Efficacy of implantable cardioverter defibrillators in young patients with catecholaminergic polymorphic ventricular tachycardia: success depends on substrate. Circulation. Arrhythmia and electrophysiology Miyake, C. Y., Webster, G., Czosek, R. J., Kantoch, M. J., Dubin, A. M., Avasarala, K., Atallah, J. 2013; 6 (3): 579-587

Abstract

BACKGROUND: -The effectiveness of implantable cardioverter-defibrillator (ICD) therapy for the management of catecholaminergic polymorphic ventricular tachycardia (CPVT) in young patients is not known. ICD discharges are not always effective and inappropriate discharges are common, both resulting in morbidity and mortality. METHODS AND RESULTS: -This is a multicenter, retrospective review of young patients with CPVT and ICDs from 5 centers. ICD discharges were evaluated to determine arrhythmia mechanism, appropriateness, efficacy of therapy, and complications. A total of 24 patients were included. Median (IQR) ages at onset of CPVT symptoms and ICD implant were 10.6 (5.0 - 13.8) years and 13.7 (10.7 - 16.3) years respectively. Fourteen patients received 140 shocks. Ten patients (42%) experienced 75 appropriate shocks and 11 patients (46%) received 65 inappropriate shocks. On actuarial analysis, freedom from appropriate shock at 1 year after ICD implant was 75%. Of appropriate shocks, only 43 (57%) demonstrated successful primary termination. All successful appropriate ICD discharges were for ventricular fibrillation (VF). No episodes of polymorphic ventricular tachycardia or bidirectional VT demonstrated successful primary termination. The adjusted mean (95% CI) cycle length of successful discharges was significantly shorter than unsuccessful discharges (168 (152-184) msec vs. 245 (229-262) msec, adjusted p=0.002). Electrical storm occurred in 29% (4/14) and induction of more malignant ventricular arrhythmias in 36% (5/14). There were no deaths. CONCLUSIONS: -ICD efficacy in CPVT depends on arrhythmia mechanism. Episodes of VF were uniformly successfully treated whereas polymorphic and bidirectional VT did not demonstrate successful primary termination. Inappropriate shocks, electrical storm and ICD complications were common.

View details for DOI 10.1161/CIRCEP.113.000170

View details for PubMedID 23667268