[Results of long term surgical treatment of isolated stenosis of the left descending coronary artery].

The results of medical and surgical management of isolated stenosis (greater than or equal to 50%) of the left anterior descending artery were compared retrospectively in a series of 124 consecutive patients. 57 patients were managed medically (Group I). 28 (49%) presented with angina and 36 (63%) with a previous myocardial infarction. The stenosis was greater than 90% in 38 patients (67%) and was associated with severe left ventricular dysfunction in 28 patients (49%). The average ejection fraction was 53.8 +/- 2.5%. 67 patients were managed surgically (Group II): 58 (87%) presented with angina and 28 (42%) with previous myocardial infarction. The stenosis was greater than 90% in 58 patients (87%) and associated with severe left ventricular dysfunction in 19 patients (28%). The average ejection fraction was 61.7 +/- 2.4%. The average length of follow-up was 41.9 +/- 4.1 months in Group I and 46.2 +/- 3.5 months in group II. 6 patients died in Group I, 5 of a cardiac cause, compared to 4 patients (3 of a cardiac cause) in Group II, with an operative mortality of 1.6%. One patient in Group I had a new myocardial infarction compared to 6 in Group II, 3 of which (4.4%) occurred in the perioperative period. Angina regressed after therapy in 23 patients (40%) in Group I and in 48 patients (72%) in Group II (p < 0.01). Angina was unchanged or became more severe in 12 and 5 patients respectively. 34 patients (60%) on drug therapy were able to resume their professional activities as opposed to 26 (42%) in the surgical group (p < 0.05). It would therefore appear that surgery for isolated stenosis of the left anterior descending artery does not significantly reduce mortality, or prevent recurrence of myocardial infarction, but it does significantly improve anginal pain. The same conclusions are obtained when the patients are classified in different sub groups, "operable" patients or those with previous myocardial infarction or with poor left ventricular function. Finally, the surgical indications were "good" in 21 patients, symptomatic with a proximal stenosis greater than 75%, good ventricular contraction on angiography, an ejectionfraction of at least 50%, and good arterial run-off. In these cases surgery was successful with regression of anginal pain in 19 patients (90%) but complicated by secondary infarction in two of them. These results were better than those obtained in the other operated patients, in which the surgical indications were judged retrospectively to have been "inadequate". Therefore, in isolated stenosis of the left anterior descending artery, aorto-coronary bypass surgery should be reserved to patients with "good surgical indications".