Predictors of appropriate interventions and mortality in patients with implantable cardioverter-defibrillators

INTRODUCTION Additional risk assessment in patients with heart failure referred for implantable cardioverter-defibrillator (ICD) implantation as primary prevention is needed. A reduction in left ventricular ejection fraction (LVEF) seems to lack sufficient sensitivity and specificity to be used for identification of patients at the highest risk of sudden cardiac death. OBJECTIVES The aim of this study was to identify short- and long-term predictors of appropriate implantable cardioverter-defibrillator therapy as well as predictors of long-term mortality in patients with an ICD or cardiac resynchronization therapy defibrillator (CRT-D). PATIENTS AND METHODS In this retrospective study, data from 457 patients who had an ICD or CRT-D implanted between 2011 and 2017 were analyzed. RESULTS During the median follow-up of 31 months (interquartile range, 17-52 months), 153 patients died (33.9%) and 140 had appropriate interventions (31%). In a multivariate Cox regression analysis, implantation for secondary prevention (hazard ratio [HR], 2.49; P <0.001), severe mitral valve disease (HR, 2.17; P <0.001), and previous myocardial infarction (HR, 1.68; P = 0.009) were predictors of appropriate intervention. Resynchronization therapy (HR, 0.59; P = 0.025) and severe mitral valve disease (HR, 2.42; P <0.001) were predictors of appropriate intervention in primary prevention. Body mass index, hemoglobin concentrations, LVEF, diabetes, and left atrial diameter were significant predictors of death. CONCLUSIONS Implantation of ICD or CRT-D as secondary prevention was a potent predictor of appropri- ate intervention, while resynchronization therapy and severe mitral regurgitation predicted ICD therapy in primary prevention. In patients with ICD or CRT-D, independent predictors of mortality included: body mass index, hemoglobin concentrations, LVEF, diabetes, and left atrial diameter.