Comparison of the Outcome of Patients Protected by the Wearable Cardioverter Defibrillator (WCD) for <90 Wear Days versus ≥90 Wear Days.

BACKGROUND/AIM: The wearable cardioverter/defibrillator (WCD) is recommended to prevent sudden cardiac death (SCD). Guidelines suggest a 90 days' period, but prolongation of WCD wear time until increasing the ejection fraction (≥35%) might be suggested. PATIENTS AND METHODS: A cohort of 153 patients with prescribed WCD were divided into two groups: A <90 wear days' group (n=112) vs. ≥90 wear days' group (n=41) and followed. RESULTS: In the first group, WCD shock occurred in 3.6% of patients, 47.3% improved in left ventricular ejection fraction (LVEF) after 3 months, and 37.5% had a cardiac implantable electronic device (CIED) implantation with appropriate implantable cardioverter defibrillator (ICD) shock events occurring in 6 patients. Two of these patients already received WCD shock therapy due to ventricular fibrillation. A 20.5% improved in LVEF after 6-12 months, but 73% were already implanted with ICD. In the second group, 4.9% received WCD shock, 34.1% improved in LVEF after 3 months, 48.8% were implanted with ICD, and 2 had ICD shocks during follow up time. LVEF improvement after 6-12 months occurred in 26.8%. ICD implantation was prevented in 7.3% of patients due to LVEF recovery. CONCLUSION: Prolonging wearing days of WCD may reduce the number of inappropriate ICD implantation.

The Wearable Cardioverter-Defibrillator: Experience in 153 Patients and a Long-Term Follow-Up.

Background: The wearable cardioverter-defibrillator (WCD) is available for patients at high risk for sudden cardiac death (SCD) when immediate implantable cardioverter-defibrillator (ICD) implantation is not possible or indicated. Patient selection remains challenging especially in primary prevention. Long-term data on these patients is still lacking. METHODS: 153 patients were included in this study. They were prescribed the WCD between April 2012 and March 2019 at the University Medical Center, Mannheim, Germany. The mean follow-up period was 36.2 ± 15.6 months. Outcome data, including all-cause mortality, were analyzed by disease etiology and ICD implantation following WCD use. RESULTS: We analyzed 56 patients with ischemic cardiomyopathy, 70 patients with non-ischemic cardiomyopathy, 16 patients with prior need for ICD/CRT-D (device for cardiac resynchronization therapy with defibrillator) explanation, 8 patients with acute myocarditis and 3 patients with congenital diseases. 58% of the patients did not need ICD/CRT-D implantation after WCD use. 4% of all patients suffered from appropriate WCD shocks. 2 of these patients (33%) experienced appropriate ICD shocks after implantation due to ventricular tachyarrhythmias. Long-term follow-up shows a good overall survival. All-cause mortality was 10%. There was no significant difference between patients with or without subsequent ICD implantation (p = 0.48). Patients with ischemic cardiomyopathy numerically showed a higher long-term mortality than patients with non-ischemic cardiomyopathy (14% vs. 6%, p = 0.13) and received significantly more ICD shocks after implantation (10% of ischemic cardiomyopathy (ICM) patients versus 3% of non-ischemic cardiomyopathy (NICM) patients, p = 0.04). All patients with ventricular tachyarrhythmias during WCD use or after ICD implantation survived the follow-up period. CONCLUSION: Following WCD use, ICD implantation could be avoided in 58% of patients. Long-term follow-up shows good overall survival. The majority of all patients did not suffer from WCD shocks nor did receive ICD shocks after subsequent implantation. Patient selection regarding predictive conditions on long-term risk of ventricular tachyarrhythmias needs further risk stratification.