Survival benefit of the implantable cardioverter-defibrillator in patientson the waiting list for cardiac transplantation

Background-The implantable cardioverter-defibrillator (ICD) effectively red uces sudden cardiac death in patients with severe LV dysfunction. Effect of ICD therapy on total mortality in patients on the waiting list for cardiac transplantation is still uncertain. Methods and Results-We retrospectively analyzed 854 unselected consecutive patients (ICD therapy, n = 102; 11.9%) on the waiting list for cardiac tran splantation between January 1992 and March 2000. Actuarial 12-month total m ortality rate on the waiting list was 24.2%; sudden cardiac death was the p redominant mode of death (66.7% of total deaths). Kaplan-Meier analysis rev ealed improved survival for ICD (total mortality, 13.2%) compared with non- ICD (total mortality, 25.8%) patients (log rank, P=0.03). No event of sudde n death occurred in ICD patients, whereas in non-ICD patients. 12-month sud den death rate was 20.1% (P=0.0001). Nonsudden death rates did not differ b etween ICD and non-ICD patients (P=0.16). A Cox proportional hazards model demonstrated that absence of an ICD was a powerful independent predictor of total mortality (P=0.02; relative risk, 2.22; 95% confidence interval, 1.1 6 to 4.17) and sudden cardiac death (P <0.0001; infinite relative risk) on the waiting list. Conclusions-ICD therapy, because it prevents sudden cardiac death, signific antly improves survival on the waiting list for cardiac transplantation. Th e present study supports the use of ICDs as a bridge to transplantation in patients who are at risk of sudden cardiac death. Prospective randomized tr ials are needed to evaluate the potential benefit of prophylactic ICD thera py as a bridge to transplantation in all patients on cardiac transplant wai ting lists.