Abstract 2666: Limited Contribution of Sudden Death Prevention to Survival after Repeated Heart Failure Hospitalizations
Context: Clinical trials demonstrate a survival benefit of implantable cardioverter-defibrillators (ICD) in patients with mild-moderate heart failure (HF). However, HF trials often exclude older patients with significant comorbidities. We assessed the potential contribution of sudden death prevention in patients with repeated HF hospitalizations.
Method: 14,374 patients with a first hospitalization for HF in British Columbia (2000 – 04) were tracked for subsequent HF hospitalizations, mortality, and cause of death. We coded all out of hospital (OOH) cardiac deaths as sudden cardiac deaths, assuming that all could be prevented by ICD. All OOH cardiac deaths were censored and the potential survival was analyzed by Kaplan-Meier survival analysis.
Results: The mean age was 77 years, 45% were women, 47% had coronary artery disease, 11% had cerebrovascular disease, 21% had chronic kidney disease, and 1% had ICD. 1,142 of 7,401 deaths (15%) were OOH deaths during 24,766 person-years of follow-up. Even if all OOH cardiac deaths could have been prevented, overall median survival declined rapidly after each subsequent HF hospitalization. [Figure⇓] Patients >=70 years had higher mortality, and half were dead within 1.5 yrs after the 2nd HF hospitalization. Many patients <70 years were still alive at 3 yrs even after the 3rd hospitalization, but most were dead within 1.5 yrs after the 4th hospitalization. Conclusions: Even if all OOH cardiac death could be prevented by ICD, survival declines rapidly after repeated HF hospitalizations. Indications for ICD therapy should be critically reviewed for older patients with >= 2 hospitalizations and younger patients with >= 4 hospitalizations.