Diagnostic accuracy of dual-source multi-slice CT-coronary angiography in patients with an intermediate pretest likelihood for coronary artery disease.

AIMS: The aim of the present study was to assess the clinical performance of a dual X-ray source multi-slice CT (MSCT) with high temporal resolution to assess the coronary status in patients with an intermediate pretest likelihood for significant coronary artery disease (CAD) without using negative chronotropic pretreatment. METHODS AND RESULTS: Dual-source CT (DSCT) angiography (Siemens Definition) was performed in 90 patients with an intermediate likelihood for CAD who were referred for invasive coronary angiography. DSCT generated data sets with diagnostic image quality in 88 of the overall 90 patients. In six of seven patients with atrial fibrillation and in 46 of 48 patients with heart rates (HR)>65 b.p.m. image quality was diagnostic. In 20 of 21 patients with at least one stenosis>50% (sensitivity 95%) were correctly identified by DSCT-angiography. In 60 of 67 patients, a lesion>50% was correctly excluded (specificity 90%; positive predictive value 74%). The accuracy to detect patients with coronary stenoses>50% (sensitivity 92 vs. 100%; specificity 88 vs. 91%) was not significantly different among patients with HR>65 b.p.m. (n=46) and <65 b.p.m. The concordance of DSCT-derived stenosis quantification showed good correlation (r=0.76; P<0.001) to quantitative coronary angiography with a slight trend to overestimate the stenosis degree. CONCLUSION: DSCT is a non-invasive tool that allows to accurately rule out coronary stenoses in patients with an intermediate pretest likelihood for CAD, independent of the HR.