CTCA for detection of significant coronary artery disease in routine TAVI work-up : A systematic review and meta-analysis

Abstract

Transcatheter aortic valve implantation (TAVI) has evolved to standard treatment of severe aortic stenosis in patients with an intermediate to high surgical risk. Computed tomography coronary angiography (CTCA) could partially replace invasive coronary angiography to diagnose significant coronary artery disease in the work-up for TAVI. A literature search was performed in MEDLINE and EMBASE for papers comparing CTCA and coronary angiography in TAVI candidates. The primary endpoint was the diagnostic accuracy of CTCA, compared to coronary angiography, for detection of significant (>50% diameter stenosis) coronary artery disease, measured as sensitivity, specificity, positive-(PPV) and negative predictive value (NPV). Seven studies were included, with a cumulative sample size of 1,275 patients. The patient-based pooled sensitivity, specificity, PPV and NPV were 95, 65, 71 and 94% respectively. Quality assessment revealed excellent and good quality in terms of applicability and risk of bias respectively, with the main concern being patient selection. In conclusion, on the basis of a significance cut-off value of 50% diameter stenosis, CTCA provides acceptable diagnostic accuracy for the exclusion of coronary artery disease in patients referred for TAVI. Using the routinely performed preoperative computed tomography scans as a gatekeeper for coronary angiography could decrease additional coronary angiographies by 37% in this high-risk and fragile population.

Keywords: Aortic stenosis; Computed tomography coronary angiography; Coronary angiography; Coronary artery disease; Diagnostic accuracy; Transcatheter aortic valve implantation.

Fig. 1

Flowchart of selection process. Scheme, depicting study identification and selection process. (CAD coronary artery disease, CAG coronary angiography, CTCA computed tomography coronary angiography, TAVI transcatheter aortic valve implantation)

Fig. 2

Methodological quality assessment of included studies by QUADAS II. Summary of quality assessment. Low, high or unclear risk of bias or concerns regarding applicability is represented by green, red or blue respectively. (QUADAS-2 Quality Assessment of Studies of Diagnostic Accuracy Included in Systematic Reviews 2)

Fig. 3

Diagnostic accuracy paired forest plot. Sensitivity and specificity of CTCA versus CAG for the detection of CAD in patients receiving TAVI. Results are depicted in a paired forest plot, with resulting confidence intervals for each individual study and for the studies combined

Fig. 4

Flow and timing. Scheme, depicting the timing of the pre-procedural CTCA and CAG before TAVI. (CTCA computed tomography coronary angiography, CAG coronary angiography, NR not reported, TAVI transcatheter aortic valve implantation procedure)

Fig. 5

Summary receiver operator curve plot, bivariate model. Sensitivity versus false positive rate is plotted in a for all included studies. Each study is represented by a coloured circle, size being dependent on study size. The black square represents the summary estimate. The thick dashed lines represents the 95% confidence region (Conf. Region) and the thin dashed line represents the 95% summary region (Summ. Region). (SROC summary receiver operator characteristic curve, Sym symbol)