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.
Keywords: Atrial fibrillation; Decompensated heart failure; Heart failure; Stroke.