Implantable Cardioverter-Defibrillator Therapies Following Generator Replacements-Long-Term Remote Monitoring Data

Area of Science:

• Cardiology
• Electrophysiology
• Medical Device Technology

Background:

• Long-term outcomes following implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy-defibrillator (CRT-D) replacements are not well-established.
• Understanding arrhythmic episodes and mortality risk in remotely monitored patients after device replacement is essential for clinical management.

Purpose of the Study:

• To evaluate the risk of ICD or CRT-D therapies in remotely monitored patients undergoing device replacement.
• To identify predictors of all-cause mortality and appropriate/inappropriate device therapies post-replacement.

Main Methods:

• Analysis of data from 134 patients who underwent ICD/CRT-D replacement or upgrade.
• Utilized Kaplan-Meier estimates and Cox proportional hazards regression for outcome analysis.
• Endpoints included all-cause mortality, and appropriate and inappropriate ICD/CRT-D therapies.

Main Results:

• The cohort comprised 51.5% ICD and 48.5% CRT-D recipients, with a median LVEF of 23.0% at replacement.
• During a median follow-up of 3.0 years, 32.1% experienced appropriate and 6.0% experienced inappropriate therapies.
• All-cause mortality was 38.0%; predictors of death included appropriate antitachycardia pacing (ATP), reduced LVEF, and no history of myocardial infarction.

Conclusions:

• Improvement in left ventricular ejection fraction (LVEF) was not a predictor of improved survival or reduced device therapies after ICD/CRT-D replacement.
• An LVEF >35% at replacement did not influence analyzed outcomes.
• Further stratification models are needed to better evaluate arrhythmic risk in patients post-generator replacement.