PolarCath PD System (Boston Scientific) decreases risk of In-stent Restenosis in Diabetic patients

A clinical trial of patients with Diabetes has demonstrated that cryoplasty post-dilitation using the PolarCath Peripheral Dilatation System, from Boston Scientific, compared to conventional balloon angioplasty in the superficial femoral artery (SFA) decreased the risk of In-Stent Restenosis (ISR). Diabetes is associated with increased risk of in-stent restenosis after SFA stenting with nitinol self-expanding stents (nSES). The objective of the COBRA trial was to determine whether cryoplasty post-dilation, when compared to conventional balloon angioplasty, decreases the risk of SFA nSES in-stent restenosis. The primary endpoint was 12 month SFA nSES binary in-segment restenosis, defined as a =2.5 times increase in peak systolic velocity by duplex ultrasound. The rate of occurrence was 55.8% for the conventional balloon group and 29.3% for the cryoplasty group. Cryoplasty significantly reduced 12-month in-stent restenosis compared to conventional balloon post-dilation, according to Subhash Banerjee, Associate Professor of Medicine at The University of Texas Southwestern Medical Center in Dallas, Texas. The PolarCath PD System simultaneously dilates and cools the vessel wall. Cooling to -10oC was achieved by inflating the balloon with nitrous oxide instead of saline and contrast. The system induces smooth muscle cell (SMC) apoptosis, minimizes SMC necrosis (-5 to -15oC) and reduces ISR. Results from the COBRA clinical trial were presented at the 23rd Annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium.