Background: Use of arterial grafts in coronary surgery is based on the excellent patency of the left internal thoracic artery (LITA) and an expectation that other arterial grafts-right internal thoracic artery (RITA) and radial artery (RA)-will give similar patencies, superior to saphenous vein. We examined patencies of arterial grafts in a practice with extensive use for more than 15 years.
Methods: Consecutive postoperative angiograms of 2,127 arterial/coronary conduits were evaluated. Angiograms were performed for cardiac symptoms. Assessment was by two observers. String signs were considered as occlusions.
Results: There were 2127 arterial conduits. Overall patencies were as follows: LITA, 96.4% (1296 of 1345); RITA, 88.3% (534 of 605); aortocoronary RA, 89.3% (158 of 177). The LITA patency to the left anterior descending artery was 97.1% (1131 of 1165); to the obtuse marginal artery it was 91.7% (165 of 180; p 0.01). The RITA pedicled graft patency was 86% (275 of 321) compared with free RITA, 91% (259 of 284; p = not significant). For RITA there was a hierarchy of patency for coronary territory grafted (left anterior descending artery best, right coronary/posterior descending artery worst) and for degree of coronary stenosis: if stenosis was less than 60%, patency was 65% (47 of 72); if stenosis was more than 60%, patency was 90.9% (485 of 533; p = 0.0001). Similarly for the radial artery there was higher patency with greater coronary stenosis. The LITA patency at 5 years was 98%, at 10 years it was 95%, and at 15 years it was 88%. The RITA patency at 5 years was 96%, at 10 years it was 81%, and at 15 years it was 65%. The radial artery patency at 1 year was 96% and at 4 years it was 89%. For 3,714 vein grafts also studied overall patency was 61% (2266 of 3214) with patencies of 95% at 5 years, 71% at 10 years, and 32% at 15 years.
Conclusions: Excellent long-term patencies of arterial grafts are noted, superior to those of vein grafts. Patencies were influenced by conduit, by distribution, and by coronary artery stenosis.