Angiographic analysis of immediate and long-term results of PTCR vs. PTCA in complex lesions (COBRA study)

We conducted a prospective, randomized trial to compare immediate and long-term effects of percutaneous transluminal coronary angioplasty (PTCA) and high-frequency rotational atherectomy (PTCR) in patients with angiographically predefined complex coronary artery lesions (AHA type B2 and C). The relation of lesion characteristics to procedural results is reported in this angiographic analysis. Patients were randomly assigned to balloon angioplasty (n = 250 patients) or rotational atherectomy (n = 252 patients). Quantitative coronary angiography could be performed in 447 patients to evaluate immediate results and in 293 patients with a 6-month angiographic follow-up. Procedural success was comparable in the PTCR and in the PTCA group (80% vs. 76%, P = 0.260). The need for stent implantation due to a residual stenosis > 50% or a bail-out situation was significantly higher in the PTCA group (9.7% vs. 2.0%, P = 0.0011. In both treatment groups, diameter stenosis was effectively reduced and MLD increased. The acute gain did not differ between the two groups. At 8-month control, the restenosis rate was comparable in the PTCR and in the PTCA group (37% vs. 35%, P = 0.658), whereas diameter stenosis was significantly more severe in the PTCR group than in the PTCA group (52% vs. 46%, P = 0.039) and, correspondingly, the MLD was significantly smaller in the PTCR group 11.29 mm vs. 1.44 mm, P = 0.031). Late loss was about the same in both groups, however, net gain and net gain index were significantly higher in the PTCA group (0.82 mm vs. 0.64 mm, P = 0.008; acid 31% vs. 24%, P = 0.009). Analysis of procedural results for various lesion characteristics revealed no significant difference between treatment groups. In this randomized trial, complex coronary artery lesions were treated with comparable results for angiographic and procedural success and the restenosis rate by both, PTCA and PTCR. Late loss, however, was significantly higher and net gain significantly smaller after PTCR. Stents, although infrequently used, had a relevant impact on immediate PTCA results but not on late results. (C) 2001 Wiley-Liss, Inc.