[Obstruction of the left coronary branch. Ergometric, hemodynamic and angiographic findings].

The authors present 6 personal cases of complete obstruction of the left main stem coronary artery and review the main epidemiological, clinical, ergometric, haemodynamic, angiographic and therapeutic data concerning this condition which is uncommon (0.66% of patients who underwent coronary angiography for angina in this series). This series had a number of special features. Clinical symptoms were moderate, consisting of exercise-induced aggravated angina, except in one patient with a history of anterior infarction complicated by regressive initial heart failure with residual angina. For this reason, all patients were able to perform a standard exercise-test on an ergometric bicycle without any problem. As the exercise test revealed major abnormalities, extreme precautions were observed when coronary angiography was performed, but no incident occurred in any of the 6 patients. Haemodynamic data were normal in 4 cases and altered in 2 cases. The important role played by collateral circulation must be stressed; it is probably under evaluated at arteriography. The absence of lesion of the right coronary artery is thought to facilitate the development of a collateral vascular network. Five patients were operated upon, made an uneventful recovery and were followed up for 19, 42, 17, 5 and 2 months respectively: all were symptom-free under medical treatment. In 3 out of these 5 patients who underwent a post-operative exercise-test all parameters showed excellent results; however, the 4th patient proved unadaptable to exercise, and ECG showed persistent ischaemia due to a very poor distal coronary bed; in the 5th patient, under diltiazem, the results on ischaemia and on the circulatory signs of heart failure were very good.(ABSTRACT TRUNCATED AT 250 WORDS)