Predictors of ventricular tachyarrhythmia in patients with a wearable cardioverter defibrillator: an international multicenter registry.

Background and aims: Wearable cardioverter defibrillator (WCD) can protect patients from sudden cardiac death due to ventricular tachyarrhythmias and serve as a bridge to decision of definite defibrillator implantation. The aim of this analysis from an international, multicenter WCD registry was to identify predictors of sustained ventricular tachycardia (VT) and/or ventricular fibrillation (VF) in this population.

Methods: One thousand six hundred seventy-five patients with WCD were included in a multicenter registry from 9 European centers, with a median follow-up of 440 days (IQR 120-893). The primary study end point was the occurrence of sustained VT/VF.

Results: Sustained VT was detected by WCD in 5.4% and VF in 0.9% of all patients. Of the 30.3% of patients receiving ICD implantation during follow-up, sustained VT was recorded in 9.3% and VF in 2.6%. Non-ischemic cardiomyopathy (HR 0.5, p < 0.001), and medication with angiotensin-converting enzyme inhibitors (HR 0.7, p = 0.027) and aldosterone antagonists (HR 0.7, p = 0.005) were associated with a significantly lower risk of VT/VF.

Conclusions: Patients who received WCD due to a transient increased risk of sudden cardiac death have a comparatively lower risk of VT/VF in the presence of non-ischemic cardiomyopathy. Of note, optimal medical treatment for heart failure not only results in an improvement in left ventricular ejection fraction but also in a reduction in the risk for VT/VF.