ESC Congress 2026 Abstract · Oct 26, 2026
Independent prognostic value of coronary artery calcification for ischemic stroke in patients with atrial fibrillation
By Lee KH, Kim CH, Lee YH
Background: Patients with atrial fibrillation (AF) are at substantially higher risk of ischemic stroke and systemic thromboembolism. Although the CHA2DS2-VASc score is commonly used to estimate stroke risk, it does not directly quantify atherosclerotic burden. Coronary artery calcium score (CACS) detects coronary atherosclerosis that may not be reflected in conventional clinical risk scores. Purpose: The study aims to evaluate the independent prognostic value of CACS for ischemic stroke in AF patients. Methods: We identified 14,965 patients who underwent cardiac computed tomography between 2006 and 2025. From this cohort, a total of 1,347 patients with AF and without a history of prior coronary intervention were analyzed. The primary endpoint was the 3-year incidence of ischemic stroke, stratified by CACS quantified using the Agatston method: minimal (0-9), mild (10-99), moderate (100-399), and severe (≥ 400). To mitigate confounding, inverse probability weighting was applied. Results: Adjusted hazard ratios (HRs) for the ischemic stroke according to CACS were mild 1.14 (95% CI 0.82-1.57; p = 0.435); moderate 1.99 (95% CI 1.49-2.65; p < 0.001); severe 1.51 (95% CI 1.11-2.05; p = 0.008). The stroke incidence curves grouped by two clusters: minimal-mild (log-rank p = 1.000), moderate-severe (log-rank p = 1.000), exhibiting a significant divergence between mild and moderate (log-rank p = 0.048). Even in the subgroup with non-significant coronary stenosis (<50%), moderate-severe CACS (≥ 100) remained significantly associated with ischemic stroke (HR 2.10, 95% CI 1.45-3.03; p < 0.001). In total cohort, moderate-severe CACS (HR 1.62, 95% CI 1.03-2.54, p = 0.037) demonstrated a risk magnitude comparable to the CHA2DS2-VASc age 65-74 component (HR 1.59, 95% CI 1.19-2.12; p = 0.002) (Wald p = 0.818). Incorporating CACS into the vascular component of the CHA2DS2-VASc score yielded a trend toward improvement in discrimination (ΔAUC +0.0121, 95% CI -0.0004 to +0.0246; p = 0.057). Conclusion: Above the moderate CACS (≥ 100) was an independent risk factor for 3-year ischemic stroke in patients with AF, which magnitude was comparable to the age 65-74 component of the CHA2DS2-VASc score. These findings suggest that CACS assessment may provide complementary stroke risk stratification in AF patients; however, further validation is required.calcium score