Clinical, angiographic and histopathological predictors of restenosis after directional coronary atherectomy.

Out of 127 directional coronary atherectomy (DCA) procedures done in our laboratory, there were 81 patients who had completed a minimum of six months of follow-up. To study the factors predisposing restenosis after successful DCA, we analysed the clinical and angiographic profile of the patients and the histopathological findings of the excised tissue in 44 patients whose complete follow-up data was available with us. The indication of DCA was an extremely eccentric significant stenosis located in the proximal or midsegment of a large vessel (> or = 3 mm size) in 97 percent of the cases. Angiographic restenosis, defined as more than 50 percent luminal diameter stenosis was absent in 24 (54.5%, Group A) and present in 20 (45.5%, Group B) patients. On univariate analysis, the factors which predisposed to restenosis were: (i) left anterior descending location, (ii) longer lesion length (9.6 +/- 3.1 mm vs 5.2 +/- 1.6, p < 0.01) and (iii) greater post-procedure residual luminal diameter stenosis (13.1 +/- 10.8% vs 4.3 +/- 6%, p < 0.01). No significant difference was found between the two groups for other variables like unstable angina, the location and the morphological characteristics of the lesion and the ratio of the vessel diameter to the size of the Atherocath. Histopathological examination of the retrieved tissue revealed the presence of media with or without external elastic lamina in 8 (33%) patients in Group A--without restenosis compared to only 1 (5%) patients in Group B--with restenosis (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)