A wearable cardioverter defibrillator successfully terminated tachyarrhythmias in 75% (6 of 8) of attempts, with inappropriate shocks occurring at a rate of 0.67% per month of use.
Observational (n=289)
Does a wearable cardioverter defibrillator successfully terminate tachyarrhythmias in patients at high risk for sudden death who are not candidates for an implantable device?
A wearable cardioverter defibrillator can successfully detect and terminate ventricular tachyarrhythmias in high-risk patients who are not immediate candidates for an ICD, serving as a potential bridge to permanent therapy.
The automatic ICD improves survival in patients with a history of sudden cardiac arrest. However, some patients do not meet the guidelines for ICD implantation or are unable to receive an implantable device. This study tested the hypothesis that these patients could benefit from a wearable cardioverter defibrillator. Patients with symptomatic heart failure and an ejection fraction of <0.30 (WEARIT Study) or patients having complications associated with high risk for sudden death after a myocardial infarction or bypass surgery not receiving an ICD for up to 4 months (BIROAD Study) were enrolled into two studies. After a total of 289 patients had been enrolled in the trial (177 in WEARIT and 112 in BIROAD), prespecified safety and effectiveness guidelines had been met. Six (75%) of eight defibrillation attempts were successful. Six inappropriate shock episodes occurred during 901 months of patient use (0.67% unnecessary shocks per month of use). Twelve deaths occurred during the study 6 sudden deaths: 5 not wearing and 1 incorrectly wearing the device). Most patients tolerated the device although 68 patients quit due to comfort issues or adverse reactions. The results of the present study suggest that a wearable defibrillator is beneficial in detecting and effectively treating ventricular tachyarrhythmias in patients at high risk for sudden death who are not clear candidates for an ICD and may be useful as a bridge to transplantation or ICD in some patients.
Feldman et al. (2004) conducted an observational in High risk for sudden death (n=289). Wearable cardioverter defibrillator was evaluated on Successful defibrillation attempts. A wearable cardioverter defibrillator successfully terminated tachyarrhythmias in 75% (6 of 8) of attempts, with inappropriate shocks occurring at a rate of 0.67% per month of use.