Relation of deep arterial resection and coronary artery aneurysms after directional coronary atherectomy.

OBJECTIVES The aims of this study were to document the frequency of coronary artery aneurysm formation in patients undergoing directional coronary atherectomy and to determine the relation of such aneurysms to the depth of arterial resection. BACKGROUND Deep arterial injury is relatively frequent with the use of directional coronary atherectomy, but the potential for subsequent coronary artery aneurysm formation is unknown. METHODS Results in a consecutive series of 64 successfully treated patients (a total of 69 lesions; mean angiographic follow-up at 5 months) treated with directional coronary atherectomy were retrospectively analyzed with use of quantitative angiographic and histologic data. RESULTS Coronary aneurysms (ratio of dilated vessel segment to the adjacent reference segment > 1.2:1) occurred in seven patients (10%). The only significant clinical correlate of aneurysm formation was a relatively shorter duration of angina. There were no significant preprocedural angiographic predictors of aneurysms, although 6 (86%) of the 7 aneurysmal lesions arose from restenosis lesions compared with 30 (48%) of 62 lesions with no subsequent aneurysm development (p = 0.06). Histopathologic examination of 414 specimens from 68 treated lesions showed no significant difference in the occurrence of subintimal resection (media +/- adventitia) between those with and without subsequent aneurysm (29% vs. 22%). Media alone was found in 14% of specimens from lesions that later became aneurysmal versus 15% of those that did not; adventitial resection was found in 14% and 7% of specimens, respectively (p = 0.08), with relatively more adventitia per specimen from those with aneurysm (55% vs. 30% without aneurysm, p = 0.08). CONCLUSIONS Aneurysms occur relatively frequently after directional coronary atherectomy. Although there was no statistically significant correlation with the depth of arterial resection, the evidence from this study suggests that the role of adventitial resection in the occurrence of late aneurysm development should be explored further.