Aortocoronary saphenous vein bypass grafts. Long-term patency, morphology and blood flow in patients with patent grafts early after surgery.

Early and late (range 5-73 months, average 2.5 years) postoperative arteriographic studies were performed in 85 patients after saphenous vein aortocoronary bypass surgery.In a prior study (< 2 weeks postoperative) of 570 patients with 1197 grafts, arteriography revealed 89.6% early patency of grafts.Late follow-up in 85 patients discharged with all grafts patent revealed 92.2% still patent, an annual mean graft at- trition rate (percent of grafts closed/year) of 3.2%/year.This mean graft attrition rate was only slightly affected by regrouping patients according to the interval between the two postoperative studies; however, recurrent angina pectoris was influenced by vein graft attrition.Thus, in 36 patients restudied because of recurrent angina pectoris, the attrition rate was 6.1%/year, compared with 1.1%/year in 49 patients without angina.Progressive coronary artery disease (41% vs 18%), graft closure (22% vs 4%) and incomplete revascularization (39% vs 16%) were significantly more frequent in those with recurrent angina.The frequency of progressive coronary disease was directly related to the duration of follow-up (i.e., the longer the follow-up the higher the frequency of progressive disease).The mean annual rate of progressive coronary disease in arteries not grafted was 11.8%/year.Kinking or graft stenosis was observed in 3.1% of grafts in the early study, while late localized graft narrowing was observed in 8%.At late follow-up, most patent grafts were uni- formly narrowed and foreshortened.The mean graft diameter decreased by 17% at late follow-up, and 25% of grafts had at least 25% reduction in mean diameter; however, the mean graft diameter/mean recipient artery diameter ratio exceeded 1.0 in all but one graft.The graft/artery diameter ratio at late follow-up was over 1.5 in 71% of the grafts.The mean graft blood flow determined by cinedensitometric methods revealed a 30% or more reduction in blood flow in 35% of grafts, compared with early postoperative measurements.THE WIDESPREAD APPLICATION of aor- tocoronary bypass surgery in selected patients with coronary artery disease has required both short-and long-term studies to determine the fate of autogenous saphenous vein grafts.It is generally appreciated that coronary bypass surgery is followed by symptomatic improvement; however, it is uncertain whether the sur- gical procedure prolongs life.Information regarding the fate of these grafts in terms of patency, morphologic changes and functional state as a conduit for blood supply to ischemic areas is of paramount im- portance.Serial arteriographic studies'-IO describing both morphologic changes and closure rates in these grafts have been reported, while other studies1 1-7 have described in detail the histologic changes at various times after surgery.The purpose of this report is to describe 2-week postoperative and late arteriographic studies of the early and late patency rate, morphologic changes and bypass flows in saphenous vein grafts in 85 patients.