-01

    This paper intends to bring new insights in the methods for extracting features for cardiac arrhythmia detection and classification systems. We explore the possibility for utilizing vectorcardiograms (VCG) along with electrocardiograms (ECG) to get relevant informations from the heartbeats on the MIT-BIH database. For this purpose, we apply complex networks to extract features from the VCG. We follow the ANSI/AAMI EC57:1998 standard, for classifying the beats into 5 classes (N, V, S, F and Q), and de Chazal's scheme for dataset division into training and test set, with 22 folds validation setup for each set. We used the Support Vector Machinhe (SVM) classifier and the best result we chose had a global accuracy of 84.1%, while still obtaining relatively high Sensitivities and Positive Predictive Value and low False Positive Rates, when compared to other papers that follows the same evaluation methodology that we do. PMID:26737464

  18. Hepatocyte growth factor gene therapy reduces ventricular arrhythmia in animal models of myocardial ischemia.

    Directory of Open Access Journals (Sweden)

    Yumoto,Akihisa

    2005-06-01

    Full Text Available

    It was recently reported that gene therapy using hepatocyte growth factor (HGF has the potential to preserve cardiac function after myocardial ischemia. We speculated that this HGF gene therapy could also prevent ventricular arrhythmia. To investigate this possibility, we examined the antiarrhythmic effect of HGF gene therapy in rat acute and old myocardial infarction models. Myocardial ischemia was induced by ligation of the left descending coronary artery. Hemagglutinating virus of Japan (HVJ-coated liposome containing HGF genes were injected directly into the myocardium fourteen days before programmed pacing. Ventricular fibrillation (VFwas induced by programmed pacing. The VF duration was reduced and the VF threshold increased after HGF gene therapy ( p< 0.01. Histological analyses revealed that the number of vessels in the ischemic border zone was greatly increased after HGF gene injection. These findings revealed that HGF gene therapy has an anti-arrhythmic effect after myocardial ischemia.

  19. A NOVEL APPROACH TO ARRHYTHMIA CLASSIFICATION USING RR INTERVAL AND TEAGER ENERGY

    Directory of Open Access Journals (Sweden)

    CHANDRAKAR KAMATH

    2012-12-01

    Full Text Available It is hypothesized that a key characteristic of electrocardiogram (ECG signal is its nonlinear dynamic behaviour and that the nonlinear component changes more significantly between normal and arrhythmia conditions than the linear component. The usual statistical descriptors used in RR (R to R interval analysis do not capture the nonlinear disposition of RR interval variability. In this paper we explore a novel approach to extract the features from nonlinear component of the RR interval signal using Teager energy operator (TEO. The key feature of Teager energy is that it models the energy of the source that generated the signal rather than the energy of the signal itself. Hence any deviations in regular rhythmic activity of the heart get reflected in the Teager energy function. The classification evaluated on MIT-BIH database, with RR interval and mean of Teager energy computed over RR interval as features, exhibits an average accuracy that exceeds 99.79%.

  20. Cardiac Resynchronization Therapy Defibrillator Treatment in a Child with Heart Failure and Ventricular Arrhythmia.

    Science.gov (United States)

    Kim, Hak Ju; Cho, Sungkyu; Kim, Woong-Han

    2016-08-01

    Cardiac resynchronization therapy (CRT) is a new treatment for refractory heart failure. However, most patients with heart failure treated with CRT are adults, middle-aged or older with idiopathic or ischemic dilated cardiomyopathy. We treated a 12-year-old boy, who was transferred after cardiac arrest, with dilated cardiomyopathy, left bundle-branch block, and ventricular tachycardia. We performed cardiac resynchronization therapy with a defibrillator (CRT-D). After CRT-D, left ventricular ejection fraction improved from 22% to 44% assessed by echocardiogram 1 year postoperatively. On electrocardiogram, QRS duration was shortened from 206 to 144 ms. The patient's clinical symptoms also improved. For pediatric patients with refractory heart failure and ventricular arrhythmia, CRT-D could be indicated as an effective therapeutic option. PMID:27525239

  1. Effects of Hydroalcoholic Extract of Cynodon Dactylon (L. Pers. on ISchemia/Reperfusion-Induced Arrhythmias

    Directory of Open Access Journals (Sweden)

    A Garjani

    2008-09-01

    Full Text Available Background and purpose of the study: Probable antiarrhythmic effects of Cynodon dactylon (L. pers. (family Poaceae against ischemia/reperfusion (I/R-induced arrhythmias were investigated in isolated rat heart. Methods: The hearts were subjected to 30min regional ischemia followed by 30min reperfusion and perfused with hydroalcoholic extract of rhizome of C. dactylon (25, 50, 100 and 200µg/ml. Results: During ischemia, the extract produced marked reduction in the number, duration and incidences of ventricular tachycardia (VT at 25 and 50µg/ml (p<0.001 and p<0.01, respectively. Total number of ischemic ventricular ectopic beats (VEBs were lowered by 25-100µg/ml (p<0.001, p<0.001 and p<0.05, respectively. At the reperfusion phase, C. dactylon (25 and 50µg/ml decreased incidence of VT from 100% (control to 13 and 33% (p<0.001 and p<0.05 respectively. Duration and number of VT and total VF incidence were also reduced at the same concentration (p<0.05 for all. Perfusion of the extract (25-100µg/ml was markedly lowered reversible VF duration from 218±99sec to 0 sec, 0 sec and 10±5sec (p<0.01, p<0.01 and p<0.05 respectively. Moreover, C. dactylon (25 and 50µg/ml decreased number of total VEBs from 349±73 to 35±17 (p<0.001 and 66±26 (p<0.01. In this study, it was also shown that perfusion of the extract produced a marked and concentration-dependent positive inotropic effect. Conclusion: The findings of this study indicate that C. dactylon produce protective effects against I/R-induced arrhythmias in isolated rat hearts probably by increase in the myocardial contractility and as a result by improvement of hemodynamic factors.

  2. Non cancerous diseases following a chronic intern contamination by caesium 137: cataracts and cardiac arrhythmias

    International Nuclear Information System (INIS)

    This work of thesis joins within the framework of an analysis of the sanitary consequences of the nuclear accident of Chernobylsk. Since 2005, the I.R.S.N. is interested in the not cancerous pathologies (cataracts, and cardiac arrhythmias) observed among the children living on the contaminated territories after the fallout of Chernobylsk and has in this aim implemented a research programme called E.P.I.C.E. (Evaluation of the pathologies induced by a chronicle contamination by cesium) whom objective is to show an eventual link between the chronicle ingestion of contaminated food and these pathologies emergence. An exploitation of the results of the pilot study,first phase of the E.P.I.C.E. program was realized. The analysis was completed by two bibliographical reviews relative to the knowledge available on these diseases. The results of this pilot study suggest: on one hand, an absence of link between the activity in cesium 137 at the level of the heart, of the whole body and the emergence of disorder of the heart rhythm; on the other hand, for the cases of cataract, a link between the load in cesium 137 at the neck level and the emergence of the disease in 40 % of the cases. However, these results must be considered with caution because several limits and, in particular, a way of selection affect this study. concerning the scientific literature, this one stays rather poor because only thee articles make reference to a relationship between cesium 137 and the emergence of these non cancerous pathologies. After having exposed the context, this thesis draws up the situation of knowledge relative to cataracts and to cardiac arrhythmias and their possible relationship with ionizing radiations, collect the results stemming from the analysis of the pilot study and envisages future epidemiological studies. (N.C.)

  3. Reduction of false arrhythmia alarms using signal selection and machine learning.

    Science.gov (United States)

    Eerikäinen, Linda M; Vanschoren, Joaquin; Rooijakkers, Michael J; Vullings, Rik; Aarts, Ronald M

    2016-08-01

    In this paper, we propose an algorithm that classifies whether a generated cardiac arrhythmia alarm is true or false. The large number of false alarms in intensive care is a severe issue. The noise peaks caused by alarms can be high and in a noisy environment nurses can experience stress and fatigue. In addition, patient safety is compromised because reaction time of the caregivers to true alarms is reduced. The data for the algorithm development consisted of records of electrocardiogram (ECG), arterial blood pressure, and photoplethysmogram signals in which an alarm for either asystole, extreme bradycardia, extreme tachycardia, ventricular fibrillation or flutter, or ventricular tachycardia occurs. First, heart beats are extracted from every signal. Next, the algorithm selects the most reliable signal pair from the available signals by comparing how well the detected beats match between different signals based on [Formula: see text]-score and selecting the best match. From the selected signal pair, arrhythmia specific features, such as heart rate features and signal purity index are computed for the alarm classification. The classification is performed with five separate Random Forest models. In addition, information on the local noise level of the selected ECG lead is added to the classification. The algorithm was trained and evaluated with the PhysioNet/Computing in Cardiology Challenge 2015 data set. In the test set the overall true positive rates were 93 and 95% and true negative rates 80 and 83%, respectively for events with no information and events with information after the alarm. The overall challenge scores were 77.39 and 81.58. PMID:27454128

  4. POPDC1S201F causes muscular dystrophy and arrhythmia by affecting protein trafficking

    Science.gov (United States)

    Schindler, Roland F.R.; Scotton, Chiara; Zhang, Jianguo; Passarelli, Chiara; Ortiz-Bonnin, Beatriz; Simrick, Subreena; Schwerte, Thorsten; Poon, Kar-Lai; Fang, Mingyan; Rinné, Susanne; Froese, Alexander; Nikolaev, Viacheslav O.; Grunert, Christiane; Müller, Thomas; Tasca, Giorgio; Sarathchandra, Padmini; Drago, Fabrizio; Dallapiccola, Bruno; Rapezzi, Claudio; Arbustini, Eloisa; Di Raimo, Francesca Romana; Neri, Marcella; Selvatici, Rita; Gualandi, Francesca; Fattori, Fabiana; Pietrangelo, Antonello; Li, Wenyan; Jiang, Hui; Xu, Xun; Bertini, Enrico; Decher, Niels; Wang, Jun; Brand, Thomas; Ferlini, Alessandra

    2015-01-01

    The Popeye domain–containing 1 (POPDC1) gene encodes a plasma membrane–localized cAMP-binding protein that is abundantly expressed in striated muscle. In animal models, POPDC1 is an essential regulator of structure and function of cardiac and skeletal muscle; however, POPDC1 mutations have not been associated with human cardiac and muscular diseases. Here, we have described a homozygous missense variant (c.602C>T, p.S201F) in POPDC1, identified by whole-exome sequencing, in a family of 4 with cardiac arrhythmia and limb-girdle muscular dystrophy (LGMD). This allele was absent in known databases and segregated with the pathological phenotype in this family. We did not find the allele in a further screen of 104 patients with a similar phenotype, suggesting this mutation to be family specific. Compared with WT protein, POPDC1S201F displayed a 50% reduction in cAMP affinity, and in skeletal muscle from patients, both POPDC1S201F and WT POPDC2 displayed impaired membrane trafficking. Forced expression of POPDC1S201F in a murine cardiac muscle cell line (HL-1) increased hyperpolarization and upstroke velocity of the action potential. In zebrafish, expression of the homologous mutation (popdc1S191F) caused heart and skeletal muscle phenotypes that resembled those observed in patients. Our study therefore identifies POPDC1 as a disease gene causing a very rare autosomal recessive cardiac arrhythmia and LGMD, expanding the genetic causes of this heterogeneous group of inherited rare diseases. PMID:26642364

  5. Single-Nucleotide Variations in Cardiac Arrhythmias: Prospects for Genomics and Proteomics Based Biomarker Discovery and Diagnostics

    Directory of Open Access Journals (Sweden)

    Ayman Abunimer

    2014-03-01

    Full Text Available Cardiovascular diseases are a large contributor to causes of early death in developed countries. Some of these conditions, such as sudden cardiac death and atrial fibrillation, stem from arrhythmias—a spectrum of conditions with abnormal electrical activity in the heart. Genome-wide association studies can identify single nucleotide variations (SNVs that may predispose individuals to developing acquired forms of arrhythmias. Through manual curation of published genome-wide association studies, we have collected a comprehensive list of 75 SNVs associated with cardiac arrhythmias. Ten of the SNVs result in amino acid changes and can be used in proteomic-based detection methods. In an effort to identify additional non-synonymous mutations that affect the proteome, we analyzed the post-translational modification S-nitrosylation, which is known to affect cardiac arrhythmias. We identified loss of seven known S-nitrosylation sites due to non-synonymous single nucleotide variations (nsSNVs. For predicted nitrosylation sites we found 1429 proteins where the sites are modified due to nsSNV. Analysis of the predicted S-nitrosylation dataset for over- or under-representation (compared to the complete human proteome of pathways and functional elements shows significant statistical over-representation of the blood coagulation pathway. Gene Ontology (GO analysis displays statistically over-represented terms related to muscle contraction, receptor activity, motor activity, cystoskeleton components, and microtubule activity. Through the genomic and proteomic context of SNVs and S-nitrosylation sites presented in this study, researchers can look for variation that can predispose individuals to cardiac arrhythmias. Such attempts to elucidate mechanisms of arrhythmia thereby add yet another useful parameter in predicting susceptibility for cardiac diseases.

  6. Short-Term Exposure to Air Pollution and Cardiac Arrhythmia: A Meta-Analysis and Systematic Review

    Directory of Open Access Journals (Sweden)

    Xuping Song

    2016-06-01

    Full Text Available The objective was to assess the transient association between air pollution and cardiac arrhythmia. Five databases were searched for studies investigating the association between daily increases in air pollutants (PM2.5, PM10, carbon monoxide, nitrogen dioxide, sulfur dioxide and ozone and arrhythmia hospitalization or arrhythmia mortality. Two reviewers independently selected studies, extracted data, and assessed risk of bias. Outcomes were analyzed via a random-effects model and reported as relative risk and 95% confidence interval. 25 studies satisfied our inclusion criteria and 23 contributed to the meta-analysis. Arrhythmia hospitalization or mortality were associated with increases in PM2.5 (RR = 1.015 per 10 μg/m3, 95% CI: 1.006–1.024, PM10 (RR = 1.009 per 10 μg/m3, 95% CI: 1.004–1.014, carbon monoxide (RR = 1.041 per 1 ppm, 95% CI: 1.017–1.065, nitrogen dioxide (RR = 1.036 per 10 ppb, 95% CI: 1.020–1.053, and sulfur dioxide (RR = 1.021 per 10 ppb, 95% CI: 1.003–1.039, but not ozone (RR = 1.012 per 10 ppb, 95% CI: 0.997–1.027. Both particulate and gaseous components, with the exception of ozone, have a temporal association with arrhythmia hospitalization or mortality. Compared with Europe and North America, a stronger association was noted in Asia.

  7. {sup 123}I-meta-iodobenzylguanidine myocardial scintigraphy in arrhythmia disease; La scintigraphie myocardique a la {sup 123}I-metaiodobenzylguanidine dans les arythmies

    Energy Technology Data Exchange (ETDEWEB)

    Valli, N.; Ducassou, D.; Barat, J.L. [Universite Victor-Segalen, Service de Medecine Nucleaire, Hopital du Haut-Leveque, 33 - Pessac (France)

    2007-12-15

    Meta-iodobenzylguanidine-iodine 123 ({sup 123}I-Mibg) myocardial scintigraphy is one of only the few methods available for the objective evaluation of cardiac sympathetic function at the clinical level. Disorders of cardiac sympathetic function play an important role in a variety of heart diseases and particularly arrhythmia disease. Mibg abnormalities have been described in various arrhythmia diseases. Their signification and their prognostic value are still not clear. This article focuses on reviewing the characteristics of {sup 123}I-Mibg myocardial scintigraphy in different arrhythmia diseases. (authors)

  8. Ranolazine, an antianginal agent, markedly reduces ventricular arrhythmias induced by ischemia and ischemia-reperfusion.

    Science.gov (United States)

    Dhalla, Arvinder K; Wang, Wei-Qun; Dow, Joan; Shryock, John C; Belardinelli, Luiz; Bhandari, Anil; Kloner, Robert A

    2009-11-01

    We tested the effect of the antianginal agent ranolazine on ventricular arrhythmias in an ischemic model using two protocols. In protocol 1, anesthetized rats received either vehicle or ranolazine (10 mg/kg, iv bolus) and were subjected to 5 min of left coronary artery (LCA) occlusion and 5 min of reperfusion with electrocardiogram and blood pressure monitoring. In protocol 2, rats received either vehicle or three doses of ranolazine (iv bolus followed by infusion) and 20 min of LCA occlusion. With protocol 1, ventricular tachycardia (VT) occurred in 9/12 (75%) vehicle-treated rats and 1/11 (9%) ranolazine-treated rats during reperfusion (P = 0.003). Sustained VT occurred in 5/12 (42%) vehicle-treated but 0/11 in ranolazine-treated rats (P = 0.037). The median number of episodes of VT during reperfusion in vehicle and ranolazine groups was 5.5 and 0, respectively (P = 0.0006); median duration of VT was 22.2 and 0 s in vehicle and ranolazine rats, respectively (P = 0.0006). With protocol 2, mortality in the vehicle group was 42 vs. 17% (P = 0.371), 10% (P = 0.162) and 0% (P = 0.0373) with ranolazine at plasma concentrations of 2, 4, and 8 microM, respectively. Ranolazine significantly reduced the incidence of ventricular fibrillation [67% in controls vs. 42% (P = 0.414), 30% (P = 0.198) and 8% (P = 0.0094) in ranolazine at 2, 4, and 8 microM, respectively]. Median number (2.5 vs. 0; P = 0.0431) of sustained VT episodes, incidence of sustained VT (83 vs. 33%, P = 0.0361), and the duration of VT per animal (159 vs. 19 s; P = 0.0410) were also significantly reduced by ranolazine at 8 microM. Ranolazine markedly reduced ischemia-reperfusion induced ventricular arrhythmias. Ranolazine demonstrated promising anti-arrhythmic properties that warrant further investigation. PMID:19767532

  9. Nicorandil prevents Gαq-induced progressive heart failure and ventricular arrhythmias in transgenic mice.

    Directory of Open Access Journals (Sweden)

    Masamichi Hirose

    Full Text Available BACKGROUND: Beneficial effects of nicorandil on the treatment of hypertensive heart failure (HF and ischemic heart disease have been suggested. However, whether nicorandil has inhibitory effects on HF and ventricular arrhythmias caused by the activation of G protein alpha q (Gα(q -coupled receptor (GPCR signaling still remains unknown. We investigated these inhibitory effects of nicorandil in transgenic mice with transient cardiac expression of activated Gα(q (Gα(q-TG. METHODOLOGY/PRINCIPAL FINDINGS: Nicorandil (6 mg/kg/day or vehicle was chronically administered to Gα(q-TG from 8 to 32 weeks of age, and all experiments were performed in mice at the age of 32 weeks. Chronic nicorandil administration prevented the severe reduction of left ventricular fractional shortening and inhibited ventricular interstitial fibrosis in Gα(q-TG. SUR-2B and SERCA2 gene expression was decreased in vehicle-treated Gα(q-TG but not in nicorandil-treated Gα(q-TG. eNOS gene expression was also increased in nicorandil-treated Gα(q-TG compared with vehicle-treated Gα(q-TG. Electrocardiogram demonstrated that premature ventricular contraction (PVC was frequently (more than 20 beats/min observed in 7 of 10 vehicle-treated Gα(q-TG but in none of 10 nicorandil-treated Gα(q-TG. The QT interval was significantly shorter in nicorandil-treated Gα(q-TG than vehicle-treated Gα(q-TG. Acute nicorandil administration shortened ventricular monophasic action potential duration and reduced the number of PVCs in Langendorff-perfused Gα(q-TG mouse hearts. Moreover, HMR1098, a blocker of cardiac sarcolemmal K(ATP channels, significantly attenuated the shortening of MAP duration induced by nicorandil in the Gα(q-TG heart. CONCLUSIONS/SIGNIFICANCE: These findings suggest that nicorandil can prevent the development of HF and ventricular arrhythmia caused by the activation of GPCR signaling through the shortening of the QT interval, action potential duration, the normalization

  10. Arrhythmias and conduction abnormalities in children after repair of tetralogy of Fallot

    Directory of Open Access Journals (Sweden)

    Kuzevska-Maneva Konstandina

    2005-01-01

    Full Text Available Aim. To find out types and frequency of cardiac arrhythmias and conduction abnormalities in the group of children who underwent surgery for tetralogy of Fallot (TOF. Methods. Fortysix pedicatric patients who underwent a complete repair of TOF at the age of 1 to 13 (mean 2.89 ± 2.36 were studied. Thirty-eight (82.60% had total correction and 8 (17.40% had palliative operation first, and total correction afterwards. Twenty-four-hour Holter ECG monitoring was performed in all 46 pediatric patients aged from 1 to 16 yrs (mean 6.48 ± 4.04 after surgery as follows: in 1 patient (2.17% after a year, in 20 patients (43.47% after 2 to 5 years and in 25 patients (54.34% after 5 years. Mean age of patients on Holter monitoring was 9.25 ± 4.39 (range 4−19. Twenty of them (43.47% were girls and 28 (56.53% were boys. All the patients were evaluated by standard methods (clinical signs, clinical findings, ECG before surgery, ECG before Holter monitoring and 2D Doppler echocardiography. Results. Types of heart rhythm found out by Holter monitoring were: sinus nodus dysfunction in 1 child (2.17%, significant premature atrial contraction (PAC in 8 (17.39%, supraventricular paroxysmal tachycardia in 3 (6.53%, transient nodal rhythm in 2 (4.34%, premature ventricular contraction (PVC Lown grade I-III in 9 (19.56% and Lown grade IV in 2 (4.34, atrioventricular (AV block grade I in 2, right bundle branch block (RBBB in all 46 (100% and RBBB + left anterior hemiblock (LAH in 4 (8.96%. There was no presence of atrial flutter, ventricular tachycardia or complete AV block. None of them experienced sudden death. Using cross procedure statistical methods, it was found that all the patients with PVC had right ventricular dilatation. There was no relation of other types of arrhythmia found on Holter monitoring to the other parameters from echocardiography, neither to the other standard methods. Children did not need the pace-maker, but 36.95% of the them required

  11. Particles Alter Diesel Exhaust Gases-Induced Hypotension, Cardiac Arrhythmia,Conduction Disturbance, and Autonomic Imbalance in Heart Failure-Prone Rats

    Science.gov (United States)

    Epidemiologic studies indicate that acute exposures to vehicular traffic and particulate matter (PM) air pollution are key causes of fatal cardiac arrhythmia, especially in those with preexisting cardiovascular disease. Researchers point to electrophysiologic dysfunction and auto...

  12. A challenging case of ventricular arrhythmia in a patient with myocarditis: ICD yes/no after ablation

    Directory of Open Access Journals (Sweden)

    Maria L Narducci; Teresa Rio; Francesco Perna; Domenico D�Amario; Biagio Merlino; Riccardo Marano; Gianluigi Bencardino; Frediano Inzani; Gemma Pelargonio; Filippo Crea

    2014-10-01

    Full Text Available In patients with myocarditis, early diagnosis and appropriate therapy are mandatory, as well as close clinical and strumental follow-up with particular regard on progression of disease and ventricular arrhythmias relapse. The management of ventricular arrhythmias should follow current guidelines for ICD implantation, but new therapeutic options could be evaluated in these patients as combined epicardial/endocardial ablation and external wereable defibrillator. Particularly, left ventricular ejection fraction (LVEF represented the only risk stratifier for sudden cardiac death currently used in myocarditis, although the use of single risk factor have limited utility. On this regard, combined analysis of structural myocardial tissue definition by cardiac magnetic resonance (CMR and endomyocardial biopsy, in association with resting cardiac systolic function could improve predictive accuracy for sudden death in patients with myocarditis.

  13. Effect of sodium nitrite on ischaemia and reperfusion-induced arrhythmias in anaesthetized dogs: is protein S-nitrosylation involved?

    Directory of Open Access Journals (Sweden)

    Mária Kovács

    Full Text Available To provide evidence for the protective role of inorganic nitrite against acute ischaemia and reperfusion-induced ventricular arrhythmias in a large animal model.Dogs, anaesthetized with chloralose and urethane, were administered intravenously with sodium nitrite (0.2 µmol kg(-1 min(-1 in two protocols. In protocol 1 nitrite was infused 10 min prior to and during a 25 min occlusion of the left anterior descending (LAD coronary artery (NaNO2-PO; n = 14, whereas in protocol 2 the infusion was started 10 min prior to reperfusion of the occluded vessel (NaNO2-PR; n = 12. Control dogs (n = 15 were infused with saline and subjected to the same period of ischaemia and reperfusion. Severities of ischaemia and ventricular arrhythmias, as well as changes in plasma nitrate/nitrite (NOx levels in the coronary sinus blood, were assessed throughout the experiment. Myocardial superoxide and nitrotyrosine (NT levels were determined during reperfusion. Changes in protein S-nitrosylation (SNO and S-glutathionylation were also examined.Compared with controls, sodium nitrite administered either pre-occlusion or pre-reperfusion markedly suppressed the number and severity of ventricular arrhythmias during occlusion and increased survival (0% vs. 50 and 92% upon reperfusion. There were also significant decreases in superoxide and NT levels in the nitrite treated dogs. Compared with controls, increased SNO was found only in NaNO2-PR dogs, whereas S-glutathionylation occurred primarily in NaNO2-PO dogs.Intravenous infusion of nitrite profoundly reduced the severity of ventricular arrhythmias resulting from acute ischaemia and reperfusion in anaesthetized dogs. This effect, among several others, may result from an NO-mediated reduction in oxidative stress, perhaps through protein SNO and/or S-glutathionylation.

  14. Increased Short-Term Variability of the QT Interval in Professional Soccer Players: Possible Implications for Arrhythmia Prediction

    OpenAIRE

    Lengyel, Csaba; Orosz, Andrea; Hegyi, Péter; Komka, Zsolt; Udvardy, Anna; Bosnyák, Edit; Trájer, Emese; Pavlik, Gábor; Tóth, Miklós; Wittmann, Tibor; Papp, Julius Gy; Varró, András; Baczkó, István

    2011-01-01

    Background Sudden cardiac death in competitive athletes is rare but it is significantly more frequent than in the normal population. The exact cause is seldom established and is mostly attributed to ventricular fibrillation. Myocardial hypertrophy and slow heart rate, both characteristic changes in top athletes in response to physical conditioning, could be associated with increased propensity for ventricular arrhythmias. We investigated conventional ECG parameters and temporal short-term bea...

  15. Mechanical Dyssynchrony by Tissue Doppler Cross-Correlation is Associated with Risk for Complex Ventricular Arrhythmias after Cardiac Resynchronization Therapy

    DEFF Research Database (Denmark)

    Tayal, Bhupendar; Gorcsan, John; Delgado-Montero, Antonia;

    2015-01-01

    BACKGROUND: Tissue Doppler cross-correlation analysis has been shown to be associated with long-term survival after cardiac resynchronization defibrillator therapy (CRT-D). Its association with ventricular arrhythmia (VA) is unknown. METHODS: From two centers 151 CRT-D patients (New York Heart.......0; 95% CI, 1.8-13.5; P = .002). CONCLUSIONS: Persistent and new mechanical dyssynchrony after CRT-D was associated with subsequent complex VA. Dyssynchrony after CRT-D is a marker of poor prognosis....

  16. Pharmacological modulation of gap junction function with the novel compound rotigaptide: a promising new principle for prevention of arrhythmias.

    Science.gov (United States)

    Kjølbye, Anne Louise; Haugan, Ketil; Hennan, James K; Petersen, Jørgen S

    2007-10-01

    Existing anti-arrhythmic therapy is hampered by lack of efficacy and unacceptable side effects. Thus, ventricular tachycardia and fibrillation remains the strongest predictor of in-hospital mortality in patients with myocardial infarction. In atrial fibrillation, rhythm control with conventional ion channel blockers provide no therapeutic benefit relative to rate control. Several lines of research indicate that impaired gap junctional cell-to-cell coupling between neighbouring cardiomyocytes is critical for the development of cardiac re-entry arrhythmias. Rotigaptide is the first drug that has been developed to prevent arrhythmias by re-establishing gap junctional intercellular communication. During conditions with acute cardiac ischaemia, rotigaptide effectively prevents induction of both ventricular and atrial tachyarrhythmia. Moreover, rotigaptide effectively prevents ischaemia reperfusion arrhythmias. At the cellular level, rotigaptide inhibits ischaemia-induced dephosphorylation of Ser297 and Ser368, which is considered important for the gating of connexin43 gap junction channels. No drug-related toxicity has been demonstrated at plasma concentrations 77,000 times above therapeutic concentrations. In rats and dogs, rotigaptide reduces infarct size following myocardial infarction. A series of phase I trials has been completed in which rotigaptide has been administered intravenously to ~200 healthy persons. No drug-related side effects have been demonstrated in healthy human beings. Clinical safety, tolerability and efficacy in patients with heart disease are being evaluated in ongoing clinical trials. Rotigaptide represents a pioneering pharmacological principle with a highly favourable preclinical and clinical safety profile, which makes this molecule a promising drug candidate for the prevention of cardiac arrhythmias.

  17. Cardiac sympathetic denervation in patients with refractory ventricular arrhythmias or electrical storm: Intermediate and long-term follow-up

    OpenAIRE

    Vaseghi, M; Gima, J; Kanaan, C; Ajijola, OA; Marmureanu, A; Mahajan, A.; Shivkumar, K

    2014-01-01

    Background Left and bilateral cardiac sympathetic denervation (CSD) have been shown to reduce burden of ventricular arrhythmias acutely in a small number of patients with ventricular tachyarrhythmia (VT) storm. The effects of this procedure beyond the acute setting are unknown. Objective The purpose of this study was to evaluate the intermediate and long-term effects of left and bilateral CSD in patients with cardiomyopathy and refractory VT or VT storm. Methods Retrospective analysis of medi...

  18. HEART RHYTHM DISORDERS IN NEW-BORNS AND INFANTS: CLINICAL COURSE AND PERINATAL RISK FACTORS OF ARRHYTHMIAS APPEARANCE

    Directory of Open Access Journals (Sweden)

    I. A. Kovalyov

    2013-01-01

    Full Text Available Clinical course, prognosis and mechanisms of separate forms of heart rhythm disorders in children differ from those in adults. Especially, it refers to new-borns and infants whose conduction system differs by functional and morphologic immaturity. In connection with it, the assessment of natural history of heart rhythm disorders, occurred in a perinatal period, and determination of risk factors of arrhythmia appearance in infants are of some interest. 88 newborns took part in the study. The patients were involved by continuous sampling technique. Risk factors, occurred in a perinatal period and potentially influenced on development of heart rhythm disorders, were assessed. In our study we took biological, gynecologic and obstetric history, data of gestation and delivery course, early and late neonatal period, early infancy, Echo, neurosonography, Holter monitoring with determination of heart rhythm variability, and determined thyroid hormonal status. Maximum specific gravity had extrasystoles – 32.4% – in the structure of idiopathic arrhythmias in infants. Heart rhythm disorders with natural history were kept at six months of life only in 5,4% of children. Persistence of arrhythmias was marked during one year only for WPW syndrome. Heart rhythm disorders are often marked significantly in children whose mothers had acute respiratory disease during the pregnancy, or if the children were born from the first pregnancy, had the signs of central nervous system damage syndromes in an early perinatal period (arrest, intracranial hypertension, convulsive disorder. Disorders of autonomic imbalance of cardiac function and peculiarities of hemodynamics of pulmonary circulation contribute significantly into appearance and persistence of all types of arrhythmias. On the whole, the prognosis of heart rhythm disorders, occurred in the perinatal period, without organic and structural changes of myocardium is favorable. The exclusion can be made for

  19. Effects of Org 7797 on early, late and inducible arrhythmias following coronary artery occlusion in rats and dogs.

    OpenAIRE

    Winslow, E.; Campbell, J K; Barron, E; Marshall, R J; Muir, A. W

    1991-01-01

    1. The class Ic steroidal antiarrhythmic agent, Org 7797, was compared with two other Ic agents, flecainide and propafenone for intravenous activity against ischaemia-related cardiac arrhythmias and for electrophysiological actions in vivo. In addition the haemodynamic effects of Org 7797 were assessed in greyhounds. 2. Org 7797 (0.5 mg kg-1) significantly reduced the expected incidence of early ischaemia-induced ventricular fibrillation (VF) in rats and greyhound dogs and at doses of 0.5-1.0...

  20. Prevalence of unknown and untreated arrhythmias in an older outpatient population screened by wireless long-term recording ECG

    OpenAIRE

    Lindberg, Terese; Bohman, Doris; Elmstahl, Solve; Jogréus,Claes; Sanmartin Berglund,Johan

    2016-01-01

    Terese Lindberg,1,2 Doris M Bohman,1 Sölve Elmståhl,2 Claes Jogréus,1 Johan Sanmartin Berglund1 1Department of Health, Blekinge Institute of Technology, Karlskrona, 2Department of Health Sciences, Lund University, Lund, Sweden Purpose: With longer life expectancies, the prevalence of arrhythmias is increasing; thus, there is a need for new methods to screen the older outpatient population. This population-based study describes the prevalence of arrhyth...

  1. Effects of KR-32570, a new sodium hydrogen exchanger inhibitor, on myocardial infarction and arrhythmias induced by ischemia and reperfusion.

    Science.gov (United States)

    Lee, Byung Ho; Yi, Kyu Yang; Lee, Sunkyung; Lee, Sunghou; Yoo, Sung-eun

    2005-10-31

    The present study was performed to evaluate the cardioprotective effects of [5-(2-methoxy-5-chloro-5-phenyl)furan-2-ylcarbonyl]guanidine (KR-32570) in rat and dog models of coronary artery occlusion and reperfusion. In addition, we sought to clarify the efficacy of KR-32570 on reperfusion-induced fatal ventricular arrhythmia. In anesthetized rats subjected to 45-min coronary occlusion and 90-min reperfusion, KR-32570 (i.v. bolus) dose-dependently reduced myocardial infarct size from 58.0% to 50.7%, 35.3%, 33.5% and 27.0% for 0.03, 0.1, 0.3 and 1.0 mg/kg, respectively (PKR-32570 (3 mg/kg, i.v. bolus) markedly decreased infarct size from 28.9% in vehicle-treated group to 8.0% (PKR-32570 dose-dependently decreased the incidence of premature ventricular contraction, ventricular tachycardia or ventricular fibrillation induced by ischemia and reperfusion in rats. Similar results were obtained in dogs with reperfusion-induced arrhythmia. In separate experiments to assess the effects of timing of treatment, KR-32570 given 10 min before or at reperfusion in rat models also significantly reduced the myocardial infarct size (40.9% and 46.1%, respectively) compared with vehicle-treated group. In all studies, KR-32570 caused no significant changes in any hemodynamic profiles. Taken together, these results indicate that KR-32570 significantly reduced the myocardial infarction and incidence of arrhythmias induced by ischemia and reperfusion in rats and dogs, without affecting hemodynamic profiles. Thus, it could be potentially useful in the prevention and treatment of myocardial injuries and lethal ventricular arrhythmias.

  2. Development of a patch type embedded cardiac function monitoring system using dual microprocessor for arrhythmia detection in heart disease patient.

    Science.gov (United States)

    Jang, Yongwon; Noh, Hyung Wook; Lee, I B; Jung, Ji-Wook; Song, Yoonseon; Lee, Sooyeul; Kim, Seunghwan

    2012-01-01

    A patch type embedded cardiac function monitoring system was developed to detect arrhythmias such as PVC (Premature Ventricular Contraction), pause, ventricular fibrillation, and tachy/bradycardia. The overall system is composed of a main module including a dual processor and a Bluetooth telecommunication module. The dual microprocessor strategy minimizes power consumption and size, and guarantees the resources of embedded software programs. The developed software was verified with standard DB, and showed good performance.

  3. Life-threatening arrhythmia verification in ICU patients using the joint cardiovascular dynamical model and a Bayesian filter.

    Science.gov (United States)

    Sayadi, Omid; Shamsollahi, Mohammad B

    2011-10-01

    In this paper, a novel nonlinear joint dynamical model is presented, which is based on a set of coupled ordinary differential equations of motion and a Gaussian mixture model representation of pulsatile cardiovascular (CV) signals. In the proposed framework, the joint interdependences of CV signals are incorporated by assuming a unique angular frequency that controls the limit cycle of the heart rate. Moreover, the time consequence of CV signals is controlled by the same phase parameter that results in the space dimensionality reduction. These joint equations together with linear assignments to observation are further used in the Kalman filter structure for estimation and tracking. Moreover, we propose a measure of signal fidelity by monitoring the covariance matrix of the innovation signals throughout the filtering procedure. Five categories of life-threatening arrhythmias were verified by simultaneously tracking the signal fidelity and the polar representation of the CV signal estimations. We analyzed data from Physiobank multiparameter databases (MIMIC I and II). Performance evaluation results demonstrated that the sensitivity of the detection ranges over 93.50% and 100.00%. In particular, the addition of more CV signals improved the positive predictivity of the proposed method to 99.27% for the total arrhythmic types. The method was also used for false arrhythmia suppression issued by ICU monitors, with an overall false suppression rate reduced from 42.3% to 9.9%. In addition, false critical ECG arrhythmia alarm rates were found to be, on average, 42.3%, with individual rates varying between 16.7% and 86.5%. The results illustrate that the method can contribute to, and enhance the performance of clinical life-threatening arrhythmia detection. PMID:21324772

  4. A statistical index for early diagnosis of ventricular arrhythmia from the trend analysis of ECG phase-portraits

    OpenAIRE

    Cappiello, Grazia; Das, Saptarshi; Mazomenos, Evangelos; Maharatna, Koushik; Koulaouzidis, George; Morgan, John M.; Puddu, Paolo Emilio

    2015-01-01

    In this paper, we propose a novel statistical index for the early diagnosis of ventricular arrhythmia (VA) using the time delay phase-space reconstruction (PSR) technique, from the electrocardiogram (ECG) signal. Patients with two classes of fatal VA - with preceding ventricular premature beats (VPBs) and with no VPBs have been analysed using extensive simulations. Three subclasses of VA with VPBs viz. ventricular tachycardia (VT), ventricular fibrillation (VF) and VT followed by VF are analy...

  5. Analysis of human electrocardiogram for arrhythmia auto-classification and biometric recognition systems using analytic and autoregressive modeling parameters

    OpenAIRE

    Alhamdi, Mustafa

    2015-01-01

    The electrocardiogram is a skin surface measurement of the electrical activity of the heart over time. This activity is detected by electrodes attached to the surface of the skin and recorded or displayed by an external medical device. Doctors use electrocardiograms to detect and diagnose conditions such as arrhythmias (abnormal heart rhythms) and myocardial infarctions (heartattacks). The work described in this thesis investigates the system designed for two primary applications, electrocard...

  6. Resetting and Entrainment of Reentrant Arrhythmias: Part I: Concepts, Recognition, and Protocol for Evaluation: Surface ECG versus Intracardiac Recordings

    OpenAIRE

    Almendral, Jesús; CAULIER-CISTERNA, RAÚL; Rojo-Álvarez, José Luis

    2013-01-01

    In this paper, we review the information accumulated over the years regarding the phenomena of resetting and entrainment of reentrant arrhythmias. Over three decades of research and clinical applications, these phenomena have demonstrated that they stay as a main tool for an intellectual understanding of reentry and to base strategies for localization of critical areas for ablative therapies. This review will be divided into two parts. This first part deals with the bases for the concept deve...

  7. Use of Intravenous Amiodarone in the Treatment of Nifekalant-Resistant Arrhythmia: A Review of 11 Consecutive Cases with Severe Heart Failure

    Directory of Open Access Journals (Sweden)

    Tohru Ujihira

    2011-05-01

    Full Text Available Background: Both nifekalant hydrochloride (NIF, a selective IKr blocker, and intravenous amiodarone (AMD, a multi-channel (including IKr blocking blocker, have been reported to be efficacious for refractory arrhythmias. However, the optimal use of those antiarrhythmic drugs for refractory arrhythmia with severe heart failure has not been established. Intravenous AMD might be effective for arrhythmias refractory to NIF in patients with severe heart failure. Here, we report that intravenous amiodarone was effective in the treatment of nifekalant-resistant in a group of arrhythmia patients with severe heart failure. Methods: Eleven severe heart failure patients who had received intravenous AMD for treatment of NIF-resistant arrhythmias were included in this study, and retrospective analysis was performed. Clinical efficacy (terminative and preventive effects on arrhythmia of intravenous AMD was evaluated. Results: All cases were emergent cases and had depressed left ventricular ejection fraction (30 ± 13%. Clinical arrhythmias were ventricular fibrillation (VF in four patients, ventricular tachycardia (VT in six patients, and atrial fibrillation (AF in one patient. NIF was administered to all patients by intravenous injection. After administration of NIF, VT/VF/AF was terminated in seven of the 10 patients, but a preventive effect was not obtained in any of the patients (NIF-resistance. Intravenous AMD (maintenance dose: 484 ± 166 mg/day was effective both in termination (80% and in prevention (80% of VT/VF events in those patients. It was also effective in termination (80% and prevention (60% of AF events refractory to NIF. During continuous AMD administration, no significant adverse effects or proarrhythmic effects were observed in any of the patients. Five patients died within one month, but there was no arrhythmic deaths. Conclusions: Intravenous AMD was effective in NIF-resistant lethal arrhythmias and was relatively safe in emergent cases

  8. Effects of exogenous oxygen derived free radicals on myocardial capillary permeability, vascular tone, and incidence of ventricular arrhythmias in the canine heart

    DEFF Research Database (Denmark)

    Svendsen, Jesper Hastrup; Bjerrum, P J

    1992-01-01

    The aim was to examine the effects of exogenous oxygen derived free radicals on myocardial capillary permeability for a small hydrophilic indicator, postischaemic vascular tone, and the occurrence of arrhythmias in the canine heart in vivo.......The aim was to examine the effects of exogenous oxygen derived free radicals on myocardial capillary permeability for a small hydrophilic indicator, postischaemic vascular tone, and the occurrence of arrhythmias in the canine heart in vivo....

  9. Prevalence of arrhythmias among children below 15 years of age with congenital heart diseases attending Mulago National Referral Hospital, Uganda

    OpenAIRE

    Batte, Anthony; Lwabi, Peter; Lubega, Sulaiman; Kiguli, Sarah; Nabatte, Violette; Karamagi, Charles

    2016-01-01

    Background In Uganda, few children with congenital heart diseases (CHD) benefit from early corrective cardiac surgery. These children are at high risk of developing heart failure and electrolyte imbalances; factors which increase their risk of developing arrhythmias. This study aimed to determine the prevalence and factors associated with arrhythmias among children with congenital heart diseases receiving care at Mulago Hospital. Methods This was a cross-sectional study carried out from Augus...

  10. Using Mixture Structures of Neural Networks in Order to Detect Cardiac Arrhythmias Using Fusion of Temporal and Wavelet Features

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    syed mohammd Razavi

    2011-05-01

    Full Text Available In recent years the use of intelligent systems in science and engineering, especially in the diagnosis of disease, is increasingly growing. In this paper a smart way to diagnose heart disease (cardiac arrhythmias is presented. This method is based on a combination of structures using neural networks for classification of normal operation and four abnormal heart functions. In the combination of these structures, some neural networks as a mediator, and some of them have been used as a specialist. In the proposed method firstly for removing noise from ECG signal, preprocessing was performed. The various time features (including fifteen properties and wavelet features (includes fifteen feature are extracted from the noise free signal and given the large number of selected features, principal components analysis is used for feature reduction to eight features. The proposed structures of MLP neural networks and RBF neural networks are appropriately trained for classification of arrhythmias and their performance has been evaluated. The results of the implementation of the proposed method on MIT / BIH database show the better performance in the diagnosis of cardiac arrhythmias compared to previous approaches.

  11. Acute and Chronic Changes and Predictive Value of Tpeak-Tend for Ventricular Arrhythmia Risk in Cardiac Resynchronization Therapy Patients

    Science.gov (United States)

    Xue, Cong; Hua, Wei; Cai, Chi; Ding, Li-Gang; Liu, Zhi-Min; Fan, Xiao-Han; Zhao, Yun-Zi; Zhang, Shu

    2016-01-01

    Background: Prolongation of the Tpeak-Tend (TpTe) interval as a measurement of transmural dispersion of repolarization (TDR) is an independent risk factor for chronic heart failure mortality. However, the cardiac resynchronization therapy's (CRT) effect on TDR is controversial. Therefore, this study aimed to evaluate CRTs acute and chronic effects on repolarization dispersion. Furthermore, we aimed to investigate the relationship between TpTe changes and ventricular arrhythmia. Methods: The study group consisted of 101 patients treated with CRT-defibrillator (CRT-D). According to whether TpTe was shortened, patients were grouped at immediate and 1-year follow-up after CRT, respectively. The echocardiogram index and ventricular arrhythmia were observed and compared in these subgroups. Results: For all patients, TpTe slightly increased immediately after CRT-D implantation, and then decreased at the 1-year follow-up (from 107 ± 23 to 110 ± 21 ms within 24 h, to 94 ± 24 ms at 1-year follow-up, F = 19.366, P arrhythmia. PMID:27625093

  12. Exercise-induced ventricular arrhythmias and vagal dysfunction in Chagas disease patients with no apparent cardiac involvement

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    Henrique Silveira Costa

    2015-04-01

    Full Text Available INTRODUCTION : Exercise-induced ventricular arrhythmia (EIVA and autonomic imbalance are considered as early markers of heart disease in Chagas disease (ChD patients. The objective of the present study was to verify the differences in the occurrence of EIVA and autonomic maneuver indexes between healthy individuals and ChD patients with no apparent cardiac involvement. METHODS : A total of 75 ChD patients with no apparent cardiac involvement, aged 44.7 (8.5 years, and 38 healthy individuals, aged 44.0 (9.2 years, were evaluated using echocardiography, symptom-limited treadmill exercise testing and autonomic function tests. RESULTS : The occurrence of EIVA was higher in the chagasic group (48% than in the control group (23.7% during both the effort and the recovery phases. Frequent ventricular contractions occurred only in the patient group. Additionally, the respiratory sinus arrhythmia index was significantly lower in the chagasic individuals compared with the control group. CONCLUSIONS : ChD patients with no apparent cardiac involvement had a higher frequency of EIVA as well as more vagal dysfunction by respiratory sinus arrhythmia. These results suggest that even when asymptomatic, ChD patients possess important arrhythmogenic substrates and subclinical disease.

  13. Protective effects of Ping-Lv-Mixture (PLM), a medicinal formula on arrhythmias induced by myocardial ischemia-reperfusion.

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    An, Wei; Yang, Jing

    2006-11-01

    Ping-Lv-Mixture (PLM) is a Chinese medicinal formula. The present study aimed to determine the effects of PLM on myocardial ischemia-reperfusion (MI/R) induced arrhythmias in rats. Arrhythmia model was established by occlusion of the left arterial descending coronary artery and thereafter reperfusion. A lead II electrocardiogram was monitored throughout the experiment. The results showed that pretreatment of PLM to MI/R rats significantly reduced the incidence and duration of ventricular tachycardia and ventricular fibrillation. On induction of MI/R, the activities of creatine kinase and lactate dehydrogenase were increased in vehicle group. PLM (0.04-1.00 g/kg) administration prevented the increase of these enzymes. Moreover, a significant increase of myocardium superoxide dismutase and decrease of malondialdehyde contents were observed in rats of PLM groups. On the other hand, the expressions of platelet activating factor (PAF) receptor mRNA was down-regulated in a dose-dependent manner in the PLM-treated groups by RT-PCR. Thus, it can be concluded that pretreatment with PLM inhibited lipid peroxidation in rats through suppressing the expression of PAF receptor, which may contribute to its preventive effect on myocardial ischemia-reperfusion induced arrhythmias.

  14. Identifying potential functional impact of mutations and polymorphisms: Linking heart failure, increased risk of arrhythmias and sudden cardiac death.

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    BENOIT eJAGU

    2013-09-01

    Full Text Available Researchers and clinicians have discovered several important concepts regarding the mechanisms responsible for increased risk of arrhythmias, heart failure and sudden cardiac death. One major step in defining the molecular basis of normal and abnormal cardiac electrical behaviour has been the identification of single mutations that greatly increase the risk for arrhythmias and sudden cardiac death by changing channel-gating characteristics. Indeed, mutations in several genes encoding ion channels, such as SCN5A, which encodes the major cardiac Na+ channel, have emerged as the basis for a variety of inherited cardiac arrhythmias such as long QT syndrome, Brugada syndrome, progressive cardiac conduction disorder, sinus node dysfunction or sudden infant death syndrome. In addition, genes encoding ion channel accessory proteins, like anchoring or chaperone proteins, which modify the expression, the regulation of endocytosis and the degradation of ion channel α-subunits have also been reported as susceptibility genes for arrhythmic syndromes. The regulation of ion channel protein expression also depends on a fine-tuned balance among different other mechanisms, such as gene transcription, RNA processing, post-transcriptional control of gene expression by miRNA, protein synthesis, assembly and post-translational modification and trafficking.

  15. A statistical index for early diagnosis of ventricular arrhythmia from the trend analysis of ECG phase-portraits.

    Science.gov (United States)

    Cappiello, Grazia; Das, Saptarshi; Mazomenos, Evangelos B; Maharatna, Koushik; Koulaouzidis, George; Morgan, John; Puddu, Paolo Emilio

    2015-01-01

    In this paper, we propose a novel statistical index for the early diagnosis of ventricular arrhythmia (VA) using the time delay phase-space reconstruction (PSR) technique, from the electrocardiogram (ECG) signal. Patients with two classes of fatal VA-with preceding ventricular premature beats (VPBs) and with no VPBs-have been analysed using extensive simulations. Three subclasses of VA with VPBs viz. ventricular tachycardia (VT), ventricular fibrillation (VF) and VT followed by VF are analyzed using the proposed technique. Measures of descriptive statistics like mean (µ), standard deviation (σ), coefficient of variation (CV = σ/µ), skewness (γ) and kurtosis (β) in phase-space diagrams are studied for a sliding window of 10 beats of the ECG signal using the box-counting technique. Subsequently, a hybrid prediction index which is composed of a weighted sum of CV and kurtosis has been proposed for predicting the impending arrhythmia before its actual occurrence. The early diagnosis involves crossing the upper bound of a hybrid index which is capable of predicting an impending arrhythmia 356 ECG beats, on average (with 192 beats standard deviation) before its onset when tested with 32 VA patients (both with and without VPBs). The early diagnosis result is also verified using a leave one out cross-validation (LOOCV) scheme with 96.88% sensitivity, 100% specificity and 98.44% accuracy. PMID:25500749

  16. Classification of Arrhythmias Using Linear Predictive Coefficients and Probabilistic Neural Network

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    Hossein EBRAHIMNEZHAD

    2013-09-01

    Full Text Available Cardiac arrhythmia, which means abnormality of heart rhythm, in fact refers to disorder in electrical conduction system of the heart. The aim of this paper is to present a classifier system based on Probabilistic Neural Networks in order to detect and classify abnormal heart rates, where besides its simplicity, has high resolution capability. The proposed algorithm has three stages. At first, the electrocardiogram signals impose into preprocessing block. After preprocessing and noise elimination, the exact position of R peak is detected by multi resolution wavelet analysis. In the next step, the extracted linear predictive coefficients (LPC of QRS complex will enter in to the classification block as an input. A Support Vector Machine classifier is developed in parallel to verify and measure the PNN classifier’s success. The experiments were conducted on the ECG data from the MIT-BIH database to classify four kinds of abnormal waveforms and normal beats such as Normal sinus rhythm, Atrial premature contraction (APC, Right bundle branch block (RBBB and Left bundle branch block (LBBB. The results show 92.9% accuracy and 93.17% sensitivity

  17. Coregulation of respiratory sinus arrhythmia between parents and preschoolers: differences by children's externalizing problems.

    Science.gov (United States)

    Lunkenheimer, Erika; Tiberio, Stacey S; Buss, Kristin A; Lucas-Thompson, Rachel G; Boker, Steven M; Timpe, Zachary C

    2015-12-01

    The coordination of physiological processes between parents and infants is thought to support behaviors critical for infant adaptation, but we know little about parent-child physiological coregulation during the preschool years. The present study examined whether time-varying changes in parent and child respiratory sinus arrhythmia (RSA) exhibited coregulation (across-person dynamics) accounting for individual differences in parent and child RSA, and whether there were differences in these parasympathetic processes by children's externalizing problems. Mother-child dyads (N = 47; Child age M = 3½ years) engaged in three laboratory tasks (free play, clean up, puzzle task) for 18 min, during which RSA data were collected. Multilevel coupled autoregressive models revealed that mothers and preschoolers showed positive coregulation of RSA such that changes in mother RSA predicted changes in the same direction in child RSA and vice versa, controlling for the stability of within-person RSA over time and individual differences in overall mean RSA. However, when children's externalizing behaviors were higher, coregulation was negative such that changes in real-time mother and child RSA showed divergence rather than positive concordance. Results suggest that mothers and preschoolers do coregulate RSA during real-time interactions, but that children's higher externalizing behavior problems are related to disruptions in these processes. PMID:25976070

  18. An organized approach to the localization, mapping, and ablation of outflow tract ventricular arrhythmias.

    Science.gov (United States)

    Hutchinson, Mathew D; Garcia, Fermin C

    2013-10-01

    The outflow tract (OT) regions of the right and left ventricles, common sites of origin for idiopathic ventricular arrhythmias (VA), have complex three-dimensional anatomical relationships. The understanding of in situ or "attitudinal" relationships not only informs the electrocardiographic interpretation of VA site of origin, but also facilitates their catheter-based mapping and ablation strategies. By viewing each patient as his or her own "control," the expected changes in ECG morphology (i.e., frontal plane QRS axis and precordial transition) between adjacent intracardiac structures (e.g., RVOT and aortic root) can be reliably predicted. Successful mapping of OT VAs involve a combination of activation and pacemapping guided by fluoroscopy, electroanatomical mapping, and intracardiac echocardiography. The purpose of this manuscript is to provide a simple, reliable strategy for catheter based mapping and ablation of OT VAs. We also discuss 2 specific challenges in OT VA mapping: (1) differentiating posterior RVOT from right coronary cusp VA origin; and (2) mapping VAs originating from the LV summit.

  19. Cardiac arrhythmia in Wilson′s disease: An oversighted and overlooked entity!

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    Bhupender Kumar Bajaj

    2016-01-01

    Full Text Available Wilson's disease is a multisystem disorder which manifests with hepatic, neurological, musculoskeletal, hematological, renal, and cardiac symptoms. The hepatic and neurological manifestations often overshadow the other system involvement including cardiac symptoms and signs, which may prove fatal. We report a case of a young female who presented with progressive parkinsonian features and dystonia for around 4 months followed 2 months later by the complaint of episodes of light-headedness. She was diagnosed to have Wilson's disease based on the presence of Kayser–Fleischer ring and laboratory parameters of copper metabolism. Electrocardiography of the patient incidentally revealed 2nd degree Mobitz type-1 atrioventricular block explaining her episodes of light-headedness. She was started on penicillamine and trihexyphenidyl. The heart block improved spontaneously. Cardiac autonomic function tests including blood pressure response to standing and heart rate response to standing were observed to be normal. We review the literature on cardiac manifestations of Wilson's disease and emphasize that patients with Wilson's disease should be assessed for cardiac arrhythmia and cardiac dysfunction as these may have therapeutic and prognostic implications.

  20. Microgravity alters respiratory sinus arrhythmia and short-term heart rate variability in humans

    Science.gov (United States)

    Migeotte, P-F; Prisk, G. Kim; Paiva, M.; West, J. B. (Principal Investigator)

    2003-01-01

    We studied heart rate (HR), heart rate variability (HRV), and respiratory sinus arrhythmia (RSA) in four male subjects before, during, and after 16 days of spaceflight. The electrocardiogram and respiration were recorded during two periods of 4 min controlled breathing at 7.5 and 15 breaths/min in standing and supine postures on the ground and in microgravity. Low (LF)- and high (HF)-frequency components of the short-term HRV (< or =3 min) were computed through Fourier spectral analysis of the R-R intervals. Early in microgravity, HR was decreased compared with both standing and supine positions and had returned to the supine value by the end of the flight. In microgravity, overall variability, the LF-to-HF ratio, and RSA amplitude and phase were similar to preflight supine values. Immediately postflight, HR increased by approximately 15% and remained elevated 15 days after landing. LF/HF was increased, suggesting an increased sympathetic control of HR standing. The overall variability and RSA amplitude in supine decreased postflight, suggesting that vagal tone decreased, which coupled with the decrease in RSA phase shift suggests that this was the result of an adaptation of autonomic control of HR to microgravity. In addition, these alterations persisted for at least 15 days after return to normal gravity (1G).

  1. Respiratory sinus arrhythmia: opposite effects on systolic and mean arterial pressure in supine humans

    Science.gov (United States)

    Elstad, M.; Toska, K.; Chon, K. H.; Raeder, E. A.; Cohen, R. J.

    2001-01-01

    1. Are arterial blood pressure fluctuations buffered or reinforced by respiratory sinus arrhythmia (RSA)? There is still considerable debate about this simple question. Different results have been obtained, triggering a discussion as to whether or not the baroreflexes are responsible for RSA. We suspected that the measurements of different aspects of arterial pressure (mean arterial pressure (MAP) and systolic pressure (SP)) can explain the conflicting results. 2. Simultaneous recordings of beat-to-beat MAP, SP, left cardiac stroke volume (SV, pulsed ultrasound Doppler), heart rate (HR) and respiration (RE) were obtained in 10 healthy young adults during spontaneous respiration. In order to eliminate HR variations at respiratory frequency we used propranolol and atropine administration in the supine and tilted positions. Respiration-synchronous variation in the recorded variables was quantified by spectral analysis of the recordings of each of these variables, and the phase relations between them were determined by cross-spectral analysis. 3. MAP fluctuations increased after removing heart rate variations in both supine and tilted position, whereas SP fluctuations decreased in the supine position and increased in the head-up tilted position. 4. RSA buffers respiration-synchronous fluctuations in MAP in both positions. However, fluctuations in SP were reinforced by RSA in the supine and buffered in the tilted position.

  2. Anti-Ro/SSA antibodies and cardiac arrhythmias in the adult: facts and hypotheses.

    Science.gov (United States)

    Lazzerini, P E; Capecchi, P L; Laghi-Pasini, F

    2010-09-01

    It is well established that the passive trans-placental passage of anti-Ro/SSA antibodies from mother to foetus is associated with the risk to develop an uncommon syndrome named neonatal lupus (NLE), where the congenital heart block represents the most severe clinical feature. Recent evidence demonstrated that also adult heart, classically considered invulnerable to the anti-Ro/SSA antibodies, may represent a target of the arrhythmogenicity of these autoantibodies. In particular, the prolongation of the QTc interval appears the most frequent abnormality observed in adults with circulating anti-Ro/SSA antibodies, with some data suggesting an association with an increased risk of ventricular arrhythmias, also life threatening. Moreover, even though the association between anti-Ro/SSA antibodies and conduction disturbances is undoubtedly less evident in adults than in infants, from the accurate dissection of the literature data the possibility arises that sometimes also the adult cardiac conduction tissue may be affected by such antibodies. The exact arrhythmogenic mechanisms involved in foetus/newborns and adults, respectively, have not been completely clarified as yet. However, increasing evidence suggests that anti-Ro/SSA antibodies may trigger rhythm disturbances through an inhibiting cross-reaction with several cardiac ionic channels, particularly the calcium channels (L-type and T-type), but also the potassium channel hERG, whose different expression and involvement in the cardiac electrophysiology during lifespan might account for the occurrence of age-related differences.

  3. Respiratory sinus arrhythmia reactivity to a sad film predicts depression symptom improvement and symptomatic trajectory.

    Science.gov (United States)

    Panaite, Vanessa; Hindash, Alexandra Cowden; Bylsma, Lauren M; Small, Brent J; Salomon, Kristen; Rottenberg, Jonathan

    2016-01-01

    Respiratory sinus arrhythmia (RSA) reactivity, an index of cardiac vagal tone, has been linked to self-regulation and the severity and course of depression (Rottenberg, 2007). Although initial data supports the proposition that RSA withdrawal during a sad film is a specific predictor of depression course (Fraguas, 2007; Rottenberg, 2005), the robustness and specificity of this finding are unclear. To provide a stronger test, RSA reactivity to three emotion films (happy, sad, fear) and to a more robust stressor, a speech task, were examined in currently depressed individuals (n=37), who were assessed for their degree of symptomatic improvement over 30weeks. Robust RSA reactivity to the sad film uniquely predicted overall symptom improvement over 30weeks. RSA reactivity to both sad and stressful stimuli predicted the speed and maintenance of symptomatic improvement. The current analyses provide the most robust support to date that RSA withdrawal to sad stimuli (but not stressful) has specificity in predicting the overall symptomatic improvement. In contrast, RSA reactivity to negative stimuli (both sad and stressful) predicted the trajectory of depression course. Patients' engagement with sad stimuli may be an important sign to attend to in therapeutic settings. PMID:26681648

  4. Remote Magnetic Navigation: A Focus on Catheter Ablation of Ventricular Arrhythmias.

    Science.gov (United States)

    Aagaard, Philip; Natale, Andrea; Briceno, David; Nakagawa, Hiroshi; Mohanty, Sanghamitra; Gianni, Carola; Burkhardt, J David; DI Biase, Luigi

    2016-03-01

    VT ablation is based on percutaneous catheter insertion under fluoroscopic guidance to selectively destroy (i.e., ablate) myocardial tissue regions responsible for the initiation or propagation of ventricular arrhythmias. Although the last decade has witnessed a rapid evolution of ablation equipment and techniques, the control over catheter movement during manual ablation has remained largely unchanged. Moreover, the procedures are long, and require ergonomically unfavorable positions, which can lead to operator fatigue. In an attempt to overcome these constraints, several technical advancements, including remote magnetic navigation (RMN), have been developed. RMN utilizes a magnetic field to remotely manipulate specially designed soft-tip ablation catheters anywhere in the x, y, or z plane inside the patient's chest. RMN also facilitates titration of the contact force between the catheter and the myocardial tissue, which may reduce the risk of complications while ensuring adequate lesion formation. There are several non-randomized studies showing that RMN has similar efficacy to manual ablation, while complication rates and total radiation exposure appears to be lower. Although these data are promising, larger randomized studies are needed to prove that RMN is superior to manual ablation of VT.

  5. Genetically engineered SCN5A mutant pig hearts exhibit conduction defects and arrhythmias.

    Science.gov (United States)

    Park, David S; Cerrone, Marina; Morley, Gregory; Vasquez, Carolina; Fowler, Steven; Liu, Nian; Bernstein, Scott A; Liu, Fang-Yu; Zhang, Jie; Rogers, Christopher S; Priori, Silvia G; Chinitz, Larry A; Fishman, Glenn I

    2015-01-01

    SCN5A encodes the α subunit of the major cardiac sodium channel Na(V)1.5. Mutations in SCN5A are associated with conduction disease and ventricular fibrillation (VF); however, the mechanisms that link loss of sodium channel function to arrhythmic instability remain unresolved. Here, we generated a large-animal model of a human cardiac sodium channelopathy in pigs, which have cardiac structure and function similar to humans, to better define the arrhythmic substrate. We introduced a nonsense mutation originally identified in a child with Brugada syndrome into the orthologous position (E558X) in the pig SCN5A gene. SCN5A(E558X/+) pigs exhibited conduction abnormalities in the absence of cardiac structural defects. Sudden cardiac death was not observed in young pigs; however, Langendorff-perfused SCN5A(E558X/+) hearts had an increased propensity for pacing-induced or spontaneous VF initiated by short-coupled ventricular premature beats. Optical mapping during VF showed that activity often began as an organized focal source or broad wavefront on the right ventricular (RV) free wall. Together, the results from this study demonstrate that the SCN5A(E558X/+) pig model accurately phenocopies many aspects of human cardiac sodium channelopathy, including conduction slowing and increased susceptibility to ventricular arrhythmias.

  6. Cardiac Arrhythmias Classification Method Based on MUSIC, Morphological Descriptors, and Neural Network

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available An electrocardiogram (ECG beat classification scheme based on multiple signal classification (MUSIC algorithm, morphological descriptors, and neural networks is proposed for discriminating nine ECG beat types. These are normal, fusion of ventricular and normal, fusion of paced and normal, left bundle branch block, right bundle branch block, premature ventricular concentration, atrial premature contraction, paced beat, and ventricular flutter. ECG signal samples from MIT-BIH arrhythmia database are used to evaluate the scheme. MUSIC algorithm is used to calculate pseudospectrum of ECG signals. The low-frequency samples are picked to have the most valuable heartbeat information. These samples along with two morphological descriptors, which deliver the characteristics and features of all parts of the heart, form an input feature vector. This vector is used for the initial training of a classifier neural network. The neural network is designed to have nine sample outputs which constitute the nine beat types. Two neural network schemes, namely multilayered perceptron (MLP neural network and a probabilistic neural network (PNN, are employed. The experimental results achieved a promising accuracy of 99.03% for classifying the beat types using MLP neural network. In addition, our scheme recognizes NORMAL class with 100% accuracy and never misclassifies any other classes as NORMAL.

  7. Cardiac Arrhythmias Classification Method Based on MUSIC, Morphological Descriptors, and Neural Network

    Science.gov (United States)

    Naghsh-Nilchi, Ahmad R.; Kadkhodamohammadi, A. Rahim

    2009-12-01

    An electrocardiogram (ECG) beat classification scheme based on multiple signal classification (MUSIC) algorithm, morphological descriptors, and neural networks is proposed for discriminating nine ECG beat types. These are normal, fusion of ventricular and normal, fusion of paced and normal, left bundle branch block, right bundle branch block, premature ventricular concentration, atrial premature contraction, paced beat, and ventricular flutter. ECG signal samples from MIT-BIH arrhythmia database are used to evaluate the scheme. MUSIC algorithm is used to calculate pseudospectrum of ECG signals. The low-frequency samples are picked to have the most valuable heartbeat information. These samples along with two morphological descriptors, which deliver the characteristics and features of all parts of the heart, form an input feature vector. This vector is used for the initial training of a classifier neural network. The neural network is designed to have nine sample outputs which constitute the nine beat types. Two neural network schemes, namely multilayered perceptron (MLP) neural network and a probabilistic neural network (PNN), are employed. The experimental results achieved a promising accuracy of 99.03% for classifying the beat types using MLP neural network. In addition, our scheme recognizes NORMAL class with 100% accuracy and never misclassifies any other classes as NORMAL.

  8. The role of Purkinje-myocardial coupling during ventricular arrhythmia: a modeling study.

    Directory of Open Access Journals (Sweden)

    Elham Behradfar

    Full Text Available The Purkinje system is the fast conduction network of the heart which couples to the myocardium at discrete sites called Purkinje-Myocyte Junctions (PMJs. However, the distribution and number of PMJs remains elusive, as does whether a particular PMJ is functional. We hypothesized that the Purkinje system plays a role during reentry and that the number of functional PMJs affect reentry dynamics. We used a computer finite element model of rabbit ventricles in which we varied the number of PMJs. Sustained, complex reentry was induced by applying an electric shock and the role of the Purkinje system in maintaining the arrhythmia was assessed by analyzing phase singularities, frequency of activation, and bidirectional propagation at PMJs. For larger junctional resistances, increasing PMJ density increased the mean firing rate in the Purkinje system, the percentage of successful retrograde conduction at PMJs, and the incidence of wave break on the epicardium. However, the mean firing of the ventricles was not affected. Furthermore, increasing PMJ density above 13/[Formula: see text] did not alter reentry dynamics. For lower junctional resistances, the trend was not as clear. We conclude that Purkinje system topology affects reentry dynamics and conditions which alter PMJ density can alter reentry dynamics.

  9. Complexity-Measure-Based Sequential Hypothesis Testing for Real-Time Detection of Lethal Cardiac Arrhythmias

    Directory of Open Access Journals (Sweden)

    Chen Szi-Wen

    2007-01-01

    Full Text Available A novel approach that employs a complexity-based sequential hypothesis testing (SHT technique for real-time detection of ventricular fibrillation (VF and ventricular tachycardia (VT is presented. A dataset consisting of a number of VF and VT electrocardiogram (ECG recordings drawn from the MIT-BIH database was adopted for such an analysis. It was split into two smaller datasets for algorithm training and testing, respectively. Each ECG recording was measured in a 10-second interval. For each recording, a number of overlapping windowed ECG data segments were obtained by shifting a 5-second window by a step of 1 second. During the windowing process, the complexity measure (CM value was calculated for each windowed segment and the task of pattern recognition was then sequentially performed by the SHT procedure. A preliminary test conducted using the database produced optimal overall predictive accuracy of . The algorithm was also implemented on a commercial embedded DSP controller, permitting a hardware realization of real-time ventricular arrhythmia detection.

  10. Respiratory sinus arrhythmia, effortful control, and parenting as predictors of children's sympathy across early childhood.

    Science.gov (United States)

    Taylor, Zoe E; Eisenberg, Nancy; Spinrad, Tracy L

    2015-01-01

    The goal of this study was to examine physiological and environmental predictors of children's sympathy (an emotional response consisting of feelings of concern or sorrow for others who are distressed or in need) and whether temperamental effortful control mediated these relations. Specifically, in a study of 192 children (23% Hispanic; 54% male), respiratory sinus arrhythmia (RSA), a measure thought to reflect physiological regulation, and observed authoritative parenting (both at 42 months) were examined as predictors of children's effortful control (at 54 months) and, in turn, children's sympathy (at 72 and 84 months). Measures of both baseline RSA and RSA suppression were examined. In a structural equation model, observed parenting was positively related to children's subsequent sympathy through its positive relation to effortful control. Furthermore, the indirect path from baseline RSA to higher sympathy through effortful control was marginally significant. Authoritative parenting and baseline RSA uniquely predicted individual differences in children's effortful control. Findings highlight the potential role of both authoritative parenting and physiological regulation in the development of children's sympathy. PMID:25329555

  11. Dystrophinopathy presenting with arrhythmia in an asymptomatic 34-year-old man: a case report

    Directory of Open Access Journals (Sweden)

    Wakefield Seth E

    2009-07-01

    Full Text Available Abstract Introduction Important clues in the recognition of individuals with dystrophin gene mutations are illuminated in this case report. In particular, this report seeks to broaden the perspective of early signs and symptoms of a potentially life-limiting genetic disorder. This group of disorders is generally considered to be a pediatric muscular dystrophy when in actual fact, this case report may represent a spectrum of subclinically affected adults. Case presentation We present the diagnostic saga of a 34-year-old Caucasian man who had two liver biopsies for elevated liver enzymes and 16 years later presented with a cardiac arrhythmia amidst an emergent appendectomy which finally led to his specific genetic diagnosis. Conclusions This genetic disorder can affect more than one organ, and in our patient affected both skeletal and cardiac muscle. Furthermore, liver function tests when elevated may erroneously implicate a liver disorder when they actually reflect cardiac and skeletal muscle origin. Presented here is a patient with Becker's muscular dystrophy and cardiomyopathy.

  12. The effects of respiratory sinus arrhythmia on anger reactivity and persistence in major depression.

    Science.gov (United States)

    Ellis, Alissa J; Shumake, Jason; Beevers, Christopher G

    2016-10-01

    The experience of anger during a depressive episode has recently been identified as a poor prognostic indicator of illness course. Given the clinical implications of anger in major depressive disorder (MDD), understanding the mechanisms involved in anger reactivity and persistence is critical for improved intervention. Biological processes involved in emotion regulation during stress, such as respiratory sinus arrhythmia (RSA), may play a role in maintaining negative moods. Clinically depressed (MDD; n = 49) and nondepressed (non-MDD; n = 50) individuals were challenged with a stressful computer task shown to increase anger, while RSA (high frequency range 0.15-0.4 Hz) was collected. RSA predicted future anger, but was unrelated to current anger. That is, across participants, low baseline RSA predicted anger reactivity during the task, and in depressed individuals, those with low RSA during the task had a greater likelihood of anger persistence during a recovery period. These results suggest that low RSA may be a psychophysiological process involved in anger regulation in depression. Low RSA may contribute to sustained illness course by diminishing the repair of angry moods. PMID:27401801

  13. Respiratory sinus arrhythmia during worry forecasts stress-related increases in psychological distress.

    Science.gov (United States)

    Gouin, Jean-Philippe; Deschênes, Sonya S; Dugas, Michel J

    2014-09-01

    Respiratory sinus arrhythmia (RSA) has been conceptualized as an index of emotion regulation abilities. Although resting RSA has been associated with both concurrent and prospective affective responses to stress, the impact of RSA reactivity on emotional responses to stress is inconsistent across studies. The type of emotional stimuli used to elicit these phasic RSA responses may influence the adaptive value of RSA reactivity. We propose that RSA reactivity to a personally relevant worry-based stressor might forecast future affective responses to stress. To evaluate whether resting RSA and RSA reactivity to worry inductions predict stress-related increases in psychological distress, an academic stress model was used to prospectively examine changes in psychological distress from the well-defined low- and high-stress periods. During the low-stress period, 76 participants completed self-report mood measures and had their RSA assessed during a resting baseline, free worry period and worry catastrophizing interview. Participants completed another mood assessment during the high-stress period. Results indicated that baseline psychological distress predicted larger decreases in RSA during the worry inductions. Lower resting RSA and greater RSA suppression to the worry inductions at baseline prospectively predicted larger increases in psychological distress from the low- to high-stress period, even after accounting for the impact of baseline distress on RSA. These results provide further evidence that RSA may represent a unique index of emotion regulation abilities in times of stress. PMID:25089936

  14. Complexity-Measure-Based Sequential Hypothesis Testing for Real-Time Detection of Lethal Cardiac Arrhythmias

    Science.gov (United States)

    Chen, Szi-Wen

    2006-12-01

    A novel approach that employs a complexity-based sequential hypothesis testing (SHT) technique for real-time detection of ventricular fibrillation (VF) and ventricular tachycardia (VT) is presented. A dataset consisting of a number of VF and VT electrocardiogram (ECG) recordings drawn from the MIT-BIH database was adopted for such an analysis. It was split into two smaller datasets for algorithm training and testing, respectively. Each ECG recording was measured in a 10-second interval. For each recording, a number of overlapping windowed ECG data segments were obtained by shifting a 5-second window by a step of 1 second. During the windowing process, the complexity measure (CM) value was calculated for each windowed segment and the task of pattern recognition was then sequentially performed by the SHT procedure. A preliminary test conducted using the database produced optimal overall predictive accuracy of[InlineEquation not available: see fulltext.]. The algorithm was also implemented on a commercial embedded DSP controller, permitting a hardware realization of real-time ventricular arrhythmia detection.

  15. Complexity-Measure-Based Sequential Hypothesis Testing for Real-Time Detection of Lethal Cardiac Arrhythmias

    Directory of Open Access Journals (Sweden)

    Szi-Wen Chen

    2007-01-01

    Full Text Available A novel approach that employs a complexity-based sequential hypothesis testing (SHT technique for real-time detection of ventricular fibrillation (VF and ventricular tachycardia (VT is presented. A dataset consisting of a number of VF and VT electrocardiogram (ECG recordings drawn from the MIT-BIH database was adopted for such an analysis. It was split into two smaller datasets for algorithm training and testing, respectively. Each ECG recording was measured in a 10-second interval. For each recording, a number of overlapping windowed ECG data segments were obtained by shifting a 5-second window by a step of 1 second. During the windowing process, the complexity measure (CM value was calculated for each windowed segment and the task of pattern recognition was then sequentially performed by the SHT procedure. A preliminary test conducted using the database produced optimal overall predictive accuracy of 96.67%. The algorithm was also implemented on a commercial embedded DSP controller, permitting a hardware realization of real-time ventricular arrhythmia detection.

  16. QUANTIFICATION OF RESPIRATORY SINUS ARRHYTHMIA WITH HIGH-FRAMERATE ELECTRICAL IMPEDANCE TOMOGRAPHY

    Directory of Open Access Journals (Sweden)

    Christoph Hoog Antink

    2013-12-01

    Full Text Available Respiratory Sinus Arrhythmia, the variation in the heart rate synchronized with the breathing cycle, forms an interconnection between cardiac-related and respiratory-related signals. It can be used by itself for diagnostic purposes, or by exploiting the redundancies it creates, for example by extracting respiratory rate from an electrocardiogram (ECG. To perform quantitative analysis and patient specific modeling, however, simultaneous information about ventilation as well as cardiac activity needs to be recorded and analyzed. The recent advent of medically approved Electrical Impedance Tomography (EIT devices capable of recording up to 50 frames per second facilitates the application of this technology. This paper presents the automated selection of a cardiac-related signal from EIT data and quantitative analysis of this signal. It is demonstrated that beat-to-beat intervals can be extracted with a median absolute error below 20 ms. A comparison between ECG and EIT data shows a variation in peak delay time that requires further analysis. Finally, the known coupling of heart rate variability and tidal volume can be shown and quantified using global impedance as a surrogate for tidal volume.

  17. Point process time-frequency analysis of respiratory sinus arrhythmia under altered respiration dynamics.

    Science.gov (United States)

    Kodituwakku, Sandun; Lazar, Sara W; Indic, Premananda; Brown, Emery N; Barbieri, Riccardo

    2010-01-01

    Respiratory sinus arrhythmia (RSA) is largely mediated by the autonomic nervous system through its modulating influence on the heartbeat. We propose an algorithm for quantifying instantaneous RSA as applied to heart beat interval and respiratory recordings under dynamic respiration conditions. The blood volume pressure derived heart beat series (pulse intervals, PI) are modeled as an inverse gaussian point process, with the instantaneous mean PI modeled as a bivariate regression incorporating both past PI and respiration values observed at the beats. A point process maximum likelihood algorithm is used to estimate the model parameters, and instantaneous RSA is estimated by a frequency domain transfer function approach. The model is statistically validated using Kolmogorov-Smirnov (KS) goodness-of-fit analysis, as well as independence tests. The algorithm is applied to subjects engaged in meditative practice, with distinctive dynamics in the respiration patterns elicited as a result. Experimental results confirm the ability of the algorithm to track important changes in cardiorespiratory interactions elicited during meditation, otherwise not evidenced in control resting states.

  18. Arrhythmia detection in single- and dual-chamber implantable cardioverter defibrillators: the more leads, the better?

    Science.gov (United States)

    Francia, Pietro; Balla, Cristina; Uccellini, Arianna; Cappato, Riccardo

    2009-09-01

    The implantable cardioverter defibrillator (ICD) offers life-saving therapies for primary and secondary prevention of sudden cardiac death in high-risk patients. However, ICD detection algorithms consistently misclassify a substantial proportion of supraventricular rhythms, thus carrying the risk for inappropriate therapies. Although single-chamber ICD (Sc-ICD) discrimination tools have been reported to provide high specificity in rejecting sinus tachycardia and atrial fibrillation with a relatively low ventricular rate, accurate recognition of atrial fibrillation with faster ventricular rates, atrial tachycardias, atrial flutter, and some reentrant tachycardias is still an issue. Dual-chamber ICDs (Dc-ICDs) are supposed to overcome specificity issues by enhancing detection algorithms with information derived from the atrial and ventricular timing relationship. The initial promise of Dc-ICDs was to improve detection specificity without compromising sensitivity, and to translate this advantage over Sc-ICDs in a more selective use of aggressive therapies. Despite this solid background, superiority of Dc- over Sc-ICDs has never been convincingly demonstrated. The present review focuses on the efficacy of contemporary ICD arrhythmia discrimination tools and appraises the so far reported evidence supporting the superiority of Dc-ICDs in preventing inappropriate therapies.

  19. Mobile telemonitoring for arrhythmias in outpatients in the Republic of Georgia: a brief report of a pilot study.

    Science.gov (United States)

    Kirtava, Zviad; Gegenava, Thea; Gegenava, Maka; Matoshvili, Zviad; Kasradze, Sofia; Kasradze, Pavle

    2012-09-01

    As the very first trial of mobile telemedicine in the Republic of Georgia, in June-December 2010 we investigated 35 outpatients with different types of arrhythmia (male/female ratio=16/19; 12-80 years old), among them 5 patients with concomitant epilepsy. The control group comprised 7 clinically healthy sportsmen (soccer players, all men; 15-17 years old), during a 30-min velo ergometer stress test. A three-lead electrocardiogram (ECG) loop recorder (Vitaphone BT 3300; Vitasystems GmbH, Mannheim, Germany) was used in automatic mode, using special LRMA software (MDT, Lázně Bohdaneč, Czech Republic) and a Nokia (Espoo, Finland) model 6730 Symbian phone. Automatically recorded arrhythmia events were transmitted from the loop recorder by Bluetooth(®) (Bluetooth SIG, Inc., Kirkland, WA) to a phone and then by 3G (through our partner mobile operator, MagtiCom Ltd. [Tbilsi, Georgia]) to the Vitasystems server in Germany and were available to Georgian physicians via e-mail/Internet. Arrhythmias were recorded/monitored during 7-68 h of observation. The number of automatically recorded ECG events varied between 3 and 170 per observation, or 0.4-10.7 hourly. Cases of sinus brady- and tachyarrhythmia, sinus node weakness syndrome, atrial fibrillation, supraventricular tachycardia, supraventricular premature complexes, and ventricular premature complexes were correctly recognized by automatic recognition software and recorded. In 3 patients and 1 sportsman previously unspecified (despite multiple investigations), arrhythmias were recorded: paroxysmal tachycardia (n=1), sinus node weakness syndrome (n=1), and ventricular premature complexes (n=2). In 3 cases (all women) light insomnia and nervousness were reported. In 2 patients with neurosis (both elderly men, 1 with epilepsy) we had to stop investigation prematurely because of anxiety/agitation. Mobile telecardiology represents feasible methodology to monitor arrhythmias in outpatients in Georgia, promoting earlier

  20. Ventricular arrhythmias in competitive athletes: risk stratification with T-wave alternans

    Directory of Open Access Journals (Sweden)

    Rita Pizzi

    2009-08-01

    Full Text Available Introduction: Aim of our study is to evaluate the role of TWA to stratify the risk of sudden cardiac death in athletes (Ath with complex ventricular arrhythmias (VA, and to document a possible correlation between TWA and electrophysiological testing (EES results. Methods: We studied 43 Ath with VA (31 M, mean age 34 ± 12 years. In all cases a cardiological evaluation was performed, including TWA and EES. The patients were evaluated during a followup of 25 ± 22 months. The end-point was the occurrence of sudden death or malignant ventricular tachyarrhythmias (VT. Results: TWA was negative in 28 Ath (65%, positive in 8 (19% and indeterminate in 7 (16%. All subjects with negative TWA did not show induction of VT at EES, with significant correlation between negative TWA and negative EES (p<0.001. All Ath with positive TWA also had VT induced by a EES, but without significant correlation between positive TWA and positive EES. In 2 Ath with undetermined TWA (29% VT were induced at EES. Our data did not show significant correlation between indeterminate TWA and positive or negative EES. However, logistic regression analysis showed significant correlation between abnormal TWA test (positive or indeterminate and inducibility of VT at EES (p<0.001. During follow-up we observed a significant difference in end-point occurrence between Ath with negative or positive TWA and between Ath with negative or positive EES. Conclusion: TWA confirm its role as a simple and non-invasive test, and it seems useful for prognostic stratification of Ath with VA. (Heart International 2007; 3: 58-67

  1. Prolonged hypoxia increases survival even in Zebrafish (Danio rerio showing cardiac arrhythmia.

    Directory of Open Access Journals (Sweden)

    Renate Kopp

    Full Text Available Tolerance towards hypoxia is highly pronounced in zebrafish. In this study even beneficial effects of hypoxia, specifically enhanced survival of zebrafish larvae, could be demonstrated. This effect was actually more pronounced in breakdance mutants, which phenotypically show cardiac arrhythmia. Breakdance mutants (bre are characterized by chronically reduced cardiac output. Despite an about 50% heart rate reduction, they become adults, but survival rate significantly drops to 40%. Normoxic bre animals demonstrate increased hypoxia inducible factor 1 a (Hif-1α expression, which indicates an activated hypoxic signaling pathway. Consequently, cardiovascular acclimation, like cardiac hypertrophy and increased erythrocyte concentration, occurs. Thus, it was hypothesized, that under hypoxic conditions survival might be even more reduced. When bre mutants were exposed to hypoxic conditions, they surprisingly showed higher survival rates than under normoxic conditions and even reached wildtype values. In hypoxic wildtype zebrafish, survival yet exceeded normoxic control values. To specify physiological acclimation, cardiovascular and metabolic parameters were measured before hypoxia started (3 dpf, when the first differences in survival rate occurred (7 dpf and when survival rate plateaued (15 dpf. Hypoxic animals expectedly demonstrated Hif-1α accumulation and consequently enhanced convective oxygen carrying capacity. Moreover, bre animals showed a significantly enhanced heart rate under hypoxic conditions, which reached normoxic wildtype values. This improvement in convective oxygen transport ensured a sufficient oxygen and nutrient supply and was also reflected in the significantly higher mitochondrial activity. The highly optimized energy metabolism observed in hypoxic zebrafish larvae might be decisive for periods of higher energy demand due to organ development, growth and increased activity. However, hypoxia increased survival only during a

  2. Reduction of complex ventricular arrhythmias after enalapril treatment in patients with advanced stable heart failure.

    Science.gov (United States)

    Pomini, G; Gribaldo, R; Rugna, A; Lupia, M; Molfese, G; Carenza, P

    1991-01-01

    We studied, by 48-hour Holter monitoring, 33 patients with chronic stable heart failure (radionuclide ejection fraction less than 35%), complex ventricular arrhythmias and no electrolyte abnormalities, after a period during which they were treated with digoxin and diuretics. Before Holter monitoring blood samples were analyzed for serum concentration of sodium, potassium, magnesium, urea, creatinine, digoxin, aldosterone and for plasmatic renin activity in addition to urinary aldosterone and catecholamines determination. After these investigations in 23 patients, 5-20 mg of enalapril were progressively added to the conventional therapy, while 10 patients continued the previous therapy. After 8 weeks 30 patients were subjected to a second 48-hour Holter monitoring and to the same biochemical and hormonal tests. One patient died and 2 were lost to follow up. Only the enalapril group showed a significant decrease in the number of premature ventricular complexes (PVC) (p less than 0.01), and the frequency of couplets and episodes of ventricular tachycardia (VT) declined significantly (P less than 0.01). In the two groups there were no significant changes in digoxin, sodium, or magnesium, while potassium concentration increased in both groups (p less than 0.01). In the enalapril group heart rate and systolic and diastolic pressure declined significantly (p less than 0.01), and New York Heart Association class (NYHA) improved (p less than 0.001). In the other group there were no significant changes in these parameters. Enalapril caused a significant increase in the plasmatic renin activity (p less than 0.01) and a significant fall of plasma and urinary aldosterone (p less than 0.01; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2055378

  3. Respiratory sinus arrhythmia as a predictor of self-injurious thoughts and behaviors among adolescents.

    Science.gov (United States)

    Wielgus, Madeline D; Aldrich, Jaclyn T; Mezulis, Amy H; Crowell, Sheila E

    2016-08-01

    Research suggests that self-injurious thoughts and behaviors (SITBs) may function as maladaptive emotion regulation strategies. One psychophysiological index of emotion regulatory capacity is respiratory sinus arrhythmia (RSA). The temporal course of RSA responsivity to a stressor may be characterized by basal RSA, RSA reactivity to stressor, and RSA recovery post-stressor. RSA has been linked to both internalizing and externalizing symptoms in adolescents, but little is known about the relation between RSA and SITBs. Initial research has shown a cross-sectional relation between lower basal RSA and greater RSA reactivity to a sad mood induction and self-injury. To date no prospective research on the relation between RSA and SITBs exists. The current study aims to investigate the prospective relation between RSA and SITBs in a community sample of 108 adolescents (Mage=12.82, SDage=0.82, 53.70% female). At the initial laboratory visit (T1), participants completed an unsolvable anagram stressor task, during which RSA (basal, reactivity, and recovery) was measured. SITBs were assessed at T1 and at the 6-month follow-up (T2). Results indicated basal RSA and RSA reactivity did not significantly predict engagement in SITBs between T1 and T2. Poorer RSA recovery from the stressor task at T1 did significantly predict engagement in SITBs between T1 and T2, over and above depressive symptoms and lifetime history of SITBs. This suggests that adolescents with poor ability to regulate physiologically following a stressor may turn to maladaptive emotion regulation strategies like SITBs. PMID:27212441

  4. Lack of significant effects of superoxide dismutase and catalase on development of reperfusion arrhythmias.

    Science.gov (United States)

    Hagar, J M; Hale, S L; Ilvento, J P; Kloner, R A

    1991-01-01

    It has been reported that agents having the ability to scavenge oxygen-derived free radicals reduce the severity of ventricular arrhythmias that occur after brief coronary occlusion and reperfusion. Superoxide dismutase plus catalase (SOD + CAT) or placebo was administered in a blinded randomized fashion prior to coronary occlusion in rats (n = 25 each group) undergoing a 5-min left coronary occlusion followed by 15 min of reperfusion. During reperfusion, ventricular tachycardia (VT) developed in 96% of animals in both groups. Reperfusion ventricular fibrillation (VF) developed in 60% of the placebo group vs 56% in the SOD + CAT group (p = 1.0). Irreversible VF occurred in 40% of the placebo group vs 20% in the SOD + CAT group (p = 0.22). Atrioventricular block occurred in 12% of placebo and 4% of SOD + CAT animals (p = 0.61). There were no significant difference between groups in duration of VT (85 +/- 15 s (mean +/- SEM) placebo vs 81 +/- 14 s SOD + CAT, p = 0.81), total duration of VT plus VF (391 +/- 76 s placebo vs 256 +/- 64 SOD + CAT, p = 0.45) or numbers of single ventricular ectopic beats (65 +/- 15 placebo vs 97 +/- 18 SOD + CAT, p = 0.18). Heart rate at reperfusion was slightly higher in control than SOD + CAT animals (340 +/- 33 vs 319 +/- 32, p = 0.02). Risk zone size, determined by Monastral blue injection, was equal in both groups (34 +/- 2% of ventricular mass). The occurrence of reperfusion VF in this model could not be predicted by heart rate at reperfusion (331 +/- 33 VF animlas vs 328 +/- 36 no VF, p = 0.77), or by risk zone size (34 +/- 2%, VF and no VF groups).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1877967

  5. Effects of Intrinsic and Extrinsic Cardiac Nerves on Atrial Arrhythmia in Experimental Pulmonary Artery Hypertension.

    Science.gov (United States)

    Zhao, Qingyan; Deng, Hongping; Jiang, Xuejun; Dai, Zixuan; Wang, Xiaozhan; Wang, Xule; Guo, Zongwen; Hu, Wei; Yu, Shengbo; Yang, Bo; Tang, Yanhong; Huang, Congxin

    2015-11-01

    Atrial arrhythmia, which includes atrial fibrillation (AF) and atrial flutter (AFL), is common in patients with pulmonary arterial hypertension (PAH), who often have increased sympathetic nerve activity. Here, we tested the hypothesis that autonomic nerves play important roles in vulnerability to AF/AFL in PAH. The atrial effective refractory period and AF/AFL inducibility at baseline and after anterior right ganglionated plexi ablation were determined during left stellate ganglion stimulation or left renal sympathetic nerve stimulation in beagle dogs with or without PAH. Then, sympathetic nerve, β-adrenergic receptor densities and connexin 43 expression in atrial tissues were assessed. The sum of the window of vulnerability to AF/AFL was increased in the right atrium compared with the left atrium at baseline in the PAH dogs but not in the controls. The atrial effective refractory period dispersion was increased in the control dogs, but not in the PAH dogs, during left stellate ganglion stimulation. The voltage thresholds for inducing AF/AFL during anterior right ganglionated plexi stimulation were lower in the PAH dogs than in the controls. The AF/AFL inducibility was suppressed after ablation of the anterior right ganglionated plexi in the PAH dogs. The PAH dogs had higher sympathetic nerve and β1-adrenergic receptor densities, increased levels of nonphosphorylated connexin 43, and heterogeneous connexin 43 expression in the right atrium when compared with the control dogs. The anterior right ganglionated plexi play important roles in the induction of AF/AFL. AF/AFL induction was associated with right atrium substrate remodeling in dogs with PAH.

  6. Long-term Arrhythmia Monitoring in Cryptogenic Stroke: Who, How, and for How Long?

    Science.gov (United States)

    Montalvo, Mayra; Ali, Rushna; Silver, Brian; Khan, Muhib

    2016-01-01

    Cryptogenic stroke and transient ischemic attack (TIA) account for approximately one-third of stroke patients [1]. Paroxys-mal atrial fibrillation (PAF) has been suggested as a major etiology of these cryptogenic strokes [2, 3]. PAF can be difficult to diagnose because it is intermittent, often brief, and asymptomatic. PAF might be more prevalent than persistent atrial fibrillation in stroke and TIA patients, especially in younger populations [4, 5]. In patients with atrial fibrillation, anticoagulation provides significant risk reduction [6]. A new generation of oral anticoagulants has been approved for non-valvular atrial fibrillation, providing a variety of therapeutic options for patients with atrial fibrillation and risk of stroke [7]. Prior practice included an admission electrocardiogram (ECG) and continuous telemetry monitoring while in hospital [8]. However, this approach can lead to under-detection of brief asymptomatic events, which can occur at variable intervals, often outside of the hospital setting. Technological advancements have led to devices that can monitor cardiac rhythms outside of the hospital for longer durations resulting in higher yield of detection of atrial fibrillation events. Moreover, recent studies show that the normal monitoring time for arrhythmias may be shorter than ideal in order to detect atrial fibrillation, and increasing this interval could significantly improve detection of atrial fibrillation in these patients [9, 10]. The aim of this study is to review the literature in order to define what subgroup of patients, with what methodologies, and for how long monitoring for atrial fibrillation should occur in patients presenting with cryptogenic stroke. PMID:27347225

  7. Improving Managers' Psychophysical Well-Being: Effectiveness of Respiratory Sinus Arrhythmia Biofeedback.

    Science.gov (United States)

    Munafò, Marianna; Patron, Elisabetta; Palomba, Daniela

    2016-06-01

    High work stress has been consistently associated with disturbed autonomic balance, specifically, lowered vagal cardiac control and increased sympathetic activity, which may lead to increased cardiovascular risk. Stress management procedures have been proposed to reduce autonomic dysfunctions related to work stress in different categories of workers exposed to heightened work demands, while a limited number of studies addressed this issue in managers. The present study was aimed at evaluating the effectiveness of a respiratory sinus arrhythmia (RSA) biofeedback (BF) intervention on psychological and physiological outcomes, in managers with high-level work responsibilities. Thirty-one managers leading outstanding private or public companies were randomly assigned to either a RSA-BF training (RSA-BF; N = 16) or a control group (N = 15). The RSA-BF training consisted of five weekly 45 min sessions, designed to increase RSA, whereas controls had to provide a daily stress diary once a week. After the training, managers in both groups reported reduced heart rate at rest, lower anxiety levels and improvement in health-related quality of life. More importantly, managers in the RSA-BF group showed increased vagal control (as indexed by increased RSA), decreased sympathetic arousal (as indexed by reduced skin conductance and systolic blood pressure) and lower emotional interferences, compared to managers in the control group. Results from this study showed that RSA-BF training was effective in improving cardiac autonomic balance at rest. Moreover, findings from this study underline the effectiveness of biofeedback in reducing psychophysiological negative outcomes associated with stress in managers. PMID:26446978

  8. Optimization of helical pitch in cardiac MDCT acquisition in patients with arrhythmia requiring ECG-edit

    International Nuclear Information System (INIS)

    The electrocardiogram (ECG)-edit is necessary in cardiac multidetector-row CT (MDCT) in arrhythmias [premature atrial contraction (PAC) or premature ventricular contraction (PVC)]; however, it sometimes results in a data deficit. Therefore, a thinner helical pitch (HP) should be set to avoid data deficits. The thinner helical pitch creates more radiation exposure. The purpose is to optimize HP in PAC or PVC. In a phantom study, an acrylic phantom (10 x 10 x 500 mm) was scanned by MDCT (Aquilion 64) using an artificial pacemaker at various gantry rotation speeds (r) and HP. We evaluated the relationships between HP and the maximal table moving length (Lmax) in the border of data deficit, and among r, HP, and the maximum data collection time interval (Tmax). In the clinical study, cardiac MDCT was performed in 44 cases (M/F: 26/18, 71.4±10.6 yrs) including 30 PAC and 14 PVC using the optimal HP derived from Tmax+10%. In the phantom study, there were significant correlations between HP and Lmax (Lmax=34.94-0.32 HP, r=0.999, P<0.0001), and Tmax [Tmax=(69.88/HP-0.64) x r] was calculated using formula. In 42/44 patients, high-quality images were obtained using the optimal HP; however, it resulted in data deficits in 2 patients, because of heart rate decreasing and a couple of PAC during scanning. Optimal HP significantly (P<0.0001) reduced radiation dose (-11.4%) compared with conventional HP. In conclusion, the optimal HP in PAC or PVC was calculated from the phantom study, provided fine images in 95% patients, and could reduce radiation dose. (author)

  9. Clinical Analysis of Depressive, Anxiety Arrhythmia in Patients with Sleep and Arrhythmia%伴发抑郁、焦虑的心律失常患者睡眠与心律失常的临床分析

    Institute of Scientific and Technical Information of China (English)

    计秀玲

    2015-01-01

    Objective The effects of sleep on arrhythmia patients with depression and anxiety disorders on arrhythmias are analyzed and discussed briefly.Methods 160 cases of arrhythmia patients and 50 healthy as the control group, depression, the self rating Anxiety Scale and Pittsburgh sleep quality index evaluation. Results The index of HRV time domain indexes anxiety group, depression group, Comorbidity groups in sleep quality factor and total score to sleep is significantly higher than the control group in the total score and the time to fal asleep,In terms of total sleep and sleep time there exists obvious difference being statisticaly significant ,P<0.05.ConclusionArrhythmia patients with depression, anxiety and comorbid anxiety and depression wil decrease obviously in HRV time domain indexes, which also shows the autonomic nervous there may be some adverse effects on the heart adjustment.%目的 对伴抑郁及焦虑情绪障碍的心律失常患者的睡眠情况对心律失常的影响进行简要的分析和探讨.方法 将160例心律失常患者和50个健康将其作为对照组,对其进行抑郁、焦虑自评量表和匹茨堡睡眠质量指数量表进行测评,同时还要对HRV指标进行详细的分析.结果 HRV时域指标方面焦虑组、抑郁组、共病组的指标都要比正常组的值要高.共病组在睡眠质量因子上和睡眠总分方面要明显比对照组高,在睡眠总分和入睡时间等方面两者存在着较为明显的统计学差异,P<0.05.结论 伴抑郁、焦虑和焦虑抑郁共病的心律失常患者在HRV时域指标会出现非常明显的下降,这也说明自主神经对心脏的调节可能存在着一些不利影响.

  10. Effects of Chronic Oral Administration of Natural Honey on Ischemia/Reperfusion-induced Arrhythmias in Isolated Rat Heart

    Directory of Open Access Journals (Sweden)

    Moslem Najafi

    2011-01-01

    Full Text Available Objective(sIn this study, effects of chronic administration of oral natural honey against ischemia/reperfusion (I/R-induced cardiac arrhythmias were investigated in isolated rat heart. Materials and MethodsMale Wistar rats were divided into four groups (n= 10-14 rats in each group and fed with natural honey (1%, 2% and 4% dissolved in the drinking water for 45 days except for the control group. After anesthesia, the rats’ hearts were isolated quickly, mounted on a Langendorff apparatus and perfused with a modified Krebs-Henseleit solution during stabilization, 30 min regional ischemia followed by 30 min reperfusion. The ECGs were recorded throughout the experiments to analyze cardiac arrhythmias based on the Lambeth conventions. ResultsIn the ischemic phase, honey (1% significantly reduced (P<0.05 the number and duration of ventricular tachycardia (VT. Honey (1% and 2% also significantly decreased number of ventricular ectopic beats (VEBs. In addition, incidence and duration of reversible ventricular fibrillation (Rev VF were lowered by honey 2% (P<0.05. During reperfusion time, VT incidence was 73% in the control group, however natural honey (1% decreased it to 22% (P<0.05. Honey also produced significant reduction in the incidences of total VF, Rev VF, duration and number of VT. ConclusionFor the first time, the results of present study demonstrated protective effects of chronic oral honey administration against I/R-induced arrhythmias in isolated rat heart. Antioxidant activity, the existence of energy sources such as glucose and fructose and improvement of some hemodynamic functions might be responsible for these effects.

  11. The effects of verapamil, prenylamine, flunarizine and cinnarizine on coronary artery occlusion-induced arrhythmias in anaesthetized rats.

    Science.gov (United States)

    Fagbemi, O.; Kane, K. A.; McDonald, F. M.; Parratt, J. R.; Rothaul, A. L.

    1984-01-01

    In male rats, anaesthetized with pentobarbitone, ligation of the main left coronary artery causes an early phase of ventricular arrhythmias which last about 30 min. In approximately 60% of control animals, ventricular fibrillation occurs but since spontaneous reversion to sinus rhythm may occur, mortality is of the order of 30%. When administered intravenously 15 min prior to ligation, verapamil (0.01 and 0.05 mg kg-1), prenylamine (0.5 mg kg-1), flunarizine (0.1, 0.25, 0.5 and 1.0 mg kg-1) and cinnarizine (0.25, 0.5 and 1.0 mg kg-1) protected against these arrhythmias. Higher doses of verapamil (0.1 and 0.5 mg kg-1), prenylamine (5 mg kg-1) and flunarizine (2.5 mg kg-1) did not afford a similar protection and mortality was increased to or above control values. Death was due in prenylamine-treated rats to atrioventricular block leading to asystole whereas in those administered verapamil or flunarizine it was a consequence of persistent ventricular fibrillation. Prior to ligation, a sustained fall in mean arterial blood pressure was observed only following the administration of the highest doses of prenylamine, flunarizine and cinnarizine. Heart rate was reduced by administration of only the highest dose of prenylamine. These studies show that although the four calcium antagonists studied, i.e. verapamil, prenylamine, flunarizine and cinnarizine do suppress ischaemia-induced arrhythmias, this protective effect may be limited to a narrow concentration range. PMID:6487894

  12. The Effects of Hesperidin on Ischemia/Reperfusion Induced Arrhythmias and Infarct Size in Isolated Rat Heart

    Directory of Open Access Journals (Sweden)

    Mahdieh Pashai, Seyedeh Negisa Seyed Toutounchi, Maryam Rameshrad, Haleh Vaez, Fatemeh Fathiazad, Alireza Garjani

    2016-06-01

    Full Text Available Background: Hesperidin is a flavonoid and has strong anti-oxidant and anti-inflammatory activities. The aim of the present study is to investigate the effects of hesperidin on ischemic/reperfusion (I/R induced injuries and arrhythmias. Methods: Male Wistar rats were anesthetized and then the hearts were removed and cannulated immediately to a langendorff apparatus and prepared for the left coronary artery ligation. The hearts were perfused with Krebs-Henseleit Buffer Solution (KHBS; control or KHBS plus hesperidin (1, 2.5 & 5µg/ml; treated groups 5 minutes before coronary occlusion, during the ischemia, and reperfusion period. After reperfusion, double staining strategy (Evans blue and TTC were used. The percentage of infarct size was determined by Image-j software. Arrhythmia in control group and treated groups were analyzed and compared. Lactate concentration was measured in samples at the end of stabilization, 30 minute after ischemia, and 60 minute after reperfusion. Western blotting was performed for evaluation of pAMPK at the end of the ischemia in the heart tissues. Results: The results demonstrated that hesperidin caused a significant reduction in ventricular ectopic beats (VEBs number during ischemia and reperfusion phase (p<0.01, p<0.05. The infarct size was reduced significantly by all concentration of hesperidin (p<0.001 and Lactate concentration at the end of ischemia had a significant reduction in the treatment groups (p<0.001. pAMPK/AMPK ratio was reduced by hesperidin at 5 µg/ml. Conclusion: The results of the study suggest that hesperidin has protective effects against I/R induced injuries and arrhythmias in isolated rat hearts that could be related to its effect on modulating of AMPK activity.

  13. Analysis of Arrhythmia Caused by Diabetic Hypoglycemia%糖尿病低血糖诱发室性心律失常14例分析

    Institute of Scientific and Technical Information of China (English)

    陈聪

    2013-01-01

    目的::探讨糖尿病低血糖诱发室性心律失常作用机制及应对方法。方法:回顾性分析40例糖尿病低血糖病例在治疗前后的心律变化。结果:糖尿病低血糖有诱发室性心律失常作用。结论:糖尿病低血糖病例伴有室性心律失常时,应疑及由低血糖诱发可能性,同时糖尿病低血糖诱发的室性心律失常,只要抢救及时,大多数具有可逆性,并且预后良好。%Objective:To investigate the relationship between diabetic hypoglycemia and arrhythmia and the dealing methods.Method:Retrospectively studied 40 cases of diabetes hypoglycemia and the process before and after treatment.Result:Diabetic hypoglycemia could cause arrhythmia.Conclusion:If hypoglycemia arises with arrhythmia,it is possible that arrhythmia is caused by Hypoglycemia.Meanwhile many cases with arrhythmia caused by diabetic hypoglycemia may be reversible if saved in time.

  14. Design and implementation of an electrocardiographical signal acquisition and digital processing system orientated to the detection of paroxysmal arrhythmias

    Science.gov (United States)

    Iriart Braceli, Agustín; Exequiel Morani, Jorge

    2011-12-01

    This article describes the design, technical aspects and implementation of a device capable of acquiring electrocardiograph signals; visualize them in real time over a graphic liquid crystal display (GLCD), and the storage of these ECG registers on a SD memory card. It also details a noise suppression algorithm using the Wavelet Transform. This system was specially developed to cover some bankruptcy that presents actual Holters or ECG regarding the detection of paroxysmal arrhythmias. The contribution of this work is settled on its portability and low production cost. The filtering method used provides an ECG signal without any significant noise and appropriate to the diagnosis of cardiac pathologies.

  15. Correlation between 24-hour profile of blood pressure and ventricular arrhythmias and their prognostic significance in patients with arterial hypertension

    Directory of Open Access Journals (Sweden)

    Đorđević Dragan

    2008-01-01

    Full Text Available Background/Aim. Left ventricular hypertrophy (LVH, apart from arterial hypertension, is a risk factor for electrophysiologic heart condition disorder and sudden cardiac death. The aim of this study was to examine a relationship between complex ventricular arrhythmias and parameters of 24-hour ambulatory blood pressure monitoring in the patients with arterial hypertension and left ventricular hypertrophy (LVH, as well as their prognostic significance during a five-year follow-up. Methods. Ninety patients with arterial hypertension and LVH were included in this study (mean age 55.2±8.3 years. There were 35 healthy people in the control group (mean age 54.5±7.1 years. Left ventricular mass index was 171.9±32.4 g/m2 in the LVH group and 102.4±13.3 g/m2 in the control group. Clinical examination, echocardiogram, 24-hour ambulatory blood pressure monitoring and 24-hour holter monitoring were done in all of the examined persons. Ventricular arrhythmias were classified by the Lown classification. Results. In the LVH group there were 54 (60.0% of the patients with ≥ III Lown class. The best predictor of a Lown class were left ventricular mass index by using multivariate stepwise regression analyses (β = 0.212; p < 0.05 and small decrease of diastolic blood pressure during the night (β = -0.293; p < 0.01. The main predictor of bad prognosis was left ventricular mass index during a five year follow-up (β = 0.302; p < 0.01, for stepwise regression model: F = 8.828; p < 0.01, adjusted R2 = 0.091. Conclusion. Left ventricular arrhythmias are frequent in patients with lower decrease of blood pressure during the night. There was no correlation between the degree of ventricular arrhythmias and parameters from 24-hour blood pressure monitoring and a five-year prognosis in the patients with arterial hypertension and LVH. A bad five-year follow-up outcome of hypertensive disease depends on left ventricular mass index.

  16. Ventricular arrhythmias and risk of death and acute myocardial infarction in apparently healthy subjects of age >or=55 years

    DEFF Research Database (Denmark)

    Sajadieh, A; Nielsen, OW; Rasmussen, Verner;

    2006-01-01

    , and 48-hour ambulatory electrocardiographic monitoring. All patients were followed for up to 5 years. Combined events were defined as all-cause mortality or acute myocardial infarction. A cardiovascular event was defined as cardiovascular death or acute myocardial infarction. In total, 84% had 0 to 10...... arrhythmias were studied in a cohort of middle-aged and elderly subjects without apparent heart disease. Six hundred seventy-eight men and women aged 55 to 75 years without a history of heart disease or stroke were included. Baseline examinations included physical examinations, fasting laboratory testing...

  17. Mobile Telemonitoring for Arrhythmias in Outpatients in the Republic of Georgia: A Brief Report of a Pilot Study

    OpenAIRE

    Kirtava, Zviad; Gegenava, Thea; Gegenava, Maka; Matoshvili, Zviad; Kasradze, Sofia; Kasradze, Pavle

    2012-01-01

    As the very first trial of mobile telemedicine in the Republic of Georgia, in June–December 2010 we investigated 35 outpatients with different types of arrhythmia (male/female ratio=16/19; 12–80 years old), among them 5 patients with concomitant epilepsy. The control group comprised 7 clinically healthy sportsmen (soccer players, all men; 15–17 years old), during a 30-min velo ergometer stress test. A three-lead electrocardiogram (ECG) loop recorder (Vitaphone BT 3300; Vitasystems GmbH, Mannh...

  18. Dental caries, periodontal disease, and cardiac arrhythmias in community-dwelling older persons aged 80 and older: is there a link?

    DEFF Research Database (Denmark)

    Holm-Pedersen, Poul; Avlund, Kirsten; Morse, Douglas E;

    2005-01-01

    lesions had 2.8 times higher odds (95% confidence interval=1.1-7.0) of arrhythmia than persons without active coronal caries, but there was no greater risk for persons with three or more coronal caries lesions. There was no association between periodontal disease and arrhythmia. CONCLUSION: The findings......OBJECTIVES: To examine whether caries or periodontitis is associated with cardiac arrhythmias in community-dwelling people aged 80 and older. SETTING: Urban, community-based population in Stockholm, Sweden. DESIGN: Cross-sectional. PARTICIPANTS: Eligible persons were identified through...... by a physician or the Stockholm Inpatient Register. Active root caries, active coronal caries, and periodontitis were assessed using previously defined National Institute of Dental and Craniofacial Research diagnostic criteria. RESULTS: The primary finding of the multivariate logistic regression analysis...

  19. Progress in Investigations of Arrhythmias Originating in the Right Ventricle%右室相关心律失常的临床和基础

    Institute of Scientific and Technical Information of China (English)

    胡金柱; 洪葵

    2011-01-01

    The structural and electrical remodeling in the left ventricle as a result of coronary heart disease and cardiomyopathy is the primary cause of ventricular arrhythmia and sudden cardiac death. However, arrhythmias can also originate in the right ventricle. Ventricular arrhythmias originating in the right ventricle usually affect younger patients, and can also lead to sudden cardiac death. Advances in available research techniques are providing more information about the pathogenesis, diagnosis and prognosis of right ventricular arrhythmias. Arrhyth-mias originating in the right ventricle mostly occur in arrhythmogenic right ventricular cardiomyopathy/dysplasia, Brugada syndrome, right ventricular outflow tract ventricular tachycardia, and congenital heart defects. This article reviews recent research in these diseases and their connection to right ventricular arrhythmias.%冠心病或心肌病所致左室结构和电重构是室性心律失常和心源性猝死发生的主要原因.近20年来,右室相关心律失常已受到工作者重视,其好发于青壮年患者,易导致心源性猝死,基础研究尤其是分子遗传学的发展推动了人们对右室相关心律失常发病机制、诊断和预后的认识和理解.右室相关心律失常多见于致心律失常型右室心肌病、Brugada综合征、右室流出道室性心动过速及先天性心脏病等,现将对其临床与基础研究进行概述.

  20. Neck heart syndrome arrhythmia 16 cases of clinical analysis%颈心综合征16例临床分析

    Institute of Scientific and Technical Information of China (English)

    赵淑萍; 尉双玲; 郎明丽

    2013-01-01

    目的探讨颈心综合征致心律失常的诊断、治疗及病因。方法回顾性分析我科2008年-2012年收治的16例颈椎病引起心律失常的诊断、治疗及病情转归情况。结果本组16例在明确心律失常系颈心综合征引起后,治疗原发病,心律失常均得到控制。结论颈心综合征发作时可导致心律失常的发生,明确诊断后积极治疗颈椎病会提高抗心律失常疗效,临床上要提高对颈椎病导致心律失常的认识,避免延误诊治。%Objective To explore neck heart syndrome to diagnosis, treatment and the causes of arrhythmias. Methods To analyze the I division in 2008-2012 treated 16 cases of cervical spondylosis cause disease diagnosis , treatment and outcome of cardiac arrhythmias. Results Of 16 cases in clear arrhythmia heart syndrome caused by neck, after treatment of primary disease, arrhythmia under control. Conclusion Cervical syndrome of heart attack can cause cardiac arrhythmia occurs, active treatment after diagnosis of cervical spondylosis can improve the anti-arrhythmic effects, so to improve clinical understanding of cervical vertebra disease cause arrhythmia, to avoid delay in diagnosis and treatment.

  1. The Utility of Ambulatory Electrocardiographic Monitoring for Detecting Silent Arrhythmias and Clarifying Symptom Mechanism in an Elderly Urban Population with Heart Failure and Hypertension: Clinical Implications

    Directory of Open Access Journals (Sweden)

    Kathleen T. Hickey

    2010-06-01

    Full Text Available Background : Atrial and ventriclar tachyarrhythmias, as well as bradyarrhythmias, in the elderly with heart failure (HF and/or hypertension (HTN have been well documented. However, the frequency of these arrhythmias, whether silent or symptomatic, and their association with subsequent cardiac events has not been well defi ned in patients 65 years or older with HF and other cardiovascular risk factors. Objective : To assess the value of 2 weeks of remote, transtelephonic cardiac monitoring for detecting arrhythmias in an elderly, urban population living with HF. Methods : Fi” y-four patients with a history of systolic HF and/or HTN were consented and enrolled. All wore an auto triggered cardiac loop monitor for 2 weeks that captures EKG data and both silent and symptomatic arrhythmias were recorded. Results : Mean age was 73 ± 6 years with 59% of subjects were females, 74% Hispanic, 22% black, and 4% white/other. All patients had HF and 94% had HTN. From the cardiac monitoring, 72% demonstrated ectopic atrial and ventricular activity, and 1 paroxysmal episode of atrial fi brillation was documented. In addition, 3 subjects had signifi cant non-sustained ventricular tachycardia, and 4 individuals had severe bradycardia recorded on cardiac monitoring. These 7 individuals underwent placement of an implantable cardioverter defi brillator (ICD or pacemaker based on the documented arrhythmias which may have otherwise gone undetected. Conclusions : TA substantial proportion of patients exhibited cardiac arrhythmias. Future morbidity was prevented because of the detection of arrhythmias on monitoring that led to specifi c therapies such as pacemaker or ICD implantation which otherwise may not have been implemented.

  2. Prognostic significance of electrical alternans versus signal averaged electrocardiography in predicting the outcome of electrophysiological testing and arrhythmia-free survival

    Science.gov (United States)

    Armoundas, A. A.; Rosenbaum, D. S.; Ruskin, J. N.; Garan, H.; Cohen, R. J.

    1998-01-01

    OBJECTIVE: To investigate the accuracy of signal averaged electrocardiography (SAECG) and measurement of microvolt level T wave alternans as predictors of susceptibility to ventricular arrhythmias. DESIGN: Analysis of new data from a previously published prospective investigation. SETTING: Electrophysiology laboratory of a major referral hospital. PATIENTS AND INTERVENTIONS: 43 patients, not on class I or class III antiarrhythmic drug treatment, undergoing invasive electrophysiological testing had SAECG and T wave alternans measurements. The SAECG was considered positive in the presence of one (SAECG-I) or two (SAECG-II) of three standard criteria. T wave alternans was considered positive if the alternans ratio exceeded 3.0. MAIN OUTCOME MEASURES: Inducibility of sustained ventricular tachycardia or fibrillation during electrophysiological testing, and 20 month arrhythmia-free survival. RESULTS: The accuracy of T wave alternans in predicting the outcome of electrophysiological testing was 84% (p < 0.0001). Neither SAECG-I (accuracy 60%; p < 0.29) nor SAECG-II (accuracy 71%; p < 0.10) was a statistically significant predictor of electrophysiological testing. SAECG, T wave alternans, electrophysiological testing, and follow up data were available in 36 patients while not on class I or III antiarrhythmic agents. The accuracy of T wave alternans in predicting the outcome of arrhythmia-free survival was 86% (p < 0.030). Neither SAECG-I (accuracy 65%; p < 0.21) nor SAECG-II (accuracy 71%; p < 0.48) was a statistically significant predictor of arrhythmia-free survival. CONCLUSIONS: T wave alternans was a highly significant predictor of the outcome of electrophysiological testing and arrhythmia-free survival, while SAECG was not a statistically significant predictor. Although these results need to be confirmed in prospective clinical studies, they suggest that T wave alternans may serve as a non-invasive probe for screening high risk populations for malignant ventricular

  3. High-throughput cardiac safety evaluation and multi-parameter arrhythmia profiling of cardiomyocytes using microelectrode arrays.

    Science.gov (United States)

    Gilchrist, Kristin H; Lewis, Gregory F; Gay, Elaine A; Sellgren, Katelyn L; Grego, Sonia

    2015-10-15

    Microelectrode arrays (MEAs) recording extracellular field potentials of human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CM) provide a rich data set for functional assessment of drug response. The aim of this work is the development of a method for a systematic analysis of arrhythmia using MEAs, with emphasis on the development of six parameters accounting for different types of cardiomyocyte signal irregularities. We describe a software approach to carry out such analysis automatically including generation of a heat map that enables quick visualization of arrhythmic liability of compounds. We also implemented signal processing techniques for reliable extraction of the repolarization peak for field potential duration (FPD) measurement even from recordings with low signal to noise ratios. We measured hiPS-CM's on a 48 well MEA system with 5minute recordings at multiple time points (0.5, 1, 2 and 4h) after drug exposure. We evaluated concentration responses for seven compounds with a combination of hERG, QT and clinical proarrhythmia properties: Verapamil, Ranolazine, Flecainide, Amiodarone, Ouabain, Cisapride, and Terfenadine. The predictive utility of MEA parameters as surrogates of these clinical effects were examined. The beat rate and FPD results exhibited good correlations with previous MEA studies in stem cell derived cardiomyocytes and clinical data. The six-parameter arrhythmia assessment exhibited excellent predictive agreement with the known arrhythmogenic potential of the tested compounds, and holds promise as a new method to predict arrhythmic liability. PMID:26232523

  4. The pioneering work of George Mines on cardiac arrhythmias: groundbreaking ideas that remain influential in contemporary cardiac electrophysiology.

    Science.gov (United States)

    Aguilar, Martin; Nattel, Stanley

    2016-05-01

    George Mines was a pioneering physiologist who, despite an extremely short period of professional activity and only primitive experimental methodology, succeeded in formulating concepts that continue to be of great influence today. Here, we review some of his most important discoveries and their impact on contemporary concepts and clinical practice. Mines' greatest contribution was his conceptualization and characterization of circus movement reentry. His observations and ideas about the basis for cardiac reentrant activity underlie how we understand and manage a wide range of important clinical rhythm disturbances today. The notions he introduced regarding the influence of premature extrastimuli on reentry (termination, resetting and entrainment) are central to contemporary assessment of arrhythmia mechanisms in clinical electrophysiology laboratories and modern device therapy of cardiac tachyarrhythmias. Refinements of his model of reentry have led to sophisticated biophysical theories of the mechanisms underlying cardiac fibrillation. His seminal observations on the influence of electrolyte derangements and autonomic tone on the heart are relevant to our understanding of the physiology and pharmacology of arrhythmias caused by cardiac pathology. In this era of advanced technology, it is important to appreciate that ideas of lasting impact come from great minds and do not necessarily require great tools. PMID:26607760

  5. P wave detection in ECG signals using an extended Kalman filter: an evaluation in different arrhythmia contexts.

    Science.gov (United States)

    Rahimpour, M; Mohammadzadeh Asl, B

    2016-07-01

    Monitoring atrial activity via P waves, is an important feature of the arrhythmia detection procedure. The aim of this paper is to present an algorithm for P wave detection in normal and some abnormal records by improving existing methods in the field of signal processing. In contrast to the classical approaches, which are completely blind to signal dynamics, our proposed method uses the extended Kalman filter, EKF25, to estimate the state variables of the equations modeling the dynamic of an ECG signal. This method is a modified version of the nonlinear dynamical model previously introduced for a generation of synthetic ECG signals and fiducial point extraction in normal ones. It is capable of estimating the separate types of activity of the heart with reasonable accuracy and performs well in the presence of morphological variations in the waveforms and ectopic beats. The MIT-BIH Arrhythmia and QT databases have been used to evaluate the performance of the proposed method. The results show that this method has Se  =  98.38% and Pr  =  96.74% in the overall records (considering normal and abnormal rhythms). PMID:27321699

  6. P wave detection in ECG signals using an extended Kalman filter: an evaluation in different arrhythmia contexts.

    Science.gov (United States)

    Rahimpour, M; Mohammadzadeh Asl, B

    2016-07-01

    Monitoring atrial activity via P waves, is an important feature of the arrhythmia detection procedure. The aim of this paper is to present an algorithm for P wave detection in normal and some abnormal records by improving existing methods in the field of signal processing. In contrast to the classical approaches, which are completely blind to signal dynamics, our proposed method uses the extended Kalman filter, EKF25, to estimate the state variables of the equations modeling the dynamic of an ECG signal. This method is a modified version of the nonlinear dynamical model previously introduced for a generation of synthetic ECG signals and fiducial point extraction in normal ones. It is capable of estimating the separate types of activity of the heart with reasonable accuracy and performs well in the presence of morphological variations in the waveforms and ectopic beats. The MIT-BIH Arrhythmia and QT databases have been used to evaluate the performance of the proposed method. The results show that this method has Se  =  98.38% and Pr  =  96.74% in the overall records (considering normal and abnormal rhythms).

  7. Hospitalizations from Hypertensive Diseases, Diabetes, and Arrhythmia in Relation to Low and High Temperatures: Population-Based Study.

    Science.gov (United States)

    Bai, Li; Li, Qiongsi; Wang, Jun; Lavigne, Eric; Gasparrini, Antonio; Copes, Ray; Yagouti, Abderrahmane; Burnett, Richard T; Goldberg, Mark S; Villeneuve, Paul J; Cakmak, Sabit; Chen, Hong

    2016-01-01

    Little is known about the extent to which ambient temperatures contribute to the burden of hospitalizations from hypertensive diseases, diabetes, and arrhythmia. To fill this knowledge gap, we conducted a time-series study comprising entire population of Ontario, Canada during 1996-2013. A distributed lag non-linear model was developed to estimate the cumulative effect of temperatures over a 21-day lag period. We computed the burden of hospitalizations attributable to cold and heat. Furthermore, we separated the burden into components related to mild and extreme temperatures. Compared to the temperature with minimum risk of morbidity, cold temperatures (1(st) percentile) were associated with a 37% (95% confidence interval: 5%, 78%) increase in hypertension-related hospitalizations whereas no significant association with hot temperatures (99(th) percentile) was observed. Cold and hot temperatures were also associated with a 12% (1%, 24%) and a 30% (6%, 58%) increase in diabetes-related hospitalizations, respectively. Arrhythmia was not linked to temperatures. These estimates translate into ~10% of hypertension-related hospitalizations attributable to total cold, and ~9% from mild cold. Similarly, ~11% of diabetes-related hospitalizations were due to total heat, virtually all of which were from mild heat. In conclusion, ambient temperatures, especially in moderate ranges, contribute to excess hospitalizations from hypertension and diabetes. PMID:27456033

  8. Multigenerational links between mothers' experiences of autonomy in childhood and preschoolers' respiratory sinus arrhythmia: Variations by maltreatment status.

    Science.gov (United States)

    Noll, Laura K; Clark, Caron A C; Skowron, Elizabeth A

    2015-11-01

    Despite burgeoning evidence linking early exposure to child maltreatment (CM) to deficits in self-regulation, the pathways to strong regulatory development in these children are not well understood, and significant heterogeneity is observed in their outcomes. Experiences of autonomy may play a key role in transmitting self-regulatory capacity across generations and help explain individual differences in maltreatment outcomes. In this study, we investigated multigenerational associations between Generation 1 (G1)-Generation 2 (G2) mothers' early experience of warmth and autonomy in relation to their own mothers and their Generation 3 (G3) children's autonomic physiological regulation in CM (n = 85) and non-CM (n = 128) families. We found that G2 mothers who recalled greater autonomy in their childhood relationship with their G1 mothers had preschool-age G3 children with higher respiratory sinus arrhythmia at baseline when alone while engaged in individual challenge tasks, during social exchanges with their mother in joint challenge tasks, and during the portions of the strange situation procedure when the mother was present. Although no clear mediators of this association emerged, multigenerational links among G1-G2 relations, maternal representations of her child, child behavior, and child respiratory sinus arrhythmia differed by maltreatment status, thus possibly representing important targets for future research and intervention. PMID:26535936

  9. The Power of Exercise-Induced T-wave Alternans to Predict Ventricular Arrhythmias in Patients with Implanted Cardiac Defibrillator

    Directory of Open Access Journals (Sweden)

    Laura Burattini

    2013-01-01

    Full Text Available The power of exercise-induced T-wave alternans (TWA to predict the occurrence of ventricular arrhythmias was evaluated in 67 patients with an implanted cardiac defibrillator (ICD. During the 4-year follow-up, electrocardiographic (ECG tracings were recorded in a bicycle ergometer test with increasing workload ranging from zero (NoWL to the patient's maximal capacity (MaxWL. After the follow-up, patients were classified as either ICD_Cases (n = 29, if developed ventricular tachycardia/fibrillation, or ICD_Controls (n = 38. TWA was quantified using our heart-rate adaptive match filter. Compared to NoWL, MaxWL was characterized by faster heart rates and higher TWA in both ICD_Cases (12-18 μ V vs. 20-39 μ V; P < 0.05 and ICD_Controls (9-15 μ V vs. 20-32 μ V; P < 0.05. Still, TWA was able to discriminate the two ICD groups during NoWL (sensitivity = 59-83%, specificity = 53-84% but not MaxWL (sensitivity = 55-69%, specificity = 39-74%. Thus, this retrospective observational case-control study suggests that TWA's predictive power for the occurrence of ventricular arrhythmias could increase at low heart rates.

  10. Marine omega-3 highly unsaturated fatty acids: From mechanisms to clinical implications in heart failure and arrhythmias.

    Science.gov (United States)

    Glück, Tobias; Alter, Peter

    2016-07-01

    Therapeutic implications of marine omega-3 highly unsaturated fatty acids (HUFA) in cardiovascular disease are still discussed controversially. Several clinical trials report divergent findings and thus leave ambiguity on the meaning of oral omega-3 therapy. Potential prognostic indications of HUFA treatment have been predominantly studied in coronary artery disease, sudden cardiac death, ventricular arrhythmias, atrial fibrillation and heart failure of various origin. It is suspected that increased ventricular wall stress is crucially involved in the prognosis of heart failure. Increased wall stress and an unfavorable myocardial remodeling is associated with an increased risk of arrhythmias by stretch-activated membrane ion channels. Integration of HUFA into the microenvironment of cardiomyocyte ion channels lead to allosteric changes and increase the electrical stability. Increased ventricular wall stress appears to be involved in the local myocardial as well as in the hepatic fatty acid metabolism, i.e. a cardio-hepatic syndrome. Influences of an altered endogenous HUFA metabolism and an inverse shift of the fatty acid profile was underrated in the past. A better understanding of these interacting endogenous mechanisms appears to be required for interpreting the findings of recent experimental and clinical studies. The present article critically reviews major studies on basic pathophysiological mechanisms and treatment effects in clinical trials. PMID:27080538

  11. Comprehensive Analysis Elderly Health Check-up Asymptomatic Cardiac Arrhythmias%老年健康体检无症状心律失常综合分析

    Institute of Scientific and Technical Information of China (English)

    季敏娜

    2013-01-01

    Objective:To study the reasons and characteristics of asymptomatic cardiac arrhythmia in the elderly occur,and preventive measures. Method:880 cases of elderly patients with asymptomatic cardiac arrhythmia for the rural and urban residents in the free health checks,check diagnose by 12 lead ecg machine of arrhythmia patients and 1083 cases of elderly patients with symptomatic cardiac arrhythmias by combining synthetical consolidation and rehabilitation physical examination data,analysed the characteristics of asymptomatic cardiac arrhythmia and reason.Result:Senile asymptomatic cardiac arrhythmia obviously increased with age (P<0.01).Conclusion:The occurrence of senile asymptomatic cardiac arrhythmias have direct relationship with underlying heart disease,along with the age growth significantly higher incidence of arrhythmia,active prevention,diagnosis and treatment in time,can effectively reduce various cardiac risk the occurrence of adverse events.%目的:探讨老年人无症状心律失常发生的原因、特点、以及防范措施。方法:880例老年无症状心律失常患者为农村和城镇居民免费健康体检中通过十二导联心电图机检查确诊的心律失常患者,与1083例老年有症状的心律失常患者通过结合全身检查综合整理资料,分析无症状心律失常的特点与原因。结果:老年无症状心律失常随年龄增长而明显增多。结论:老年无症状心律失常的发生与基础心脏疾病有直接关系,随着年龄增长心律失常的发病率明显增高,积极预防,及时诊断治疗,可以有效减少各种心脏危险不良事件的发生。

  12. Stereotactic Arrhythmia Radioablation (STAR) of Ventricular Tachycardia: A Treatment Planning Study

    Science.gov (United States)

    Fahimian, Benjamin; Soltys, Scott G; Zei, Paul; Lo, Anthony; Gardner, Edward A; Maguire, Patrick J; Loo Jr., Billy W

    2016-01-01

    Purpose The first stereotactic arrhythmia radioablation (STAR) of ventricular tachycardia (VT) was delivered at Stanford on a robotic radiosurgery system (CyberKnife® G4) in 2012. The results warranted further investigation of this treatment. Here we compare dosimetrically three possible treatment delivery platforms for STAR. Methods The anatomy and target volume of the first treated patient were used for this study. A dose of 25 Gy in one fraction was prescribed to the planning target volume (PTV). Treatment plans were created on three treatment platforms: CyberKnife® G4 system with Iris collimator (Multiplan, V. 4.6)(Plan #1), CyberKnife® M6 system with InCise 2TM multileaf collimator (Multiplan V. 5.3)(Plan #2) and Varian TrueBeamTM STx with HD 120TM MLC and 10MV flattening filter free (FFF) beam (Eclipse planning system, V.11) (Plan #3 coplanar and #4 noncoplanar VMAT plans). The four plans were compared by prescription isodose line, plan conformity index, dose gradient, as well as dose to the nearby critical structures. To assess the delivery efficiency, planned monitor units (MU) and estimated treatment time were evaluated. Results Plans #1-4 delivered 25 Gy to the PTV to the 75.0%, 83.0%, 84.3%, and 84.9% isodose lines and with conformity indices of 1.19, 1.16, 1.05, and 1.05, respectively. The dose gradients for plans #1-4 were 3.62, 3.42, 3.93, and 3.73 with the CyberKnife® MLC plan (Plan #2) the best, and the TrueBeamTM STx co-planar plan (Plan #3) the worst. The dose to nearby critical structures (lung, stomach, bowel, and esophagus) were all well within tolerance. The MUs for plans #1-4 were 27671, 16522, 6275, and 6004 for an estimated total-treatment-time/beam-delivery-time of 99/69, 65/35, 37/7, and 56/6 minutes, respectively, under the assumption of 30 minutes pretreatment setup time. For VMAT gated delivery, a 40% duty cycle, 2400MU/minute dose rate, and an extra 10 minutes per extra arc were assumed. Conclusion Clinically acceptable plans were

  13. Mapping epicardial fat with multi-detector computed tomography to facilitate percutaneous transepicardial arrhythmia ablation

    Energy Technology Data Exchange (ETDEWEB)

    Abbara, Suhny [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)]. E-mail: Sabbara@partners.org; Desai, Jay C. [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Cury, Ricardo C. [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Butler, Javed [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Nieman, Koen [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Reddy, Vivek [Division of Cardiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)

    2006-03-15

    A sizable portion of ventricular tachycardia circuits are epicardial, especially in patients with non-ischemic cardiomyopathy, e.g. Chagas disease. Thus there is a growing interest among the electrophysiologists in transepicardial mapping and myocardial ablation for treatment of arrhythmias. However, increased epicardial fat can be a significant hindrance in procedural success as it can mimic infarct during mapping and can also decrease the effectiveness of ablation. Quantitative knowledge of epicardial fat pre-procedure can potentially significantly facilitate the conduct and outcomes of these procedures. In this study we assessed the epicardial fat distribution and thickness in vivo in 59 patients who underwent multi-detector computed tomography (MDCT) for coronary artery assessment using a 16-slice scanner. Multiplanar reconstructions were obtained in the ventricular short axis at the basal, mid ventricular, and near the apex level, and in a four-chamber view. In the short axis slices, we measured epicardial fat diameter in nine segments, and in the four-chamber view, it was measured in five segments. In grooved segments the maximum fat thickness was recorded, while in non-grooved segments thickness at three equally spaced points were averaged. The results were as follows starting clockwise: superior inter-ventricular (IV) groove (all measurements are in mm, in basal, mid ventricular, and apical levels, respectively) (11.2, 8.6, 7.3), left ventricular (LV) superior lateral wall (1.0, 1.5, 1.7), LV inferior lateral wall (1.3, 2.2, 3.5), inferior IV groove (9.2, 6.5, 6.1), right ventricular (RV) diaphragmatic wall (1.4, 0.2, 1.0), acute margin (9.2, 7.3, 7.8), RV anterior free wall inferior (6.8, 4.0, 4.7), RV anterior free wall superior (6.5, 3.2, 3.1), RV superior wall (5.6, 2.7, 4.0), We measured the following four-chamber segments: LV apex (2.8 mm), left atrio-ventricular (AV) groove (12.7), right AV groove (14.8), RV apex (4.8), and anterior IV groove (7

  14. Mapping epicardial fat with multi-detector computed tomography to facilitate percutaneous transepicardial arrhythmia ablation

    International Nuclear Information System (INIS)

    A sizable portion of ventricular tachycardia circuits are epicardial, especially in patients with non-ischemic cardiomyopathy, e.g. Chagas disease. Thus there is a growing interest among the electrophysiologists in transepicardial mapping and myocardial ablation for treatment of arrhythmias. However, increased epicardial fat can be a significant hindrance in procedural success as it can mimic infarct during mapping and can also decrease the effectiveness of ablation. Quantitative knowledge of epicardial fat pre-procedure can potentially significantly facilitate the conduct and outcomes of these procedures. In this study we assessed the epicardial fat distribution and thickness in vivo in 59 patients who underwent multi-detector computed tomography (MDCT) for coronary artery assessment using a 16-slice scanner. Multiplanar reconstructions were obtained in the ventricular short axis at the basal, mid ventricular, and near the apex level, and in a four-chamber view. In the short axis slices, we measured epicardial fat diameter in nine segments, and in the four-chamber view, it was measured in five segments. In grooved segments the maximum fat thickness was recorded, while in non-grooved segments thickness at three equally spaced points were averaged. The results were as follows starting clockwise: superior inter-ventricular (IV) groove (all measurements are in mm, in basal, mid ventricular, and apical levels, respectively) (11.2, 8.6, 7.3), left ventricular (LV) superior lateral wall (1.0, 1.5, 1.7), LV inferior lateral wall (1.3, 2.2, 3.5), inferior IV groove (9.2, 6.5, 6.1), right ventricular (RV) diaphragmatic wall (1.4, 0.2, 1.0), acute margin (9.2, 7.3, 7.8), RV anterior free wall inferior (6.8, 4.0, 4.7), RV anterior free wall superior (6.5, 3.2, 3.1), RV superior wall (5.6, 2.7, 4.0), We measured the following four-chamber segments: LV apex (2.8 mm), left atrio-ventricular (AV) groove (12.7), right AV groove (14.8), RV apex (4.8), and anterior IV groove (7

  15. Increased short-term variability of the QT interval in professional soccer players: possible implications for arrhythmia prediction.

    Directory of Open Access Journals (Sweden)

    Csaba Lengyel

    Full Text Available BACKGROUND: Sudden cardiac death in competitive athletes is rare but it is significantly more frequent than in the normal population. The exact cause is seldom established and is mostly attributed to ventricular fibrillation. Myocardial hypertrophy and slow heart rate, both characteristic changes in top athletes in response to physical conditioning, could be associated with increased propensity for ventricular arrhythmias. We investigated conventional ECG parameters and temporal short-term beat-to-beat variability of repolarization (STV(QT, a presumptive novel parameter for arrhythmia prediction, in professional soccer players. METHODS: Five-minute 12-lead electrocardiograms were recorded from professional soccer players (n = 76, all males, age 22.0±0.61 years and age-matched healthy volunteers who do not participate in competitive sports (n = 76, all males, age 22.0±0.54 years. The ECGs were digitized and evaluated off-line. The temporal instability of beat-to-beat heart rate and repolarization were characterized by the calculation of short-term variability of the RR and QT intervals. RESULTS: Heart rate was significantly lower in professional soccer players at rest (61±1.2 vs. 72±1.5/min in controls. The QT interval was prolonged in players at rest (419±3.1 vs. 390±3.6 in controls, p<0.001. QTc was significantly longer in players compared to controls calculated with Fridericia and Hodges correction formulas. Importantly, STV(QT was significantly higher in players both at rest and immediately after the game compared to controls (4.8±0.14 and 4.3±0.14 vs. 3.5±0.10 ms, both p<0.001, respectively. CONCLUSIONS: STV(QT is significantly higher in professional soccer players compared to age-matched controls, however, further studies are needed to relate this finding to increased arrhythmia propensity in this population.

  16. Aconitine-induced Ca2+ overload causes arrhythmia and triggers apoptosis through p38 MAPK signaling pathway in rats

    International Nuclear Information System (INIS)

    Aconitine is a major bioactive diterpenoid alkaloid with high content derived from herbal aconitum plants. Emerging evidence indicates that voltage-dependent Na+ channels have pivotal roles in the cardiotoxicity of aconitine. However, no reports are available on the role of Ca2+ in aconitine poisoning. In this study, we explored the importance of pathological Ca2+ signaling in aconitine poisoning in vitro and in vivo. We found that Ca2+ overload lead to accelerated beating rhythm in adult rat ventricular myocytes and caused arrhythmia in conscious freely moving rats. To investigate effects of aconitine on myocardial injury, we performed cytotoxicity assay in neonatal rat ventricular myocytes (NRVMs), as well as measured lactate dehydrogenase level in the culture medium of NRVMs and activities of serum cardiac enzymes in rats. The results showed that aconitine resulted in myocardial injury and reduced NRVMs viability dose-dependently. To confirm the pro-apoptotic effects, we performed flow cytometric detection, cardiac histology, transmission electron microscopy and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. The results showed that aconitine stimulated apoptosis time-dependently. The expression analysis of Ca2+ handling proteins demonstrated that aconitine promoted Ca2+ overload through the expression regulation of Ca2+ handling proteins. The expression analysis of apoptosis-related proteins revealed that pro-apoptotic protein expression was upregulated, and anti-apoptotic protein BCL-2 expression was downregulated. Furthermore, increased phosphorylation of MAPK family members, especially the P-P38/P38 ratio was found in cardiac tissues. Hence, our results suggest that aconitine significantly aggravates Ca2+ overload and causes arrhythmia and finally promotes apoptotic development via phosphorylation of P38 mitogen-activated protein kinase. - Highlights: • Aconitine-induced Ca2+ overload causes arrhythmia in rats.

  17. Cardiac Atrophy and Diastolic Dysfunction During and After Long Duration Spaceflight: Functional Consequences for Orthostatic Intolerance, Exercise Capability and Risk for Cardiac Arrhythmias

    Science.gov (United States)

    Levine, Benjamin D.; Bungo, Michael W.; Platts, Steven H.; Hamilton, Douglas R.; Johnston, Smith L.

    2009-01-01

    Cardiac Atrophy and Diastolic Dysfunction During and After Long Duration Spaceflight: Functional Consequences for Orthostatic Intolerance, Exercise Capability and Risk for Cardiac Arrhythmias (Integrated Cardiovascular) will quantify the extent of long-duration space flightassociated cardiac atrophy (deterioration) on the International Space Station crewmembers.

  18. Effects of glucose-insulin-potassium on baroreflex sensitivity, left ventricular function and ventricular arrhythmia in the subacute phase of myocardial infarction in rats

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-Guo; SHU He; SHEN Fu-Ming; MIAO Chao-Yu; SU Ding-Feng

    2004-01-01

    Objective:Glucose-insulin-potassium(GIK) is clinically used for reducing mortality in acute myocardial infarction(MI). It is known that ventricular arrhythmia, left ventricular dysfunction and impaired baroreflex sensitivity(BRS) are the three major determinants for predicting the mortality after acute MI. The present work was designed to study the effects of GIK on BRS, ventricular arrhythmia, and left ventricular function in rats with coronary artery ligature. Sprague-Dawley rats were used and the myocardial infarction was produced by ligature of the left anterior descending artery. Five weeks after coronary artery ligation, BRS was measured in conscious state with a computerized blood pressure monitoring system and left ventricular function and electrocardiogram were determined in the anaesthetized state in the subacute phase of myocardial infarction. It was found that GIK did not affect the blood pressure and heart period in both conscious and anaesthetized rats. GIK did not enhance BRS, but reduced ventricular arrhythmia and improved left ventricular function by reducing left ventricular end diastolic pressure in anaesthetized rats with MI. It is proposed that reducing ventricular arrhythmia and improving left ventricular function contribute to the effect of GIK on reducing the mortality after MI.

  19. ELECTROPHARMACOLOGIC EFFECTS AND PHARMACOKINETICS OF ALMOKALANT, A NEW CLASS-III ANTIARRHYTHMIC, IN PATIENTS WITH HEALED OR HEALING MYOCARDIAL INFARCTS AND COMPLEX VENTRICULAR ARRHYTHMIAS

    NARCIS (Netherlands)

    WIESFELD, ACP; CRIJNS, HJGM; TOBE, TJM; ALMGREN, O; BERGSTRAND, RH; ABERG, J; HAAKSMA, J; LIE, KI

    1992-01-01

    The electropharmacologic effects and pharmacokinetics of almokalant, a new class III antiarrhythmic, were investigated in a randomized, placebo-controlled, double-blind study, and efficacy was evaluated. Ten post-myocardial infarction patients with complex ventricular arrhythmias were included and r

  20. Effect of Fish Oil on Ventricular Tachyarrhythmia and Death in Patients With Implantable Cardioverter Defibrillators: The Study on Omega-3 Fatty Acids and Ventricular Arrhythmia (SOFA) Randomized Trial

    NARCIS (Netherlands)

    Brouwer, I.A.; Zock, P.L.; Camm, A.J.; Bocker, D.; Hauer, R.N.W.; Wever, E.F.D.; Dullemeijer, C.; Ronden, J.E.; Katan, M.B.; Lubinski, A.; Buschler, H.; Schouten, E.G.

    2006-01-01

    Context Very-long-chain n-3 polyunsaturated fatty acids (omega-3 PUFAs) from fish are thought to reduce risk of sudden death, possibly by reducing susceptibility to cardiac arrhythmia. Objective To study the effect of supplemental fish oil vs placebo on ventricular tachyarrhythmia or death. Design,

  1. Curative Effect Observation on Amiodarone in the Treatment of Arrhythmia%胺碘酮治疗心律失常的临床疗效观察

    Institute of Scientific and Technical Information of China (English)

    李光立; 李玲

    2014-01-01

    Objective:To explore the arrhythmia outcomes in patients treated with amiodarone. Method:49 patients were treated with arrhythmia. Result:34 cases were markedly improved(69.4%),effective in 11 cases (accounting for 22.4%),4 cases were ineffective(8.2%),the total effective rate was 91.8%. Conclusion:Oral application of amiodarone in the treatment of arrhythmia in clinical effect is good,and can significantly improve cardiac arrhythmia patients,high security,small side effects,with the value of clinical application and promotion.%目的:探讨心律失常患者采用胺碘酮治疗的疗效。方法:对49例心律失常患者进行胺碘酮治疗。结果:显效34例(69.4%),有效11例(22.4%),无效4例(8.2%),总有效率为91.8%。结论:口服应用胺碘酮在治疗心律失常方面临床效果好,能够明显改善心律失常患者病情,安全性高,副作用小,具有临床应用与推广的价值。

  2. Delayed-enhancement MRI of apical hypertrophic cardiomyopathy: assessment of the intramural distribution and comparison with clinical symptoms, ventricular arrhythmias, and cine MRI

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Yasuo; Fukushima, Yoshimitsu; Kumita, Shinichiro (Dept. of Radiology, Nippon Medical School, Tokyo (Japan)), email: yas-amano@nifty.com; Takayama, Morimasa (Dept. of Cardiology, Sakakibara Heart Inst., Tokyo (Japan)); Kitamura, Mitsunobu (Coronary Care Unit, Chiba-Hokuso Hospital of Nippon Medical School, Chiba (Japan))

    2011-07-15

    Background: Hypertrophic cardiomyopathy (HCM) is reported to show patchy midwall myocardial hyper enhancement on delayed-enhancement magnetic resonance imaging (DE-MRI). The intramural distribution of myocardial hyper enhancement and its correlation with clinical symptoms, ventricular arrhythmias, and cardiac function have not been described for symptomatic apical HCM. Purpose: To evaluate the features and significance of myocardial hyper enhancement on DE-MRI in symptomatic apical HCM. Material and Methods: Thirteen patients with symptomatic apical HCM and their 65 apical segments were investigated. Myocardial hyper enhancement and regional and global functional parameters were determined with MRI. We investigated the intramural distribution and frequencies of this myocardial hyper enhancement and compared them with the patients' clinical symptoms, the presence of ventricular arrhythmias, and cine MRI. Results: Eight (61.5%) patients with symptomatic apical HCM displayed apical myocardial hyper enhancement, and 22 (33.8%) of the 65 apical segments examined showed myocardial hyper enhancement. Of the myocardial hyper enhancement observed, 81.8% showed a subendocardial pattern.The Hyperenhanced apical myocardium had a lower percentage of systolic myocardial thickening, and was associated with serious symptoms (e.g. syncope) and ventricular arrhythmias. Conclusion: Patients with symptomatic apical HCM showed myocardial hyper enhancement involving the subendocardial layer, which might be related to regional systolic dysfunction, serious clinical symptoms, and ventricular arrhythmias

  3. T-wave alternans and dispersion of the QT interval as risk stratification markers in patients susceptible to sustained ventricular arrhythmias

    Science.gov (United States)

    Armoundas, A. A.; Osaka, M.; Mela, T.; Rosenbaum, D. S.; Ruskin, J. N.; Garan, H.; Cohen, R. J.

    1998-01-01

    T-wave alternans and QT dispersion were compared as predictors of the outcome of electrophysiologic study and arrhythmia-free survival in patients undergoing electrophysiologic evaluation. T-wave alternans was a highly significant predictor of these 2 outcome variables, whereas QT dispersion was not.

  4. The effects of B0, B20 and B100 soy biodiesel exhaust on aconitine-induced cardiac arrhythmia in spontaneously hypertensive rats

    Science.gov (United States)

    CONTEXT: Diesel exhaust (DE) has been shown to increase the risk of cardiac arrhythmias. Although biodiesel has been proposed as a "safer" alternative to diesel, it is still uncertain whether it actually poses less threat.OBJECTIVE: We hypothesized that exposure to pure or 20% so...

  5. Air pollution and incidence of cardiac arrhythmia; Pollution de l'air et incidence de l'arythmie cardiaque

    Energy Technology Data Exchange (ETDEWEB)

    Peters, A.; Liu, E.; Verrier, R.L.; Schwartz, J.; Gold, D.R.; Mittleman, M.; Baliff, J.; Oh, J.A.; Allen, G.; Monahan, K.; Dockery, D.W.

    2001-01-01

    The aim of this pilot study is the evaluation of the feasibility of short-dated relations analysis between the atmospheric pollutant level and the incidence of cardiac arrhythmia or ventricular fibrillation for automatic defibrillator carrier patients. (A.L.B.)

  6. Predictors of cardiac arrhythmias in the postoperative period by echocardiography, tissue Doppler and speckle tracking in patients with congenital heart diseases

    Directory of Open Access Journals (Sweden)

    Averina I.I.

    2015-09-01

    Conclusion. The indicators with predictive value for the arrhythmia in the postoperative period reflect the universal process of remodeling with the development of diastolic and systolic dysfunction, damage of longitudinal and circular functions of LV, longitudinal function of left atrium and the mitral valve function.

  7. Ablation of triadin causes loss of cardiac Ca2+ release units, impaired excitation-contraction coupling, and cardiac arrhythmias.

    Science.gov (United States)

    Chopra, Nagesh; Yang, Tao; Asghari, Parisa; Moore, Edwin D; Huke, Sabine; Akin, Brandy; Cattolica, Robert A; Perez, Claudio F; Hlaing, Thinn; Knollmann-Ritschel, Barbara E C; Jones, Larry R; Pessah, Isaac N; Allen, Paul D; Franzini-Armstrong, Clara; Knollmann, Björn C

    2009-05-01

    Heart muscle excitation-contraction (E-C) coupling is governed by Ca(2+) release units (CRUs) whereby Ca(2+) influx via L-type Ca(2+) channels (Cav1.2) triggers Ca(2+) release from juxtaposed Ca(2+) release channels (RyR2) located in junctional sarcoplasmic reticulum (jSR). Although studies suggest that the jSR protein triadin anchors cardiac calsequestrin (Casq2) to RyR2, its contribution to E-C coupling remains unclear. Here, we identify the role of triadin using mice with ablation of the Trdn gene (Trdn(-/-)). The structure and protein composition of the cardiac CRU is significantly altered in Trdn(-/-) hearts. jSR proteins (RyR2, Casq2, junctin, and junctophilin 1 and 2) are significantly reduced in Trdn(-/-) hearts, whereas Cav1.2 and SERCA2a remain unchanged. Electron microscopy shows fragmentation and an overall 50% reduction in the contacts between jSR and T-tubules. Immunolabeling experiments show reduced colocalization of Cav1.2 with RyR2 and substantial Casq2 labeling outside of the jSR in Trdn(-/-) myocytes. CRU function is impaired in Trdn(-/-) myocytes, with reduced SR Ca(2+) release and impaired negative feedback of SR Ca(2+) release on Cav1.2 Ca(2+) currents (I(Ca)). Uninhibited Ca(2+) influx via I(Ca) likely contributes to Ca(2+) overload and results in spontaneous SR Ca(2+) releases upon beta-adrenergic receptor stimulation with isoproterenol in Trdn(-/-) myocytes, and ventricular arrhythmias in Trdn(-/-) mice. We conclude that triadin is critically important for maintaining the structural and functional integrity of the cardiac CRU; triadin loss and the resulting alterations in CRU structure and protein composition impairs E-C coupling and renders hearts susceptible to ventricular arrhythmias. PMID:19383796

  8. Capturing Pain in the Cortex during General Anesthesia: Near Infrared Spectroscopy Measures in Patients Undergoing Catheter Ablation of Arrhythmias.

    Directory of Open Access Journals (Sweden)

    Barry D Kussman

    Full Text Available The predictability of pain makes surgery an ideal model for the study of pain and the development of strategies for analgesia and reduction of perioperative pain. As functional near-infrared spectroscopy reproduces the known functional magnetic resonance imaging activations in response to a painful stimulus, we evaluated the feasibility of functional near-infrared spectroscopy to measure cortical responses to noxious stimulation during general anesthesia. A multichannel continuous wave near-infrared imager was used to measure somatosensory and frontal cortical activation in patients undergoing catheter ablation of arrhythmias under general anesthesia. Anesthetic technique was standardized and intraoperative NIRS signals recorded continuously with markers placed in the data set for the timing and duration of each cardiac ablation event. Frontal cortical signals only were suitable for analysis in five of eight patients studied (mean age 14 ± 1 years, weight 66.7 ± 17.6 kg, 2 males. Thirty ablative lesions were recorded for the five patients. Radiofrequency or cryoablation was temporally associated with a hemodynamic response function in the frontal cortex characterized by a significant decrease in oxyhemoglobin concentration (paired t-test, p<0.05 with the nadir occurring in the period 4 to 6 seconds after application of the ablative lesion. Cortical signals produced by catheter ablation of arrhythmias in patients under general anesthesia mirrored those seen with noxious stimulation in awake, healthy volunteers, during sedation for colonoscopy, and functional Magnetic Resonance Imaging activations in response to pain. This study demonstrates the feasibility and potential utility of functional near-infrared spectroscopy as an objective measure of cortical activation under general anesthesia.

  9. Real-time arrhythmia detection with supplementary ECG quality and pulse wave monitoring for the reduction of false alarms in ICUs.

    Science.gov (United States)

    Krasteva, Vessela; Jekova, Irena; Leber, Remo; Schmid, Ramun; Abächerli, Roger

    2016-08-01

    False intensive care unit (ICU) alarms induce stress in both patients and clinical staff and decrease the quality of care, thus significantly increasing both the hospital recovery time and rehospitalization rates. In the PhysioNet/CinC Challenge 2015 for reducing false arrhythmia alarms in ICU bedside monitor data, this paper validates the application of a real-time arrhythmia detection library (ADLib, Schiller AG) for the robust detection of five types of life-threatening arrhythmia alarms. The strength of the application is to give immediate feedback on the arrhythmia event within a scan interval of 3 s-7.5 s, and to increase the noise immunity of electrocardiogram (ECG) arrhythmia analysis by fusing its decision with supplementary ECG quality interpretation and real-time pulse wave monitoring (quality and hemodynamics) using arterial blood pressure or photoplethysmographic signals. We achieved the third-ranked real-time score (79.41) in the challenge (Event 1), however, the rank was not officially recognized due to the 'closed-source' entry. This study shows the optimization of the alarm decision module, using tunable parameters such as the scan interval, lead quality threshold, and pulse wave features, with a follow-up improvement of the real-time score (80.07). The performance (true positive rate, true negative rate) is reported in the blinded challenge test set for different arrhythmias: asystole (83%, 96%), extreme bradycardia (100%, 90%), extreme tachycardia (98%, 80%), ventricular tachycardia (84%, 82%), and ventricular fibrillation (78%, 84%). Another part of this study considers the validation of ADLib with four reference ECG databases (AHA, EDB, SVDB, MIT-BIH) according to the international recommendations for performance reports in ECG monitors (ANSI/AAMI EC57). The sensitivity (Se) and positive predictivity (+P) are: QRS detector QRS (Se, +P)  >  99.7%, ventricular ectopic beat (VEB) classifier VEB (Se, +P)  =  95%, and ventricular

  10. Respiratory sinus arrhythmia during anaesthesia: assessment of respiration related beat-to-beat heart rate variability analysis methods.

    Science.gov (United States)

    Loula, P; Jäntti, V; Yli-Hankala, A

    1997-11-01

    Beat-to-beat heart rate variability analysis is a powerful tool for the diagnosis of neuropathy. Respiration-related heart rate variability (respiratory sinus arrhythmia, RSA) reflects the function of parasympathetic nervous system during spontaneous ventilation while awake. RSA is also claimed to monitor the depth of anaesthesia. Power spectrum analysis or various averaging techniques of the heart rate variability are usually applied. The current literature, however, does not usually interpret the ground rules and limitations of the method used, and this may sometimes lead to erroneous conclusions on the data. The aim of our study was to compare and analyse critically the performance of different methods of evaluating RSA during anaesthesia and positive pressure ventilation. Power spectrum analysis, the root mean square of the successive RR-interval difference (RMSSD), and two respiration related methods, RSA index and average phase RSA, were included in the comparison. To test these methods, 11 patients were anaesthetised with isoflurane and their lungs were ventilated mechanically with a frequency of 6 cycles min-1. Each patient received a bolus dose of atropine (20 micrograms kg-1) during the trial. Electrocardiogram, electroencephalogram and tracheal pressure signal from respirator were recorded and analyses were performed off-line. We demonstrated that general indices, such as RMSSD, may be strongly affected by heart rate level and other non-respiration related variations in heart rate. We also showed that the effect of unwanted fluctuations on RSA can be reduced with respiration dependent beat-to-beat methods. Furthermore we confirmed that in addition to the amplitude, also the pattern of respiratory sinus arrhythmia is of interest: the pattern is reversed in phase compared to spontaneous breathing while awake, as we have shown earlier. To analyse RSA during anaesthesia, we recommend the use of an average phase RSA method based on beat-to-beat variability

  11. Marshall束电生理特性及相关的房性心律失常%Electrophysiological Characteristics of Marshall Bundle and Its Related Atrial Arrhythmia

    Institute of Scientific and Technical Information of China (English)

    李蕾; 刘书旺(综述)

    2016-01-01

    Although the ligament of Marshall ( LOM) has been implicated in the genesis of atrial arrhythmia , the important cardiac muscle fibers ( Marshall bundles , MB) within this LOM is not well concerned .The paper reviews the anatomy of MB and its electrophysio-logical characteristics and mechanism in atrial arrhythmia .%已知Marshall韧带参与了房性心律失常的发生和维持,然而,其中起关键作用的肌性结构———Marshall束尚无详细报道。现就Marshall束的解剖及其在房性心律失常中的电生理特性、折返机制和研究进展做一综述。

  12. Arrhythmia Identification with Two-Lead Electrocardiograms Using Artificial Neural Networks and Support Vector Machines for a Portable ECG Monitor System

    Directory of Open Access Journals (Sweden)

    Shing-Hong Liu

    2013-01-01

    Full Text Available An automatic configuration that can detect the position of R-waves, classify the normal sinus rhythm (NSR and other four arrhythmic types from the continuous ECG signals obtained from the MIT-BIH arrhythmia database is proposed. In this configuration, a support vector machine (SVM was used to detect and mark the ECG heartbeats with raw signals and differential signals of a lead ECG. An algorithm based on the extracted markers segments waveforms of Lead II and V1 of the ECG as the pattern classification features. A self-constructing neural fuzzy inference network (SoNFIN was used to classify NSR and four arrhythmia types, including premature ventricular contraction (PVC, premature atrium contraction (PAC, left bundle branch block (LBBB, and right bundle branch block (RBBB. In a real scenario, the classification results show the accuracy achieved is 96.4%. This performance is suitable for a portable ECG monitor system for home care purposes.

  13. Role of His-Purkinje System in Ventricular Arrhythmias%希氏-浦肯野系统和室性心律失常

    Institute of Scientific and Technical Information of China (English)

    周旭; 杨新春

    2011-01-01

    Recently the His-Purkinje system has been found to play an important role in the genesis of ventricular arrhythmias. The anatomic and cellular electrophysiologic complexity of the left ventricular conduction system appears to favor reentrant ventricular tachycardia in both diseased and healthy hearts. Newer discoveries strongly suggest the Purkinje system as the cause of ventricular arrhythmias in patients with short-coupled premature ventricular complexes and in those with catecholaminergic polymorphous ventricular tachycardia. With understanding of mechanisms related to His-Purkinje system and ventricular arrhythmias, many cardiac arrhythmias appears to involve the ventricular specialized conduction system and may be treated with catheter ablation.%近期研究提示希氏-浦肯野系统与室性心律失常的发生关系密切.作为左室的特殊传导组织,希氏-浦肯野系统的解剖与电生理特点,使其在正常或病理情况下易于参与折返型心律失常形成.目前资料提示浦肯野系统病变是短联律间期室性早搏相关心律失常和儿茶酚胺敏感性多形性室性心动过速的原因.随着对希氏-浦肯野系统与室性心律失常关系的认识,导管消融可作为此类心律失常的治疗途径.

  14. Does conversion and prevention of atrial fibrillation enhance survival in patients with left ventricular dysfunction? Evidence from the Danish Investigations of Arrhythmia and Mortality ON Dofetilide/(DIAMOND) study

    DEFF Research Database (Denmark)

    Pedersen, Ole Dyg; Brendorp, Bente; Elming, Hanne;

    2003-01-01

    BACKGROUND: Atrial fibrillation is a common arrhythmia in patients with left ventricular dysfunction associated with increased morbidity and mortality. The present study investigated the potential of dofetilide to restore and maintain sinus rhythm in patients with left ventricular dysfunction......, which might reduce mortality and hospitalizations. METHODS AND RESULTS: In the Danish Investigations of Arrhythmia and Mortality ON Dofetilide (DIAMOND) studies, 506 patients were in atrial fibrillation (AF) or atrial flutter (AFl) at baseline. Over the course of study, cardioversion occurred in 148 (59...

  15. Life-threatening ventricular arrhythmia due to silent coronary artery spasm: usefulness of I-123 metaiodobenzylguanidine scintigraphy for detecting coronary artery spasm in the era of automated external defibrillators: a case report

    OpenAIRE

    Kaku, Bunji; Katsuda, Shoji; Taguchi, Tomio

    2015-01-01

    Introduction Cardiac arrhythmia is sometimes life-threatening, and automated external defibrillators are presently used in some countries. Coronary artery spasm is one of the primary causes of life-threatening arrhythmia. In general, chest symptoms are key indicators of possible coronary artery spasm; however, if chest symptoms are not present, clinicians may not suspect this disease. We encountered a patient who had recovered from ventricular fibrillation treated by using an automated extern...

  16. The risk of life-threatening ventricular arrhythmias in presence of high-intensity endurance exercise along with chronic administration of nandrolone decanoate.

    Science.gov (United States)

    Abdollahi, Farzane; Joukar, Siyavash; Najafipour, Hamid; Karimi, Abdolah; Masumi, Yaser; Binayi, Fateme

    2016-01-01

    Anabolic steroids used to improve muscular strength and performance in athletics. Its long-term consumption may induce cardiovascular adverse effects. We assessed the risk of ventricular arrhythmias in rats which subjected to chronic nandrolone plus high-intensity endurance exercise. Animals were grouped as; control (CTL), exercise (Ex): 8 weeks under exercise, vehicle group (Arach): received arachis oil, and Nan group: received nandrolone decanoate 5 mg/kg twice a week for 8 weeks, Arach+Ex group, and Nan+Ex. Finally, under anesthesia, arrhythmia was induced by infusion of 1.5 μg/0.1 mL/min of aconitine IV and ventricular arrhythmias were recorded for 15 min. Then, animals' hearts were excised and tissue samples were taken. Nandrolone plus exercise had no significant effect on blood pressure but decreased the heart rate (Pventricular fibrillation (VF) frequency and also decreased the VF latency (P<0.05 versus CTL group). Combination of exercise and nandrolone could not recover the decreasing effects of nandrolone on animals weight gain but, it enhanced the heart hypertrophy index (P<0.05). In addition, nandrolone increased the level of hydroxyproline (HYP) and malondialdehyde (MDA) but had not significant effect on glutathione peroxidase of heart. Exercise only prevented the effect of nandrolone on HYP. Nandrolone plus severe exercise increases the risk of VF that cannot be explained only by the changes in redox system. The intensification of cardiac hypertrophy and prolongation of JT interval may be a part of involved mechanisms.

  17. Catheter Ablation to Treat Supraventricular Arrhythmia in Children and Adults With Congenital Heart Disease: What We Know and Where We Are Going

    Science.gov (United States)

    Thomas, Patricia E.; Macicek, Scott L.

    2016-01-01

    Background: Catheter ablation has been used to manage supraventricular arrhythmia in children since 1990. This article reviews the history of catheter ablation used to treat arrhythmia in children and discusses new frontiers in the field. We also address ablation in adult patients with a history of congenital heart disease (CHD) that was diagnosed and initially treated in childhood. Methods: We conducted an evidence-based literature review to gather available data on ablation for supraventricular tachycardia in children and adult patients with CHD. Results: Ablations can be performed safely and effectively in children. Complication rates are higher in children arrhythmia. A paucity of data is available on ablation in adult patients with CHD. Conclusion: Electrophysiology for pediatric and adult patients with CHD is a rapidly growing and progressing field. We benefit from continuous development of ablation techniques for adults with structurally normal hearts and have the unique challenge and responsibility to ensure the safe and effective application of these techniques in the vulnerable population of pediatric and adult patients with CHD. PMID:27660579

  18. Arrhythmia Detection in Pediatric Patients: ECG Quality and Diagnostic Yield of a Patient-Triggered Einthoven Lead-I Event Recorder (Zenicor EKG-2™).

    Science.gov (United States)

    Usadel, Lea; Haverkämper, Guido; Herrmann, Susanne; Löber, Rebekka; Weiss, Katja; Opgen-Rhein, Bernd; Berger, Felix; Will, Joachim C

    2016-03-01

    Symptoms that may be caused by arrhythmia are common in pediatric outpatient departments, though it remains challenging to reveal paroxysmal tachycardia. This investigation evaluated prospectively the quality and diagnostic yield of a newly available handheld patient-activated event recorder (ER) in children. In 226 children (pts) aged 0-17 years with or without congenital heart defects, pacemaker/ICDs or arrhythmia, a lead-I ER ECG was created. ER ECGs were recorded by pressing the patients' thumbs on the device and were analyzed in comparison with a lead-12 ECG, as gold standard. Event recording and data transmission were possible in all cases. ECG quality of the ER showed a high accordance in measuring heart rate (ICC = 0.962), duration of QRS complexes (κ = 0.686), and PR interval (ICC = 0.750) (p detection remained challenging (p = 0.120). 36 % (n = 82) of the pts had heart rhythm disturbances. The ER yielded 92 % sensitivity in diagnosing supraventricular tachycardia plus 77 % sensitivity and 92 % specificity in identifying abnormal ECGs. In children, the application of the tested ER was suitable. ECGs of good quality could be performed and transmitted easily, and also complex arrhythmia analysis was possible. This ER is an excellent diagnostic device for the detection and exclusion of tachycardia in children. PMID:26573815

  19. Comparison of objective methods to classify the pattern of respiratory sinus arrhythmia during mechanical ventilation and paced spontaneous breathing

    International Nuclear Information System (INIS)

    Respiratory sinus arrhythmia (RSA) is a fluctuation of heart period that occurs during a respiratory cycle. It has been suggested that inspiratory heart period acceleration and expiratory deceleration during spontaneous ventilation (henceforth named positive RSA) improve the efficiency of gas exchange compared to the absence or the inversion of such a pattern (negative RSA). During mechanical ventilation (MV), for which maximizing the efficiency of gas exchange is of critical importance, the pattern of RSA is still the object of debate. In order to gain a better insight into this matter, we compared five different methods of RSA classification using the data of five mechanically ventilated piglets. The comparison was repeated using the data of 15 volunteers undergoing a protocol of paced spontaneous breathing, which is expected to result in a positive RSA pattern. The results showed that the agreement between the employed methods is limited, suggesting that the lack of a consensus about the RSA pattern during MV is, at least in part, of methodological origin. However, independently of the method used, the pattern of RSA within the respiratory cycle was not consistent among the subjects and conditions of MV considered. Also, the outcomes showed that even during paced spontaneous breathing a negative RSA pattern might be present, when a low respiratory frequency is imposed

  20. Safe Oral Triiodo-L-Thyronine Therapy Protects from Post-Infarct Cardiac Dysfunction and Arrhythmias without Cardiovascular Adverse Effects.

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    Viswanathan Rajagopalan

    Full Text Available A large body of evidence suggests that thyroid hormones (THs are beneficial for the treatment of cardiovascular disorders. We have shown that 3 days of triiodo-L-thyronine (T3 treatment in myocardial infarction (MI rats increased left ventricular (LV contractility and decreased myocyte apoptosis. However, no clinically translatable protocol is established for T3 treatment of ischemic heart disease. We hypothesized that low-dose oral T3 will offer safe therapeutic benefits in MI.Adult female rats underwent left coronary artery ligation or sham surgeries. T3 (~6 μg/kg/day was available in drinking water ad libitum immediately following MI and continuing for 2 month(s (mo. Compared to vehicle-treated MI, the oral T3-treated MI group at 2 mo had markedly improved anesthetized Magnetic Resonance Imaging-based LV ejection fraction and volumes without significant negative changes in heart rate, serum TH levels or heart weight, indicating safe therapy. Remarkably, T3 decreased the incidence of inducible atrial tachyarrhythmias by 88% and improved remodeling. These were accompanied by restoration of gene expression involving several key pathways including thyroid, ion channels, fibrosis, sympathetic, mitochondria and autophagy.Low-dose oral T3 dramatically improved post-MI cardiac performance, decreased atrial arrhythmias and cardiac remodeling, and reversed many adverse changes in gene expression with no observable negative effects. This study also provides a safe and effective treatment/monitoring protocol that should readily translate to humans.

  1. Effects of Acupuncture at the Yintang and the Chengjiang Acupoints on Cardiac Arrhythmias and Neurocardiogenic Syncope in Emergency First Aid.

    Science.gov (United States)

    Fabrin, Saulo; Soares, Nayara; Pezarezi Yoshimura, Daiana; Hallak Regalo, Simone Cecilio; Donizetti Verri, Edson; de Freitas Vianna, Jacqueline Rodrigues; Gatti Regueiro, Eloisa Maria; Torres da Silva, Josie Resende

    2016-02-01

    This study evaluated the effectiveness of YinTang and ChengJiang acupoints on patients with cardiac arrhythmia and neurocardiogenic syncope in emergency first aid. A 45 year old woman underwent acupuncture. She had a previous history of a valvuloplasty for rheumatic disease and two acute myocardial infarctions, followed by four catheterizations and an angioplasty. Needling of the YinTang acupoint and stimulation of the ChengJiang acupoint through acupressure were performed for 20 minutes soon after syncope and during tachycardia, hypertension, tachypnea, and precordial pain, without any effect on peripheral oxygen saturation (SpO2) or the glycemic index. Data were analyzed comparatively by using the following parameters at rest, during syncope, and at 1 minute and 10 minutes after an emergency acupuncture procedure: blood pressure; heart rate; SpO2; and respiratory rate. We found that acupuncture at YinTang and ChenJiang acupoints induced cardiovascular responses, increased the limits of the body's homeostasis, and normalized the patient's condition in the case of syncope. Acupuncture using a combination of ChengJiang and YinTang acupoints had an immediate effect on the autonomic nervous system and on maintaining homeostasis and energy balance in the body. Although this technique was effective, the patient was still referred to the Emergency Room. PMID:26896074

  2. Associations between respiratory arrhythmia and fundamental frequency of spontaneous crying in preterm and term infants at term-equivalent age.

    Science.gov (United States)

    Shinya, Yuta; Kawai, Masahiko; Niwa, Fusako; Myowa-Yamakoshi, Masako

    2016-09-01

    This study investigated whether lower vagal function in preterm infants is associated with increased fundamental frequency (F0 ; frequency of vocal fold vibration) of their spontaneous cries. We assessed respiratory sinus arrhythmia (RSA) during quiet sleep as a measure of vagal function, and its relationship with the F0 of spontaneous cries in healthy preterm and term infants at term-equivalent age. The results showed that preterm infants have significantly lower RSA, and higher overall F0 than term infants. Moreover, lower RSA was associated with higher overall F0 in preterm infants, whereas higher RSA was positively associated with mean and maximum F0 , and a larger F0 range in term infants. These results suggest that individual differences in vagal function may be associated with the F0 of spontaneous cries via modulation of vocal fold tension in infants at an early developmental stage. © 2016 The Authors. Developmental Psychobiology Published by Wiley Periodicals, Inc. Dev Psychobiol 58:724-733, 2016. PMID:27037599

  3. Does respiratory sinus arrhythmia (RSA) predict anxiety reduction during cognitive behavioral therapy (CBT) for social anxiety disorder (SAD)?

    Science.gov (United States)

    Mathewson, Karen J; Schmidt, Louis A; Miskovic, Vladimir; Santesso, Diane L; Duku, Eric; McCabe, Randi E; Antony, Martin M; Moscovitch, David A

    2013-05-01

    Modifying dysfunctional emotion regulation is an important goal in psychological treatments for social anxiety disorder (SAD). Antecedent-focused strategies learned in cognitive behavioral therapy (CBT), such as cognitive reappraisal, have proven more effective in reducing social anxiety than response-focused strategies, such as expressive suppression. Still, not all patients with SAD respond well to CBT. Medications and physiological factors may also influence the clinical response. The purpose of the present study was to examine the role that these factors play in determining treatment response following CBT for SAD. Using multilevel modeling, we examined associations across four separate laboratory visits between change in self-reported anxiety and indices of reappraisal, suppression, medication status, and resting respiratory sinus arrhythmia (RSA), a proxy measure of self-regulatory capacity, in 23 socially anxious adults during a 12-week program of CBT. Most participants were ultimately classified as responders to CBT (n=15), but in some, anxiety levels remained unchanged (n=8). Medication use explained substantial variance related to individual differences in anxiety among participants. When modeled separately, reappraisal, suppression, and RSA each accounted for significant variance related to anxiety. However, the best-fitting model included reappraisal and RSA. Moreover, RSA reactivity (change in RSA levels over time) was more important for predicting anxiety reduction than were baseline levels of RSA. These findings suggest that reappraisal and parasympathetic responsiveness may be important in reducing anxiety in adults with SAD who respond well to CBT. PMID:23545482

  4. Respiratory Sinus Arrhythmia as an Index of Vagal Activity during Stress in Infants: Respiratory Influences and Their Control

    Science.gov (United States)

    Ritz, Thomas; Bosquet Enlow, Michelle; Schulz, Stefan M.; Kitts, Robert; Staudenmayer, John; Wright, Rosalind J.

    2012-01-01

    Respiratory sinus arrhythmia (RSA) is related to cardiac vagal outflow and the respiratory pattern. Prior infant studies have not systematically examined respiration rate and tidal volume influences on infant RSA or the extent to which infants' breathing is too fast to extract a valid RSA. We therefore monitored cardiac activity, respiration, and physical activity in 23 six-month old infants during a standardized laboratory stressor protocol. On average, 12.6% (range 0–58.2%) of analyzed breaths were too short for RSA extraction. Higher respiration rate was associated with lower RSA amplitude in most infants, and lower tidal volume was associated with lower RSA amplitude in some infants. RSA amplitude corrected for respiration rate and tidal volume influences showed theoretically expected strong reductions during stress, whereas performance of uncorrected RSA was less consistent. We conclude that stress-induced changes of peak-valley RSA and effects of variations in breathing patterns on RSA can be determined for a representative percentage of infant breaths. As expected, breathing substantially affects infant RSA and needs to be considered in studies of infant psychophysiology. PMID:23300753

  5. Respiratory sinus arrhythmia as an index of vagal activity during stress in infants: respiratory influences and their control.

    Directory of Open Access Journals (Sweden)

    Thomas Ritz

    Full Text Available Respiratory sinus arrhythmia (RSA is related to cardiac vagal outflow and the respiratory pattern. Prior infant studies have not systematically examined respiration rate and tidal volume influences on infant RSA or the extent to which infants' breathing is too fast to extract a valid RSA. We therefore monitored cardiac activity, respiration, and physical activity in 23 six-month old infants during a standardized laboratory stressor protocol. On average, 12.6% (range 0-58.2% of analyzed breaths were too short for RSA extraction. Higher respiration rate was associated with lower RSA amplitude in most infants, and lower tidal volume was associated with lower RSA amplitude in some infants. RSA amplitude corrected for respiration rate and tidal volume influences showed theoretically expected strong reductions during stress, whereas performance of uncorrected RSA was less consistent. We conclude that stress-induced changes of peak-valley RSA and effects of variations in breathing patterns on RSA can be determined for a representative percentage of infant breaths. As expected, breathing substantially affects infant RSA and needs to be considered in studies of infant psychophysiology.

  6. Child sex and respiratory sinus arrhythmia reactivity as moderators of the relation between internalizing symptoms and aggression.

    Science.gov (United States)

    Aults, Christopher D; Cooper, Patrick J; Pauletti, Rachel E; Jones, Nancy Aaron; Perry, David G

    2015-12-01

    Previous studies have examined sex differences in physiological responding, including respiratory sinus arrhythmia (RSA) reactivity in response to changing stimulus conditions involving situation specific or gender related cues, in children and adolescents. The present study examined whether RSA reactivity moderates the relation between aggression and internalizing symptoms and whether there are sex differences in this effect. Participants were 82 adolescents (M age = 12.1 years; 44 girls) from the general middle-school population. Peer nominations assessed aggression and internalizing symptoms, and RSA reactivity (defined as change in RSA from baseline to task) was recorded while participants anticipated and responded to an 85 dB signaled white-noise burst. For girls, internalizing symptoms were associated with aggression only if girls showed low RSA reactivity from baseline to task; there was no effect for boys. This association was absent when girls showed high RSA reactivity. Thus, child sex appears to influence not only levels of physiological responding but also relations of physiological responding to comorbidity of adjustment problems.

  7. Prevalence of Cardiac Arrhythmias During and After Pregnancy in Women with Chagas' Disease without Apparent Heart Disease

    Directory of Open Access Journals (Sweden)

    Achá Renato Enrique Sologuren

    2002-01-01

    Full Text Available OBJECTIVE: To evaluate cardiac arrhythmias during and after pregnancy in women with Chagas' disease without apparent heart disease using dynamic electrocardiography. METHODS: Twenty pregnant women with Chagas' disease without apparent heart disease aged 19 to 42 years (26.96 ± 3.6 and a control group of 20 non-chagasic pregnant patients aged 16 to 34 years (22.5 ± 4.8. The patients were submitted to passive hemagglutination and indirect immunofluorescence for the detection of Trypanosoma cruzi evaluation, and electrocardiography, echocardiography and 24-h dynamic electrocardiography. RESULTS: Supraventricular premature depolarizations were observed in 18 (90% patients and ventricular premature depolarization in 11 (55% patients of both groups during pregnancy. After delivery, supraventricular premature depolarizations were present in 13 (60% chagasic patients and in 16 (89.4% control patients (P<=0.05. Ventricular premature depolarization were observed in 9 (45% chagasic patients and 11 (57.8% control patients. CONCLUSION: The prevalence of ventricular premature depolarization was similar for the chagasic and control groups during and after pregnancy. The incidence of supraventricular premature depolarizations was similar in the two groups during pregnancy, while after delivery a predominance was observed in the control group compared to the chagasic group.

  8. Effect of regional differences in cardiac cellular electrophysiology on the stability of ventricular arrhythmias: a computational study

    Science.gov (United States)

    Clayton, Richard H.; Holden, Arun V.

    2003-01-01

    Re-entry is an important mechanism of cardiac arrhythmias. During re-entry a wave of electrical activation repeatedly propagates into recovered tissue, rotating around a rod-like filament. Breakdown of a single re-entrant wave into multiple waves is believed to underlie the transition from ventricular tachycardia to ventricular fibrillation. Several mechanisms of breakup have been identified including the effect of anisotropic conduction in the ventricular wall. Cells in the inner and outer layers of the ventricular wall have different action potential durations (APD), and support re-entrant waves with different periods. The aim of this study was to use a computational approach to study twisting and breakdown in a transmural re-entrant wave spanning these regions, and examine the relative role of this effect and anisotropic conduction. We used a simplified model of action potential conduction in the ventricular wall that we modified so that it supported stable re-entry in an anisotropic model with uniform APD. We first examined the effect of regional differences on breakdown in an isotropic model with transmural differences in APD, and found that twisting of the re-entrant filament resulted in buckling and breakdown during the second cycle of re-entry. We found that breakdown was amplified in the anisotropic model, resulting in complex activation in the region of longest APD. This study shows that regional differences in cardiac electrophysiology are a potentially important mechanism for destabilizing re-entry and may act synergistically with other mechanisms to mediate the transition from ventricular tachycardia to ventricular fibrillation.

  9. Spatial memory and long-term object recognition are impaired by circadian arrhythmia and restored by the GABAAAntagonist pentylenetetrazole.

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    Norman F Ruby

    Full Text Available Performance on many memory tests varies across the day and is severely impaired by disruptions in circadian timing. We developed a noninvasive method to permanently eliminate circadian rhythms in Siberian hamsters (Phodopus sungorus [corrected] so that we could investigate the contribution of the circadian system to learning and memory in animals that are neurologically and genetically intact. Male and female adult hamsters were rendered arrhythmic by a disruptive phase shift protocol that eliminates cycling of clock genes within the suprachiasmatic nucleus (SCN, but preserves sleep architecture. These arrhythmic animals have deficits in spatial working memory and in long-term object recognition memory. In a T-maze, rhythmic control hamsters exhibited spontaneous alternation behavior late in the day and at night, but made random arm choices early in the day. By contrast, arrhythmic animals made only random arm choices at all time points. Control animals readily discriminated novel objects from familiar ones, whereas arrhythmic hamsters could not. Since the SCN is primarily a GABAergic nucleus, we hypothesized that an arrhythmic SCN could interfere with memory by increasing inhibition in hippocampal circuits. To evaluate this possibility, we administered the GABAA antagonist pentylenetetrazole (PTZ; 0.3 or 1.0 mg/kg/day to arrhythmic hamsters for 10 days, which is a regimen previously shown to produce long-term improvements in hippocampal physiology and behavior in Ts65Dn (Down syndrome mice. PTZ restored long-term object recognition and spatial working memory for at least 30 days after drug treatment without restoring circadian rhythms. PTZ did not augment memory in control (entrained animals, but did increase their activity during the memory tests. Our findings support the hypothesis that circadian arrhythmia impairs declarative memory by increasing the relative influence of GABAergic inhibition in the hippocampus.

  10. Spatial memory and long-term object recognition are impaired by circadian arrhythmia and restored by the GABAAAntagonist pentylenetetrazole.

    Science.gov (United States)

    Ruby, Norman F; Fernandez, Fabian; Garrett, Alex; Klima, Jessy; Zhang, Pei; Sapolsky, Robert; Heller, H Craig

    2013-01-01

    Performance on many memory tests varies across the day and is severely impaired by disruptions in circadian timing. We developed a noninvasive method to permanently eliminate circadian rhythms in Siberian hamsters (Phodopus sungorus) [corrected] so that we could investigate the contribution of the circadian system to learning and memory in animals that are neurologically and genetically intact. Male and female adult hamsters were rendered arrhythmic by a disruptive phase shift protocol that eliminates cycling of clock genes within the suprachiasmatic nucleus (SCN), but preserves sleep architecture. These arrhythmic animals have deficits in spatial working memory and in long-term object recognition memory. In a T-maze, rhythmic control hamsters exhibited spontaneous alternation behavior late in the day and at night, but made random arm choices early in the day. By contrast, arrhythmic animals made only random arm choices at all time points. Control animals readily discriminated novel objects from familiar ones, whereas arrhythmic hamsters could not. Since the SCN is primarily a GABAergic nucleus, we hypothesized that an arrhythmic SCN could interfere with memory by increasing inhibition in hippocampal circuits. To evaluate this possibility, we administered the GABAA antagonist pentylenetetrazole (PTZ; 0.3 or 1.0 mg/kg/day) to arrhythmic hamsters for 10 days, which is a regimen previously shown to produce long-term improvements in hippocampal physiology and behavior in Ts65Dn (Down syndrome) mice. PTZ restored long-term object recognition and spatial working memory for at least 30 days after drug treatment without restoring circadian rhythms. PTZ did not augment memory in control (entrained) animals, but did increase their activity during the memory tests. Our findings support the hypothesis that circadian arrhythmia impairs declarative memory by increasing the relative influence of GABAergic inhibition in the hippocampus.

  11. Drug-induced Inhibition and Trafficking Disruption of ion Channels: Pathogenesis of QT Abnormalities and Drug-induced Fatal Arrhythmias.

    Science.gov (United States)

    Cubeddu, Luigi X

    2016-01-01

    Risk of severe and fatal ventricular arrhythmias, presenting as Torsade de Pointes (TdP), is increased in congenital and acquired forms of long QT syndromes (LQTS). Drug-induced inhibition of K+ currents, IKs, IKr, IK1, and/or Ito, delay repolarization, prolong QT, and increase the risk of TdP. Drug-induced interference with IKr is the most common cause of acquired LQTS/TdP. Multiple drugs bind to KNCH2-hERG-K+ channels affecting IKr, including antiarrythmics, antibiotics, antivirals, azole-antifungals, antimalarials, anticancer, antiemetics, prokinetics, antipsychotics, and antidepressants. Azithromycin has been recently added to this list. In addition to direct channel inhibition, some drugs interfere with the traffic of channels from the endoplasmic reticulum to the cell membrane, decreasing mature channel membrane density; e.g., pentamidine, geldalamicin, arsenic trioxide, digoxin, and probucol. Other drugs, such as ketoconazole, fluoxetine, norfluoxetine, citalopram, escitalopram, donepezil, tamoxifen, endoxifen, atazanavir, and roxitromycin, induce both direct channel inhibition and impaired channel trafficking. Although many drugs prolong the QT interval, TdP is a rare event. The following conditions increase the risk of drug-induced TdP: a) Disease states/electrolyte levels (heart failure, structural cardiac disease, bradycardia, hypokalemia); b) Pharmacogenomic variables (presence of congenital LQTS, subclinical ion-channel mutations, history of or having a relative with history of drug-induced long QT/TdP); c) Pharmacodynamic and kinetic factors (high doses, women, elderly, metabolism inhibitors, combining two or more QT prolonging drugs, drugs that prolong the QT and increase QT dispersion, and drugs with multiple actions on ion channels). Because most of these conditions are preventable, careful evaluation of risk factors and increased knowledge of drug use associated with repolarization abnormalities are strongly recommended. PMID:26926294

  12. Weather-induced ischemia and arrhythmia in patients undergoing cardiac rehabilitation: another difference between men and women

    Science.gov (United States)

    Schneider, Alexandra; Schuh, Angela; Maetzel, Friedrich-Karl; Rückerl, Regina; Breitner, Susanne; Peters, Annette

    2008-07-01

    Given the accumulating evidence that people with underlying heart disease are a particularly vulnerable group for triggers like changing meteorological parameters, the objective of this longitudinal study was to analyze the influence of weather parameters on blood pressure, arrhythmia and ischemia in cardiovascular patients. A panel study with repeated measurements was conducted in a rehabilitation clinic in Timmendorfer Strand (Baltic Sea, Germany) with 872 cardiovascular patients. Heart rate, blood pressure and electrocardiography changes were measured during repeated bicycle ergometries. Generalized Estimating Equations were used for regression analyses of immediate, delayed and cumulative influences of the daily measured meteorological data. For men, a decrease in air temperature and in water vapor pressure doubled the risk of ST-segment depression during ergometry [odds ratio (OR) for 1 day delay: 1.88 (1.24; 2.83) for air temperature] with a delay of 1-2 days. For women, an increase of their heart rate before the start of the ergometry [same day: 4.36 beats/min (0.99; 7.74) for air temperature] and a 2- to 3-fold higher risk for ventricular ectopic beats [1 day delay: OR 2.43 (1.17; 5.05) for air temperature] was observed with an increase in temperature and water vapor pressure in almost all analyzed time-windows. The study indicates that meteorological parameters can induce changes in heart function which may lead to adverse cardiovascular events especially in susceptible, diseased individuals. The observed effect on ST-segment depression could be a link between the association of weather changes and cardiovascular morbidity and mortality.

  13. A proton leak current through the cardiac sodium channel is linked to mixed arrhythmia and the dilated cardiomyopathy phenotype.

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    Pascal Gosselin-Badaroudine

    Full Text Available Cardiac Na(+ channels encoded by the SCN5A gene are essential for initiating heart beats and maintaining a regular heart rhythm. Mutations in these channels have recently been associated with atrial fibrillation, ventricular arrhythmias, conduction disorders, and dilated cardiomyopathy (DCM.We investigated a young male patient with a mixed phenotype composed of documented conduction disorder, atrial flutter, and ventricular tachycardia associated with DCM. Further family screening revealed DCM in the patient's mother and sister and in three of the mother's sisters. Because of the complex clinical phenotypes, we screened SCN5A and identified a novel mutation, R219H, which is located on a highly conserved region on the fourth helix of the voltage sensor domain of Na(v1.5. Three family members with DCM carried the R219H mutation.The wild-type (WT and mutant Na(+ channels were expressed in a heterologous expression system, and intracellular pH (pHi was measured using a pH-sensitive electrode. The biophysical characterization of the mutant channel revealed an unexpected selective proton leak with no effect on its biophysical properties. The H(+ leak through the mutated Na(v1.5 channel was not related to the Na(+ permeation pathway but occurred through an alternative pore, most probably a proton wire on the voltage sensor domain.We propose that acidification of cardiac myocytes and/or downstream events may cause the DCM phenotype and other electrical problems in affected family members. The identification of this clinically significant H(+ leak may lead to the development of more targeted treatments.

  14. Clinical Observation and Nursing care on Arrhythmia of Degenerative Heart Valvular Desease%老年退行性心脏瓣膜病心律失常的临床观察与护理

    Institute of Scientific and Technical Information of China (English)

    施惠碧

    2011-01-01

    目的:探讨SDHVD心律失常的护理对策.方法:对75例SDHVD住院患者进行严密心电监护,观察心率的频率、节律、类型、时间,患者的活动状态并做好护理.结果:在75例SDHVD患者中出现心律失常46例,给予抗心律失常药物治疗和采取有效的护理措施,均好转出院.结论:SDHVD发病隐袭,缺乏特异性的临床表现,目前尚无有效的药物治疗,心律失常是SDHVD最常见的并发症,临床观察护理尤为重要,可减少恶性心律失常的发生,为诊治提供依据.%Objective To evaluate the nursing countermeasure of SDHVD on arrhythmia. Methods Close ECG monitoring were given to 75 SDHVD inpatients,and the parameters such as heart rate,rhythm, type, duration of arrhythmia as well as activity situation of patients were observed, and carefully nursing were provided at the same time. Rusults We found that arrhythmia occurred in46 cases of 75 SDHVD patients,and they were all discharged from hospital with improvement after treatment with anti - arrhythmia medication and effective nursing measure. Conclusions Until now, no treatment has shown efficacy on SDHVD because of insidious onset of the desease and lack of special clinical manifestations. Since arrhythmia is the most common complication of SDHVD,we think clinical observation and nursing care on arrhythmia would be very important to reduce the malignant arrhythmia occurrence ,provide basis for diagnosis and remedy of SDHVD at the same time.

  15. The risk of life-threatening ventricular arrhythmias in presence of high-intensity endurance exercise along with chronic administration of nandrolone decanoate.

    Science.gov (United States)

    Abdollahi, Farzane; Joukar, Siyavash; Najafipour, Hamid; Karimi, Abdolah; Masumi, Yaser; Binayi, Fateme

    2016-01-01

    Anabolic steroids used to improve muscular strength and performance in athletics. Its long-term consumption may induce cardiovascular adverse effects. We assessed the risk of ventricular arrhythmias in rats which subjected to chronic nandrolone plus high-intensity endurance exercise. Animals were grouped as; control (CTL), exercise (Ex): 8 weeks under exercise, vehicle group (Arach): received arachis oil, and Nan group: received nandrolone decanoate 5 mg/kg twice a week for 8 weeks, Arach+Ex group, and Nan+Ex. Finally, under anesthesia, arrhythmia was induced by infusion of 1.5 μg/0.1 mL/min of aconitine IV and ventricular arrhythmias were recorded for 15 min. Then, animals' hearts were excised and tissue samples were taken. Nandrolone plus exercise had no significant effect on blood pressure but decreased the heart rate (P<0.01) and increased the RR (P<0.01) and JT intervals (P<0.05) of electrocardiogram. Nandrolone+exercise significantly increased the ventricular fibrillation (VF) frequency and also decreased the VF latency (P<0.05 versus CTL group). Combination of exercise and nandrolone could not recover the decreasing effects of nandrolone on animals weight gain but, it enhanced the heart hypertrophy index (P<0.05). In addition, nandrolone increased the level of hydroxyproline (HYP) and malondialdehyde (MDA) but had not significant effect on glutathione peroxidase of heart. Exercise only prevented the effect of nandrolone on HYP. Nandrolone plus severe exercise increases the risk of VF that cannot be explained only by the changes in redox system. The intensification of cardiac hypertrophy and prolongation of JT interval may be a part of involved mechanisms. PMID:26686897

  16. Long QT, alteration of calcium-phosphate product, prevalence of ventricular arrhythmias and sudden death in peritoneal dialysis patients: a Holter study

    Directory of Open Access Journals (Sweden)

    Pierluigi Di Loreto

    2013-03-01

    Full Text Available Materials and methods We studied 79 patients on peritoneal dialysis. Each underwent 24-h electrocardiography (Holter monitoring and measurement of the rate-corrected QT interval (QTc. We analyzed the correlation between QTc and plasma levels of Ca++, PO4−, K+, Na+, Mg++, and parathyroid hormone (PTH. Results The mean QTc was 0.445 ± 0.04 s. In 55 patients, the QTc was prolonged (> 0.45 s. Mean laboratory values for the group were: PTH 344 ± 25 pg/mL, Ca++ 9.27 ± 0.11 mg/dL, PO4− 5.5 ± 1.5 mg/dL, Na+ 139.6 ± 3.4 mmol/L, K+ 4.04 ± 0.64 mmol/L, and Mg++ 2.52 ± 0.43 mg/dL. Holter monitoring revealed complex premature ventricular contractions in 44 patients, monomorphic premature ventricular contractions in 16, and nonsustained ventricular tachycardia (NSVT in 10. The QTc was significantly correlated with plasma levels of PO4− (r = 0.045, p < 0.05, PTH (r = 0.077, p < 0.02, and Ca++ (r = 0.076, p < 0.02. Eleven patients had Lown class 4a or 4b ventricular arrhythmias, and their mean QTc was 465 ± 0.02 ms. Ten had NSVT and their QTc was 464 ± 0.03 ms. Eleven patients died suddenly (mean QTc 465 ± 0.03 ms; all 11 had either NSTV or Lown class 4 ventricular arrhythmias. Conclusions Long QTc seems to be associated with an increased prevalence of ventricular arrhythmias that may be the cause of sudden cardiac death.

  17. Inhalation of diluted diesel engine emission impacts heart rate variability and arrhythmia occurrence in a rat model of chronic ischemic heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Anselme, Frederic [Rouen University Hospital, Service de Cardiologie, Rouen (France); Loriot, Stephane; Henry, Jean-Paul; Thuillez, Christian; Morin, Jean-Paul [University of Rouen France, INSERM U644, School of Medicine-Pharmacy, Rouen, Cedex (France); Dionnet, Frederic [Centre d' Etudes et de Recherches Technologiques en Aerothermique et Moteurs, Saint Etienne du Rouvray (France); Napoleoni, Jean-Gerard [EMKA Technologies, Paris (France)

    2007-04-15

    Both increase in cardiac arrhythmia incidence and decrease in heart rate variability (HRV) have been described following human and experimental animal exposures to air pollutants. However, the potential causal relationship between these two factors remains unclear. Incidence of ventricular arrhythmia and HRV were evaluated during and after a 3 h period of Diesel engine exhaust exposure in ten healthy and ten chronic ischemic heart failure (CHF, 3 months after coronary ligation) Wistar rats using implantable ECG telemetry. Air pollutants were delivered to specifically designed whole body individual exposure chambers at particulate matter concentrations similar to those measured inside cabins of cars inserted in congested urban traffic. Recordings were obtained from unrestraint and unsedated vigil rats. Immediate decrease in RMSSD was observed in both healthy (6.64 {+-} 2.62 vs. 4.89 {+-} 1.67 ms, P < 0.05) and CHF rats (8.01 {+-} 0.89 vs. 6.6 {+-} 1.37 ms, P < 0.05) following exposure. An immediate 200-500% increase in ventricular premature beats was observed in CHF rats only. Whereas HRV progressively returned to baseline values within 2.5 h after exposure start, the proarrhythmic effect persisted as late as 5 h after exposure termination in CHF rats. Persistence of ventricular proarrhythmic effects after HRV normalization suggests that HRV reduction is not the mechanism of cardiac arrhythmias in this model. Our methodological approach, closely reflecting the real clinical situations, appeared to be a unique tool to provide further insight into the pathophysiological mechanisms of traffic related airborne pollution health impact. (orig.)

  18. Chiropractic Treatment of Cervicogenic Arrhythmia in 34 Cases%整脊法治疗颈源性心律失常34例

    Institute of Scientific and Technical Information of China (English)

    胡青林

    2013-01-01

      目的:观察整脊法治疗颈源性心律失常的临床疗效.方法:将70例颈源性心律失常患者随机分为治疗组和对照组,治疗组采用定点旋转复位法治疗,对照组采用常规推拿治疗,两各疗程后观察疗效.结果:治疗组总有效率94.1%,对照组总有效率75.0%,治疗组高于对照组(P<0.05).结论:整脊法治疗颈源性心律失常操作安全,疗效显著,值得推广.%Objective: To observe the clinical effect of chiropractic therapy with cervicogenic arrhythmia. Methods: 70 cases of cervi-cogenic arrhythmia patients were randomly divided into treatment group and control group, treatment group were treated with Fixed-point rotation reduction method, while the control group adopted conventional massage therapy, and observed curative effect after two courses. Results: The total effective rate of treatment group was 94.1%, that of control group was 75%, the treatment group was better than treatment group (P<0.05). Conclusion: Chiropractic treatment of cervicogenic arrhythmia is operational safety and obvious curative effect, which is worth if promotion.

  19. 迷走神经在心律失常发生中的研究进展%Role of vagal nerve in cardiac arrhythmia

    Institute of Scientific and Technical Information of China (English)

    冯璇; 臧伟进; 周筠

    2012-01-01

    作为遗传性心律失常之一的长QT综合征(LQTS),现已发现有12型,其中在中国以LQT2为常见,可诱发尖端扭转型室性心动过速及室颤,临床上以反复发作的晕厥及常导致的猝死为特征.自主神经通过释放神经递质作用于受体调节离子通道,从而对某些心律失常起到一定的作用,而迷走神经通过直接或间接作用对多种心律失常具有一定的保护作用.本文主要对LQT2的研究进展、迷走神经与LQT2的关系以及其在心律失常中发挥的作用作一综述.%As one of the familial abnormalities of cardiac rhythm, Long QT syndrome ( LQTS) has been found in 12 different genes. LQT2 is one of the most common LQTS in China, which can lead to Torsade de Points (TdP) and ventricular fibrillation ( VF). Clinically it is characterized by recurrent syncope and sudden cardiac death. The autonomic nervous system plays a vital role in some cases of cardiac arrhythmia through the release of neurotransmitter to regulate ion channel. Recently, studies have shown that vagal nerve can reduce the occurrence of certain kinds of cardiac arrhythmia and may play an important role in maintaining normal cardiac rhythm and rate. This paper mainly reviews the recent advances of LQT2, the complex relationship between vagal nerve and LQT2, and the role of vagal nerve in cardiac arrhythmia.

  20. The effect of acute simvastatin administration on the severity of arrhythmias resulting from ischaemia and reperfusion in the canine: Is there a role for nitric oxide?

    Science.gov (United States)

    Kisvári, Gábor; Kovács, Mária; Gardi, János; Seprényi, György; Kaszaki, József; Végh, Ágnes

    2014-06-01

    The present study has examined the effects and the possible mechanisms of a single dose of simvastatin on the severity of arrhythmias resulting from a 25min occlusion and reperfusion of the left anterior descending coronary artery in anaesthetized (chloralose and urethane) dogs. The control animals (n=16) were given the solvent of simvastatin by slow (over 5min) intracoronary (ic.) injection just prior to the occlusion. Twenty-six dogs were treated with simvastatin (0.1mg/kg) by the same route, both in the absence (n=15) and in the presence (n=11) of l-NAME. This latter was administered (5mg/kg, ic.) either alone (n=12) or 10min before the simvastatin treatment. The severity of ischaemia (epicardial ST-segment, inhomogeneity) and ventricular arrhythmias (ventricular premature beats [VPBs], ventricular tachycardia [VT] and fibrillation [VF]), plasma nitrite/nitrate levels, myocardial superoxide production and eNOS activity were assessed. Compared with controls simvastatin significantly reduced the number of VPBs (289±34vs. 94±25) and the episodes of VT (5.6±1.3vs. 0.3±0.2), the incidence of VT (88% vs. 20%) and VF (56% vs. 0%) during occlusion and increased survival (0% vs. 33%) on reperfusion. There were also less marked ischaemic changes in the simvastatin-treated dogs than in the controls. Simvastatin preserved eNOS activity and nitric oxide (NO) bioavailability during occlusion and attenuated superoxide production following reperfusion. All these effects of simvastatin (except for the protection against VF) were reversed by l-NAME. We conclude that simvastatin given just prior to ischaemia/reperfusion reduces the severity of arrhythmias. This effect involves both NO-dependent and NO-independent mechanisms. PMID:24685640

  1. TITERS OF ANTIBODIES TO Β1-ADRENOCEPTOR AND M2 CHOLINERGIC RECEPTORS IN PATIENTS WITH VENTRICULAR ARRHYTHMIAS WITHOUT AN ORGANIC CARDIOVASCULAR DISEASE AND THEIR POSSIBLE CLINICAL SIGNIFICANCE

    Directory of Open Access Journals (Sweden)

    M. M. Rogova

    2012-01-01

    Full Text Available Aim. To identify the most promising epitopes that simulate various sites β1-adrenergic and M2-cholinergic receptors, and to evaluate their possible contribution to the development and maintenance of cardiac arrhythmias, particularly idiopathic ventricular arrhythmia. Material and methods. Patients with ventricular arrhythmias without organic cardiovascular disease (the study group; n=70 were included in the study. The control group consisted of 20 healthy volunteers. Evaluation of levels of antibodies to antigenic determinants, modeling various sites β1-adrenergic and M2-cholinergic performed in all patients. Causal treatment with clarithromycin and valacyclovir performed in part of patients. Results. Antibodies to different peptide sequences of β1-adrenergic and M2-cholinergic receptors have been identified in 25% of main group patients. A direct correlation between the frequency of episodes of ventricular tachycardia and IgG levels to MRI-MRIV (p=0.02 revealed. Increase in titre of antibodies to β1-adrenoceptors, to a peptide sequence β8 (p=0.02, and lower titers of antibodies to the M2 acetylcholine receptor — chimera MRI-MRIV IgM (p=0.06 and ARI-MRIV IgM (p=0.07 were observed when assessing the efficacy of the therapy in the causal dynamics in the group of "untreated" patients. IgG titer reduction of ARI-MRIV (p=0.02, which is 4 times out of 10 with reduction of ventricular ectopic activity , recorded after valacyclovir therapy. Clarithromycin therapy on the level of antibodies exerted no significant effect. Conclusion. Possible involvement of antibodies to β1-adrenoceptor and M2-cholinergic receptors in the development of idiopathic ventricular arrhythmias demonstrated. The relationship between the frequency of episodes of ventricular tachycardia and levels of antibody titers to M2-cholinergic receptors found. Attempt of causal treatment, depending on the possible mechanisms of the autoimmune process is executed. Further studies to

  2. Effect of verapamil on ischemia and ventricular arrhythmias after an acute myocardial infarction: prognostic implications. The Danish Verapamil Infarction Trial II Study Group

    DEFF Research Database (Denmark)

    Vaage-Nilsen, M; Rasmussen, Verner; Hansen, J F;

    1991-01-01

    for 24-48 h at 1 week, i.e., before randomization to long-term treatment with placebo or verapamil, and after 1 month and about 1 year of study treatment. Ischemia: 18% of the patients had transient ST-segment deviation before randomization; 24% of the placebo- and 8% of the verapamil-treated patients (p......This article is a review of presented subsets of the Danish Verapamil Infarction Trial II (DAVIT II) regarding the effect of verapamil on postinfarction ischemia, ventricular arrhythmias, and heart rate (HR), and the prognostic implications of these findings. Patients underwent Holter monitoring...

  3. Growth factor-induced mobilization of cardiac progenitor cells reduces the risk of arrhythmias, in a rat model of chronic myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Leonardo Bocchi

    Full Text Available Heart repair by stem cell treatment may involve life-threatening arrhythmias. Cardiac progenitor cells (CPCs appear best suited for reconstituting lost myocardium without posing arrhythmic risks, being commissioned towards cardiac phenotype. In this study we tested the hypothesis that mobilization of CPCs through locally delivered Hepatocyte Growth Factor and Insulin-Like Growth Factor-1 to heal chronic myocardial infarction (MI, lowers the proneness to arrhythmias. We used 133 adult male Wistar rats either with one-month old MI and treated with growth factors (GFs, n = 60 or vehicle (V, n = 55, or sham operated (n = 18. In selected groups of animals, prior to and two weeks after GF/V delivery, we evaluated stress-induced ventricular arrhythmias by telemetry-ECG, cardiac mechanics by echocardiography, and ventricular excitability, conduction velocity and refractoriness by epicardial multiple-lead recording. Invasive hemodynamic measurements were performed before sacrifice and eventually the hearts were subjected to anatomical, morphometric, immunohistochemical, and molecular biology analyses. When compared with untreated MI, GFs decreased stress-induced arrhythmias and concurrently prolonged the effective refractory period (ERP without affecting neither the duration of ventricular repolarization, as suggested by measurements of QTc interval and mRNA levels for K-channel α-subunits Kv4.2 and Kv4.3, nor the dispersion of refractoriness. Further, markers of cardiomyocyte reactive hypertrophy, including mRNA levels for K-channel α-subunit Kv1.4 and β-subunit KChIP2, interstitial fibrosis and negative structural remodeling were significantly reduced in peri-infarcted/remote ventricular myocardium. Finally, analyses of BrdU incorporation and distribution of connexin43 and N-cadherin indicated that cytokines generated new vessels and electromechanically-connected myocytes and abolished the correlation of infarct size with deterioration

  4. Arrhythmia Identification with Two-Lead Electrocardiograms Using Artificial Neural Networks and Support Vector Machines for a Portable ECG Monitor System

    OpenAIRE

    Liu, Shing-Hong; Cheng, Da-Chuan; Lin, Chih-Ming

    2013-01-01

    An automatic configuration that can detect the position of R-waves, classify the normal sinus rhythm (NSR) and other four arrhythmic types from the continuous ECG signals obtained from the MIT-BIH arrhythmia database is proposed. In this configuration, a support vector machine (SVM) was used to detect and mark the ECG heartbeats with raw signals and differential signals of a lead ECG. An algorithm based on the extracted markers segments waveforms of Lead II and V1 of the ECG as the pattern cl...

  5. Impact of potentially lethal ventricular arrhythmias on long-term outcome in patients with chronic heart failure

    Institute of Scientific and Technical Information of China (English)

    LIU Ye-hong; SHEN Wei-feng; SU Jing-ying; WANG Lin-jie; LI Jin-ping; ZHOU Qing-fen; GAN Qian; CHAI Xi-chen; DAI Li-ying; ZHANG Feng-ru

    2012-01-01

    Background Potentially lethal ventricular arrhythmias (PLVAs) occur frequently in survivors after acute myocardial infarction and are increasingly recognized in other forms of structural heart diseases.This study investigated the prevalence and prognostic significance of PLVAs in patients with chronic heart failure (CHF).Methods Data concerning demographics,etiology of heart failure,NYHA functional class,biochemical variables,electrocardiographic and echocardiographic findings,and medical treatments were collected by reviewing hospital medical records from 1080 patients with NYHA Ⅱ-Ⅳ and a left ventricular (LV) ejection fraction ≤45%.PLVAs were defined as multi-focal ventricular ectopy (>30 beats/h on Holter monitoring),bursts of ventricular premature beats,and nonsustained ventricular tachycardia.All-cause mortality,sudden death,and rehospitalization due to worsening heart failure,or cardiac transplantation during 5-year follow-up after discharge were recorded.Results The occurrence rate of PLVAs in CHF was 30.2%,and increased with age; 23.4% in patients <45 years old,27.8% in those between 45-65 years old,and 33.5% in patients >65 years old (P=0.033).Patients with PLVAs had larger LV size and lower ejection fraction (both P <0.01) and higher all-cause mortality (P=0.014) during 5-year follow-up than those without PLVAs.Age (OR 1.041,95% Cl 1.004-1.079,P=0.03) and LV end-diastolic dimension (OR 1.068,95% Cl 1.013-1.126,P=0.015) independently predicted the occurrence of PLVAs.And PLVA was an independent factor for all-cause mortality (RR 1.702,95% Cl 1.017-2.848,P=0.031) and sudden death (RR 1.937,95% CI 1.068-3.516,P=0.030) in patients with CHF.Conclusion PLVAs are common and exert a negative impact on Iona-term clinical outcome in patients with CHF.

  6. Genetically engineered excitable cardiac myofibroblasts coupled to cardiomyocytes rescue normal propagation and reduce arrhythmia complexity in heterocellular monolayers.

    Directory of Open Access Journals (Sweden)

    Luqia Hou

    Full Text Available RATIONALE AND OBJECTIVE: The use of genetic engineering of unexcitable cells to enable expression of gap junctions and inward rectifier potassium channels has suggested that cell therapies aimed at establishing electrical coupling of unexcitable donor cells to host cardiomyocytes may be arrhythmogenic. Whether similar considerations apply when the donor cells are electrically excitable has not been investigated. Here we tested the hypothesis that adenoviral transfer of genes coding Kir2.1 (I(K1, Na(V1.5 (I(Na and connexin-43 (Cx43 proteins into neonatal rat ventricular myofibroblasts (NRVF will convert them into fully excitable cells, rescue rapid conduction velocity (CV and reduce the incidence of complex reentry arrhythmias in an in vitro model. METHODS AND RESULTS: We used adenoviral (Ad- constructs encoding Kir2.1, Na(V1.5 and Cx43 in NRVF. In single NRVF, Ad-Kir2.1 or Ad-Na(V1.5 infection enabled us to regulate the densities of I(K1 and I(Na, respectively. At varying MOI ratios of 10/10, 5/10 and 5/20, NRVF co-infected with Ad-Kir2.1+ Na(V1.5 were hyperpolarized and generated action potentials (APs with upstroke velocities >100 V/s. However, when forming monolayers only the addition of Ad-Cx43 made the excitable NRVF capable of conducting electrical impulses (CV = 20.71±0.79 cm/s. When genetically engineered excitable NRVF overexpressing Kir2.1, Na(V1.5 and Cx43 were used to replace normal NRVF in heterocellular monolayers that included neonatal rat ventricular myocytes (NRVM, CV was significantly increased (27.59±0.76 cm/s vs. 21.18±0.65 cm/s, p<0.05, reaching values similar to those of pure myocytes monolayers (27.27±0.72 cm/s. Moreover, during reentry, propagation was faster and more organized, with a significantly lower number of wavebreaks in heterocellular monolayers formed by excitable compared with unexcitable NRVF. CONCLUSION: Viral transfer of genes coding Kir2.1, Na(V1.5 and Cx43 to cardiac myofibroblasts endows them with

  7. Multistep ion channel remodeling and lethal arrhythmia precede heart failure in a mouse model of inherited dilated cardiomyopathy.

    Directory of Open Access Journals (Sweden)

    Takeshi Suzuki

    Full Text Available BACKGROUND: Patients with inherited dilated cardiomyopathy (DCM frequently die with severe heart failure (HF or die suddenly with arrhythmias, although these symptoms are not always observed at birth. It remains unclear how and when HF and arrhythmogenic changes develop in these DCM mutation carriers. In order to address this issue, properties of the myocardium and underlying gene expressions were studied using a knock-in mouse model of human inherited DCM caused by a deletion mutation ΔK210 in cardiac troponinT. METHODOLOGY/PRINCIPAL FINDINGS: By 1 month, DCM mice had already enlarged hearts, but showed no symptoms of HF and a much lower mortality than at 2 months or later. At around 2 months, some would die suddenly with no clear symptoms of HF, whereas at 3 months, many of the survivors showed evident symptoms of HF. In isolated left ventricular myocardium (LV from 2 month-mice, spontaneous activity frequently occurred and action potential duration (APD was prolonged. Transient outward (I(to and ultrarapid delayed rectifier K(+ (I(Kur currents were significantly reduced in DCM myocytes. Correspondingly, down-regulation of Kv4.2, Kv1.5 and KChIP2 was evident in mRNA and protein levels. In LVs at 3-months, more frequent spontaneous activity, greater prolongation of APD and further down-regulation in above K(+ channels were observed. At 1 month, in contrast, infrequent spontaneous activity and down-regulation of Kv4.2, but not Kv1.5 or KChIP2, were observed. CONCLUSIONS/SIGNIFICANCE: Our results suggest that at least three steps of electrical remodeling occur in the hearts of DCM model mice, and that the combined down-regulation of Kv4.2, Kv1.5 and KChIP2 prior to the onset of HF may play an important role in the premature sudden death in this DCM model. DCM mice at 1 month or before, on the contrary, are associated with low risk of death in spite of inborn disorder and enlarged heart.

  8. Medications for Arrhythmia

    Science.gov (United States)

    ... a one-stop, easy-to-use set of online tracking tools for medications, blood pressure, cholesterol, blood glucose, ... a one-stop, easy-to-use set of online tracking tools for medications, blood pressure, cholesterol, blood glucose, ...

  9. How Are Arrhythmias Diagnosed?

    Science.gov (United States)

    ... and beat fast. The heart tests done during stress testing may include nuclear heart scanning , echo, and positron emission tomography (PET) scanning of the heart. Electrophysiology study (EPS). This ...

  10. Platelets and cardiac arrhythmia

    Directory of Open Access Journals (Sweden)

    Jonas S De Jong

    2010-12-01

    Full Text Available Sudden cardiac death remains one of the most prevalent modes of death in industrialized countries, and myocardial ischemia due to thrombotic coronary occlusion is its primary cause. The role of platelets in the occurrence of SCD extends beyond coronary flow impairment by clot formation. Here we review the substances released by platelets during clot formation and their arrhythmic properties. Platelet products are released from three types of platelet granules: dense core granules, alpha-granules, and platelet lysosomes. The physiologic properties of dense granule products are of special interest as a potential source of arrhythmic substances. They are released readily upon activation and contain high concentrations of serotonin, histamine, purines, pyrimidines, and ions such as calcium and magnesium. Potential arrhythmic mechanisms of these substances, e.g. serotonin and high energy phosphates, include induction of coronary constriction, calcium overloading, and induction of delayed after-depolarizations. Alpha-granules produce thromboxanes and other arachidonic acid products with many potential arrhythmic effects mediated by interference with cardiac sodium, calcium and potassium channels. Alpha-granules also contain hundreds of proteins that could potentially serve as ligands to receptors on cardiomyocytes. Lysosomal products probably do not have an important arrhythmic effect. Platelet products and ischemia can induce coronary permeability, thereby enhancing interaction with surrounding cardiomyocytes. Antiplatelet therapy is known to improve survival after myocardial infarction. Although an important part of this effect results from prevention of coronary clot formation, there is evidence to suggest that antiplatelet therapy also induces anti-arrhythmic effects during ischemia by preventing the release of platelet activation products.

  11. Living with an Arrhythmia

    Science.gov (United States)

    ... disease. Keep your heart healthy by following a healthy diet. A healthy diet includes a variety of fruits and vegetables. It ... products, nuts, seeds, and beans and peas. A healthy diet is low in sodium (salt), added sugars, solid ...

  12. Common Tests for Arrhythmia

    Science.gov (United States)

    ... much like sonar is used to study solid objects in the sea. You may only think of ultrasound being used to monitor a baby's ... much like sound waves used to study solid objects in the sea (sonar). You may only think of ultrasound being used to monitor a baby's ...

  13. Types of Arrhythmia

    Science.gov (United States)

    ... the atria (the heart's upper chambers) are called premature atrial contractions, or PACs. Premature beats that occur in the ventricles (the heart's ... happen naturally. However, some heart diseases can cause premature beats. They also ... and irregular contraction of the atria. In AF, the heart's electrical ...

  14. A novel mutation in the RYR2 gene leading to catecholaminergic polymorphic ventricular tachycardia and paroxysmal atrial fibrillation: dose-dependent arrhythmia-event suppression by β-blocker therapy.

    Science.gov (United States)

    Kazemian, Pedram; Gollob, Michael H; Pantano, Alfredo; Oudit, Gavin Y

    2011-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a genetic condition that presents with exercise-induced polymorphic arrhythmias. We describe a case report of a 25-year-old woman who had a cardiac arrest due to ventricular fibrillation. Genetic analysis revealed a novel missense mutation in exon 90 of the ryanodine receptor (RyR2) gene resulting in substitution of arginine for serine at residue 4153 (S4153R). The patient received an implantable cardioverter-defibrillator and low-dose β-blocker therapy. She had recurrent polymorphic ventricular arrhythmias treated with appropriate cardioverter-defibrillator shocks and paroxysmal atrial fibrillation. Titration of β-blocker to a much higher dose suppressed further episodes of ventricular arrhythmia and paroxysmal atrial fibrillation, resulting in reduction in device therapies.

  15. Induction of chagasic-like arrhythmias in the isolated beating hearts of healthy rats perfused with Trypanosoma cruzi-conditioned medium

    Directory of Open Access Journals (Sweden)

    H. Rodriguez-Angulo

    2013-01-01

    Full Text Available Chagas' myocardiopathy, caused by the intracellular protozoan Trypanosoma cruzi, is characterized by microvascular alterations, heart failure and arrhythmias. Ischemia and arrythmogenesis have been attributed to proteins shed by the parasite, although this has not been fully demonstrated. The aim of the present investigation was to study the effect of substances shed by T. cruzi on ischemia/reperfusion-induced arrhythmias. We performed a triple ischemia-reperfusion (I/R protocol whereby the isolated beating rat hearts were perfused with either Vero-control or Vero T. cruzi-infected conditioned medium during the different stages of ischemia and subsequently reperfused with Tyrode's solution. ECG and heart rate were recorded during the entire experiment. We observed that triple I/R-induced bradycardia was associated with the generation of auricular-ventricular blockade during ischemia and non-sustained nodal and ventricular tachycardia during reperfusion. Interestingly, perfusion with Vero-infected medium produced a delay in the reperfusion-induced recovery of heart rate, increased the frequency of tachycardic events and induced ventricular fibrillation. These results suggest that the presence of parasite-shed substances in conditioned media enhances the arrhythmogenic effects that occur during the I/R protocol.

  16. Implications of the Turing completeness of reaction-diffusion models, informed by GPGPU simulations on an XBox 360: cardiac arrhythmias, re-entry and the Halting problem.

    Science.gov (United States)

    Scarle, Simon

    2009-08-01

    In the arsenal of tools that a computational modeller can bring to bare on the study of cardiac arrhythmias, the most widely used and arguably the most successful is that of an excitable medium, a special case of a reaction-diffusion model. These are used to simulate the internal chemical reactions of a cardiac cell and the diffusion of their membrane voltages. Via a number of different methodologies it has previously been shown that reaction-diffusion systems are at multiple levels Turing complete. That is, they are capable of computation in the same manner as a universal Turing machine. However, all such computational systems are subject to a limitation known as the Halting problem. By constructing a universal logic gate using a cardiac cell model, we highlight how the Halting problem therefore could limit what it is possible to predict about cardiac tissue, arrhythmias and re-entry. All simulations for this work were carried out on the GPU of an XBox 360 development console, and we also highlight the great gains in computational power and efficiency produced by such general purpose processing on a GPU for cardiac simulations.

  17. Nicotinic Acid Adenine Dinucleotide Phosphate (NAADP)-mediated Calcium Signaling and Arrhythmias in the Heart Evoked by β-Adrenergic Stimulation*♦

    Science.gov (United States)

    Nebel, Merle; Schwoerer, Alexander P.; Warszta, Dominik; Siebrands, Cornelia C.; Limbrock, Ann-Christin; Swarbrick, Joanna M.; Fliegert, Ralf; Weber, Karin; Bruhn, Sören; Hohenegger, Martin; Geisler, Anne; Herich, Lena; Schlegel, Susan; Carrier, Lucie; Eschenhagen, Thomas; Potter, Barry V. L.; Ehmke, Heimo; Guse, Andreas H.

    2013-01-01

    Nicotinic acid adenine dinucleotide phosphate (NAADP) is the most potent Ca2+-releasing second messenger known to date. Here, we report a new role for NAADP in arrhythmogenic Ca2+ release in cardiac myocytes evoked by β-adrenergic stimulation. Infusion of NAADP into intact cardiac myocytes induced global Ca2+ signals sensitive to inhibitors of both acidic Ca2+ stores and ryanodine receptors and to NAADP antagonist BZ194. Furthermore, in electrically paced cardiac myocytes BZ194 blocked spontaneous diastolic Ca2+ transients caused by high concentrations of the β-adrenergic agonist isoproterenol. Ca2+ transients were recorded both as increases of the free cytosolic Ca2+ concentration and as decreases of the sarcoplasmic luminal Ca2+ concentration. Importantly, NAADP antagonist BZ194 largely ameliorated isoproterenol-induced arrhythmias in awake mice. We provide strong evidence that NAADP-mediated modulation of couplon activity plays a role for triggering spontaneous diastolic Ca2+ transients in isolated cardiac myocytes and arrhythmias in the intact animal. Thus, NAADP signaling appears an attractive novel target for antiarrhythmic therapy. PMID:23564460

  18. Huangzhi Oral Liquid Prevents Arrhythmias by Upregulating Caspase-3 and Apoptosis Network Proteins in Myocardial Ischemia-Reperfusion Injury in Rats

    Directory of Open Access Journals (Sweden)

    Xu Ran

    2015-01-01

    Full Text Available To study the effect of Huangzhi oral liquid (HZOL on I/R after 2 h and 4 h and determine its regulatory function on caspase-3 and protein networks. 70 SD male rats were randomly divided into seven groups and established myocardial I/R injury model by ligating the left anterior descending coronary artery. Myocardial infarction model was defined by TTC staining and color of the heart. The levels of CK-MB, CTnI, C-RPL, SOD, and MDA were tested at 2 h and 4 h after reperfusion. HE staining and ultramicrostructural were used to observe the pathological changes. The apoptotic index (AI of cardiomyocyte was marked by TUNEL. The expression levels of caspase-3, p53, fas, Bcl-2, and Bax were tested by immunohistochemistry and western blot. HZOL corrected arrhythmia, improved the pathologic abnormalities, decreased CK-MB, CTnI, C-RPL, MDA, AI, caspase-3, p53, fas, and Bax, and increased SOD ans Bcl-2 with different times of myocardial reperfusion; this result was similar to the ISMOC (P>0.05. HZOL could inhibit arrhythmia at 2 and 4 h after I/R and ameliorate cardiac function, which was more significant at 4 h after reperfusion. This result may be related to decreased expression of caspase-3, p53, and fas and increased Bcl-2/Bax ratio.

  19. Role of Pre-incision, Intravenous Prophylactic Amiodarone to Control Arrhythmias in Patients with Rheumatic Valvular Heart Disease undergoing Mitral Valve Replacement

    International Nuclear Information System (INIS)

    Objective: To evaluate the effect of intra-operative single intra venous dose of amiodarone on post operative cardiac arrhythmias in patients undergoing valvular heart surgery. Study Design: Randomized controlled trials. Place and Duration of surgery: This study was performed at Armed forces Institute of Cardiology Rawalpindi from Jan 01, 2011 to Dec 31, 2011. Patients and Methods: In this study 80 patients with rheumatic valvular heart disease and undergoing elective mitral valve replacement were randomly divided into two groups. Group I, n = 40 (Amiodarone group) was given single intravenous dose of amiodarone (5 mg/kg in 100 ml of saline over 30 min) before sternotomy incision. Group II, n = 40(control / placebo group) was given 100 ml of saline over 30 min. Result: In the amiodarone group, after removal of aortic cross clamp 75% patients had sinus rhythm compared to 47.5% in control group. p=0.045. Similarly 15% had AF, 5% JR and 5% VT/VF in amiodarone group in contrast to 32.5% with AF, 12.5% JR and 7.5% Vt/VF in control group. (p=0.045). Response to cardioversion was positive in 75% of the patients requiring shocks in amiodarone group as against 43.75% in the control group. (p=0.044). Conclusion: A single intravenous bolus dose of amiodarone is effective in decreasing the incidence of cardiac arrhythmias after mitral valve replacement in patients with rheumatic MVD. (author)

  20. Efficacy of dofetilide in the treatment of atrial fibrillation-flutter in patients with reduced left ventricular function: a Danish investigations of arrhythmia and mortality on dofetilide (diamond) substudy

    DEFF Research Database (Denmark)

    Pedersen, O D; Bagger, H; Keller, N;

    2001-01-01

    BACKGROUND: In patients with left ventricular dysfunction, atrial fibrillation and flutter (AF and AFl, respectively) are common arrhythmias associated with increased morbidity and mortality. The present study investigated the potential of dofetilide in AF-AFl patients with left ventricular...... dysfunction to restore and maintain sinus rhythm, which might reduce mortality and hospitalizations. METHODS AND RESULTS: In the Danish Investigations of Arrhythmia and Mortality ON Dofetilide (DIAMOND) studies, 506 patients were in AF-AFl at baseline. Over the course of study, cardioversion occurred in 148...

  1. Wavelet Analysis for Electrocardiogram Variation of Arrhythmia Patients%心律不齐患者心电图变异的小波分析

    Institute of Scientific and Technical Information of China (English)

    阮月平; 张佃中; 张屹

    2012-01-01

    To explore the energy proportion of the QRS complexes in the electrocardiogram (ECG),a new method,wavelet analysis,has been presented. Using wavelet transform of ECG,we can calculate the energy proportion of QRS complexes in multiple scales. The electrocardiograms (ECGs) were used as the experimental data,which were collected from a young (21-34yr) group and an elderly (68-81yr) group of healthy subjects,as well as from a group of arrhythmia patients (66-81yr). the data analysis was performed with the energy proportion of the QRS complexes in the ECG using Mexican-Hat as a mother wavelet in multiple scales. Results showed that the energy proportion of the QRS complexes had no changes with ages increasing (P>0. 44),but in the same age group,the arrhythmia pa-tients' energy proportion of the QRS complexes near 17Hz are obviously less than that in the healthy group (P< 0. 01),so the energy proportion of the QRS complexes calculated by wavelet analysis can be used as a feature index to judge whether a person is a sinus arrhythmia patient or not.%为探究心电图(ECG)中QRS波群能量占比,提出了对ECG进行小波变换,计算多尺度下QRS波群能量占比的新方法.以年轻(21~34岁)与年老(68~81岁)两组健康人及一组心律不齐患者(68~81岁)30个个体的ECG为实验数据,用Mexican-Hat为母小波在多个小波变换尺度下对ECG中的QRS波群进行能量占比的计算.结果表明,QRS波群的能量占比随年龄的增加无变化(P>0.44),但在相同年龄组,QRS波群能量占比在17 Hz附近心律不齐患者组明显小于健康组(P<0.01),从而确定利用小波分析法计算出的QRS波能量占比可以作为检测窦性心律不齐患者的一项特征指标.

  2. Aconitine-induced Ca{sup 2+} overload causes arrhythmia and triggers apoptosis through p38 MAPK signaling pathway in rats

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Gui-bo; Sun, Hong; Meng, Xiang-bao [Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193 (China); Hu, Jin; Zhang, Qiang; Liu, Bo [Academy of Chinese Medical Sciences of Jilin Province, Changchun, Jilin 130021 (China); Wang, Min [Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193 (China); Xu, Hui-bo, E-mail: xhb_6505@163.com [Academy of Chinese Medical Sciences of Jilin Province, Changchun, Jilin 130021 (China); Sun, Xiao-bo, E-mail: sun_xiaobo163@163.com [Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193 (China)

    2014-08-15

    Aconitine is a major bioactive diterpenoid alkaloid with high content derived from herbal aconitum plants. Emerging evidence indicates that voltage-dependent Na{sup +} channels have pivotal roles in the cardiotoxicity of aconitine. However, no reports are available on the role of Ca{sup 2+} in aconitine poisoning. In this study, we explored the importance of pathological Ca{sup 2+} signaling in aconitine poisoning in vitro and in vivo. We found that Ca{sup 2+} overload lead to accelerated beating rhythm in adult rat ventricular myocytes and caused arrhythmia in conscious freely moving rats. To investigate effects of aconitine on myocardial injury, we performed cytotoxicity assay in neonatal rat ventricular myocytes (NRVMs), as well as measured lactate dehydrogenase level in the culture medium of NRVMs and activities of serum cardiac enzymes in rats. The results showed that aconitine resulted in myocardial injury and reduced NRVMs viability dose-dependently. To confirm the pro-apoptotic effects, we performed flow cytometric detection, cardiac histology, transmission electron microscopy and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. The results showed that aconitine stimulated apoptosis time-dependently. The expression analysis of Ca{sup 2+} handling proteins demonstrated that aconitine promoted Ca{sup 2+} overload through the expression regulation of Ca{sup 2+} handling proteins. The expression analysis of apoptosis-related proteins revealed that pro-apoptotic protein expression was upregulated, and anti-apoptotic protein BCL-2 expression was downregulated. Furthermore, increased phosphorylation of MAPK family members, especially the P-P38/P38 ratio was found in cardiac tissues. Hence, our results suggest that aconitine significantly aggravates Ca{sup 2+} overload and causes arrhythmia and finally promotes apoptotic development via phosphorylation of P38 mitogen-activated protein kinase. - Highlights: • Aconitine-induced Ca

  3. Clinical Study on Amiodarone in the Treatment of Cardiac Arrhythmia%胺碘酮治疗心律失常的临床研究

    Institute of Scientific and Technical Information of China (English)

    赵明琴

    2016-01-01

    Objective Amiodarone treatment method and its effect for patients with cardiac arrhythmia are to be investigated.MethodsChose 66 patients with cardiac arrhythmia who were treated in hospital from August 2014 to September 2015 and separated them into two groups at random, 37 patients in study group were given Amiodarone treatment, while another 29 patients in control group were given Lidocaine treatment, and then compared treatment effects between two groups.Results Patients’treatment efficacy was 91.89% in study group, which was much higher than 82.76% in control group, thus, treatment efficacy in study group was much better and such a differential had statistic value(P<0.05).Conclusion For patients with cardiac arrhythmia, Amiodarone treatment is quite effective and safe to improve their physical symptom with few side effect.%目的:探究心律失常患者采取胺碘酮治疗的方法和效果。方法选取2014年8月~2015年9月收治的66例心律失常患者进行治疗研究,随机分组,实验组37例患者采取胺碘酮治疗,对照组29例患者选择利多卡因治疗,比较两组患者的治疗效果。结果实验组治疗总有效率为91.89%,对照组治疗总有效率为82.76%,实验组治疗总有效率高于对照组,差异有统计学意义(P<0.05)。结论心律失常患者采取胺碘酮治疗,可改善身体症状,效果显著,不良反应较少,安全性高。

  4. 胺碘酮治疗室性心律失常的临床疗效观察%Effect of amiodarone in the treatment of ventricular arrhythmia

    Institute of Scientific and Technical Information of China (English)

    张育辉

    2015-01-01

    目的:探讨胺碘酮治疗室性心律失常的临床效果。方法:选择观察组40例室性心律失常患者,随机分为观察组和对照组。观察组给予胺碘酮治疗,对照组给予利多卡因治疗,观察两组疗效。结果:观察组显效15例(占75%),有效4例(占20.0%),无效1例(占5.0%);对照组临床效果评定结果:显效9例(占45.0%),有效5例(占25.0%),无效6例(占30.0%);观察组总有效率(95.0%)高于对照组总有效率(70.0%),差异有统计学意义( P<0.05)。结论:胺碘酮治疗室性心律失常疗效显著,值得借鉴。%Objective To explore the clinical effect of amiodarone in treatment of ventricular arrhythmia. Method 40 cases with ven-tricular arrhythmia were selected and randomly divided into observation group and control group. The observation group was treated with amiodarone,the control group was given lidocaine. the curative effect of two groups was observed. Results The effect in observation group:26 cases were significant effect(75%),5 cases were effective(20%),1 cases was invalid(5. 0 %);the effect in control group:9 cases were significant effect(45. 0%),5 cases were effective(25. 0%),6 cases were invalid(30. 0%);the total effective rate in the observa-tion group(95. 0%)was higher than that in the control group(70. 0%),the difference was statistically significant(P<0. 05). Conclu-sion Amiodarone in the treatment of ventricular arrhythmia has significant effect,and which is worth learning.

  5. Excellent survival and low incidence of arrhythmias, stroke and heart failure long-term after surgical ASD closure at young age. A prospective follow-up study of 21-33 years

    NARCIS (Netherlands)

    J.W. Roos-Hesselink (Jolien); F.J. Meijboom (Folkert); S.E.C. Spitaels (Silja); E.M.W.J. Utens (Elisabeth); A.J.J.C. Bogers (Ad); M.L. Simoons (Maarten); E.H.M. van Rijen (Susan); R.T. van Domburg (Ron)

    2003-01-01

    textabstractAIMS: Although studies have suggested good long-term results, arrhythmias, pulmonary hypertension and left ventricular dysfunction are mentioned as sequelae long-term after surgical atrial septal defect closure at young age. Most studies were performed only by questionnaire and in a retr

  6. The occurrence of new arrhythmias after catheter-ablation of accessory pathway: Delayed arrhythmic side-effect of curative radiofrequency lesion?

    Directory of Open Access Journals (Sweden)

    Mujović Nebojša

    2011-01-01

    Full Text Available Introduction. New arrhythmias (NA may appear late after accessory pathway (AP ablation, but their relation to curative radiofrequency (RF lesion is unknown. Objective. The aim of this study was to determine the prevalence and predictors for NA occurrence after AP ablation and to investigate pro-arrhythmic effect of RF. Methods. Total of 124 patients (88 males, mean age 43±14 years with Wolff-Parkinson-White syndrome and single AP have been followed after successful RF ablation. Post-ablation finding of arrhythmia, not recorded before the procedure, was considered a NA. The origin of NA was assessed by analysis of P-wave and/or QRS-complex morphology, and, thereafter, it was compared with locations of previously ablated APs. Results. Over the follow-up of 4.3±3.9 years, NA was registered in 20 patients (16%. The prevalence of specific NAs was as follows: atrioventricular (AV block 0.8%, atrial premature beats 1.6%, atrial fibrillation 5.4%, atrial flutter 0.8%, sinus tachycardia 4.8%, ventricular premature beats (VPBs 7.3%. Multivariate Cox-regression analysis identified (1 pre-ablation history of pathway-mediated tachyarrhythmias >10 years (HR=3.54, p=0.016 and (2 septal AP location (HR=4.25, p=0.003, as the independent predictors for NA occurrence. In four NA cases (two cases of septal VPBs, one of typical AFL and one of AV-block presumed NA origin was identified in the vicinity of previous ablation target. Conclusion. NAs were found in 16% of patients after AP elimination. In few of these cases, late on-site arrhythmic effect of initially curative RF lesion might be possible. While earlier intervention could prevent NA occurrence, closer follow-up is advised after ablation of septal AP.

  7. Evidence for a respiratory component, similar to mammalian respiratory sinus arrhythmia, in the heart rate variability signal from the rattlesnake, Crotalus durissus terrificus.

    Science.gov (United States)

    Campbell, Hamish A; Leite, Cleo A C; Wang, Tobias; Skals, Marianne; Abe, Augusto S; Egginton, Stuart; Rantin, F Tadeu; Bishop, Charles M; Taylor, Edwin W

    2006-07-01

    Autonomic control of heart rate variability and the central location of vagal preganglionic neurones (VPN) were examined in the rattlesnake (Crotalus durissus terrificus), in order to determine whether respiratory sinus arrhythmia (RSA) occurred in a similar manner to that described for mammals. Resting ECG signals were recorded in undisturbed snakes using miniature datalogging devices, and the presence of oscillations in heart rate (fh) was assessed by power spectral analysis (PSA). This mathematical technique provides a graphical output that enables the estimation of cardiac autonomic control by measuring periodic changes in the heart beat interval. At fh above 19 min(-1) spectra were mainly characterised by low frequency components, reflecting mainly adrenergic tonus on the heart. By contrast, at fh below 19 min(-1) spectra typically contained high frequency components, demonstrated to be cholinergic in origin. Snakes with a fh >19 min(-1) may therefore have insufficient cholinergic tonus and/or too high an adrenergic tonus acting upon the heart for respiratory sinus arrhythmia (RSA) to develop. A parallel study monitored fh simultaneously with the intraperitoneal pressures associated with lung inflation. Snakes with a fhrate (fv). Adrenergic blockade by propranolol infusion increased the variability of the ventilation cycle, and the oscillatory component of the fh spectrum broadened accordingly. Infusion of atropine to effect cholinergic blockade abolished this HF component, confirming a role for vagal control of the heart in matching fh and fv in the rattlesnake. A neuroanatomical study of the brainstem revealed two locations for vagal preganglionic neurones (VPN). This is consistent with the suggestion that generation of ventilatory components in the heart rate variability (HRV) signal are dependent on spatially distinct loci for cardiac VPN. Therefore, this study has demonstrated the presence of RSA in the HRV signal and a dual location for VPN in the

  8. 儿童短QT间期综合征与恶性心律失常的预后研究%Effects of Short QT Syndrome and Malignant Arrhythmia on Prognosis in Children

    Institute of Scientific and Technical Information of China (English)

    黄佐贵; 杜国伟; 殷波; 李倩; 金海燕

    2011-01-01

    目的 探讨儿童短QT间期综合征(SQTS)与恶性心律失常的预后意义.方法 随机测量18例儿童常规12导联心电图(ECG)QT Fridercia(QTfc)和QT Nomogram(QTnc)间期,根据R-R间期(R-R)和心率(HR)计算QT间期校正值(QT Fridercia、QT Nomogram).QT Fridercia、QT Nomogram 间期≤300 ms为短QT间期,观察短QT Fridercia、QT Nomo-gram间期与恶性心律失常的关系.用奎尼丁、氟卡尼和除颤器(Implanted cardioverter-defibrillator)治疗观察其预后.结果 QT Fridercia≤300 ms发生心律失常为100%,QT Nomogram≤300 ms发生心律失常为100%;奎尼丁、氟卡尼可使QT间期值平均延长20 ms,减少恶性心律失常发生,P<0.05.单用奎尼丁、氟卡尼治疗2年内心律失常发生率QT Fridercia44.44%,QT Nomogram 44.44%;死亡率分别为11.11%、11.11%.除颤器治疗6例SQTS患者在2年的观察中无恶性心律失常发生和死亡率发生,P<0.05.结论 短QT间期与恶性心律失常有关;奎尼丁、氟卡尼能延长QT间期,可减少恶性心律失常发生;ICD能有效防止恶性心律失常的发生率和死亡率.%Objective To explore the effects of short QT syndrome and malignant arrhythmia on the prognosis in children.Methods The QT Fridercia(QTfc) and QT Nomogram(QTnc) were calculated by determining the conventional twelve lead ECG of eighteen children. The relation between the short QT interval( QT Fridercia and QT Nomogram interval≤300 ms) and the malignant arrhythmia was evaluated. Quinidine, Flecainide and implanted cardioverter-debrillator (ICD) were used to treat the arrhythmia,and the prognosis was observed. Results The rate of arrhythmia were both 100% in cases with QT Fridercia≤300 ms and QT Nomogram ≤300 ms. Quinidine and Flecainide prolonged QT interval average by 20 ms,and decreased the rate of malignant arrhythmia( P < 0.05 ). The rate of malignant arrhythmia and mortality in patients treated only with Quinidine orecainide in two years was 44. 44% and 11. 11

  9. 大鼠超负荷运动下的心律紊乱规律分析%Analysis of Arrhythmia Rule Under Rat Overload Exercise Condition

    Institute of Scientific and Technical Information of China (English)

    刘昊

    2014-01-01

    目的:分析大鼠超负荷运动下心律紊乱规律。方法:按照不同摄氧量,将80只实验大鼠随机分为4组,并对大鼠的最大耗氧量、1min心率、呼吸频率以及心脏结蛋白的基因表达等指标进行检测。结果:在超负荷跑台运动中,受试大鼠心律在现低、中、高负荷时偏低,而最大负荷时偏高,中、高负荷及最大负荷运动时心率值同对照组存在显著差异(P<0.05)。在恒定负荷运动中,大鼠的心律值整体偏低。运动组大鼠心律、呼吸频率、呼吸商以及摄氧量等指标相关系数远远低于对照组。不同强度负荷运动后,大鼠窦房结结蛋白mRNA表达量基本一致,但60%摄氧量运动下大鼠窦房结结蛋白mRNA表达量明显下降(P<0.05)。超负荷运动后,大鼠房室结结蛋白mRNA表达量基本一致,但60%最大摄氧量超负荷运动下大鼠后房室结结蛋白mRNA表达量出现显著下降趋势(P<0.05)。结论:大鼠超负荷运动可导致心脏结蛋白受损,心律紊乱程度加强。%Objective: to analyze the arrhythmia rule under rat overload exercise condition. Methods: 80 experimental rats were randomly divided into four groups. Then, the indicators such as maximum oxygen consumption, 1 min heart rate, and respiratory frequency as well as mRNA expression of rat’s heart knot protein using real-time fluorescent quantitative PCR were detected and analyzed. Results:in the overload running machine exercise, the heart rates of the rat were lower in the low-loading, medium-loading and high-loading groups, while in the maximum load exercise, the heart rates of the rat were higher and compared with control group, the heart rate value in high-loading, medium-loading and maximum-loading group were significant differences (P<0.05). In constant loading, the heart rate value of rat was overall lower. The correlation coefficients of cardiac arrhythmia, respiratory frequency, respiratory

  10. Sympathetic overactivity and arrhythmias in tetanus: electrocardiographic analysis Hiperatividade simpática e arritmias no tétano: análise eletrocardiográfica

    Directory of Open Access Journals (Sweden)

    Gustavo Trindade Henriques Filho

    2007-02-01

    Full Text Available As a result of the advances in the control of pulmonary insufficiency in tetanus, the cardiovascular system has increasingly been shown to be a determining factor in morbidity and mortality but detailed knowledge of the cardiovascular complications in tetanus is scanty. The 24h-Holter was carried out in order to detect arrhythmias and sympathetic overactivity in 38 tetanus patients admitted to an ICU. The SDNN Index (standard deviation from the normal R-to-R intervals, was useful in detecting adrenergic tonus, and ranged from 64.1 ± 27 in the more severe forms of tetanus to 125 ± 69 in the milder ones. Sympathetic overactivity occurred in 86.2% of the more severe forms of the disease, but was also detected in 33% of the milder forms. Half the patients had their sympathetic overactivity detected only by the Holter. The most frequent arrhythmias were isolated supraventricular (55.2% and ventricular (39.4% extrasystoles. There was no association of the arrhythmias with the clinical form of tetanus or with the presence of sympathetic overactivity. The present study demonstrated that major cardiovascular dysfunction, particularly sympathetic overactivity, occurs in all forms of tetanus, even in the milder ones. This has not been effectively detected with traditional monitoring in ICU and may not be properly treated.Com os avanços no controle da insuficiência respiratória no tétano, o sistema cardiovascular tem participado de forma crescente na morbidade e mortalidade da doença, mas o conhecimento dessas complicações é escasso. No intuito de detectar arritmias e hiperatividade simpática, o holter de 24 h foi utilizado em 38 pacientes com tétano admitidos numa UTI de doenças infecciosas. O índice SDNN (desvio standard dos intervalos normais R-a-R, foi útil na detecção do tônus adrenérgico, e variou de 64,1 ± 27 nas formas mais severas de tétano a 125 ± 69 nas formas mais leves. Hiperatividade simpática ocorreu em 86,2% das formas

  11. Rate of cardiac arrhythmias and silent brain lesions in experienced marathon runners: rationale, design and baseline data of the Berlin Beat of Running study

    Directory of Open Access Journals (Sweden)

    Haeusler Karl

    2012-08-01

    Full Text Available Abstract Background Regular exercise is beneficial for cardiovascular health but a recent meta-analysis indicated a relationship between extensive endurance sport and a higher risk of atrial fibrillation, an independent risk factor for stroke. However, data on the frequency of cardiac arrhythmias or (clinically silent brain lesions during and after marathon running are missing. Methods/ Design In the prospective observational “Berlin Beat of Running” study experienced endurance athletes underwent clinical examination (CE, 3 Tesla brain magnetic resonance imaging (MRI, carotid ultrasound imaging (CUI and serial blood sampling (BS within 2-3 days prior (CE, MRI, CUI, BS, directly after (CE, BS and within 2 days after (CE, MRI, BS the 38th BMW BERLIN-MARATHON 2011. All participants wore a portable electrocardiogram (ECG-recorder throughout the 4 to 5 days baseline study period. Participants with pathological MRI findings after the marathon, troponin elevations or detected cardiac arrhythmias will be asked to undergo cardiac MRI to rule out structural abnormalities. A follow-up is scheduled after one year. Results Here we report the baseline data of the enrolled 110 athletes aged 36-61 years. Their mean age was 48.8 ± 6.0 years, 24.5% were female, 8.2% had hypertension and 2.7% had hyperlipidaemia. Participants have attended a mean of 7.5 ± 6.6 marathon races within the last 5 years and a mean of 16 ± 36 marathon races in total. Their weekly running distance prior to the 38th BMW BERLIN-MARATHON was 65 ± 17 km. Finally, 108 (98.2% Berlin Beat-Study participants successfully completed the 38th BMW BERLIN-MARATHON 2011. Discussion Findings from the “Berlin Beats of Running” study will help to balance the benefits and risks of extensive endurance sport. ECG-recording during the marathon might contribute to identify athletes at risk for cardiovascular events. MRI results will give new insights into the link

  12. Arrhythmia caused by Sjogren's syndrome complicated with primary biliary cirrhosis%干燥综合征并原发性胆汁性肝硬化致多种心律失常

    Institute of Scientific and Technical Information of China (English)

    沈敏; 曾学军

    2011-01-01

    To present a case of multiple arrhythmia caused by Sjogren's syndrome complicated with primary biliary cirrhosis. To improve the knowledgement of physicians to such kind of patients.%报道1例出现多种心律失常的干燥综合征并原发性胆汁性肝硬化患者,以提高对此类患者的诊治水平.

  13. 慢性肺源性心脏病并发心律失常68例临床诊断与治疗%Clinical Diagnosis and Treatment of 68 Cases of Chronic Pulmonary Heart Disease Complicated With Arrhythmia

    Institute of Scientific and Technical Information of China (English)

    许文华; 李志军

    2015-01-01

    Objective To investigate the clinical diagnosis and treatment of chronic pulmonary heart disease with arrhythmia. Methods The clinical data of 68 patients with chronic pulmonary heart disease with arrhythmia were retrospectively analyzed. Results Manifestation of cardiac arrhythmias with sinus bradycardia slow, sinus tachycardia, speed, atrial flutter, atrial fibrillation, paroxysmal supraventricular tachycardia tachycardia, paroxysmal atrial tachycardia, speed and other kinds of. Conclusion The clinical analysis of chronic pulmonary heart disease with arrhythmia patients, need to be based on the ECG in order to understand the use of how to diagnose and treatment.%目的:探讨慢性肺源性心脏病并发心律失常的临床诊断和治疗。方法对我院收治的68例慢性肺源性心脏病并发心律失常患者的临床资料进行回顾性分析。结果心律失常的表现类型有窦性心动过缓、窦性心动过速、心房扑动、心房颤动、阵发性室性心动过速、阵发性房性心动过速等多种。结论临床分析慢性肺源性心脏病并发心律失常患者时,需要依据心电图以便深入了解诊断和治疗的方法。

  14. Observation and Nursing Intervention of Amiodarone in the Treatment of Arrhythmia%胺碘酮治疗心率失常的疗效观察和护理干预分析

    Institute of Scientific and Technical Information of China (English)

    王晓荣

    2015-01-01

    目的:探讨使用胺碘酮治疗心率失常的临床效果及护理干预措施。方法回顾性分析入住我院治疗心率失常的62例患者,随机分为两组做比对性分析。结果观察组患者的治疗效果较好,总有效率高于对照组,差异有统计学意义(P<0.05)。结论使用胺腆酮治疗心率失常的临床疗效确切,加以综合护理干预可有效提高胺腆酮的治疗效果,减少并发症的发生。%Objective To investigate the clinical effect and nursing intervention measures of the use of amiodarone in the treatment of arrhythmia. Methods 62 cases of patients with arrhythmia were analyzed in our hospital, were randomly divided into two groups to do a comparison analysis. Results The effect of the observation group was significantly higher than that of the control group, the difference was statistically significant (P<0.05). Conclusion Use of amiodarone in the treatment of arrhythmia clinical curative effect, the comprehensive nursing intervention can effectively improve the therapeutic effect of amiodarone, reduce complications.

  15. The Clinical Research of Amiodarone in the Treatment of Patients With Heart Failure Combined With Arrhythmia%胺碘酮治疗心衰合并心律失常患者的临床研究

    Institute of Scientific and Technical Information of China (English)

    许波

    2015-01-01

    目的:分析胺碘酮治疗心衰合并心律失常的效果。方法选取心衰合并心律失常患者42例,均给予胺碘酮治疗。结果42例患者总有效率95.2%,用药后心功能较用药前明显改善,无严重不良反应,仅2例胃肠道不适,经对症处理后好转。结论胺碘酮治疗心衰合并心律失常效果显著。%Objective To analysis the effect of amiodarone in the treatment of heart failure combined with arrhythmia. Methods 42 cases of patients with heart failure combined with arrhythmia were selected and all patients were given amiodarone treatment. Results After treatment,the total effective rate was 95.2%in 42 cases. The cardiac function of patients were significantly improved than before treatment. There was no serious adverse reaction. Only 2 patients had gastrointestinal discomfort and they were cured after symptomatic treatment. Conclusion The effect of amiodarone in treatment of heart failure combined with arrhythmia is significantly.

  16. 胺碘酮治疗心衰伴心律失常的临床分析%Therapeutic effects of amiodarone on chronic heart failure complicated by arrhythmia

    Institute of Scientific and Technical Information of China (English)

    周兰珠

    2010-01-01

    目的 评价胺碘酮治疗心力衰竭(HF)伴心律失常的疗效.方法 选择心力衰竭合并心律失常患者96例,在抗心衰治疗同时给予口服胺碘酮6周.结果 治疗6周后观察总有效率91.9%.结论 胺碘酮治疗HF伴心律失常安全、有效.%Objective To evaluate the the therapeutic effects of amiodarone on chronic heart failure complicated by arrhythmia. Methods From 2006 to 2008,96 chronic congestive heart failure patients with arrhythmia were enrolled. All patients were given standard medical treatment according to the current practice guidelines with a β-blocker, an angiotensin-converting enzyme(ACE) inhibitor, and diuretics. At the same time,they were also given oral amiodarone for six weeks. Results After 6 weeks' treatment with amiodarone,the total effective therapeutic effects was 91.9 percent. Conclusion For patients with chronic congestive heart failure complicated by with arrhythmia, amiodarone treatment for six weeks is safe and effective.

  17. Effect of amiodarone therapy on mortality in patients with left ventricular dysfunction and asymptomatic complex ventricular arrhythmias: Argentine Pilot Study of Sudden Death and Amiodarone (EPAMSA).

    Science.gov (United States)

    Garguichevich, J J; Ramos, J L; Gambarte, A; Gentile, A; Hauad, S; Scapin, O; Sirena, J; Tibaldi, M; Toplikar, J

    1995-09-01

    The efficiency of prophylactic antiarrhythmic treatment with amiodarone in reducing 1-year mortality in patients with reduced left ventricular ejection fraction ( < 35%) and asymptomatic ventricular arrhythmias (Lown classes 2 and 4) was investigated in a prospective, multicenter, randomized, controlled study. Among 127 patients who entered the study, 61 were assigned to no antiarrhythmic therapy (control group [CG] and 66 to amiodarone treatment (amiodarone group [AG]). Amiodarone was administered at a dosage of 800 mg/day for 2 weeks followed by 400 mg/day thereafter. A 12-month follow-up was completed for 106 patients (57 in the AG and 49 in the CG). Amiodarone reduced the overall mortality rate, which was 10.5% in the AG versus 28.6% in the CG (odds ratio [OR] 0.29; 95% confidence interval [CI] 0.10 to 0.84; log-rank test 0.02) and sudden death rate, which was 7.0% in the AG versus 20.4% in the CG (OR 0.29; 95% CI 0.08 to 1.00; log-rank test 0.04). Side effects were rare, and in only three patients did amiodarone treatment have to be discontinued.

  18. Global and regional left ventricular strain indices in post-myocardial infarction patients with ventricular arrhythmias and moderately abnormal ejection fraction.

    Science.gov (United States)

    Nguyen, Bich Lien; Capotosto, Lidia; Persi, Alessandro; Placanica, Attilio; Rafique, Asim; Piccirillo, Gianfranco; Gaudio, Carlo; Gang, Eli S; Siegel, Robert J; Vitarelli, Antonio

    2015-02-01

    The aim of the study described here was to compare myocardial strains in ischemic heart patients with and without sustained ventricular tachycardia (VT) and moderately abnormal left ventricular ejection fraction (LVEF) to investigate which index could better predict VT on the basis of the analysis of global and regional left ventricular (LV) dysfunction. We studied 467 patients with previous myocardial infarction and LVEF >35%. Fifty-one patients had documented VT, and 416 patients presented with no VT. LV volumes and score index were obtained by 2-D echocardiography. Longitudinal, radial and circumferential strains were determined. Strains of the infarct, border and remote zones were also obtained. There were no differences in standard LV 2-D parameters between patients with and those without VT. Receiver operating characteristic values were -12.7% for global longitudinal strain (area under the curve [AUC] = 0.72), -4.8% for posterior-inferior wall circumferential strain (AUC = 0.80), 61 ms for LV mechanical dispersion (AUC = 0.84), -10.1% for longitudinal strain of the border zone (AUC = 0.86) and -9.2% for circumferential strain of the border zone (AUC = 0.89). In patients with previous myocardial infarction and moderately abnormal LVEF, peri-infarct circumferential strain was the strongest predictor of documented ventricular arrhythmias among all strain quantitative indices. Additionally, strain values from posterior-inferior wall infarctions had a higher association with arrhythmic events compared with global strain.

  19. Respiratory sinus arrhythmia feedback in a stressed population exposed to a brief stressor demonstrated by quantitative EEG and sLORETA.

    Science.gov (United States)

    Sherlin, Leslie; Muench, Fred; Wyckoff, Sarah

    2010-09-01

    Previous investigations of electroencephalograms during relaxation have identified increases in slow wave band power, correlations between increased levels of alpha activity with lower levels of anxiety, and autonomic changes characterized by otherwise documented decreased sympathetic activity. This study was carried out to determine the overall changes in quantitative electroencephalographic activity and the current source as a result of an acute session of respiratory sinus arrhythmia (RSA) biofeedback in a population of subjects experiencing stress. This study's findings provide physiological evidence of RSA feedback effect and suggest that RSA training may decrease arousal by promoting an increase of alpha band frequencies and decrease in beta frequencies overall and in areas critical to the regulation of stress. It was of interest that novices could achieve these objective alterations in EEG activity after minimal training and intervention periods considering that the previous literature on EEG and meditative states involve experienced meditators or participants who had been given extensive training. Additionally, these effects were present immediately following the training suggesting that the intervention may have effects beyond the actual practice. PMID:20414803

  20. 心律失常患者冠状动脉CTA成像%Coronary computed tomography angiography in patients with arrhythmia

    Institute of Scientific and Technical Information of China (English)

    何雯雯

    2012-01-01

    Coronary computed tomography angiography (CTA) has been widely applied in clinical practice , but arrhythmia has always been the bottleneck of the technology. Limited by the technological problems of multidetector spiral CT and dual-source CT, images always discontinue for the irregular cardiac rhythm. Electrocardiograph editing technology can improve image quality and diagnostic sensitivity. Wide-detector CT can rebuild the images by a single heartbeat in the case of low heart rate, which helps to eliminate artifacts, but its temporal resolution needs to be improved.%冠状动脉CT血管造影(CTA)目前已广泛应用于临床,但心律失常患者一直是此项技术的瓶颈.由于传统的螺旋CT及双源CT的技术限制,对心律失常患者扫描过程中往往因为心脏运动不规律,导致图像不连续.心电编辑技术可解决部分此类问题,改善图像的质量,提高诊断的灵敏度.宽探测器CT(如320排螺旋CT)在低心率条件下可在一个心动周期成像,能消除此类伪影,但时间分辨力尚待提高.