Prospective, Randomized Single-center Trial to Compare Cryoplasty Versus Conventional Angioplasty in the Popliteal Artery: Midterm Results of the COLD Study

Purpose: To evaluate safety and efficacy of cryoplasty versus conventional angioplasty for focal popliteal arterial occlusive disease.

Materials And Methods: Patients with focal atherosclerotic stenoses and occlusions of the popliteal artery were randomized to cryoplasty or conventional angioplasty as the initial treatment strategy. The primary objective was target lesion patency. The secondary endpoint was treatment success without the need for stents. Duplex ultrasonography was performed at 3, 6, 9, and 15 months.

Results: Eighty-six patients (mean age, 72 years; age range, 50-94 years) were enrolled in this study. Forty patients were randomized to cryoplasty and 46 to conventional angioplasty. Demographics, risk factors, clinical stage of disease, and lesion details were comparable. On intention-to-treat basis, initial success was 35% for cryoplasty versus 54% for conventional angioplasty (P = .02). The rate of grade C dissection was 35% after cryoplasty and 26% after conventional angioplasty (P = .4). Optional long-term percutaneous transluminal angioplasty (PTA) was performed in 58% of cryoplasty patients. The rate of stent placement for dissection and/or residual stenosis was 30% after cryoplasty (including long-term dilation) and 39% after conventional angioplasty (P = .34). The mean (+/-standard deviation) target lesion patency at 9 months was 79.3% +/- 7.5 for cryoplasty and 66.7% +/-8.1 for conventional angioplasty; however, the results are not significant (P = .14).

Conclusions: Cryoplasty of the popliteal artery alone showed a lower anatomic success when compared with conventional angioplasty. Combined with optional long-term PTA, however, stent placement was not needed more often. There was a trend toward higher patency after cryoplasty, but differences were not statistically significant and results of long-term follow-up have to be awaited.