Assessment of Coronary Artery Bypass Graft Patency by Multislice Computed Tomography

Abstract

The recently developed multislice computed tomography (MSCT) is capable of rapid imaging of cardiac structures, including coronary arteries, during a single breath-hold. We evaluated coronary artery bypass graft (CABG) patency by comparing MSCT results to those of contrast angiography. MSCT and contrast angiography were performed in 39 patients (10 women, 29 men and mean age 60.0 ± 7.8 years) with a total of 115 bypass grafts including 36 left internal mammary arteries, 4 right internal mammary arteries, 19 radial arteries, 2 gastroepiploic arteries and 54 vein grafts. Patients were investigated for an average of 14 ± 27 months (range 1 - 108 months) after CABG surgery. Contrast angiography showed a patency rate of 87.0% (100/115). Ninety-nine of these 100 patent grafts by contrast angiography and 14 of the remaining 15 occluded grafts were correctly classified by MSCT (93.3% sensitivity and 99.0% specificity for bypass graft occlusion). The positive and negative predictive values for bypass graft occlusion were 93.3% and 99%, respectively, with an overall diagnostic accuracy of 98.3% (97.2% for left internal mammary artery, 100% for radial artery, 98.1% for vein graft and 100% for other grafts). In conclusion, MSCT is a useful and accurate diagnostic tool for the evaluation of bypass graft patency.