Results of the COBRA trial reported at TCT 2011

November 11, 2011

A clinical trial of patients with diabetes has demonstrated that cryoplasty post-dilitation compared to conventional balloon angioplasty in the superficial femoral artery (SFA) decreased the risk of in-stent restenosis (ISR). Results from the COBRA clinical trial were presented today at the 23rd Annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium, sponsored by the Cardiovascular Research Foundation (CRF).

Diabetes is associated with increased risk of in-stent restenosis after superficial femoral artery (SFA) stenting with nitinol self-expanding (nSES). The objective of the COBRA trial (Cryoplasty Or Conventional Balloon Post-dilation of Nitinol Stents For of Peripheral Arterial Segments) was to determine whether cryoplasty post-dilation, when compared to conventional balloon angioplasty, decreases the risk of SFA nSES in-stent restenosis.

Researchers used a cryoplasty dilatation system that simultaneously dilates and cools the . Cooling to -10oC was achieved by inflating the balloon with nitrous oxide instead of saline and contrast. The system induces smooth muscle cell (SMC) , minimizes SMC necrosis (-5 to -15oC) and reduces ISR.

In this prospective, multi-center, randomized clinical trial, 121 patients with diabetes mellitus were enrolled between August 2008 and December 2010 in four clinical sites within the United States. Inclusion criteria included insulin or non-insulin dependent diabetic patients, severe lifestyle limiting claudication (Rutherford category ≥3), chronic critical limb ischemia with rest pain (RB stage 4) or ischemic ulcers (RB stage 5), and SFA lesions requiring nSES ≥5 mm in diameter and ≥60mm in length.

Seventy-four patients with 90 SFA lesions were randomized to cryoplasty (n=45 lesions) or conventional (CBA) (n=45 lesions). Mean age was 64±11.4 years, and 88% were men. Mean hemoglobin A1C was 7.4±1.6 g/dL. The baseline ankle-brachial index (ABI) was 0.59±0.21 and 0.62±0.19 in the cryoplasty and CBA groups, respectively.

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.

"In patients with presenting with life-style limiting claudication, post-dilation of nitinol self-expanding stents in the superficial femoral artery using cryoplasty significantly reduced 12-month in-stent restenosis compared to conventional balloon post-dilation," said Subhash Banerjee MD. Dr. Banerjee is Chief of Division of Cardiology at VA North Texas Health Care and Associate Professor of Medicine at The University of Texas Southwestern Medical Center in Dallas, Texas.

"These results indicate the potential impact of stent post-dilation strategies on endovascular treatment of symptomatic peripheral arterial disease," Dr. Banerjee said.

Explore further: Results of the DEB-AMI Trial reported at TCT 2011

Related Stories

Results of the DEB-AMI Trial reported at TCT 2011

November 10, 2011

A clinical trial that compared the use of drug-eluting balloons (DEB) and bare metal stents (BMS) to both bare metal stents alone and drug-eluting stents (DES) found that the drug-eluting balloon group did not meet the primary ...

Results of the ROTAXUS trial reported at TCT 2011

November 11, 2011

A clinical trial testing the efficacy of rotational atherectomy (or rotablation, a process of drilling through plaque deposits) prior to implantation of a drug-eluting stent found that the process was not superior to standard ...

Results of the REMEDEE trial reported at TCT 2011

November 11, 2011

A randomized comparison of a dual therapy stent – which combines low-dose sirolimus delivery from an abluminal biodegradable polymer matrix with a covalently bound anti-CD34 antibody layer – with a paclitaxel-eluting ...

Recommended for you

Artificial heart design features porous plastic foam

October 2, 2015

Artificial hearts with multiple moving parts increase the chance of failure; scientists have worked up a device which is a single piece. No less interesting is the material they used; the team is taking a page out of soft ...

What powers the pumping heart?

September 25, 2015

Researchers at the Ted Rogers Centre for Heart Research have uncovered a treasure trove of proteins, which hold answers about how our heart pumps—a phenomenon known as contractility.

Sticky gel helps stem cells heal rat hearts

September 24, 2015

A sticky, protein-rich gel created by Johns Hopkins researchers appears to help stem cells stay on or in rat hearts and restore their metabolism after transplantation, improving cardiac function after simulated heart attacks, ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.