When W. L. Gore & Associates (Flagstaff, Arizona) received FDA approval for the Gore TAG Endoprosthesis System in 2005, it was a significant step forward in the treatment of thoracic aortic aneurysms (TAAs), which until then had traditionally been treated with highly invasive open surgery that required a large incision in the patient's chest. In the four years since the device has been approved in the U.S. the company has collected physician feedback and designed a next-generation version of it – the Conformable Gore TAG device that is now being studied in three U.S. clinical trials.
On Tuesday Gore reported the first human implants of the Conformable Gore TAG device. Joshua Rovin, MD, and Eugene Murphy, MD, performed the first implants at Bayfront Medical Center (Saint Petersburg, Florida) as well as William McMillan, MD, and Scott Schultz, MD, at North Memorial Medical Center (Robbinsdale, Minnesota). The devices were used to treat patients with a TAA, which is an enlargement that develops in weakened areas in the thoracic aorta.
Gore said it received an investigational device exemption from the FDA to investigate the use of the device in TAAs. The company said the device has also been approved to investigate endovascular repair of other etiologies including traumatic aortic transection and aortic dissection. Design enhancements include a modified stent frame, repositioned gold bands, and optimized graft material.
David Abeyta, leader of the Aortic business unit at Gore, told Medical Device Daily that the Conformable Gore TAG device is the result of the company's years of experience with its current TAG device and making changes to it based on physician feedback.
"We wanted to take all of that knowledge gained and really build into this next generation device the technology that physicians, and more importantly patients, need," Abeyta said. He added that Gore is "really excited" about the new device being in U.S. clinical trials and is looking forward to being able to "really prove out these changes that we've made" in a clinical study.
As the name suggests, Abeyta said the major difference between the Conformable Gore TAG device and the currently approved device is the flexibility of the new stent graft over the previous version.
One of the things Gore has learned through its experience with the current device and physician feedback is that it was difficult to treat TAAs in highly angulated necks with the device, Abeyta said. The new Conformable Gore TAG device is much more flexible, he said, and more capable of treating those highly angulated necks.
The company also expanded the range of sizes for the new device so that it is able to treat smaller diameter arteries, Abeyta said.
Surgeons who are familiar with the current Gore TAG device who try the Conformable Gore TAG may also notice another change: no more scallops.
Abeyta said the previous version of the device was designed with scallops, which were intended to allow for better sealing and wall apposition. However, since the device has been on the market the company has received physician feedback that those scallops were taking up space and making the landing zone a little bit shorter. Abeyta said the Conformable Gore TAG device was designed without those scallops, which creates a longer landing zone for the device.
Abeyta called this next generation Gore TAG device a step forward, as it is designed to treat other etiologies in addition to TAAs.
"We believe we now have a device that can treat all these etiologies in a way that we didn't understand before when we were designing, basically, an aneurysm device," Abeyta said.
Rovin, a cardiovascular surgeon at Bayfront Medical Center, told MDD that after completing the first two implants with the device, he is "very, very happy with the way the device worked and was able to conform to the aorta," which has been the biggest challenge in treating TAAs, he explained.
"It allows us surgeons then to be able to place the device into aneurysms that might not have been able to be fixed ... before," Rovin said. He also noted that the expanded size range would hopefully allow more patients to be treated with the device.
For example, Rovin said that one of the first two patients treated with the new graft had aneurysms up kind of close, involving the arch of the aorta, which he explained is a "very tight turn." With the new graft, he said he was able to "make that acute turn and stay on the inner curve of the aorta."
William Jordan, MD, from the University of Alabama (Birmingham), will serve as the national principle investigator in the Conformable Gore TAG device in TAA trial. "This study will evaluate device performance across the wide portfolio of sizes available with the next generation Conformable Gore TAG device," Jordan said. The next generation Conformable Gore TAG device portfolio includes device diameters ranging from 21 45 mm as well as tapered devices, and the study will investigate the treatment of patients with aortic diameters of 16 42 mm.
The commercially available Gore TAG Thoracic Endoprosthesis provides a minimally invasive option for safely and effectively treating patients with aneurysms of the descending thoracic aorta. It is comprised of an ePTFE graft with an outer self-expanding nitinol support structure to combine both device flexibility and material durability, Gore said. It received pre-market approval from the FDA in 2005 (Medical Device Daily, March 25, 2005).
Gore said that a TAA occurs slowly, over several years, with little or no symptoms. TAAs are a serious health risk because they can burst or rupture and a ruptured aneurysm can cause severe internal bleeding, which can rapidly lead to shock or death, the company noted. Thoracic aneurysms affect about 15,000 people in the U.S. each year. Some patients may have more than one TAA or may also have an aneurysm in the abdominal aorta, Gore said. Only about 20% to 30% of patients who get to the hospital with a ruptured TAA survive. For this reason, the company says it is crucial to treat aneurysms early in order to prevent their rupture.
"The Gore TAG device has remained the leading option for less invasive treatment of TAA with a proven safety record supported by more than ten years of worldwide clinical data," Abeyta said. "The various clinical trials we are initiating for the Conformable Gore TAG device represent part of Gore's ongoing commitment to provide clinicians with life-saving, minimally invasive solutions."
Amanda Pedersen, 229-471-4212;