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The following is a summary of “Periprocedural outcomes from the postmarket study of the extravascular implantable cardioverter-defibrillator: preliminary Enlighten study results and meta-analysis,” published in the April 2025 issue of Heart Rythm Society by Crozier et al.

The extravascular implantable cardioverter-defibrillator (EV-ICD) system has demonstrated promising safety and efficacy in controlled, premarket clinical trials, but its real-world performance remains largely uncharacterized. This study presents interim findings from the ongoing Enlighten (EV-ICD Post-Approval Registry) Study—a global, prospective, postmarket registry aimed at evaluating the periprocedural safety, procedural success, and initial electrical performance of the Aurora EV-ICD system (Medtronic, Mounds View, MN) in routine clinical practice. The registry includes patients with a guideline-based indication for ICD therapy who were scheduled to undergo implantation of the EV-ICD system. 

Key metrics assessed included procedural characteristics, success rates of tunneling and substernal lead placement, defibrillation testing outcomes, the incidence of system- or procedure-related major complications, and pacing therapy parameters at the time of discharge. In this analysis, data were collected from 228 patients undergoing attempted EV-ICD implantation, with a mean age of 49.4 ± 15.4 years, of whom 27.9% were female, and the average left ventricular ejection fraction was 43.5 ± 16.1%. The procedural success was notably high, with 227 out of 228 patients (99.6%) achieving successful substernal lead placement. Following intraoperative defibrillation testing, 221 patients (96.9%) remained implanted with the device and entered the follow-up phase. Among patients who underwent defibrillation testing, successful ventricular arrhythmia termination was achieved in 191 of 193 individuals (99.0%). 

Importantly, the incidence of major complications related to the device or procedure by the time of hospital discharge was limited to 3.9%, suggesting a favorable short-term safety profile. Additionally, the electrical parameters recorded at discharge indicated system stability and appropriate function. These findings align closely with results from earlier premarket trials, reinforcing the EV-ICD system’s reliability and procedural feasibility when applied in diverse, real-world clinical settings. Collectively, these data provide early postmarket evidence that the EV-ICD system is both safe and effective in delivering life-saving therapy for patients at risk of sudden cardiac death, with complication rates and arrhythmia termination success comparable to or better than conventional transvenous ICD systems. 

As the enlightened registry progresses, longer-term follow-up will further clarify the durability, clinical performance, and patient-centered outcomes associated with this novel extravascular technology in broader populations.

Source: heartrhythmjournal.com/article/S1547-5271(25)00127-4/abstract