Support for using CT for coronary artery plaque detection
MedWire News: Computed tomography (CT) should be considered the primary noninvasive test for detection and analysis of coronary artery plaques, say investigators.
Compared with intravascular ultrasound (IVUS), the current standard, CT provides high sensitivity and specificity in the detection of any coronary artery plaque, report the researchers.
"IVUS allows for cross-sectional imaging of coronary arteries and a comprehensive assessment of coronary atherosclerotic plaques," say Dengfeng Gao and colleagues, from Xi'an Jiaotong University School of Medicine in Shaanxi, China.
However, it cannot be used for routine evaluation of plaque characteristics because of its invasiveness and the related increased risk during the procedure, additional time required, and associated costs.
"CT is a novel noninvasive test for detection and analysis of coronary artery plaques," the team explains. However, "the ability of CT to detect and quantify coronary atherosclerotic plaque in vivo has never been systematically validated."
The researchers therefore performed a meta-analysis of published studies (from 1966 through January 2011) to evaluate the potential diagnostic value of CT in detecting coronary plaques.
In total, 17 studies were included in the analysis; seven used a 16-slice CT scanner, seven used a 64-slice scanner, one used a dual-source scanner, and one involved two different types of scanners, a 64- and 320-slice CT.
Among these reports, the pooled sensitivity and specificity for CT was 92% and 93%, respectively, compared with IVUS.
The sensitivity and specificity was affected by plaque composition, reports the team; CT had a higher diagnostic sensitivity and specificity for calcified plaques (93% and 98%, respectively) than for noncalcified plaques (88% and 92%, respectively).
Of note, the researchers found significant heterogeneity in results among the included studies. This may be explained by the use of meta-regression, they say, or by the different generations of scanners included. Indeed, the sensitivity for scanners with more than 16 detector rows was significantly higher than that for scanners with 16 rows or less, at 94% versus 85%.
Writing in the journal Atherosclerosis, the team says: "CT should be considered the foremost noninvasive alternative to IVUS for detecting coronary artery plaques.
"Randomized studies at the patient level are needed to address the potential use of CT in triage to alter management and outcomes in patients with high risk, suspected, or onset coronary artery disease."
By Nikki Withers