Clinical Predictors of Recurrent Ventricular Arrhythmias in Secondary Prevention Implantable Cardioverter Defibrillator Recipients With Coronary Artery Disease　― Lower Left Ventricular Ejection Fraction and Incomplete Revascularization ―

BACKGROUND: The implantable cardioverter defibrillator (ICD) is a standard prevention therapy for patients at high risk for sudden cardiac death (SCD) due to life-threatening ventricular arrhythmia (VA), that is, ventricular fibrillation and ventricular tachycardia. However, clinical predictors of recurrent VA in secondary prevention ICD recipients with coronary artery disease (CAD) remain unknown. METHODS AND RESULTS: We followed up 96 consecutive patients with CAD undergoing ICD implantation for secondary prevention of SCD. Long-term rates and clinical predictors of appropriate ICD therapy (ICD-Tx) for VA were analyzed. Appropriate ICD-Tx occurred in 41 (42.7%) patients during a median follow-up of 2.4 years (interquartile range, 0.9-6.1). These patients had significantly greater left ventricular end-diastolic diameter (62.3±1.3 vs. 54.6±1.1 mm, P<0.001), lower left ventricular ejection fraction (LVEF; 36.3±2.0% vs. 45.7±1.8%, P<0.001), and more incomplete revascularization (ICR; 70.7% vs. 45.5%, P=0.014) than those without appropriate ICD-Tx. Multivariable analysis showed that LVEF (hazards ratio [HR], 0.950; 95% CI: 0.925-0.975; P<0.001) and ICR (HR, 2.293; 95% CI: 1.133-4.637; P=0.021) were significant predictors of appropriate ICD-Tx for VA. CONCLUSIONS: Lower LVEF and ICR were independent predictors of recurrent VA in secondary prevention ICD recipients with CAD.