Impact of Atrial Fibrillation in Heart Failure With Normal Ejection Fraction: A Clinical and Echocardiographic Study

Abstract

Background The clinical significance of atrial fibrillation (AF) in heart failure with normal ejection fraction (HFNEF) remains undetermined. Methods and Results We compared the clinical and echocardiographic characteristics among 238 patients hospitalized for HF. Using the cutoff of left ventricular EF of 50%, there were 146 patients with HFNEF (AF = 42) and 92 with systolic HF (AF = 30). When compared among HFNEF, the New York Heart Association (NYHA) class (2.61 ± 0.51 versus 2.21 ± 0.46; P < .05), 6-minute walk distance (279.7 ± 66.0 versus 338.0 ± 86.1 m; P < .01), quality of life score (26.1 ± 14.3 versus 19.5 ± 10.3; P < .05), and previous HF hospitalization were significantly worse in the AF group. These variables were significantly better in HFNEF than systolic HF with sinus rhythm, but the differences were not detected among those with AF. Patients with HFNEF and AF were associated with more severe diastolic dysfunction when compared to sinus rhythm. With a median follow-up of 10.5 months, the proportion of HFNEF patients in AF with recurrent HF hospitalization or death was significantly higher than those in sinus rhythm (28.6% versus 10.6%; P < .01). Both AF and restrictive diastolic dysfunction were independent predictors of HF hospitalization or death in HFNEF. Conclusion Patients with HFNEF and AF were associated with more severe diastolic dysfunction and worse clinical outcomes than those in sinus rhythm.