Implantable cardioverter-defibrillator use in catecholaminergic polymorphic ventricular tachycardia: A systematic review

Background: The implantable cardioverter-defibrillator (ICD) may be associated with a high risk of complications in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT). However, ICDs in this population have not been systematically evaluated. Objective: The purpose of this study was to characterize the use and outcomes of ICDs in CPVT. Methods: We conducted a systematic review using Embase, MEDLINE, PubMed, and Google Scholar to identify studies that included patients with CPVT who had an ICD. Results: Fifty-three studies describing 1429 patients with CPVT were included. In total, 503 patients (35.2%) had an ICD (median age 15.0 years; interquartile range 11.0–21.0 years). Among ICD recipients with a reported medication status, 96.7% were prescribed β-blockers and 13.2% flecainide. Sympathetic denervation was performed in 23.2%. Nearly half of patients received an ICD for primary prevention (47.3%), and 12.8% were prescribed optimal antiarrhythmic therapy. During follow-up, 40.1% had ≥1 appropriate shock, 20.8% experienced ≥1 inappropriate shock, 19.6% had electrical storm, and 7 patients (1.4%) died. An ICD-associated electrical storm was implicated in 4 deaths. Additional complications such as lead failure, endocarditis, or surgical revisions were observed in 96 of 296 patients (32.4%). A subanalysis of the 10 studies encompassing 330 patients with the most detailed ICD-related data showed similar trends. Conclusion: In this population with CPVT, ICDs were common and associated with a high burden of shocks and complications. The reliance on primary prevention ICDs, and poor uptake of adjuvant antiarrhythmic therapies, suggests that improved adherence to guideline-directed management could reduce ICD use and harm.