Abstract 17482: Association of Ankle-Brachial Index with Coronary Artery Calcium Scoring for Coronary Vascular Disease Risk Stratification

Abstract

Introduction: The Ankle-Brachial Index (ABI) and coronary artery calcium scoring (CACS) are important tools for cardiovascular disease risk stratification. This study aimed to investigate the association between ABI index in combination with CACS for risk stratification of coronary vascular disease. Hypothesis: Given that both the ABI and the Coronary Artery Calcium Scoring are predictors of cardiovascular events, we hypothesize that an association between the Multiethnic Study on Subclinical Atherosclerosis Coronary Artery Calcium Scoring (MESA-CACS) and ABI exists. Methods: A total of 2655 patients (mean age 59±6 years, 72% male, and 87% white) who underwent CACS screening and ABI as part of a primary prevention screening program at the Cleveland Clinic between March 2016 and October 2021 were included in this study. ABI measurements were obtained by dividing the ankle systolic blood pressure by the brachial systolic blood pressure. The 10-year risk score based on MESA-CACS was calculated and categorized into 4 groups (<1%, 1-4.99%, 5-9.99% and ≥10%). ABI was categorized into normal (1-1.4), non-compressible (≥ 1.4) and abnormal (< 1). Results: Among the total of 2655 patients, 164 (6%) had a MESA-CAC score of <1%, 1566 (59%) had a score of 1-4.99%, 501 (19%) had a score of 5-9.99%, and 424 (16%) had a score of ≥10%. The median ABI was 1.17 (range 0.79-1.77) on the left and 1.17 (0.50-1.78) on the right. Tabulating the patients based on their ABI index across the MESA-CACS categories showed no significant difference among the groups with a p-value of 0.830 (Fig 1), with the majority of the patients (> 98% of patients) in all 4 groups having a normal ABI index of 1-1.4. Conclusion: The ABI did not demonstrate a significant association with the MESA-CACS, suggesting its potential use as a synergistic marker for coronary vascular disease risk stratification. Long-term cohort studies are needed to validate this result.