University of Chicago surgeons use novel devices to repair abdominal aortic aneurysms

March 13, 2000

An 85-year-old Chicago man, an avid golfer from Michigan, a prominent North Side lawyer, and the CEO of a leading printing company are back in action thanks to two different teams headed by University of Chicago vascular surgeons and two slightly different versions of a metal and fabric device known as an aortic stent graft. These devices, which were recently approved by the Food and Drug administration (FDA), are designed to replace the dilated and weakened wall of the body's largest artery.

All four patients had been diagnosed with abdominal aortic aneurysms--balloon-like swelling of the aorta, the main vessel supplying blood to the lower body. Over time, an aneurysm can expand and eventually rupture, triggering sudden and often fatal blood loss.

Approximately 13,000 people in the United States die each year from ruptured aortic aneurysms and another 45,000 undergo surgical repair. Standard treatment involves a major operation with a large abdominal incision, potential loss of blood requiring replacement transfusion, a five to 10 percent complication rate and a two to four percent risk of death from the procedure. Patients are generally in the hospital seven to 10 days and require two to three months to fully recover at home.

All patients treated at the Hospitals with aortic stent grafts, however, have gone home after one or two days, without the big scar or the associated pain. They have been able to return to their normal routine in a very short time.

"There is no comparison between the stress of major invasive surgery and the relatively minor discomfort involved with placing a stent graft," said vascular surgeon Jim McKinsey, MD, assistant professor of surgery at the University of Chicago, who performs both open and minimally invasive procedures. "The patients are able to leave the hospital after a day or two in basically no pain and able to rapidly return to their normal lifestyle. The main concern with the minimally invasive approach is the lack of data on how it will perform in the long-term."

Instead of opening the abdomen to replace the enlarged segment of the aorta with a conventional graft, a stent graft can be put in place using a thin, flexible wire inserted through two small incisions in the groin. Physicians thread a guide wire from the groin up into the aorta. The stent graft is then positioned across the weak spot in the aorta. Once in position, the device expands and attaches to the healthy portions of the artery--above and below the damaged areas--sealing off the diseased region while permitting normal blood flow to continue through the artery and the graft.

University of Chicago Hospitals surgeons are studying whether they can safely and effectively repair abdominal aortic aneurysms through this minimally invasive approach with fewer complications than open surgery, which involves replacing the weakened section of the affected artery with an artificial bypass graft. The new method is expected to lower the risk of death, decrease the chance of requiring a blood transfusion, eliminate the need for intensive care, shorten hospital stays, allow for a rapid return to work, and decrease healthcare costs. It should also provide a new treatment option for patients too ill to undergo major surgery.

"This is still a new field and the technology is evolving rapidly," added Hisham Bassiouny, MD, associate professor of surgery and chief of vascular surgery at the University of Chicago's Weiss Memorial Hospital on the North Side. "Placing a stent used to require several hours, but the newer modular devices can be slipped into place quite quickly and with impressive precision."

"Most people who have aneurysmal disease are older and have other medical problems that increase the risk of surgery, added Dr. Bassiouny. "So for them, this can be a life-saving option." The procedure is so promising that a dedicated "endovascular suite" is under construction at the University of Chicago Hospitals. This specialized operating room will combine the standard vascular surgical equipment with state of the art catheterization and X-ray equipment, providing the optimal environment for minimally invasive repair of diseased blood vessels.