Choosing between coronary CT angiography and functional tests in patients with suspected coronary artery disease: mind the (gender) gap

Abstract Introduction There is a need for a simple method to choose between a functional vs. anatomical test as first line approach to patients with suspected coronary artery disease (CAD). While European Guidelines base the decision on pretest probability (PTP) without a clear threshold, American Guidelines rely uniquely on age, with a 65-year-old cut-off for both genders. The aims of this study were: 1) to assess the proportion of patients undergoing coronary CT angiography (CCTA) in whom a functional test could have been more suitable due to extensive coronary artery calcification (CAC) and/or inconclusive CCTA results; 2) compare PTP vs. age to predict the presence of these suboptimal conditions for CCTA. Methods Individuals 40-80 years old were identified in a single center registry of patients with stable chest pain or dyspnea who underwent CCTA. Patients with known CAD, severe valvular disease, or irregular heart rhythms were excluded. PTP of obstructive CAD was calculated using age, sex, and symptom typicality. Patients were considered to have suboptimal conditions for CCTA if extensive CAC was present (defined conservatively as an Agatston score >400) or if one or more segments >2mm were deemed non-evaluable despite CAC score ≤ 400. Results A total of 884 patients (57% women, mean age 62±10 years) were included. Symptoms consisted of chest pain in 705 patients (80%). The median PTP of obstructive CAD was 22% (IQR 14-32). Overall, 162 patients (18%) had suboptimal conditions for CCTA due to CAC score >400 (n=140), or ≥1 non-evaluable segments (n=22). The proportion of patients with suboptimal conditions for CCTA was significantly higher in men than in women (27% vs. 12%, respectively; p<0.001). For both genders, the discriminative power to predict suboptimal CCTA conditions was significantly higher for age than for PTP (c-statistic in men 0.74 vs. 0.64, p<0.001; in women 0.71 vs. 0.62, p=0.012). In every age group, the proportion of patients with suboptimal conditions for CCTA was at least 2 times higher in men than in women, with a 10-15 year gap between genders - Fig. Conclusion Suboptimal conditions for a fully diagnostic CCTA were found in 18% of patients, were more strongly associated with age than with PTP, and were at least 2 times more frequent in men than in women across all age groups. These findings support the use of an age cut-off for anatomical vs. functional testing in men, and the use of CCTA as first line test in most women regardless of age.Proportion of patients suboptimal CCTA