In a total of 82 patients (age 37-71 years) with an occluded left anterior descending artery (LAD) the results of coronary revascularization were evaluated 7 months postoperatively on average. In all patients the indications for revascularization was given by clinical symptoms (angina pectoris) or by prognostic reasons. In patients with multivessel disease. In patients with anterior wall infarction viable myocardium was proven by thallium-scintigram at rest and during exercise. 29 patients were evaluated by coronary angiography postoperatively, in 19 patients the angiograms of the left ventricle could be assessed quantitatively. Total patency rate was 76%, for the LAD 69%, for the circumflex artery 73% and for the right coronary artery 83%. The relatively low patency rate for the LAD was caused by an increased collateral flow to the occluded LAD and therefore by a significantly lower bypass flowrate measured during surgery. Angina pectoris improved markedly, 55% of patients had angina pectoris class III or IV versus 10% postoperatively. These changes were observed in all patients irrespectively of patency rate or occluded grafts to the LAD. Left ventricular volumes and ejection fraction did not change on average after revascularization. Only end-diastolic volume increased significantly in patients with an occluded graft to the LAD. There was a tendency of the end-systolic volume to decrease postoperatively in patients with complete revascularization or at least an open graft to the LAD. The results show a similar clinical improvement in these patients with occluded LAD as shown after "usual" revascularization in other patients. Preoperative coronary angiograms are helpful in judging the postoperative outcome of grafts to the occluded LAD.