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

Abstract

Objective Recently, multi-slice CT (MSCT) has emerged as a non-invasive technique that allows to reliably detect coronary stenosis. However, so far the vast majority of MSCT validation studies were performed in high-risk cohorts with a prevalence of significant disease in more than 50% of patients and thus the performance of MSCT in an intermediate risk population remains somewhat unclear. The aim of the present study was to assess the clinical performance of a dual X-ray source 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 From July 2006 until July 2007 we included 37 consecutive patients who were referred to our hospital for coronary angiography for various reasons. All patients had an intermediate pretest probability for CAD according to the scoring method of Morise. All dual-source CT (DSCT) scans were done one day before invasive coronary angiography. No negative chronotropic premedication was used prior to the scan. Results DSCT generated data sets with diagnostic image quality in 36 of the overall 37 patients. In 14 of 15 patients with at least one stenosis >50% (sensitivity 93%) were correctly identified by DSCT-angiography. In 19 of 21 patients, a lesion <50% was correctly excluded (specificity 90%; positive predictive value 87%). In 459 of 501 segments, significant atherosclerotic disease was correctly ruled out (specificity 98%; positive predictive value 74%).The concordance of DSCT-derived stenosis quantification showed good correlation (r=0.75; 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 stenosis in patients with an intermediate pretest likelihood for CAD with a slight trend to overestimate the stenosis degree.