A clinical trial under way at The Methodist Hospital in Houston is studying the use of stent grafts to treat thoracic aortic aneurysms in high-risk, emergency situations, such as a ruptured aortic aneurysms or tears in the aorta caused by trauma.

“Our new trial studies the use of a minimally-invasive treatment for patients with serious injuries, offering the potentially life-saving treatment to those who might not be able to withstand the additional trauma of open surgery,” said Dr. Alan Lumsden, principal investigator for the trial and vascular surgeon at the Methodist DeBakey Heart Center.

Research conducted at the Methodist DeBakey Heart Center led to FDA approval of the Gore TAG ™ stent graft for treating low-risk thoracic aneurysms, sparing patients from a highly-invasive surgical procedure that has considerable risks, but the procedure is not yet approved for higher-risk patients who need a less-invasive treatment.

Blunt trauma to the thoracic aorta, the main artery in the chest, is a life-threatening condition that can lead to death in 75 percent of cases at the time of injury, which is often a car accident. Sudden deceleration that often occurs upon impact in a car accident is a classic cause of an aortic tear, or dissection. Of those who survive the initial injury, only half will live beyond the first 24 hours after injury, Lumsden said.

Traditional treatment is surgical repair, which is traumatic to patients who often have multiple injuries to other organs, compounding challenges associated with surgery. The new method can reduce the need for blood transfusions, reduce procedure-related complications such as paraplegia, reduce stress to the heart and lungs, reduce mortality rates and speed recovery times, Lumsden said.

Lumsden and his research team also published an article, Endovascular Treatment of Traumatic Thoracic Aortic Injury -  should this be the new standard of treatment?, for the Journal of Vascular Surgery earlier this year (Vol. 43, Issue 2, Supplement 1, 2/2006).

A stent graft -  which looks like a tube-shaped scaffolding - is inserted into the aorta via the arteries in the groin, similar to the technique of coronary angioplasty. The thoracic stent graft procedure takes place in an operating room or endovascular suite, taking from one to four hours, far less time than the open surgery. The Methodist Hospital has an imaging operating suite specifically designed for these advanced catheter-based procedures.

After the patient is sedated, a small incision is made in the groin area and a sheath is inserted to deploy the stent graft into the aneurysm, creating a seal above and below the tear or ruptured aneurysm. The graft then provides a new pathway, or tube, for the blood to flow.

In this trial a total of 60 patients across the country will be studied and depending on the results, the FDA could approve this procedure for high-risk patients in the coming years.

Methodist Hospital, Houston