[Relation between intraoperative blood flow measurements and graft patency afer aortocoronary bypass surgery]

During aorto-coronary bypass surgery, electromagnetic flow measurements of venous grafts were performed in 50 consecutive patients at rest and after stimulation with papaverine (2 mg) to assess whether early postoperative patency was predictable. The overall patency rate at day 9-11 was 95.4% (145/152 distal grafts; 118 proximal grafts). Flow in all bypass grafts averaged 52.5 +/- 31.4 ml/min and increased after papaverine stimulation by 46.9 +/- 32.2 ml/min (p less than 0.01). 5 of 6 grafts with a flow of less than 30 ml/min and without adequate flow increase after papaverine (less than 80%) were occluded. Grafts with a flow of greater than or equal to 30 ml/min or an increase of greater than or equal to 80% after papaverine, had a high short-time patency rate (98%). Thus, perioperative flow measurements combined with papaverine stimulation predicted early patency of single grafts with an accuracy of 95%.