Residual risk of stroke and death in anticoagulated patients according to the type of atrial fibrillation: AMADEUS Trial

BACKGROUND AND PURPOSE: Atrial fibrillation (AF) and heart failure frequently coexist and are associated with increased morbidity and mortality. We investigated the prognosis of anticoagulated patients with permanent AF and nonpermanent AF according to preexisting heart failure in the AMADEUS (Evaluating the Use of SR34006 Compared to Warfarin or Acenocoumarol in Patients With Atrial Fibrillation) trial.

METHODS: The primary outcome was a composite of cardiovascular death and stroke or systemic embolism, analyzed using a Cox proportional hazards model, adjusted for baseline age, sex, diabetes mellitus, hypertension, creatinine, and previous cardiovascular diseases. The median follow-up was 11.6 months (interquartile range, 6.2-15.2).

RESULTS: Nonpermanent AF was present in 2072 patients (46% of cohort), of which 339 (16%) had preexisting heart failure. A total of 2484 patients had permanent AF (54% of cohort), with a higher burden of heart failure including 730 patients (29%; P<0.001). Overall, death because of cardiovascular causes occurred in 57 patients and 45 had stroke or systemic embolism (1.4/100 person-years for each). Overall, the adjusted incidence of the composite outcome was higher in patients with permanent AF than in patients with nonpermanent AF. In multivariate analysis, permanency of AF, creatinine, prior cerebrovascular events, and previous coronary disease were independently associated with the primary outcome. The hazard ratio for permanent versus nonpermanent AF was 1.68 (95% confidence interval, 1.08-2.55; P=0.02). The presence of heart failure increased the risk of adverse outcomes in a similar way in both permanent and nonpermanent AF (interaction P value=0.76).

CONCLUSIONS: The risk of cardiovascular death, stroke, or systemic embolism is higher in anticoagulated patients with permanent AF than in those with nonpermanent AF, regardless of preexisting heart failure.