Diagnostic accuracy of multidetector computed tomography coronary angiography in 330 consecutive patients referred for balloon-expandable transcatheter aortic valve implantation

Abstract

Purpose: The aim of this study was to assess the evaluability and diagnostic accuracy of the multidetector computed tomography (MDCT) coronary angiography in patients referred for transcatheter aortic valve implantation (TAVI). MDCT is playing an increasingly role in patients scheduled for TAVI, providing detailed anatomic assessment of the aortic root and valve annulus and of iliofemoral access. However, the diagnostic performance of MDCT coronary angiography has not been well investigated. Methods: 330 consecutive patients scheduled for invasive coronary angiography (ICA) and 64-slice MDCT for the screening protocol before TAVI were enrolled (42 patients with previous coronary artery bypass graft (CABG), 49 with previous coronary stenting, 233 without previous revascularizations). All MDCT coronary angiography were performed using the same data set dedicated to the standard MDCT evaluation of aortic annulus, obtained with retrospective ECG triggering. Coronary arteries evaluability by MDCT coronary angiography and its diagnostic accuracy parameters in comparison with ICA as gold standard were evaluated. Results: In the remaining 325 patients, the mean HR during the scan was 61±9 bpm. The MDCT evaluability of native coronary arteries was 95.6%. The leading cause of unevaluability was the beam-hardening artifact due to large coronary calcifications (109 cases), followed by slice misalignments (56 cases) due to HR variability or premature heart beats during the scan and motion artifacts (40 cases). In the segment-based analysis, sensibility, specificity, positive predictive value, negative predictive value and accuracy were 91%, 99.2%, 83.4%, 99.6% and 98.8%, respectively. MDCT correctly assessed the patency of all CABG, without graft classified as non evaluable. The MDCT evaluability of coronary stents was 82.1%. In the segment-based analysis, MDCT showed sensibility, specificity, positive predictive value, negative predictive value and accuracy for the detection of ≥ 50% luminal narrowing of 94.1%, 86.7%, 66.7%, 98.1% and 88.3%, respectively. Conclusions: MDCT coronary angiography allows to correctly rule out the presence of significant coronary stenosis in patients referred for TAVI, demonstrating and excellent negative predictive value also in patients with previous CABG or stents.