Contemporary Implantable Cardioverter-Defibrillator Benefit: Time to First Therapy in a Large, Real-World Cohort

Area of Science:

• Cardiology
• Medical Devices
• Electrophysiology

Background:

• Implantable cardioverter-defibrillators (ICDs) are crucial for reducing mortality in patients at risk of sudden cardiac death.
• Advances in heart failure management may influence the utilization and effectiveness of ICD therapies.
• An updated assessment of ICD benefit in contemporary patient populations is warranted.

Purpose of the Study:

• To evaluate the time to first therapy in current ICD recipients.
• To estimate the proportion of appropriate ICD therapies using adjudicated data.
• To analyze therapy incidence based on primary versus secondary prevention indications.

Main Methods:

• Analysis of a de-identified database (Medtronic CareLink, 2013-2024) of 237,627 single- or dual-chamber ICD recipients.
• Generation of cumulative incidence curves for shock, antitachycardia pacing (ATP), and any therapy.
• Manual adjudication of 595 randomly selected episodes to assess therapy appropriateness, with results extrapolated to the entire cohort.

Main Results:

• The 10-year cumulative incidence of first appropriate shock, ATP, or any therapy was 33%, 42%, and 48%, respectively.
• Patients receiving ICDs for secondary prevention showed higher rates of appropriate therapy compared to primary prevention patients (e.g., 41% vs. 32% for first appropriate shock at 10 years).
• Male patients constituted 71.8% of the study population.

Conclusions:

• Approximately 48% of contemporary patients receive appropriate ICD therapy within 10 years of implantation.
• These findings underscore the continued clinical benefit of ICDs, even with advancements in cardiac care and device management.
• ICDs remain a vital tool in managing patients at risk for sudden cardiac death.