Long-term Results for Sudden Cardiac Death Prevention of Implantable Cardioverter-defibrillator in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy / 中国循环杂志

Objective:Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare inherited cardiomyopathy,which may cause frequent ventricular arrhythmia or even sudden cardiac death (SCD).We observed the long-term follow-up result of high risk ARVC patients received an implantable cardioverter-defibrillator(ICD).Methods:We retrospectively collected ARVC patients with ICD who were treated in our hospital from 1996-12 to 2015-09 for their in-hospital and clinical records and conducted follow-up study.Results:A total of 39 ARVC patients were enrolled including 32 (82.1％) males,the mean age at diagnosis was (42.1±14.8) years and 33 (84.6％) patients suffered from persistent ventricular tachycardia (VT) or ventricular fibrillation (VF) prior to ICD therapy.The median follow-up time was 48.6 (32.3-73.3) months and 7 (7.7％) patients died during that period including 1 sudden death,1 heart failure and 1 cerebral infarction.28 (71.8％) patients received 540 appropriate ICD interventions,5 (12.8％) of them received the first appropriate ICD intervention more than 2 years after initial implantation procedure.12 (30.8％) patients experienced electrical storm and 7 (17.9％) of them with electrical storm more than 2 years after initial implantation procedure.The patients without broad precordial T wave inversion (TWI ≥V1～3) had a shorter eventfree survival period (HR=0.39,95％ CI 0.16-0.96).The application rates of antiarrhythmic drugs and radiofrequency catheter ablation before ICD therapy were similar in patients with or without appropriate ICD intervention,P＞0.05.Conclusion:High risk ARVC patients have frequent ventricular arrhythmia,ICD therapy could effectively stop VT/VF,which was the most reliable method to prevent sudden cardiac death.

Long-term Results for Sudden Cardiac Death Prevention of Implantable Cardioverter-defibrillator in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy / 中国循环杂志

Objective:Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare inherited cardiomyopathy,which may cause frequent ventricular arrhythmia or even sudden cardiac death (SCD).We observed the long-term follow-up result of high risk ARVC patients received an implantable cardioverter-defibrillator(ICD).Methods:We retrospectively collected ARVC patients with ICD who were treated in our hospital from 1996-12 to 2015-09 for their in-hospital and clinical records and conducted follow-up study.Results:A total of 39 ARVC patients were enrolled including 32 (82.1％) males,the mean age at diagnosis was (42.1±14.8) years and 33 (84.6％) patients suffered from persistent ventricular tachycardia (VT) or ventricular fibrillation (VF) prior to ICD therapy.The median follow-up time was 48.6 (32.3-73.3) months and 7 (7.7％) patients died during that period including 1 sudden death,1 heart failure and 1 cerebral infarction.28 (71.8％) patients received 540 appropriate ICD interventions,5 (12.8％) of them received the first appropriate ICD intervention more than 2 years after initial implantation procedure.12 (30.8％) patients experienced electrical storm and 7 (17.9％) of them with electrical storm more than 2 years after initial implantation procedure.The patients without broad precordial T wave inversion (TWI ≥V1～3) had a shorter eventfree survival period (HR=0.39,95％ CI 0.16-0.96).The application rates of antiarrhythmic drugs and radiofrequency catheter ablation before ICD therapy were similar in patients with or without appropriate ICD intervention,P＞0.05.Conclusion:High risk ARVC patients have frequent ventricular arrhythmia,ICD therapy could effectively stop VT/VF,which was the most reliable method to prevent sudden cardiac death.

Tachyarrhythmia Cycle Length in Appropriate versus Inappropriate Defibrillator Shocks in Brugada Syndrome, Early Repolarization Syndrome, or Idiopathic Ventricular Fibrillation

BACKGROUND AND OBJECTIVES: Implantable cardioverter–defibrillators (ICDs) are indicated in patients with Brugada syndrome (BS), early repolarization syndrome (ERS), or idiopathic ventricular fibrillation (IVF) who are at high risk for sudden cardiac death. The optimal ICD programming for reducing inappropriate shocks in these patients remains to be determined. We investigated the difference in the mean cycle length of tachyarrhythmias that activated either appropriate or inappropriate ICD shocks in these three patient groups to determine the optimal ventricular fibrillation (VF) zone for minimizing inappropriate ICD shocks. SUBJECTS AND METHODS: We selected 41 patients (35 men) (mean age±standard deviation=42.6±13.0 year) who received ICD shocks between April 1996 and April 2014 to treat BS (n=24), ERS (n=9), or IVF (n=8). Clinical and ICD interrogation data were retrospectively collected and analyzed for all events with ICD shocks. RESULTS: Of the 244 episodes, 180 (73.8%) shocks were appropriate and 64 (26.2%) were inappropriate. The mean cycle lengths of the tachyarrhythmias that activated appropriate and inappropriate shocks were 178.9±28.7 ms and 284.8±24.4 ms, respectively (p<0.001). The cutoff value with the highest sensitivity and specificity for discriminating between appropriate and inappropriate shocks was 235 ms (sensitivity, 98.4%; specificity, 95.6%). When we programmed a single VF zone of ≤270 ms, inappropriate ICD shocks were reduced by 70.5% and appropriate shocks were missed in 1.7% of these patients. CONCLUSION: Programming of a single VF zone of ≤270 ms in patients with BS, ERS, or IVF could reduce inappropriate ICD shocks, with a low risk of missing appropriate shocks.

Cardiodesfibriladores implantables. Diecinueve años de experienciaen un centro de nuestro país.Estudio retrospectivo en el seno de una cohorte prospectiva. Supervivencia de pacientes, dispositivos y tiempo libre de eventos en 182 pacientes portadores de cardiodesfibrilador implantable / Implantable defibrillators. Nineteen years of experience a center of our country. A retrospective study within a prospective cohort. Survival of patients, devices and event-free time in 182 patients with implantable cardioverter-defibrillators

Introducción: el desfibrilador automático implantable (DAI) mejora la supervivencia en pacientes con riesgo de muerte súbita cardíaca (MSC). Aunque en nuestro país se utiliza desde hace 19 años, existen escasos datos de seguimiento acerca de su eficacia. Material y método: cohorte prospectiva observacional de 182 pacientes con primoimplante de DAI reclutada en el período2/1993 - 6/2011, que se cerró el 31/6/2012. Edad media: 57 ± 14 años, 83% hombres, 37% fracción de eyección del ventrículo izquierdo (FEVI)<30%, 51% portadores de cardiopatía isquémica y 73% indicación en prevención secundariade MSC. Eventos incidentes considerados: muerte, recambio y primer evento. La probabilidad acumulada de supervivencia se estimó a través de un modelo de Kaplan-Meier (KM), utilizando el SPSS V17.0. Se calcularon las tasas de incidenciaen personas-año-1(IC95%) del primer evento según las respuestas del DAI. Resultados: supervivencia de pacientes: luego de un seguimiento de 988 años-paciente, (mediana: 4 años), la probabilidad de supervivencia (KM, IC95%) al cierre fue de 30% (5%-55%). Vida útil del dispositivo: luego de 619 años-paciente de seguimiento (mediana: 3,7 años), la probabilidad de recambio (KM, IC95%) fue de 2,4% (2%-7%). Supervivencia libre deeventos: luego de 428 años-paciente de seguimiento (mediana: 1,3 años), la probabilidad acumulada libre de primer evento (KM, IC95%) fue de 10% (1%-19%). Tasas de incidencia de choques y terapias antitaquicardia apropiadas 0,20(0,16-0,24) e inapropiados 0,07 (0,04-0,10). Conclusión: el seguimiento prolongado de pacientes portadores de DAI mostró probabilidades de supervivencia de pacientes, vida útil de los dispositivos y tiempo libre de eventos aceptables.

Introduction: Implantable cardioverter defibrillator (ICD) has been reported to improve survival in patients at risk for sudden cardiac death (SCD). There is little follow up data in patients with ICD implant in Uruguay, although it has been used for 19 years already.Methods: A prospective observational cohort of 182 patients with first ICD implant was enrolled between February/1993 and June/2011. The follow up period was closed on 31/06/2012. Clinical characteristics: average age 57 ± 14 years, 83% men, 37% with left ventricular ejection fraction < 30%, coronary artery disease: 51% and secondary prevention ICD implant: 73%. Death, device replacement and first event were considered as end points. Survival curves were calculated by the Kaplan-Meier method (KM), using the SPSS V17.0. Incidence rates of first events were calculated in person-year-1 (IC95%) according to the ICD recorded therapies.Results: Overall survival: after a follow up of 988 years-patient (median: 4 years), the cumulative probability of survival (KM, IC95%) was 30% (% 5-55%). Device’s life time: after a follow up of 619 years-patient (median: 3,7 years) the cumulative probability of replacement (KM, IC95%) was 2,4% (2-7%). Events free survival: after a follow up of 428 years-patient (median: 1,3 years), the cumulative probability of events free survival (KM, IC95%) was 10% (1-19%). The incidence rate of appropriate shocks and antitachycardia therapy was 0,20 (0,16-0,24) and the inappropriate one was 0,07 (0,04-0,10).Conclusion: An acceptable probability of patients survival and device’s life time as well as an acceptable events free survival were observed in this cohort over a long follow up period.