Wearing Protection or Wearing Assumptions? A Critical Reappraisal of the Wearable Cardioverter-Defibrillator

The wearable cardioverter-defibrillator (WCD) has become an accepted temporary strategy for patients considered at transient risk of sudden cardiac death and its use has rapidly expanded across a broad range of clinical settings. However, more than twenty years after its introduction, the evidence supporting its routine use remains surprisingly limited. This review revisits the background rationale, randomized evidence and observational literature. Rather than questioning the technical ability of the WCD to terminate ventricular arrhythmias, we critically examine whether available evidence demonstrates a meaningful improvement in prognosis. We discuss the lessons learned from early post-myocardial infarction Implantable Cardioverter Defibrillator (ICD) trials, the limitations of using appropriate shocks as surrogate endpoints, the interpretation of the VEST trial, the strengths and weaknesses of registry-based evidence, patient adherence and quality-of-life issues, the economic implications of WCD therapy, and the need for a more selective, evidence-based use of the WCD that identifies patients most likely to derive meaningful clinical benefit while promoting responsible stewardship of healthcare resources.