Coronary Artery Bypass Grafts Assessment at One Year by Noninvasive Multislice Computed Tomography and Invasive Coronary Angiography

Abstract

Objective The aim of this study was to evaluate and compare the postoperative graft patency by multislice computed tomography (MSCT) and invasive coronary angiography (ICA) in patients with multivessel coronary artery bypass grafting at 1 year of surgery. Methods Patients (n = 114) who underwent isolated coronary artery bypass grafting at least 1 year (1.4 ± 0.4 years) previously were subjected to both 16-slice CT angiography with cardiac gating and ICA, and their results were evaluated and compared. All patients were receiving β-blockers; mean heart rate was 64 ± 6 beats/min. Results The mean age of the patients was 59.7 ± 8.5 years. There was a total of 338 grafts (113 internal mammary artery grafts, 8 radial artery grafts, and 217 saphenous venous grafts). On MSCT angiography, all the left internal mammary arteries were visualized with 3D reconstruction. All internal mammary arteries were found to be patent. Twenty-one grafts were occluded or stenosed (21/338, 6.25%). One occluded graft was on the anterior wall (1/20, 0.83%), 11 occluded grafts were on the lateral wall of the heart (11/128, 8.59%), and 9 occluded grafts were on the inferior wall of the heart (9/90, 10.0%); MSCT resulted in no false-positive diagnosis of stenosis (specificity, 100%). However, 2 grafts that were found to be patent on MSCT angiography were blocked on ICA (MSCT sensitivity, 96.3%). Conclusions Postoperative assessment of coronary bypass grafts is possible with an excellent resolution by MSCT angiography. Patency of bypass grafts can be checked by MSCT angiography, and the assessment is comparable with ICA.