New catheter device for abdominal aortic aneurysm

William E. Sorfleet had a life-threatening abdominal aortic aneurysm, but at age 82, he was too old for major invasive surgery to repair the bulging blood vessel.

So vascular surgeon Dr. Ross Milner of Loyola University Hospital repaired the aneurysm with a catheter device instead of a scalpel. The catheter, inserted through an artery, deployed a device called a stent graft that repaired the aneurysm.

Sorfleet, who lives in Woodridge, Ill., is among the patients participating in a nationwide clinical trial to evaluate the device. He went home the day after the procedure.

"I feel great," he said.

An abdominal aortic aneurysm is a bulge in the aorta, the major blood vessel that extends down to the abdomen. A large aneurysm is like a ticking time bomb. At any time, it could suddenly burst, causing massive internal bleeding that is usually fatal. About 15,000 people in the United States die each year from such ruptures.

A stent graft is a Dacron tube supported by a metal webbing. It is put in place by a catheter (thin tube). Milner inserted the catheter in a groin artery, and guided it to the aneurysm. After he deployed the stent graft from the catheter, the device expanded outward to the walls of the artery. Blood now flows safely through the tube-like stent, rather than through the bulging aneurysm.

In recent years, vascular surgeons have treated an increasing percentage of aneurysms in the chest and abdomen with stent grafts. But Sorfleet had a difficult-to-treat aneurysm. The bulge, more than 2 inches wide, contained a ring of calcium deposits and therefore could not be treated with any of the four stent grafts now on the market.

Milner used a stent graft that is being evaluated in a clinical trial. (Loyola is the only center in Illinois participating in the trial.) The device, called UniFit®, is made by LeMaitre Vascular Inc.

Stent grafts now on the market can repair aneurysms in between 60 percent and 70 percent of AAA patients, Milner said. He estimates that an additional 10 percent to 15 percent of patients potentially could benefit from the new stent graft.

The aorta is the largest blood vessel in the body, and is roughly the width of a garden hose. The stent graft Milner used is 5.5 inches long and nearly an inch in diameter at its widest point.

"I felt no pain," Sorfleet said. "This is working great for me."

Milner heads a team of researchers at Loyola who are conducting clinical trials on stent grafts and other minimally invasive treatments for aortic aneurysms and other vascular diseases.

They are testing new devices designed for endovascular surgery, which is significantly less invasive than traditional open surgery. In endovascular surgery, the surgeon guides a catheter through blood vessels to reach and treat the diseased area. Patients recover more quickly, with fewer complications and smaller scars.

"This clinical research program will expand our ability to take care of our patients and add to our overall mission," Milner said.