Use of the wearable cardioverter defibrillator in high-risk cardiac patients: data from the Prospective Registry of Patients Using the Wearable Cardioverter Defibrillator (WEARIT-II Registry)

Circulation. 2015 Oct 27;132(17):1613-9. doi: 10.1161/CIRCULATIONAHA.115.015677. Epub 2015 Aug 27.

Abstract

Background: Prospective data on the safety and efficacy of the wearable cardioverter defibrillator (WCD) in a real-world setting are lacking. The Prospective Registry of Patients Using the Wearable Defibrillator (WEARIT-II) Registry was designed to provide real-world data on the WCD as a strategy during a period of risk stratification.

Methods and results: The WEARIT-II Registry enrolled 2000 patients with ischemic (n=805, 40%), or nonischemic cardiomyopathy (n=927, 46%), or congenital/inherited heart disease (n=268) prescribed WCD between August 2011 and February 2014. Clinical data, arrhythmia events, implantable cardioverter defibrillator implantation, and improvement in ejection fraction were captured. The median age was 62 years; the median ejection fraction was 25%. The median WCD wear time was 90 days, with median daily use of 22.5 hours. There was a total of 120 sustained ventricular tachyarrhythmias in 41 patients, of whom 54% received appropriate WCD shock. Only 10 patients (0.5%) received inappropriate WCD therapy. The rate of sustained ventricular tachyarrhythmias by 3 months was 3% among patients with ischemic cardiomyopathy and congenital/inherited heart disease, and 1% among nonischemic patients (P=0.02). At the end of WCD use, 840 patients (42%) were implanted with an implantable cardioverter defibrillator. The most frequent reason not to implant an implantable cardioverter defibrillator following WCD use was improvement in ejection fraction.

Conclusions: The WEARIT-II Registry demonstrates a high rate of sustained ventricular tachyarrhythmias at 3 months in at-risk patients who are not eligible for an implantable cardioverter defibrillator, and suggests that the WCD can be safely used to protect patients during this period of risk assessment.

Keywords: death, sudden, cardiac; defibrillator, implantable; defibrillators; tachycardia, ventricular.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Arrhythmias, Cardiac / drug therapy
  • Arrhythmias, Cardiac / etiology
  • Arrhythmias, Cardiac / prevention & control*
  • Arrhythmias, Cardiac / therapy
  • Cardiomyopathies / complications
  • Cardiovascular Agents / therapeutic use
  • Combined Modality Therapy
  • Death, Sudden, Cardiac / prevention & control
  • Defibrillators* / adverse effects
  • Defibrillators* / statistics & numerical data
  • Defibrillators, Implantable / statistics & numerical data
  • Electric Countershock / instrumentation*
  • Female
  • Follow-Up Studies
  • Heart Defects, Congenital / complications
  • Humans
  • Male
  • Middle Aged
  • Myocardial Ischemia / complications
  • Patient Compliance
  • Prescriptions / statistics & numerical data
  • Prospective Studies
  • Registries
  • Stroke Volume

Substances

  • Cardiovascular Agents