Cardioverter-defibrillator reduces mortality risk in eligible ischemic and non-ischemic cardiomyopathy patients: Sub-analysis of the multi-center Improve SCA study

Background & Objective: Despite the burden of sudden cardiac arrest (SCA) worldwide, implantable cardioverter-defibrillators (ICDs) are underutilized, particularly in Asia, Latin America, Eastern Europe, the Middle East, and Africa. The Improve SCA trial demonstrated that primary prevention (PP) patients in these regions benefit from an ICD or a cardiac resynchronization therapy defibrillator (CRT-D). We aimed to compare the rate of device therapy and mortality among ischemic and non-ischemic cardiomyopathy (ICM and NICM) PP patients who met guideline indications for ICD therapy and had an ICD/CRT-D implanted. Methods: Improve SCA was a prospective, non-randomized, non-blinded multicenter trial that enrolled patients from the above-mentioned regions. All-cause mortality and device therapy were examined by cardiomyopathy (ICM vs NICM) and implantation status. Cox proportional hazards methods were used, adjusting for factors affecting mortality risk. Results: Of 1848 PP NICM patients, 1007 (54.5%) received ICD/CRT-D, while 303 of 581 (52.1%) PP ICM patients received an ICD/CRT-D. The all-cause mortality rate at 3 years for NICM patients with and without an ICD/CRT-D was 13.1% and 18.3%, respectively (HR 0.51, 95% CI 0.38e0.68, p < 0.001). Similarly, all-cause mortality at 3 years in ICM patients was 13.8% in those with a device and 19.9% in those without an ICD/CRT-D (HR 0.54, 95% CI 0.33e.0.88, p ¼ 0.011). The time to first device therapy, time to first shock, and time to first antitachycardia pacing (ATP) therapy were not significantly different between groups (p 0.263). Conclusions: In this large data set of patients with a guideline-based PP ICD indication, defibrillator device implantation conferred a significant mortality benefit in both NICM and ICM patients. The rate of appropriate device therapy was also similar in both groups.

Cardiodesfibrilador implantable: estado del arte / Cardiac defibrillators: state of the art

Resumen La muerte súbita cardiaca es una consecuencia devastadora de las enfermedades estructurales del corazón y un problema de salud pública en todo el mundo; es responsable de alrededor del 50% de las muertes por causa cardiovascular. Su incidencia es mayor en personas por encima de los de 40 años, siendo en esta población la cardiopatía isquémica instaurada o durante la fase aguda del infarto al miocardio los factores de riesgo más importantes; sin embargo, hay otros factores no relacionados con isquemia, como la cardiomiopatía dilatada, hipertrófica o valvular. La fibrilación y la taquicardia ventricular son la causa más frecuente de muerte súbita cardiaca en adultos. Los cardiodesfibriladores implantables son ampliamente utilizados y recomendados por las sociedades de cardiología para la prevención primaria y secundaria de la muerte súbita cardiaca.

Abstract Sudden cardiac death is a devastating consequence of structural heart disease and a global public health problem, accounting for close to 50% of cardiovascular deaths. Its incidence is greater in people over the age of 40, with the most important risk factors being: established ischemic heart disease or ischemia during the acute phase of a myocardial infarction. However, there are other factors, unrelated to ischemia, such as dilated, hypertrophic, or valvular cardiomyopathy. Ventricular fibrillation and tachycardia are the most frequent causes of sudden cardiac death in adults. Implantable cardioverter-defibrillators are widely used and recommended by cardiology societies for primary and secondary prevention of sudden cardiac death.

Patient with an implantable cardiac electrical stimulation device. What should the anesthesiologist know? / Paciente con dispositivo de estimulación eléctrica cardiaca implantable. ¿Qué debe saber el anestesiólogo?

Abstract Patients with implantable electric stimulation devices are challenging to the anesthesiologist since these cases demand a comprehensive knowledge about how the device operates, the indications for the implant and the implications that must be addressed during the perioperative period. This article is intended to provide the reader with clear and structured information so that the anesthesiologist will be able to safely deal with the situation of a patient with an implantable cardiac stimulation device, who has been programmed for emergent surgery. A search for the scientific evidence available was conducted in Pubmed / Medline, ScienceDirect, OVID, SciELO), for a non-systematic review. The incidence of the use of cardiac electric stimulation devices has been growing. Their operation is increasingly complex, and demands being constantly updated on the knowledge in the area.

Resumen El paciente portador de un dispositivo de estimulación eléctrica cardiaca implantable se convierte en un reto para el anestesiólogo debido a que implica un conocimiento integral que abarca su funcionamiento, las indicaciones que llevaron a su implante y las implicaciones que se deben abordar en el perioperatorio. Este artículo busca proporcionar al lector información clara y estructurada que le permita al anestesiólogo enfrentarse de forma segura al escenario de un paciente con un dispositivo de estimulación eléctrica cardiaca implantable programado para cirugía emergente. Se realizó una búsqueda de la evidencia científica disponible en bases de datos (Pubmed / Medline, ScienceDirect, OVID, SciELO), para una revisión no sistemática. La incidencia en el uso de dispositivos de estimulación eléctrica cardiaca viene en aumento. Su funcionamiento es cada vez más complejo lo cual implica una actualización permanente del conocimiento en esta área.

Infecção de loja de cardioversor-desfibrilador implantável (CDI) por klebsiella sp. Carbapenem-resistente / Klebsiella sp. carbapenem-resistant pocket infection of an Implantable Cardioverter Defibrillator (ICD)

RESUMO: As infecções associadas aos Dispositivos Cardíacos Eletrônicos Implantáveis (DCEI) apresentam uma incidência de até 3,4% e notável impacto na morbidade e mortalidade dos pacientes. As bactérias Gram-positivas, especialmente do gênero Staphylococcus sp. representam 60-70% dos agentes isolados. Por sua vez, as Gram-negativas correspondem até 9% dos casos. Relatamos uma infecção de loja de gerador de Cardioversor-desfibrilador implantável (CDI) por uma Klebsiella sp. resistente aos carbapenêmicos, em um paciente masculino jovem, cujo desafiador diagnóstico de certeza desse caso somente foi possível após exploração cirúrgica e cultura do material da loja do CDI, haja vista a apresentação clínica oligossintomática. Embora já descritas, Klebsiella sp. são raras nesse contexto e em nosso conhecimento, esse é o primeiro relato de uma infecção de DCEI por uma enterobactéria resistente a carbapenêmico. (AU)

ABSTRACT: Infections associated with Implantable Electronic Cardiac Devices (IECD) have an incidence of up to 3.4% and a notable impact on patient morbidity and mortality. Gram-positive bacteria, especially Staphylococcus sp. represent 60-70% of isolated agents. In turn, gram-negatives account for up to 9% of cases. We report an Implantable Cardioverter-Defibrillator (ICD) generator pocket infection by a Carbapenem Resistant Klebsiella sp., in a young male patient, whose challenging diagnosis of certainty was only possible after surgical exploration and culture of the material from the ICD pocket, given the oligosymptomatic clinical presentation. Although already described, Klebsiella sp. are rare in this context and to our knowledge, this is the first report of an IECD infection by a carbapenem-resistant enterobacterium. (AU)

How Should ICDs Be Stopped in the Terminal Phase of Cancer?: Five Cases of Patients in a Palliative Care Unit

<p>From January 2015 to January 2017, we encountered five terminal cancer patients with implantable cardioverter defibrillators (ICDs) in the palliative care unit of our hospital. Due to delirium or dementia, four of these five patients did not have the decision-making capacity to stop their ICD. Although one patient was capable of making his own decisions, his family did not agree with the medical professional considering the patient’s decision. The families of all five patients made decisions on behalf of the patients. The procedure for stopping the ICD was first discussed with the families at 2–21 days prior to the patients’ deaths. The ICDs were stopped between 3 h and 11 days prior to the patients’ deaths, following the consent of the families, which was obtained after 1–5 consultations. Through these experiences, we became aware of the following problems with regard to stopping ICDs: (1) the lack of experience of medical professionals in decision-making, (2) the lack of recognition of medical professionals to the distress caused to patients by ICDs, (3) the psychological burden and time constraint of discussions, and (4) the lack of knowledge of ICDs among patients and their families. These problems need to be addresses as part of advance care planning for cancer patients. </p>

Initial experience of subcutaneous implantable cardioverter defibrillators in Singapore: a case series and review of the literature

Transvenous implantable cardioverter defibrillators are a type of implantable cardiac device. They are effective at reducing total and arrhythmic mortality in patients at risk of sudden cardiac death. Subcutaneous implantable cardioverter defibrillators (S-ICDs) are a new alternative that avoids the disadvantages of transvenous lead placement. In this case series, we report on the initial feasibility and safety of S-ICD implantation in Singapore.

Pacemakers and implantable cardioverter defibrillators - general and anesthetic considerations / Marcapassos e cardioversores desfibriladores implantáveis - considerações gerais e anestésicas / Marcapasos y desfibriladores automáticos implantables. Consideraciones generales y anestésicas

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

Marcapasso (MP) é um sistema que consiste em um gerador de impulso e eletrodo ou eletrodos que conduzem o impulso elétrico para o coração do paciente. Códigos de MP e cardioversor desfibrilador implantável (CDI) foram criados para descrever o tipo de MP ou CDI implantado. Indicações para a implantação de MP e CDI foram descritas pelo Colégio Americano de Cardiologistas. Alguns MPs têm interruptores de circuitos magneticamente operados incorporados, porém a aplicação magnética pode causar efeitos adversos graves; portanto, os dispositivos devem ser considerados programáveis, salvo conhecimento em contrário. Quando um paciente portador de dispositivo é submetido a qualquer procedimento (com ou sem anestesia), precauções especiais devem ser tomadas, incluindo história/exame físico focados; perguntas sobre o MP antes e após o procedimento, uso de medicamentos de emergência/estimulação e desfibrilação temporárias; reprogramação do MP e desabilitação de certas funções, caso necessário; monitoração dos distúrbios metabólicos e eletrolíticos e evitar certos medicamentos e equipamentos que podem interferir na função do MP. Se houver previsão de interações com o dispositivo, considerar a suspensão do procedimento até que a fonte de interferência tenha sido eliminada ou controlada e todas as medidas corretivas devem ser tomadas para garantir o funcionamento adequado do MP. Após o procedimento, frequência e ritmo cardíacos devem ser monitorados continuamente, medicamentos e equipamentos de emergência devem ser mantidos de prontidão e pode ser necessário consultar um cardiologista ou serviço de MP-CDI.

El marcapasos (MP) es un sistema que consiste en un generador de impulso y un electrodo o electrodos que conducen el impulso eléctrico hacia el corazón del paciente. Se han creado códigos de MP y de desfibrilador automático implantables para describir el tipo de cada uno. El Colegio Norteamericano de Cardiólogos han descrito indicaciones para la implantación de MP y de desfibrilador automático implantable. Algunos MP tienen interruptores de circuitos magnéticos incorporados, sin embargo, la aplicación magnética puede causar efectos adversos graves; por tanto, los dispositivos deben ser considerados programables, salvo que se tenga un conocimiento diferente. Cuando un paciente portador de dispositivo se somete a cualquier procedimiento (con o sin anestesia), se deben tomar precauciones especiales, incluyendo historial/examen físico dirigidos; preguntas sobre el MP antes y después del procedimiento, uso de medicamentos de urgencia/estimulación y desfibrilación temporales; reprogramación del MP e inhabilitación de ciertas funciones del mismo, si fuere preciso; monitorización de los trastornos metabólicos y electrolíticos y evitar ciertos medicamentos y equipos que puedan interferir con la función del MP. Si hay alguna previsión de interacción con el dispositivo, considerar la suspensión del procedimiento hasta que la fuente de la interferencia haya sido eliminada o controlada. Se deben tomar todas las medidas correctivas para garantizar el funcionamiento adecuado del MP. Después del procedimiento, la frecuencia y el ritmo cardíacos deben ser monitorizados continuamente, y deben estar preparados los medicamentos y equipos de urgencia; y si fuera necesario, consultar con un cardiólogo o con el servicio de MP- desfibrilador automático implantable.

Efficacy of cognitive behavioral therapy in reducing psychiatric symptoms in patients with implantable cardioverter defibrillator: an integrative review

This article is a systematic review of the available literature on the benefits that cognitive behavioral therapy (CBT) offers patients with implanted cardioverter defibrillators (ICDs) and confirms its effectiveness. After receiving the device, some patients fear that it will malfunction, or they remain in a constant state of tension due to sudden electrical discharges and develop symptoms of anxiety and depression. A search with the key words “anxiety”, “depression”, “implantable cardioverter”, “cognitive behavioral therapy” and “psychotherapy” was carried out. The search was conducted in early January 2013. Sources for the search were ISI Web of Knowledge, PubMed, and PsycINFO. A total of 224 articles were retrieved: 155 from PubMed, 69 from ISI Web of Knowledge. Of these, 16 were written in a foreign language and 47 were duplicates, leaving 161 references for analysis of the abstracts. A total of 19 articles were eliminated after analysis of the abstracts, 13 were eliminated after full-text reading, and 11 articles were selected for the review. The collection of articles for literature review covered studies conducted over a period of 13 years (1998-2011), and, according to methodological design, there were 1 cross-sectional study, 1 prospective observational study, 2 clinical trials, 4 case-control studies, and 3 case studies. The criterion used for selection of the 11 articles was the effectiveness of the intervention of CBT to decrease anxiety and depression in patients with ICD, expressed as a ratio. The research indicated that CBT has been effective in the treatment of ICD patients with depressive and anxiety symptoms. Research also showed that young women represented a risk group, for which further study is needed. Because the number of references on this theme was small, further studies should be carried out.

Thrombosis in the Left Ventricle after Implantable Cardioverter-Defibrillator Implantation: A Rare Cause of Systemic Thromboembolism / 대한구급학회지

This report describes a case of systemic thromboembolism caused by left ventricular (LV) thrombosis that developed after placement of an implantable cardioverter-defibrillator (ICD). A 27-year-old male patient was diagnosed with idiopathic dilated cardiomyopathy and ventricular tachycardia, and underwent ICD implantation for the primary prevention of sudden cardiac death. Two weeks after ICD implantation, the patient experienced renal infarction. Transthoracic echocardiography revealed a mobile thrombus at the LV apex, and automated function imaging demonstrated deteriorated LV function after ICD implantation. The RV was not placed by ICD and the mechanical force which was occurred by ICD that led to induced dyssynchronous motion of the LV apex may have resulted in a systemic thromboembolism.

Magnets and implantable cardioverter defibrillators: What's the problem.

A growing number of surgical patients present to the operating room with implantable cardioverter defibrillators (ICD). Peri-operative care of these patients dictates that ICD function be suspended for many surgical procedures to avoid inappropriate, and possibly harmful, ICD therapy triggered by electromagnetic interference (EMI). An alternative to reprogramming the ICD is the use of a magnet to temporarily suspend its function. However, this approach is not without complications. We report a case where magnet use failed to inhibit ICD sensing of EMI, and a shock was delivered to the patient. Measures to decrease EMI, controversies regarding magnet use, and expert recommendations are discussed.

Reuse of Cardiac Rhythm Control Devices: A Review.

Cardiac rhythm control devices i.e. pacemakers, implantable cardioverter-defibrillators (ICDs) and biventricular pacemakers are at times lifesaving treatment and prevention of arrhythmia. But, despite definite indications, many people in the developing countries cannot afford these devices due to high cost, and succumb to premature death. On the other hand, after implantation, pacemakers and ICDs are sometimes underutilized because of premature explantation due to death of the recipient, device infection, or upgradation, leaving a considerable extent of serviceable battery life unused. Majority of these explanted devices are simply thrown away. Though made for single use, a growing body of evidence indicates the safety, efficacy and feasibility of reimplantation of the prematurely explanted devices in patient in need who is otherwise unable to afford a new one. Patients, physicians, morticians, and even the general public support the idea of device donation and recycling. A number of organizations around the world have engaged themselves in this benevolent effort, and t he feasibility of device reutilization programme has already been established. However, some logistic, legal and ethical concerns are yet to be solved. The statutory bodies and professional organizations should address the issue of device recycling to solve the unsolved issues and formulate standard practice guidelines. In that case, such medical wastes may turn into invaluable resources, and help ensuring equitable medical care throughout the world.

A Case of Riata(R) Dual Coil Defibrillator Lead Failure in a Patient with Ventricular Fibrillation

A 50-year-old man, who underwent a procedure for an implantable cardioverter defibrillator (ICD), visited the outpatient department of our clinic after suffering multiple ICD shocks. The ICD interrogation revealed recurrent shock due to a high frequency of noise that is sensed by the device as ventricular fibrillation. Chest radiography revealed a significant split in the insulation of the lead allowing the inner wire to protrude. We considered the removal of the failed lead, but the removal of ICD lead is potentially a high risk procedure, so we cut and capped a proximal part of the failed lead and inserted a new lead. This is the first report of a St. Jude Riata(R) dual coil defibrillator lead failure with clinical and radiologic evidence of a defect in lead insulation in Korea.

Terapia posimplante de cardiodesfibrilador como prevención primaria y secundaria de muerte súbita en la Fundación Abood Shaio: seguimiento a un año / Therapy after to the implant of cardioverter-defi brillator in the primary and secundary prevention of sudden death during the fi rst year of follow up in the a clinic of fourth level of complexity

Introducción: el implante de cardiodesfi briladores ha cambiado el pronóstico en la prevención primaria y secundaria en paciente con muerte súbita. Hay sufi ciente evidencia que soporta que las terapias del cardiodesfi brilador, antitaquicardia y choques; tienen impacto sobre la morbimortalidad de los pacientes portadores del mismo, además del efecto proarritmogénico. Objetivo: está por determinar cuál es la incidencia de terapias apropiadas e inapropiadas en nuestra población de pacientes portadores de cardiodesfi brilador por prevención primaria y secundaria de muerte súbita. Materiales y métodos: se describe una serie de casos de pacientes a quienes se les implantó un cardiodesfi brilador como prevención primaria y secundaria de muerte súbita en una institución de cuarto nivel de complejidad. Resultados: la incidencia de terapia delcardiodesfi brilador implantable posimplante en pacientes con prevención primaria y secundaria de muerte súbita al primer año de seguimiento fue 44%. La incidencia de terapia apropiada del cardiodesfi brilador posimplante en pacientes con prevención primaria de muerte súbita al primer año de seguimiento fue 26,3%.La incidencia de terapia apropiada del cardiodesfi brilador posimplante en pacientes con prevención secundariade muerte súbita al primer año de seguimiento fue 53%. La mitad de los pacientes posimplante decardiodesfi brilador implantable como prevención primaria o secundaria presentaron terapias apropiadasdurante el seguimiento a un año. Los pacientes que presentaron terapias inapropiadas durante el año deseguimiento posterior al primoimplante de cardiodesfi brilador fueron 36%. Conclusiones: la terapia posterioral implante de cardiodesfi brilador se presento casi en la mitad de los pacientes, siendo más frecuente enprevención secundaria. Estos episodios se pueden presentar en diferentes patologías y pueden ser apropiadose inapropiados. Las complicaciones del procedimiento pueden ser agudas y crónicas.

The implant of Cardioverter-Defi brillator has changes the pronostic in the primary and secondary prevention in the patients with suden death. There are a lot of evidence that supports that the therapies of the CDI (antitachycardia and shocks) have impact on the morbimortality of the patients with Implantable Cardioverter-Defi brillators, besides the effect proarritmogenic. Objective: It is for determining which is the incidence of appropriate and inappropriate therapies in our population of patients with Implantable Cardioverter-Defi brillators for primary and secondary prevention of sudden death. Materials and Methods: we describe a case series of patients with cardioverter-Defi brillator as the primary and secondary prevention of sudden death in a clinic of fourth level of complexity. Results: the incidence of therapy of the Implantable Cardioverter-Defi brillators after implant in patients with primary and secondary prevention of sudden death to the fi rst year of follow-up was 44%. The incidence of apropiate therapy of the Implantable Cardioverter-Defi brillators after implant in patients with primary prevention of sudden death to the fi rst year of follow-up was the 26.3%.

The incidence of apropiate therapy of the Implantable Cardioverter-Defi brillators after implant in patients with secondary prevention of sudden death to the fi rst year of follow-up was the 53%. The half of the patients with Implantable Cardioverter-Defi brillators afterimpant for primary prevention or secondary had apropiate therapies during the fi rst year of follow-up. 36% of the patients presented inappropriate therapies during the year of follow-up after fi rst implat of the Implantable Cardioverter-Defi brillators. Conclusions: the therapies after to the implant of cardioverter-Defi brillator were near to the half of the patients, being more frecuent in the secundary prevention. These events may be present in the different pathologies, and to be apropiate and inapropiate. The complications of procedure may be acutes and chronics.

Implantable Cardioverter-Defibrillator Lead Extraction by Conventional Traction and Counter-Traction Technique

A 46-year-old man presented to our institution with inappropriate implantable cardioverter-defibrillator (ICD) shock delivery. The ICD (single chamber, dual shock coils) was implanted for sustained monomorphic ventricular tachycardia with unstable hemodynamics and underlying systolic left ventricular dysfunction. ICD interrogation revealed recurrent episodes of ICD shock due to noise sensing and increased impedance of right ventricular-lead. With the impression of lead fracture, ICD lead extraction was performed. The fractured ICD lead was completely removed by traction of locking stylet and counter-traction of polypropylene dilator sheath. A new lead was inserted and the patient was discharged without complications after 2 days. To our knowledge, this is the first report on ICD lead extraction by conventional traction and counter-traction technique in Korea.

Prevalence of Echocardiographic Features Suggesting Cardiac Sarcoidosis in Patients With Pacemaker or Implantable Cardiac Defibrillator

BACKGROUND AND OBJECTIVES: Basal septal thinning or localized aneurysmal dilatation without coronary artery disease has been described as a characteristic finding suggestive of cardiac sarcoidosis. We sought to assess the prevalence of this characteristic echocardiographic finding in patients with pacemaker (PM) or implantable cardiac defibrillator (ICD). SUBJECTS AND METHODS: Echocardiography of patients who received PM or ICD were retrospectively analyzed. Patients with marked thinning and akinesia confined to the basal septum (type 1), or posterolateral wall resulting in localized aneurysmal outward bulging (type 2) without history of myocardial infarction or significant coronary stenosis were included for analysis. RESULTS: Among 1,357 consecutive patients, 21 exhibited suggestive echocardiographic findings (type 1/2=15/6) with a mean ejection fraction of 37+/-11%. The prevalence was 1.2% in the PM group and 4.0% in the ICD group. Only 3 patients showed histologically confirmable sarcoidosis in lymph nodes, lung and heart, respectively. Endomyocardial biopsy was attempted in 6 patients, but failed to demonstrate sarcoidosis. The 1-, 2-, 4- and 6-year clinical events (death, cardiac transplantation and hospital admission)-free survival rates were 100%, 85.7+/-7.6%, 75.0+/-9.7% and 48.6+/-12.4%, respectively. During follow-up, two patients with PM underwent ICD implantation, and another underwent heart transplantation. CONCLUSION: Prevalence of echocardiographic features suggesting prevalence of cardiac sarcoidosis is low in patients who underwent device implantation. However, considering the very low yield of endomyocardial biopsy and the rare extracardiac manifestations in cardiac sarcoidosis, characteristic echocardiographic findings could be an adjunctive diagnostic criterion in these patients.

Electrical Storms in Patients with an Implantable Cardioverter Defibrillator

PURPOSE: In some patients with an implantable cardioverter defibrillator (ICD), multiple episodes of electrical storm (ES) can occur. We assessed the prevalence, features, and predictors of ES in patients with ICD. MATERIALS AND METHODS: Eighty-five patients with an ICD were analyzed. ES was defined as the occurrence of two or more ventricular tachyarrhythmias within 24 hours. RESULTS: Twenty-six patients experienced at least one ES episode, and 16 patients experienced two or more ES episodes. The first ES occurred 209 +/- 277 days after ICD implantation. In most ES cases, the index arrhythmia was ventricular tachycardia (65%). There were no obvious etiologic factors at the onset of most ES episodes (57%). More patients with a structurally normal heart (p = 0.043) or ventricular fibrillation (VF) as the index arrhythmia (p = 0.017) were in the ES-free group. Kaplan-Meier estimates and a log-rank test showed that patients with nonischemic dilated cardiomyopathy (DCMP) (log-rank test, p = 0.016) or with left ventricular ejection fraction < 35% (p = 0.032) were more likely to experience ES, and that patients with VF (p = 0.047) were less affected by ES. Cox proportional hazard regression analysis showed that nonischemic DCMP correlated with a greater probability of ES (hazard ratio, 3.71; 95% confidence interval, 1.16-11.85; p = 0.027). CONCLUSION: ES is a common and recurrent event in patients with an ICD. Nonischemic DCMP is an independent predictor of ES. Patients with VF or with a structurally normal heart are less likely to experience ES.