Preoperative coronary angiographic prediction of bypass flow and short-term patency.

A quantitative preoperative coronary angiographic index was defined in 148 patients undergoing coronary revascularization. Each diseased vessel was scored 0-3, for both diameter and quality of run-off. The sum of the scores for diameter and run-off constituted the numerical index for the diseased vessel. Correlations between the index and graft flow measured by electromagnetic flow meter at surgery were established in 259 bypassed vessels. The highest scores (5-6) were associated with higher flows, and the lower scores (0-4) with the lower flows (P less than 0.005). Repeat angiography performed 2 wk postoperatively in 110 patients demonstrated 174 graft patencies and 15 graft closures. Mean flow in open grafts was 82 +/- 41 ml/mn vs. 60 +/- 23ml/mn in closed grafts (P less than 0.005). It is concluded that graft flow is predictable from preoperative Coronary Angiographic Index and that higher flow and index scores are more likely to be associated with graft patency than low flows and index scores.