Coronary artery calcium score above 250 confirms the presence of significant stenosis in coronary CT angiography of symptomatic patients

Objectives Evaluation of coronary artery calcium score (CACS) at multiple low and high cutoff values for the detection of significant coronary stenosis at two different cutoffs (50 and 70%) in a large number of symptomatic patients was not investigated previously in one study. This study aims to investigate if there are a correlation and statistical significance between different CACS cutoffs and the severity of coronary artery stenosis by coronary CT angiography (CCTA) in symptomatic patients. Methods This is a retrospective study that included all symptomatic patients who had CCTA in a tertiary care hospital over a period of 7 years. Results CCTA of 502 patients was evaluated (406 included, mean age 56.2 years); 230 were males (56.7%). The prevalence of stenosis at any percentage was 53.7%, ≥50% was 26.6% and ≥70% was 12.3%. The mean CACS was 84.5 (range 0–1860), for males was 124.5 and for females was 32.1. Patients with CACS of zero (59%) and CACS of ≥1 (41%) had a mean stenosis of 8.9% (range 0–75%) and 52.6% (range 0–100%), respectively. All patients with a CACS of ≥250 were found to have ≥50% stenosis (100% specificity and positive predictive value, 35.2% sensitivity, 81% negative predictive value and 82.6% accuracy). The percentage of stenosis increased as CACS increased with strong statistical significance ( P value < 0.0001) and a positive correlation ( r = 0.58). Conclusions CACS is a valuable diagnostic tool to predict the severity of coronary artery stenosis. A cutoff value of 250 confirmed the presence of at least 50% stenosis in symptomatic patients.