Long-term coronary artery graft patency as evaluated by 64-slice coronary computed tomographic angiography

Coronary artery bypass graft (CABG) surgery has been a mainstream surgical procedure for coronary artery disease for the past three decades. 64-Slice coronary computed tomographic angiography (CCTA) has been established as an accurate alternative to invasive coronary artery angiography for postoperative evaluation of bypass grafts. The goal for this study was to utilize CCTA to evaluate long-term graft patency for various graft types as well as their targets.

We analyzed all consecutive patients with a history of coronary artery bypass graft undergoing CCTA over a 3-year period. A total of 827 grafts in 269 patients were included in the study.

Mean survival of the grafts was 21 years (95% confidence interval 20.6, 22.3). The mean survival of grafts to the left anterior descending coronary artery, the left circumflex coronary artery, and the right coronary artery were 22.9, 20.6, and 20.1 years, respectively (P=0.05). Evaluation of graft types demonstrated internal thoracic artery grafts, saphenous venous grafts, and radial artery grafts (RA) had a mean survival of 20.5 years, 21.6 years, and 12.6 years, respectively (P=0.05). Factors significantly affecting the time to closure (P≤0.01) were age [odds ratio (OR) 1.03], male sex (OR 2.39), smoking (OR 2.07), left anterior descending coronary artery graft territory (OR 0.55 compared with right coronary artery), and RA (OR 3.65 compared with thoracic artery grafts, 3.79 compared with saphenous venous grafts).

In conclusion, this study confirms the practicality of using CCTA in a community setting to study bypass graft patency. The choice of graft is significant for long-term patency. This study raises doubt on the long-term fate of RA and further studies should be conducted to better evaluate their outcomes.