Directional coronary atherectomy for lesions of the proximal left anterior descending artery: initial clinical results, complications and histopathological findings.

Abstract

Directional coronary atherectomy is a percutaneous technique which extends the role of balloon angioplasty to bulky eccentric coronary lesions. To report the early experience, clinical results, complications and histopathological findings of directional coronary atherectomy (DCA) in proximal left anterior descending artery (LAD) stenosis. Study of 25 lesions in 24 patients on whom directional atherectomy was performed on the proximal LAD artery with the Simpson coronary atherectomy device. Twenty-five procedures were performed on 24 patients with stenosis in the proximal LAD artery. There were 21 males and three females with a mean age of 56.5 years. Sixteen patients presented with stable angina and eight with unstable angina. Eight patients had previous myocardial infarction (MI). Angiographic success was obtained in 24 of 25 lesions (96%). The mean lesion length was 13.1 +/- 3.7 mm and the mean LAD artery diameter was 3.6 +/- 0.5 mm. Minimal luminal diameter improved from 0.9 +/- 0.4 mm to 3.0 +/- 0.5 mm and the percentage diameter stenosis reduced from 75 +/- 12% to 16 +/- 9%. Complications included acute occlusion in one patient, non-Q MI in three patients, local vascular complications in one patient and side-branch loss in one patient. Histology demonstrated fibrous cap of atherosclerotic plaque in 100%, media and internal elastic lamina in 28% and intimal hyperplasia in 100% of restenotic lesions and 27% of native lesions. Restenosis rates in angiographically restudied patients was 27%. The mean minimal luminal diameter at follow-up was 2.3 +/- 0.9 mm and the mean percentage diameter stenosis was 35 +/- 21%. From this initial study, we conclude that DCA is an effective and safe procedure for the treatment of large proximal LAD lesions. DCA provides a large luminal diameter and "smoother' angiographic appearance compared to coronary angioplasty. Acute complication rates are low and restenosis rates were comparable with percutaneous transluminal coronary balloon angioplasty.