The IC-D score for predicting prophylactic cardioverter-defibrillator implantation following acute myocardial infarction.

Abstract

A reduced left ventricular ejection fraction (LVEF) ≤35% ≥6weeks following an acute myocardial infarction (MI) may indicate prophylactic implantation of a cardioverter-defibrillator (ICD). We sought to find predictors of absence of significant left ventricular (LV) remodeling post-MI. All consecutive patients hospitalized for acute MI with an LVEF ≤35% at discharge in our institution from 2010 were retrospectively included. Patients were assigned to two groups according to the persistence of an LVEF ≤35% (ICD+) or a recovery>35% (ICD-). Logistic regression was performed to build a predictive score, which was then externally validated. Among a total of 1533 consecutive MI patients, 150 met inclusion criteria, 53 (35%) in the ICD+ group and 97 in the ICD group. After multivariable analyses, an LVEF ≤25% at discharge (adjusted OR 6.23 [2.47 to 17.0], p<.0001) and a CPK peak at the MI acute phase>4600 UI/L (adjusted OR 9.99 [4.27 to 25.3], p<.0001) both independently predicted non-recovery at 6weeks. The IC-D (Increased Cpk-LV Dysfunction) score predicted persistent LVEF ≤35% with areas under curve of 0.83 and 0.73, in the study population and in a multicenter validation cohort of 150 patients, respectively (p<.0001). The association of a severely reduced LVEF and a major release of myocardial necrosis biomarkers at the acute phase of MI predict unfavorable remodeling, and prophylactic ICD implantation.