The FDA has approved a new device that would be only the second product on the market available to treat thoracic aortic aneurysms (TAA) other than traditional open surgical repair.

Cook Medical's (Bloomington, Indiana) Zenith TX2 Thoracic TAA Endovascular Graft is indicated to treat patients with aneurysms or ulcers of the descending thoracic aorta having vascular morphology suitable for endovascular repair.

"This really offers to that group of patients an alternative to open surgery, which allows them to return to normal lifestyles quicker," Cook Vice President Barry Thomas told Medical Device Daily. "If you have a thoracic aneurysm, physicians typically would have to open the chest. It's a very invasive operation with a significant death rate. With the Zenith device, we basically make little incisions into the femoral artery and the device is introduced through a catheter system."

He added that the procedure can be performed in about an hour and patients may have a hospital stay of a couple of days, compared to a week's stay with open surgery.

Cook sponsored the STARZ-TX2 clinical trial, a multi-national trial designed to study the safety and effectiveness of the Cook Zenith TX2. Those results indicated that the thoracic endovascular aortic repair (TEVAR) procedure, using Zenith TX2, is a safe and effective alternative to open surgical repair for the treatment of TAAs in patients with suitable anatomy.

TAAs occur when a section of the thoracic aorta weakens and bulges outward like a balloon. Ruptured aneurysms have a very high mortality rate.

The Zenith TX2, a self-expanding tube of surgical graft material reinforced with metal stent bodies, is sized to the diameter of the aorta and is used to seal off the aneurysm. It includes an uncovered distal stent with fixation barbs to hold the device in place, which helps to relieve pressure on the aneurysm and reduce the risk of rupture, and in most cases, allow the aneurysmal sac to shrink.

Cook expects to start product roll-out in June, but first must train physicians on how to use the device. Thomas said the majority of the training is centered on helping physicians to select the correct size. "They choose a size relative to the size of the patient's aneurysm," he said, adding that is done with help from CT scans.

"Then, after some training, we hope to be in full swing of the roll-out by July," he said.

According to the American Medical Association (Chicago), 15,000 people die annually as a result of TAA. In addition, 5% to 10% of those who die of sudden death (roughly 200,000 annually) are estimated to have died as a result of TAA, which brings the number of deaths up to an estimated 30,000 each year.

"These patients are, predominantly, over 65 years of age and 60% are men. Smokers are more prone than non-smokers," Thomas said.

The only other product available for this treatment is W. L. Gore & Associates' (Flagstaff, Arizona) Gore TAG Thoracic Endoprosthesis. TAG is inserted through a small incision in the patient's groin, and a catheter delivery system is guided into position through the patient's arteries under fluoroscopy.

Once in position, a reinforced ePTFE- (expanded polytetrafluoroethylene) covered, self-expanding nitinol stent is secured inside the weakened section of the thoracic aorta. This creates a new path for blood flow and relines the aorta. The stent-graft excludes the diseased segment from the pressure of blood circulation, thereby reducing the risk of a rupture.

"Essentially the difference between the two [Gore TAG and Zenith] is in the design of the graft itself," Thomas said. "We have fixation associated with our graft. When it's situated in the aorta, the small spikes hold it into the aorta, which resists migration."

Thomas estimates the market potential for Cook's product to be about $300 million.