Tachycardia Therapy Outcomes of Ischemic Versus Nonischemic Cardiomyopathy on Cardiac Resynchronization Therapy: A...

Area of Science:

• Cardiology
• Electrophysiology
• Heart Failure Management

Background:

• Cardiac resynchronization therapy with defibrillator (CRT-D) is a key treatment for heart failure.
• Dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM) represent distinct etiologies of heart failure with potentially different responses to CRT-D.

Purpose of the Study:

• To compare tachycardia therapy outcomes and mortality in patients with DCM versus ICM treated with CRT-D.
• To identify predictors of appropriate therapy and mortality in this patient population.

Main Methods:

• Retrospective analysis of 78 patients (42 DCM, 36 ICM) implanted or upgraded to CRT-D.
• Evaluation of non-sustained ventricular tachycardia (NSVT), non-sustained ventricular fibrillation (NSVF), defibrillator therapies, anti-tachycardia pacing (ATP), and mortality.
• Statistical analysis including survival analysis and Cox proportional hazards models.

Main Results:

• Time to first therapy was numerically longer in DCM patients (9.5 ± 2.4 vs. 7.1 ± 3.2 months).
• DCM patients showed significantly higher therapy-free survival (P=0.017) and lower mortality (P=0.029) compared to ICM.
• Independent predictors of appropriate therapy included ICM, coronary artery disease (CAD), and NSVT. Predictors of mortality included CKD and CAD.

Conclusions:

• The clinical course of ICM and DCM patients treated with CRT-D differs significantly.
• ICM patients experience increased tachycardia therapy and mortality compared to DCM patients during follow-up.