The chronic coronary flow reserve provided by saphenous vein bypass grafts as determined by digital coronary radiography.
Intraoperative measurements following aortocoronary revascularization have demonstrated a reduced coronary flow reserve (CFR) in saphenous vein bypass grafts. To determine whether chronic bypass graft flow reserve returns to normal, we studied patients in the cardiac catheterization laboratory by means of a newly developed digital coronary radiographic technique. CFR ratios were determined for 54 arterial distributions from 33 men. Twenty-two distributions were normal (group I) 22 had saphenous vein bypass grafts (group II), seven had high-grade stenoses, which were subsequently bypassed (group III), and three were bypassed but had flow-limiting stenoses (group IV). Group II arteries had approximately half the CFR of group I arteries (1.40 +/- 0.17 vs 1.78 +/- 0.31; p less than 0.0001) but significantly improved CFR compared to group III arteries (1.40 +/- 0.17 vs 1.05 +/- 0.13; p less than 0.002) or group IV arteries (1.40 +/- 0.17 vs 1.05 +/- 0.12; p less than 0.02). These results indicate that regional CFR is improved by nonstenotic saphenous vein bypass grafts but does not return to normal.
D000328:Adult; D002933:Cineradiography; D003201:Computers; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012501:Saphenous Vein / Q000000981:diagnostic imaging / Q000637:transplantation