C-44 | Identifying the Coronary Artery Calcium Score Threshold Indicative of Obstructive Coronary Artery Disease

Coronary computed tomography angiography can effectively risk stratify patients with low-to-intermediate risk for coronary artery disease (CAD). However, it is currently unknown at what level of coronary artery calcium score (CACS) there may be a high likelihood of obstructive CAD compared with coronary angiography. We retrospectively analyzed 1799 consecutive patients who presented to our center where CACS was available from 8/2018 to 8/2023 as part of their previous evaluation. We aimed to establish a CACS threshold for obstructive CAD and performed specificity analysis at 90%, based on the final angiographic assessment. Adjunctive intravascular physiological assessment/imaging was employed when necessary for intermediate lesions, following the 2021 ACC/AHA/SCAI Guidelines for Coronary Artery Revascularization. The final angiographic assessment was classified into obstructive or non-obstructive CAD. Among the analyzed patients, 1169 were male, and 630 were female. Baseline clinical characteristics were comparable overall, although hyperlipidemia, diabetes, and family history of CAD were more prevalent in patients with obstructive CAD. Non-obstructive disease and atrial fibrillation were more common in female patients. Figures 1 and 2 illustrate the sex-specific distribution of CACS. Compared with coronary angiography and adjunctive tools for intermediate lesions, a CACS of ≥1400 in males and ≥1000 in females established sex-specific thresholds for obstructive CAD with 90% specificity.