Early and Late Clinical Outcomes after Directional Coronary Atherectomy

Background：Restenosis is a major limitation of balloon angioplasty. Recently, new angiop-lasty devices have been used in an attempt to reduce the restenosis compared with coronary balloon angioplasty. Directional coronary atherectomy effectively dilated the lesion by removal of the atherosclerotic plaque. Therefore, we tried to evaluate immediate and late clinical outcomes after directional coronary atherectomy in the 57 patients with coronary artery disease. Methods：From October 1991 to March 1997, fifty seven consecutive patients with 69 lesions were treated with directional coronary atherectomy. The patients underwent coronary angiography at pre-intervention, immediately after intervention and at 6 months post-interven-tion. Restenosis was assessed clinically and by computer-assissted quantitative measurements of luminal dimensions. Patients were requested to undergo coronary angiography at 6 months after directional coronary atherectomy. Angiographic restenosis was defined as more than 50% diameter stenosis by quantitative coronary angiographic analysis. Results：Successful results were achieved in 61 of the 69 lesions(88% and mean stenosis was reduced from 78.0±13.0% to 10.0±5.0%. Atherectomy resulted in an increase in minimal lumen diameter from 0.8±0.3mm to 3.0±0.6mm. Six months follow-up angiogram was obtained in 68% of 50 eligible lesions. The overall angiographic restenosis rate was 32%. Six-month clinical follow-up was obtained in 94% of the eligible lesions. The clinical recurrence occured in 38% of the patients. The target lesion revascularization rate was 17%. Conclusions：Removal of coronary artery plaque with directional atherectomy led to large luminal diameter and six months follow-up angiography shows an overall restenosis rate of 32%. However, further clinical study is warranted to evaluate the efficacy of atherectomy with larger numbers of patients.