Abstract
Background/Aims Atrial fibrillation (AF) and heart failure (HF) are two of the most common cardiovascular conditions nationally and AF frequently complicates HF. We examined how AF impacts adverse outcomes in HF with preserved left ventricular ejection fraction (HF-PEF) vs. reduced ejection fraction (HF-REF) within a large, contemporary cohort.
Methods We identified all adults diagnosed with HF-PEF or HF-REF based on hospital discharge and ambulatory visit diagnoses and relevant imaging results between 2005–2008 from four health plans in the Cardiovascular Research Network. Data on demographic features, diagnoses, procedures, outpatient pharmacy use, and laboratory results were ascertained from health plan databases. Hospitalizations for HF, stroke, and any other reason were identified from hospital discharge and billing claims databases. Deaths were ascertained from health plan and state death files.
Results Among 23,644 patients with HF, 11,429 (48.3%) had documented AF (9,081 pre-existing, 2,348 incident). Compared with patients who did not have AF, patients with AF had higher adjusted rates of ischemic stroke (hazard ratio [HR] 2.47 for incident AF; HR 1.57 for pre-existing AF), hospitalization for HF (HR 2.00 for incident AF; HR 1.22 for pre-existing AF), all-cause hospitalization (HR 1.45 for incident AF; HR 1.15 for pre-existing AF), and death (incident AF HR 1.67; pre-existing AF HR 1.13). The associations of AF with these outcomes were similar for HF-PEF and HF-REF, with the exception of ischemic stroke.
Conclusions AF is a potent risk factor for adverse outcomes in patients with HF-PEF or HF-REF. Effective interventions are needed to improve the prognosis of these high-risk patients.




