Sex-Specific Coronary Artery Calcium Score Threshold Predictive of Obstructive Coronary Artery Disease

Coronary computed tomography angiography and coronary artery calcium score (CACS) are rapidly being adopted for the noninvasive assessment of coronary artery disease (CAD). One of the primary limitations of calcium imaging is the inability to assess obstructive lesions in the presence of a high calcium burden. Currently, there is no guidance on what level of coronary artery calcium indicates a high risk of obstructive CAD. We aimed to determine sex-specific CACS thresholds suggestive of obstructive CAD by comparing coronary angiography with adjunctive tools to available CACS information. From August 2018 to August 2023, we retrospectively analyzed 1799 consecutive patients' clinical characteristics, angiographic information, and available intracoronary physiological/anatomical testing at a single institution. We evaluated the sex-specific distribution of CACS and its specificity for identifying obstructive CAD at a threshold of 90%. Baseline characteristics were similar between the obstructive (n = 1223) and nonobstructive (n = 576) CAD groups. A CACS of ≥1000 in women (HR, 2.81; 95% CI, 1.77-4.47; P < .001) and ≥1400 in men (HR, 3.34; 95% CI, 2.23-5.02; P < .001) predicted obstructive CAD at 90% specificity. A CACS of ≥1000 in women and ≥1400 in men identifies obstructive CAD at 90% specificity. These thresholds should be prospectively validated and may potentially be used to guide the selection of patients who would benefit from intensification of medical therapy or invasive evaluation in the appropriate clinical context.