Variability in Prescribing Patterns of Wearable Cardiac Defibrillators: Current Data, Guidelines, Challenges, and Controversies

Wearable cardioverter-defibrillators (WCDs) offer a non-invasive, temporary safeguard against sudden cardiac death in patients with transient high-risk conditions, but real-world prescribing is highly variable due to inconsistent evidence of benefit. This review examines current WCD evidence and guideline recommendations, highlighting recent clinical findings, international guideline discrepancies, health economic data, and controversies underlying heterogeneous prescribing practices.

Observational studies and meta-analyses show that WCDs effectively terminate malignant arrhythmias and that arrhythmic death during WCD use is rare (~ 0.7% over 3 months). Approximately 5% of patients receive appropriate WCD shocks within 3 months. However, the VEST randomized trial did not demonstrate a significant reduction in arrhythmic mortality, likely due in part to low patient adherence (median 18 h/day). Post-hoc analyses of VEST suggested potential mortality reduction with better compliance. Reflecting the evidence gap, U.S. guidelines (2017) granted WCD a Class IIa/IIb role in several transient high-risk scenarios, whereas recent European guidelines (2021–2022) are more restrictive after VEST’s neutral results. Modeling studies indicate WCD use can be cost-effective in select high-risk populations, but the device’s high cost ($3,734/month; ~$223k per shock) raises concerns for broader use.

WCD prescribing remains highly heterogeneous worldwide due to divergent guidelines, uncertain mortality benefit, and variable patient selection. While WCDs are generally safe and can bridge patients during reversible risk periods, definitive survival benefit is unproven. Ongoing debates about appropriate patient selection and cost-effectiveness underscore the need for further trials and unified guidance. In the meantime, health policy should encourage prudent, case-by-case use of WCDs focused on those most likely to benefit.