PO06-21: Benefit of implantable cardioverter defibrillator in patients with improved left ventricular systolic function

Introduction: About 25% patients with primary prevention implantable cardioverter-defibrillator (ICD) will have improved left ventricular (LV) ejection fraction (EF) on follow-up. Whether ICD benefits this cohort is largely unknown. Methods: Clinical characteristics and outcomes of patients in the Aurora Health System with transient LV dysfunction (initial LVEF≤35% that improved to ≥40%, during 1/1/2010-12/31/2014, were compared between primary prevention ICD recipients and those without ICD. Patients with cardiac resynchronization therapy, cardiac transplant and LV assist devices were excluded. We used Kaplan-Meier, chi-square and Fisher exact test for analysis. Results:One thousand three hundred sixty-four patients developed transient LV dysfunction. One hundred forty-eight (10.8%) had ICD implant. ICD recipients (vs. non-ICD patients) were more likely to be male (72% vs. 28.4%, p Conclusions: ICD is associated with mortality benefit in patients with transient LV dysfunction suggesting continued sudden death protection in patients with LVEF≥40%. This highlights the drawbacks of LVEF as ICD implant criterion