1Fate of Internal Mammary Artery Grafted to Left Anterior Descending Artery Is Influenced by Native Vessel

than-critical stenosis presented less resistance than the IMA graft, so that distal perfusion preferentially favored the competitive, residual native flow, causing the IMA graft to wither or string.5 However, several reports suggest that even when angiographic patency of the IMA is either greatly reduced or completely absent, the graft may retain physiologically signifi-cant recruitable patency.6,7 Furthermore, Kawasuji et al8 advocated IMA grafting to the left anterior descending artery (LAD) with 50 % proximal stenosis or less because the IMA graft flow in diastole was independent of the grades of native coronary artery stenosis in their intraoperative phasic flow study. The aim of our study was to investigate factors leading to IMA failure or string and to investigat