Anatomical and Functional Computed Tomography for Diagnosing Hemodynamically Significant Coronary Artery Disease: A Meta-Analysis

Abstract

OBJECTIVES: This meta-analysis determined the diagnostic performance of coronary computed tomography (CT) angiography (CTA), CT myocardial perfusion (CTP), fractional flow reserve CT (FFRCT), the transluminal attenuation gradient (TAG), and their combined use with CTA versus FFR as a reference standard for detection of hemodynamically significant coronary artery disease (CAD). BACKGROUND: CTA provides excellent anatomic, albeit limited functional information for the evaluation of CAD. Recently, various functional CT techniques emerged to assess the hemodynamic consequences of CAD. METHODS: This meta-analysis was performed in adherence to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. PubMed, EMBASE, and Web of Science were searched from inception until September 7, 2017. Bayesian random effects analysis was used to compute pooled sensitivity, specificity, and the summary receiver-operating characteristic curve of the index tests and compare them with the FFR as a reference standard. Analyses were performed on vessel and patient levels. Because CTA has excellent sensitivity, specificity was considered most relevant. Individual FFRCT values were collected. RESULTS: Overall, 54 articles and 5,330 patients were included. At vessel level, pooled specificity of CTP (0.86; 95% confidence interval [CI]: 0.76 to 0.93), FFRCT (0.78; 95% CI: 0.72 to 0.83) and TAG (0.77; 95% CI: 0.61 to 0.89) were substantially higher than that of CTA (0.61; 95% CI: 0.54 to 0.68). The addition of FFRCT, CTP, and TAG to CTA resulted in high to excellent specificities (0.80 to 0.92). The summary receiver-operating characteristic curve at vessel level yielded superior diagnostic accuracy for CTP, FFRCT, and combined CTA and CTP, compared with CTA. A subanalysis of on-site versus off-site FFRCT revealed no substantial differences between the sensitivity (0.84 vs. 0.85) and specificity (0.80 vs. 0.73) of the 2 techniques. In a second subanalysis, dynamic CTP showed higher sensitivity (0.85 vs. 0.72), but had a lower specificity (0.81 vs. 0.90) than static CTP. CONCLUSIONS: CTP and FFRCT demonstrated a substantial improvement in the identification of hemodynamically significant CAD compared with CTA; therefore, their integration to clinical workflow before revascularization is recommended.