Effectiveness, efficacy, and safety of wearable cardioverter-defibrillators in the treatment of sudden cardiac arrest – Results from a health technology assessment

Abstract

Objectives To assess the effectiveness, efficacy, and safety of a wearable cardioverter-defibrillator (WCD) in adult persons with high risk for sudden cardiac arrest and for which an implantable cardioverter is currently not applicable. Methods We performed a systematic literature search in Medline, Embase, Cochrane Library, and CRD-databases. Study selection was performed by two reviewers independently. Data were presented quantitatively; due to heterogeneity of studies no meta-analysis was performed. Results One randomized-controlled trial (RCT), one non-randomized comparative trial, and forty-four non-comparative trials were included. The RCT reported an overall mortality of 3.1 percent in the WCD group versus 4.9 percent in controls (relative risk [RR]: .64; 95 percent confidence interval [CI], .43–.98, p = .04), but no significant effect on arrhythmia-related mortality. The RR for arrhythmia-related mortality amounted to .67 (95 percent CI, .37–1.21, p = .18) as assessed in the RCT. Appropriate shocks were observed in 1.3 percent of patients in both comparative studies, and inappropriate shocks in .6 percent of patients in the RCT. Termination of ventricular tachycardia (VT) or ventricular fibrillation (VF) was successful in 75 to 100 percent of appropriate shocks in all studies. Adverse events assessed in the RCT showed a lower incidence of shortness of breath (38.8 percent vs. 45.3 percent; p = .004), higher incidence of rash at any location (15.3 percent vs. 7.1 percent; p < .001), and higher incidence of itching at any location (17.2 percent vs. 6.4 percent; p < .001) for WCD. Conclusions Available evidence demonstrates that the WCD detects and terminates VT/VF events reliably and shows a high rate of appropriate shocks in mixed patient populations. Data of large registries confirm that the WCD is a safe intervention.

Critical appraisal of “Goetz G, Wernly B, Wild C (2023) Wearable cardioverter defibrillator for preventing sudden cardiac death in patients at risk: An updated systematic review of comparative effectiveness and safety. IJC Heart & Vasculature 45 (2023) 101189”. Comment to the authors reply

“…The consequences of their judgement are as follows. Low compliance leads to lower effectiveness, therefore, we can expect an even greater effect associated to higher compliance, as indeed seen in real life studies as well as in the as-treated and per-protocol analyses of the RCT [7] , [8] , [9] . In terms of the adjudication committee, once a study participant has passed away, the focus of the adjudication committee is on the cause of death as the death itself is not in question.…”

“…Wild et al once more discredit a fellow researcher, by saying, it is reasonable to believe that Aidelsburger et al [8] counted publications instead of studies, because Masri et al included less publications [12] . From a factual perspective, both publications had a different scope and covered a different time period.…”

Patient-reported outcomes using a wearable cardioverter-defibrillator: results from a systematic review

“…In our previously published health technology assessment, we stated that QoL during WCD usage has not been investigated sufficiently (7). Since then, further study results concerning PRO have been published that justify the conduction of this systematic review.…”

“…We assessed PRO that can be defined as "an outcome reported directly by patients themselves and not interpreted by an observer; PRO may include patient assessments of health status, quality of life, satisfaction with care or symptoms, or patient-reported adherence to medication" (8). Clinical symptoms as a manifestation of health status and adherence to WCD usage have been published earlier (7). Therefore, in this systematic review we focus on QoL, utilities, and patient satisfaction during WCD usage.…”

“…In a previously published HTA we examined the effectiveness, efficacy, and safety of WCDs in the treatment of sudden cardiac arrest (7). At that time the effects of WCD usage on some patient-reported outcomes (PRO) like health-related quality of life (QoL), utilities, or patient satisfaction had not been investigated sufficiently.…”