Early graft patency after off-pump and on-pump coronary bypass surgery: a prospective randomized study

Uncertainty persists regarding the impact of the off-pump technique on coronary bypass graft patency. The primary objective of this study was to assess coronary artery bypass graft patency in patients randomized to off-pump and on-pump multivessel coronary artery bypass grafting (CABG). Secondary objectives were clinical outcomes and neuropsychological functioning.

One hundred and fifty patients were randomized to off-pump (n = 75) or on-pump CABG (n = 75). Graft patency was assessed by multidetector computed tomography 5 weeks after surgery. The two groups were similar regarding patients' characteristics and logistic Euroscore (3.6 vs. 3.7%). Mean number of grafts performed was 3.5 ± 0.6 and 3.5 ± 0.6 in off-pump and on-pump, respectively (P = 0.7). Raw graft patency rate was 89.9% in off-pump and 95.0% in on-pump (OR 2.2, 95% CI 1.07-4.44; P = 0.03). Nineteen (27%) off-pump and 9 (13%) on-pump patients had at least one occluded graft (P = 0.04) and the proportion of patent grafts per patient was 0.91 ± 0.2 in off-pump vs. 0.96 ± 0.1 in on-pump (P = 0.06). However, after adjusting by heparin dose, graft patency was not statistically different between groups (OR 0.87, 95% CI 0.25-2.98, P = 0.83). At 30 days, there was no statistically significant difference in major adverse events and neuropsychological functioning between off-pump and on-pump groups. One-year follow-up showed similar functional class and positive treadmill exercise tests.

Under the conditions this trial was conducted, CABG performed off-pump had lower overall graft patency rate than on-pump, which was not statistically different after controlling for total heparin dose. Thirty-day complications, neuropsychological functioning, and one-year clinical and functional outcomes were not statistically different between the two techniques.