Appropriate ICD Therapy in Patients With Idiopathic Dilated Cardiomyopathy Long-Term Follow-Up

Abstract

SUMMARYThe implantable cardioverter defibrillator (ICD) has proved effective in preventing sudden death and decreasing mortality in randomised secondary prevention trials. Some nonrandomised studies have reported different incidences and predictors of appropriate ICD therapy in patients with idiopathic dilated cardiomyopathy (DCM). The antiarrhythmic and other medical therapies were different between the published studies and it was reported that not using beta-blockers was a predictor of appropriate ICD therapy. In the present study, we report on our long-term experience with ICD therapy in patients with DCM, the majority of whom were treated with beta-blockers and amiodarone.The study population consisted of 25 patients with DCM who underwent initial transvenous ICD implantation between December 1995 and May 2005. Indications for ICD implantation were monomorphic sustained ventricular tachycardia (VT) in 16 patients (64%), cardiac arrest in 8 patients (32%), and syncope plus inducible VT in one patient. Twenty-four patients underwent an electrophysiologic study (EPS). In 18 patients, the ICDs were programmed to only shocks and in 7 patients an additional antitachycardia pacing program was performed. One patient was lost to follow-up and 24 patients were followed-up primarily in our ICD pacemaker outpatient clinic. Appropriate ICD therapy was defined as antitachycardia pacing therapy or shock for tachyarrhythmia determined by evaluation of the clinical information and by device diagnostics to be either ventricular fibrillation or ventricular tachycardia.The mean follow-up was 39.29 ± 30.59 months after ICD implantation. At follow-up, 17 patients were using a beta-blocker and 16 patients amiodarone. Appropriate ICD therapy was observed in 14 patients (58%). The detected arrhythmias were VT in 12 patients, ventricular fibrillation (VF) in one, and VT and VF in one patient. The time to first ICD therapy was 15.93 ± 18.45 (range, 1-74) months. Using the Kaplan-Meier method, the percent survival free of appropriate ICD therapy was 82%, 72%, 66%, and 55% at 1, 2, 3, and 4 years follow-up, respectively. The clinical, echocardiographic, and electrophysiologic characteristics did not differ between those who did and did not receive appropriate ICD therapy. However, the mean QRS duration was significantly longer in patients who received appropriate ICD therapies. Cox regression analysis did not reveal any factors that predicted appropriate ICD therapy. Five patients (21%) died during follow-up. FourFrom the

Primary and Secondary Prevention of Ventricular Arrhythmias in Dilated Cardiomyopathy Nonsustained, Sustained, and Incessant

“…[13][14][15][16] Our relatively high incidence of adequate ICD intervention may be explained in part by the high number of nsVT in our primary preventive ICD recipients. Although in this study nsVT were not predictive for arrhythmias there might have been a selection bias due to the small sample rate.…”

Peer Review #3 of "Comparison of ventricular tachyarrhythmia recurrence between ischemic cardiomyopathy and dilated cardiomyopathy: a retrospective study (v0.1)"

“…There were no differences in the cardiovascular mortality and all-cause mortality between the ICM patients and DCM patients receiving ICD for secondary prevention. After adequate medical treatment for at least half a year half-year adequate medical treatment, a higher prevalence of recurrent ventricular tachyarrhythmia was noted in the patients with LVEDV > 158 mL One study reported that around 50 % of recurrent VT/VF events developed in DCM patients with ICD implantation for primary prevention and secondary prevention, and the time between implantation and first appropriate therapy was similar between primary and secondary prevention patients (Karaoguz et al, 2006;Meyer et al, 2009). LV dilatation has been reported to be as a major negative prognostic marker in patients with HF (Frigerio et al, 2005) and indicates a diseased heart with a high posibility of recurrent ventricular tachyarrhythmia.…”

Orage rythmique chez un patient porteur d’une cardiomyopathie dilatée et un défibrillateur automatique implantable (DAI)

“…Concernant les antitarythmiques, ceux de la classe III de la classification de Vaughan Williams (amiodarone, sotalol, dofétilide, azimilide) sont particulièrement recommandés car ils ont des effets bénéfiques sur les fréquents chocs induits par les DAI chez des patients qui en sont porteurs [7, 8], tel était le cas de notre patient. Aussi, les antiarythmiquessont considérés comme nécessaires chez plus de 70% des patients porteurs de DAI pour plusieurs raisons [7]: ils permettent de prévenir et traiter les épisodes de tachyarythmies atriales (la fibrillation atriale étant l’arythmie la plus fréquente, survenant chez plus de 20% de patients porteurs d’un DAI) [7]; les antiarythmiques contribuent à diminuer la fréquence des chocs des DAI; enfin, ils permettent de juguler les arythmies ventriculaires résultant des traitements par stimulation antitachycardique (ATP) délivrés par les DAI.…”