Abstract 15734: Intersection of Atrial Fibrillation and Heart Failure With Mildly Reduced and Preserved Ejection Fraction in >400,000 Participants in the Get With the Guidelines® Heart Failure Registry

Abstract

Introduction: Atrial fibrillation or flutter (AF) and heart failure (HF) frequently coexist, yet few studies have examined longitudinal trends or post-discharge outcomes in this disease intersection. Methods: We evaluated 429,464 participants hospitalized for HF and left ventricular ejection fraction >40% across 644 sites in the Get With The Guidelines-Heart Failure (GWTG-HF) registry from January 2014 to December 2020. We compared clinical profiles among those with and without AF (defined by medical history or occurring at presentation or during hospitalization). We additionally examined 12-month post-discharge death and all-cause/cause-specific readmissions among 79,895 participants ≥65 years discharged alive with linked Centers for Medicare & Medicaid Services inpatient files and Parts A, B, and D Fee-for-Service eligibility. Results: Prevalence of AF increased from 48.5% in Q1 2014 to 52.1% in Q4 2020 among the 76,886 patients with HF with mildly reduced ejection fraction (HFmrEF; 41-49%) and increased from 49.7% to 50.1% among the 352,578 patients with HF with preserved ejection fraction (HFpEF; ≥50%); both P-trend<0.001. Among those with AF, 28% had a history of AF but were not actively in AF during hospitalization, while 11% had newly-detected AF at time of hospitalization. Median heart rate among those with AF was 80 (69-95)bpm at admission and 75 (66-86)bpm at discharge. Patients with AF faced higher 12-month rates of death (35% vs. 29%) and readmission for HF (30% vs. 27%), stroke (2.1% vs. 1.7%), bleeding (6% vs. 5%), and AF (5% vs. 2%). These associations persisted after adjustment for sociodemographic and clinical risk factors ( Figure ). Conclusions: Prevalence of AF is rising among patients hospitalized with HFmrEF and HFpEF. AF is independently associated with increased post-discharge risks of death and a broad range of clinical events requiring rehospitalization.