PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY OF THE LEFT CORONARY-ARTERY IN PATIENTS WITH CHRONIC OCCLUSION OF THE RIGHT CORONARY-ARTERY - CLINICAL AND FUNCTIONAL RESULTS

The safety and therapeutic benefits of percutaneous transluminal coronary angioplasty of the left anterior descending coronary artery, the left circumflex coronary artery or both were assessed in 61 patients with chronic (> 3 months) occlusion of the right coronary artery. Recanalization of the right coronary artery was not performed before dilatation of left coronary artery lesions. All lesions could be dilated without an acute ischemic event in the catheterization laboratory. However, three patients underwent coronary artery bypass surgery within the first 8 days after coronary angioplasty. There were no in-hospital deaths. Of the remaining 58 patients, 51 (88%) had repeat angiography at a mean of 5.2 +/- 2.5 months. Patients were divided into two groups according to the presence (n = 17) or absence (n = 34) of restenosis defined as greater-than-or-equal-to 50% diameter stenosis at the dilated site. Baseline characteristics were comparable. The mean value for angina functional class at follow-up was significantly better in the group without than in the group with restenosis (0.4 +/- 0.6 vs 2.1 +/- 1.1, respectively; p < 0.001). Sixty-five percent of the patients without restenosis were asymptomatic at follow-up. Seventy-five percent of the predicted maximal physical capacity was reached by 76% of the patients without restenosis compared with 33% in the group with restenosis (p < 0.05). Results of exercise stress tests were clinically positive in 62% of patients with restenosis compared with 12% of patients without restenosis (p < 0.001), and ST-T depression was encountered more frequently in the former (75%) than in the latter group (21%, p < 0.001). Among patients without restenosis, ST-T depression was often found during exercise when regional systolic function was normal or near normal in the myocardial segments depending on the right coronary artery. Left ventricular ejection fraction improved significantly in patients without restenosis at follow-up compared with the baseline value (55 +/- 12% before angioplasty vs 60 +/- 12% at repeat angiography). The difference was not found to be significant in patients with restenosis. Thus in selected patients with chronic occlusion of the right coronary artery, percutaneous transluminal coronary angioplasty of the left coronary artery results in a marked symptomatic improvement in the absence of restenosis, although the procedure provides incomplete anatomic revascularization by design.