The influence of coronary artery bypass grafting to totally occluded coronary arteries on the left ventricular contractility.

Sixteen patients underwent 16 coronary artery bypass grafts (CABG) to totally occluded coronary arteries (TOCA), including 12 left anterior descending coronary arteries (LAD) and 4 right coronary arteries (RCA). Of these 16 CABGs, 2 of the RCA grafts became obstructed postoperatively and the remaining 14 patients with patent grafts were divided into the two following groups: 8 with previous infarcts in the region perfused by the TOCA (Group I) and 6 with no previous infarcts (Group II). The left ventricular (LV) ejection fraction and the mean verocity of circumferential fiber shortening significantly increased postoperatively in both groups and the PLVSP/LVESV significantly increased postoperatively in Group II. The LV segmental wall motion (SWM) in the region of TOCA significantly increased postoperatively in both groups. In 5 of the Group I patients, whose anterior and apical SWM was less than the lowest value of the normal subjects, the anterior and apical SWM significantly increased postoperatively. We thus concluded that CABG to totally occluded LAD results in an excellent graft patency rate, a significant improvement of SWM in the region of the TOCA and global LV contractility, even in patients with severe segmental dysfunction due to previous infarcts.