Prevalence of Subclinical Atrial Fibrillation in Heart Failure With Preserved Ejection Fraction

Background: Atrial fibrillation (AF) is common in patients with heart failure with preserved ejection fraction (HFpEF) and is associated with poorer clinical outcomes. The prevalence of subclinical AF in patients with HFpEF remains unknown. Objectives: The aim of this study was to determine whether subclinical AF was more prevalent in individuals with HFpEF than in individuals without histories of heart failure (HF). Methods: Patients with HFpEF with no prior diagnoses of AF were screened for subclinical AF, and the prevalence of subclinical AF was compared with that among control subjects without HF drawn from MESA (Multi-Ethnic Study of Atherosclerosis) who underwent the same electrocardiographic monitoring. Multivariable logistic regression was used to adjust for demographic and clinical comorbidities. Results: Ninety patients with HFpEF and 1,230 MESA participants were included. Patients with HFpEF were younger (median age 69 years [Q1-Q3: 63-76 years] vs 72 years [Q1-Q3: 66-80 years]; P = 0.02), more obese (median body mass index 36 kg/m² [Q1-Q3: 30-45 kg/m²] vs 27 kg/m² [Q1-Q3: 24-30 kg/m²]; P < 0.001), and more likely to have diabetes (34% vs 21%; P = 0.01). The prevalence of subclinical AF was 8.9% in patients with HFpEF and 4.1% in non-HF participants. After multivariable adjustment for age, sex, race, body mass index, diabetes, smoking, and total analyzable time on electrocardiographic monitor, there was a significantly higher odds of subclinical AF in patients with HFpEF compared with MESA (OR: 3.01; 95% CI: 1.13-7.99; P = 0.03). Conclusions: Patients with HFpEF had a higher prevalence of subclinical AF than participants without HF from a community-based study. Screening for atrial arrhythmias may be appropriate among patients with HFpEF for timely initiation of thromboembolic prophylaxis and may identify individuals at greater risk for clinical decompensation.