Coronary calcium score as gatekeeper for 64-slice computed tomography coronary angiography in patients with chest pain: per-segment and per-patient analysis

Abstract

We sought to investigate the performance of 64-slice CT in symptomatic patients with different coronary calcium scores. Two hundred patients undergoing 64-slice CT coronary angiography for suspected coronary artery disease were enrolled into five groups based on Agatston calcium score using the Mayo Clinic risk stratification: group 1: score 0, group 2: score 1-10, group 3: score 11-100, group 4: score 101-400, and group 5: score > 401. Diagnostic accuracy for the detection of significant (>/=50% lumen reduction) coronary artery stenosis was assessed on a per-segment and per-patient base using quantitative coronary angiography as the gold standard. For groups 1 through 5, sensitivity was 97, 96, 91, 90, 92%, and specificity was 99, 98, 96, 88, 90%, respectively, on a per-segment basis. On a per-patient basis, the best diagnostic performance was obtained in group 1 (sensitivity 100% and specificity 100%) and group 5 (sensitivity 95% and specificity 100%). Progressively higher coronary calcium levels affect diagnostic accuracy of CT coronary angiography, decreasing sensitivity and specificity on a per-segment base. On a per-patient base, the best results in terms of diagnostic accuracy were obtained in the populations with very low and very high cardiovascular risk.

Coronary Artery Calcium Scoring Does Not Add Prognostic Value to Standard 64-Section CT Angiography Protocol in Low-Risk Patients Suspected of Having Coronary Artery Disease

“…Moreover, patients underwent multisection CT for symptom evaluation, and all decisions regarding revascularization were based on symptoms and/or the presence of concomitant ischemia at noninvasive testing followed by invasive coronary angiography ( 18 ). Besides, the presence of obstructive CAD at multisection CT had angiography ( 24 ). Our conclusions may not apply to patients with very high calcium scores.…”

Diagnostic Value of Coronary CT Angiography With Use of Left Coronary Bifurcation Angle in Coronary Artery Disease

“…Low diagnostic specificity and PPV of CCTA in calcified plaques is mainly due to high false positive rates caused by blooming artifacts which result from heavy calcification in the coronary arteries. [11][12][13][14][15] This is a widely known limitation of CCTA. Some recent studies have addressed this issue by showing the improved diagnostic performance of CCTA with use of bifurcation angle measurement when compared to the conventional approach based on coronary lumen stenosis.…”

“…[6][7][8][9][10] It is well known that high calcification or high calcium score in the coronary arteries results in false positive results, thus leading to low specificity and positive predictive value (PPV). [11][12][13][14][15] This limitation has been addressed to some extent with use of image processing methods as reported in some studies. [16][17][18] Another approach to improve diagnostic value of CCTA in the diagnosis of calcified plaques is to use left coronary bifurcation angle as opposed to the conventional method of measuring coronary lumen stenosis.…”

Coronary Artery Calcium Score as a Predictor of Coronary Stenosis in Patients with Diabetes Mellitus

“…Since the introduction of EBCT and the Agatston score, evaluation for the presence of coronary calcium over a period of several years has become a common modality for cardiovascular risk stratification. 1,2) In recent studies, a CACS >400 was associated with an increased risk of significantly obstructive stenosis. [3][4][5][6][7][8][9][10] Berman, et al 11) also noted a significantly higher frequency of perfusion abnormalities at a CACS >400.…”