[Aorto-coronary bypass. 1. Immediate results evaluated in a sample of 357 operated patients]

Over a period of 36 months, 357 patients have had one or several aorto-coronary bypass graft operations, either alone (305 patients) or in combination with another surgical procedure. 230 (66.4%) of these patients had acute coronary insufficiency: unstable angina or "menance syndrome" in 177, Printzmetal's angina in 34, threatened extension of an infarction in 14, and post-cannulation stenosis in 5. 75 patients had chronic coronary insufficiency, and in the 52 others the coronary lesions were associated with valvular or myocardial lesions. A total of 489 grafts were carried out, 261 of which (53.4%) were on the anterior descending artery. Of the 305 patients with grafting and no other surgical procedure, 190 (62,3%) had one single graft, 104 (34.1%) had 2 grafts, and 11 (3.6%) had 3 grafts. For theses 305 patients, the mortality during the first month (6.9%, or 4.5% for the last six months of the series) was influenced by age (a mean of 52.1 in the survivors and 57.1 in the deceased, p less than 0.001), a preoperative infarction less than 8 days old (p less than 0.001), significant changes in left ventricular function (a mean ejection fraction of 44.9% +/- 0.20 in the deceased, and 61.5% +/- 0.19 in the survivors, p less than 0.001), a mean end-diastolic volume of 252 ml +/- 98 in the former and of 136 ml +/- 51 in the latter, p less than 0.001). The advent of a postoperative infarct thus increases the mortality. An infarct complicated the progress of 11.1% of patients. The probability of such a complication occuring depends upon the state of the vascular bed distal to the bypassed artery and on the duration of the extracorporeal circulation.