Association between atherosclerosis and atrial fibrillation progression in patients with paroxysmal atrial fibrillation: Data from the RACE V study

• Atherosclerosis was present in two-thirds of patients with paroxysmal AF, mostly subclinical. • Patients with atherosclerosis had an increased risk of AF progression. • Atherosclerosis remained a determinant of AF progression after adjustment for risk factors. • Findings suggest vascular disease may contribute to atrial remodeling and arrhythmia persistence. Atrial fibrillation (AF) may progress from paroxysmal AF (PAF) to more persistent forms, but the underlaying mechanisms are not well understood. The aim of this study was to assess the association between atherosclerosis and AF progression in patients with PAF. In this substudy of RACE V, 612 patients with PAF underwent extensive phenotyping at baseline and continuous rhythm monitoring. The association between atherosclerosis and AF progression was investigated. The median age was 64 (57–70) years, 257 (42%) were women, and the median CHA 2 DS 2 -VA score was 2 (1–3). At baseline, 395 (65%) patients had atherosclerosis, defined by carotid/coronary imaging and/or history of vascular disease. Patients with atherosclerosis were older, had higher waist circumference, more hypertension, and lower eGFR than patients with no atherosclerosis. During a median of 3.4 (2.8–3.7) years follow-up, 108 (18%) patients had AF progression. The presence of atherosclerosis was associated with increased progression (21% vs. 12%; p = 0.004). In univariable analyses, atherosclerosis was a determinant of AF progression (OR: 2.04; 95% CI: 1.28–3.37; p = 0.004), and the association persisted following adjustment for established risk factors (OR: 2.23; 95% CI: 1.10–4.89; p = 0.034). In patients with paroxysmal AF, 65% of patients had atherosclerosis. Atherosclerosis was a determinant of AF progression after adjustment for established risk factors and comorbidities, suggesting that vascular disease may contribute directly to atrial remodelling and arrhythmia persistence.