Experience With Wearable Cardioverter-Defibrillators at 2 Academic Medical Centers

Abstract

Objectives: This study sought to characterize the experience in a cohort of patients prescribed a wearable cardioverter-defibrillator (WCD) over a 2-year interval at 2 academic medical centers.

Background: The WCD is available for patients felt to be at high risk of sudden cardiac death. However, there is a lack of randomized data to guide its use and prescribing patterns vary.

Methods: We retrospectively reviewed indications and therapies of all WCD prescriptions over a 2-year period from 2 large academic medical centers. Data on compliance and treatment events of patients wearing the WCD were reviewed.

Results: Among the 147 patients prescribed a WCD, 80% were male with an age of 59 ± 14 years. The WCD was prescribed for the following reasons: primary prevention in the setting of a left ventricular ejection fraction ≤35% (53%), secondary prevention when an implantable cardioverter-defibrillator was not implanted (16%), implantable cardioverter-defibrillator explantation (23%), and other high-risk scenarios for arrhythmic sudden death (9%). The median wear duration was 50 days (interquartile range [IQR]: 25 to 85 days) with a median of 21.0 h of wear per day (IQR: 15.0 to 22.8 h). High-voltage treatment was delivered in 3 separate patients, 2 of whom died. The third patient received 3 WCD shocks without restoration of a perfusing rhythm and ultimately was resuscitated by emergency responders. No patients received inappropriate therapies.

Conclusions: Events requiring therapy were rare and no lives were directly saved by the WCD. Future efforts are needed to improve identification of patients most likely to benefit from a WCD.

Keywords: arrhythmias; cardiomyopathy; sudden cardiac death.