Determinants for successful sequential radial artery grafting to the left circumflex and right coronary arteries

The aim of this retrospective observational study was to delineate determinants for antegrade flow and entire patency of the sequential radial artery graft (RAG) in the left circumflex artery (LCX) and right coronary artery (RCA). Angiograms of 432 RAGs, which were sequentially anastomosed to the LCX and RCA, and were proximally anastomosed with the in-situ internal thoracic artery as the composite I- or Y-graft, were studied. The mean targets of RAG were 2.83±0.79. We examined effects of characteristics of RAG and the targets, such as native coronary stenosis and their combinations, on competitive flow and occlusion. Of 432 RAGs, 413 (95.6%) were patent to all targets, while 331 (76.6%) provided antegrade flow to all targets in sequential anastomoses. By the univariate and multivariate analyses, 51-75% stenosis of the most distal target was identified as the significant predictor of competitive flow or occlusion (OR=8.59, P<0.0001). The cumulative graft patency rate of RAGs with 76-100% stenosis of the most distal target at 40 months was 88.6%, whereas that of RAGs with 51-75% stenosis of the most distal target was 59.1% (P<0.0001). In sequential RAG, severity of stenosis in the most distal target had the significant impact on prevention of competitive flow and long-term patency to all targets.