Comparison of rotational atherectomy with conventional balloon angioplasty in the prevention of restenosis of small coronary arteries: Results of the Dilatation vs Ablation Revascularization Trial Targeting Restenosis (DART)

Abstract

BackgroundThe optimum treatment of obstructive coronary disease in small (<3.0 mm diameter) arteries remains unknown. Rotational atherectomy is an approved treatment that might reduce the vascular injury during percutaneous coronary intervention compared with angioplasty. We report on a multicenter, randomized, blinded end point trial comparing rotational atherectomy with balloon angioplasty in the prevention of restenosis of obstructed small coronary arteries. MethodsA total of 446 patients with myocardial ischemia associated with an angiographic stenosis in a native coronary artery 2 to 3 mm in diameter and ≤20 mm in length without severe calcification were randomly assigned to receive rotational atherectomy (n = 227) or balloon angioplasty (n = 219). The primary end point was target vessel failure at 12 months (defined as the composite of death, Q-wave myocardial infarction, and clinically driven repeat revascularization of the target vessel). ResultsThe mean reference vessel diameter was 2.46 ± 0.40 mm, the mean lesion length was 9.97 ± 5.59 mm, and the prevalence of diabetes mellitus was 32%. Acute procedural success (91.6% for rotational atherectomy, 94.1% for balloon angioplasty, P = .36) and target vessel failure at 12 months were not significantly different (30.5% vs 31.2%, P = .98). At 8 months, there were no significant differences in minimum lumen diameter (1.28 ± 0.63 mm vs 1.19 ± 0.54 mm, P = .26), percent diameter stenosis (28% ± 12% vs 29% ± 15%, P = .59), binary restenosis rate (50.5% vs 50.5%, P = 1.0), or late loss index (0.57 vs 0.62, P = .7). No Q-wave myocardial infarctions occurred in either arm of the study, and non–Q-wave myocardial infarctions (defined as creatine kinase level >2 times normal with an elevated creatine kinase-myocardial band isoenzyme level) occurred in 2.2% and 1.4% of the patients in the rotational atherectomy and balloon angioplasty groups, respectively (P = .72). ConclusionRotational atherectomy was found to be safe in the treatment of obstructed small arteries, but lower rates of target vessel failure were not achieved compared with balloon angioplasty. Because the acute gain and loss index ratios of the 2 treatments were similar, there was no evident beneficial antirestenosis mechanism seen for rotational atherectomy.