Incidence and Risk Factors of Stroke or Systemic Embolism in Patients With Atrial Fibrillation and Heart Failure　― The Fushimi AF Registry ―

BACKGROUND: Heart failure (HF) is a heterogeneous syndrome, but the effect of the type and severity of HF on the incidence of stroke or systemic embolism (SE) in atrial fibrillation (AF) patients is unclear. METHODS AND RESULTS: The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto, Japan. Follow-up data were available for 3,749 patients. We defined pre-existing HF as having one of the following: prior hospitalization for HF, presence of HF symptoms (NYHA ≥2), or reduced ejection fraction (<40%). At baseline, 1,008 (26.9%) patients had pre-existing HF. On multivariate analysis, the incidence of stroke/SE was not associated with pre-existing HF (hazard ratio (HR), 1.24; 95% confidence interval (CI), 0.92-1.64) or each criterion for the definition of pre-existing HF, but was associated with high B-type natriuretic peptide (BNP) or N-terminal proBNP levels (above the median of the pre-existing HF group) at baseline (HR, 1.65; 95% CI, 1.06-2.53). Stroke/SE was markedly increased in the initial 30-day period following hospital admission for HF (HR, 12.0; 95% CI, 4.59-31.98). CONCLUSIONS: The effect of HF on the incidence of stroke/SE may depend on the stage or severity of HF in patients with AF. The incidence of stroke/SE was markedly increased in the 30 days after admission for HF, but compensated 'stable' HF did not appear to confer an independent risk.