Introduction: Implantable cardioverter-defibrillator (ICD) and combination with cardiac resynchronization (CRT-D) therapy have become essential for management of patients with heart failure and impaired ejection fraction (EF). Both in primary and secondary prevention, these devices reduce the incidence of arrhythmic and all-cause death. Longer life expectancy has led to an increased rate of ICD implantation in patients over 75 years, but there are only few evidences on the survival benefit in this specific population.
Aim: To asses one year survival rate in patients who underwent ICD or CRT-D implantation above the age of 75, and to identify the presence of possible outcome predictors.
Methods: We retrospectively analyzed all clinical and survival data of 127 patients over 75 years who received an ICD or CRT-D for primary and secondary prevention in our laboratory from the year 2000 to 2013. Rates of appropriate device therapy were collected. Kaplan-Meier survival analysis was performed, and mortality predictors were identified.
Results: The median age of our patients was of 78 (76.0-80.0) years, 77% (98/127) were male, with a median EF of 30% (25-35%). ICD was implanted for primary prevention in 61% (78/127), and 20% (26/127) received a CRT-D. The median follow up was of 38.0 (22.0-62) months. The survival rate at one year was of 87.4% (111/127). Searching for one-year survival predictors, we found a significant correlation with decreased EF (p=0.026). In particular, patients with an EF?25%, had a higher mortality rate in comparison to patients with an EF >25% (50% vs 21.6%, p=0.015), with a significant survival difference (p Log-Rank=0.015). In the unvaried analysis no correlation was found with age, atrial fibrillation (AF), left bundle branch block, co-morbidities as diabetes and kind of implanted device. Instead significant correlation was found with impaired renal function (p=0.006) with a significant survival difference (p Log-Rank=0.004). In the multivariate analysis reduced EF was confirmed to be valid predictor of one-year mortality (p=0.015). The best model resulting from binary regression analysis showed EF ?25% and impaired renal function as risk factors for one-year mortality (p=0.002, p Hosmer=0.99) with a significant survival difference (p Log-Rank<0.001).
Conclusions: EF?25% and impaired renal function resulted as a marker of higher risk of one year mortality for elderly patients who underwent ICD or CRT-D implantation.