Intraoperative coronary graft flow determination--does it have a prognostic value for midterm graft patency?

OBJECTIVE: To characterise the prognostic value of intraoperative ultrasonic graft flow determination during CABG for mid-term patency. METHODS: From 01/2000 to 08/2003 3146 CABG procedures were performed at our institution. Graft flow was determined in all patients. Lumen diameter was given in mm and a sclerosis score was applied for the target vessel. 100 of these patients (3.2%) underwent postoperative coronary angiography at a mean time interval of 8.0 +/- 0.5 months. RESULTS: In 100 patients, 114 LITA and 204 venous anastomoses were performed. At re-angiography 112 LITA (98%) and 174 venous (85%) anastomoses were patent. The amount of occluded LITA grafts was to low to perform statistical analyses. Mean graft flow of patent vein grafts was 48 +/- 2 ml/min vs. 32 +/- 4 ml/min in occluded vein grafts (p = 0.001). After multiple logistic regression analysis, only intraoperative vein graft flow was found to be a predictor for patency at mid-term (p = 0.005, odds ratio 0.97, 95% confidence interval (CI) from 0.95-0.99). No differences were found concerning sclerosis scores or vessel lumen between patent and occluded grafts. CONCLUSIONS: Significant differences concerning intraoperative graft flow were found between vein grafts patent or occluded at re-angiography. The predictive power of intraoperative vein graft flow for mid-term patency was confirmed by multiple logistic regression analysis.