Abstract
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.