[Coronary artery bypass grafting in patients with severe left ventricular dysfunction: internal mammary artery vs...

Comparative studies of the changes in left ventricular (LV) function immediately after aortocoronary bypass graftings (CABG) and early postoperative results were carried out in two groups of patients with severe LV dysfunction (ejection fraction less than 0.4), which consisted of 9 patients received internal mammary artery grafts (IMAG) to at least LAD and 14 with saphenous vein grafts (SVG) only. The utilization of IMAG was limited to the patients with stable preoperative hemodynamics, whereas SVGs were used even in the emergency CABG. Free flow of IMAG measured during operation was 55.7 +/- 25.5 ml/min, which was significantly lower than that (83.5 +/- 27.3) of SVG to LAD. Cardiac index, LV stroke volume index and LV stroke work index immediately after surgery were sufficiently maintained and recovered almost similarly in both groups. Postoperative peak CK-MB (19.7 +/- 10.4 IU/L) in IMAG group was significantly lower than that (23.9 +/- 10.7) in SVG group. There was no significant difference between the two groups in the incidences of postoperative IABP and noradrenaline dependence. There were two hospital deaths in SVG group, whereas no hospital death was experienced in IMAG group. These results indicate that an application of IMAG to LAD in the patients with severe LV dysfunction surely induces satisfactory recovery of hemodynamics immediately after CABG as well as SVG, provided that use of IMAG is limited to the patients with stable preoperative hemodynamics.