Coronary Computed Tomography Angiography Detects Coronary Stenoses
Coronary CTA may be a reliable imaging alternative to invasive angiography.
Coronary computed tomography angiography (CTA) detected coronary stenoses with an excellent sensitivity and negative likelihood ratio in patients undergoing cardiac valve surgery, according to data published in JACC: Cardiovascular Interventions.
Invasive coronary angiography (ICA) is currently recommended for pre-operative evaluation of coronary artery disease (CAD). However, improvements in CT technology could help detect patients for coronary CTA before valve surgery. Therefore, researchers conducted a meta-analysis to evaluate the diagnostic accuracy of coronary CTA for detecting coronary artery stenoses.
Maksymilian P. Opolski, MD of the Institute of Cardiology in Warsaw, Poland, and colleagues, included 17 studies totaling1107 patients and 12 851 coronary segments in their analysis. All of the studies used ≥16-detector row CT to perform coronary CTA in patients with valvular heart disease who were scheduled for valve surgery. The studies also validated results against invasive angiography.
The patient-based analysis revealed a pooled sensitivity of 93% (95% confidence interval [CI]: 86%-97%) and specificity of 89% (95% CI: 86%-91%). The analysis also showed a negative likelihood ratio of 0.07 (95% CI: 0.04-0.16) and a positive likelihood ratio of 8.44 (95% CI: 6.49-10.99) for coronary CTA to identify individuals with stenosis ≥50%.
Specificity was higher among patients without aortic stenosis compared with those with aortic stenosis (96% vs 87%). Positive likelihood ratio was also higher among patients without aortic stenosis (21.2 vs 7.4). The specificity and positive likelihood ratio were also higher among ≥64 detectors compared with <64 detectors (90% vs 86% and 9.5 vs 6.9, respectively).
In addition, the heterogeneity analysis revealed a significant association between higher specificity of coronary CTA for the detection of significant coronary stenoses and ≥64 detectors, absence of patients with aortic stenosis, younger age, and smaller sample size.
“The present meta-analysis demonstrates that coronary CTA provides, across a wide range of diverse clinical centers, high diagnostic performance for the exclusion of significant coronary stenoses in patients scheduled for valve surgery,” the authors wrote.
“Considering the differences in the pre-test probabilities of CAD among various valvular diseases, the diagnostic accuracy of coronary CTA to detect significant CAD decreased on the background of AS.”
Researchers concluded that coronary CTA using currently available technology can effectively rule out significant coronary stenoses, which suggests that CTA could be used as an alternative to ICA prior to cardiac valve surgery.
“Whereas the image acquisition and reconstruction protocols of coronary CTA are constantly being developed, large-scale prospective clinical trials comparing radiation and contrast exposure between ICA and coronary CTA among patients with valvular heart disease now appear warranted,” they wrote.
Disclosures: Dr Opolski has received scholarship funds from the Foundation for Polish Science. Dr Min has severed on medical advisory boards for various pharmaceutical companies and Dr Achenbach has received grant support and speakers' bureau fees from Siemens Healthcare.
Opolski MP, Staruch AD, Jakubczyk M, et al. Computed tomography angiography for the detection of coronary artery stenoses in patients referred for cardiac valve surgery: Systematic review and meta-analysis. JACC Cardiovasc Imag. 2016. doi:10.1016/j.jcmg.2015.09.028.