Minimally Invasive Procedure OK for Wide Range of Aorta Problems

Tens of thousands of Americans live with a ticking time bomb in their chests. Now, a new University of Michigan study demonstrates that many of them may not need surgery in order to defuse it.

Instead, the research shows, a minimally-invasive procedure can repair a wide range of problems in the upper part of the aorta, the giant blood vessel leading out of the heart. In this region, called the thoracic aorta, the intense force of blood pulsing out of the heart can rip the aorta's walls apart or cause them to balloon outward, eventually leading to a rupture that brings almost certain death.

For decades, patients have had a choice between open-chest surgery and waiting for the "time bomb" to explode. Some haven't had a choice, because their age or health makes them too high-risk for surgery. More than 15,000 Americans die each year from ruptured thoracic aortic aneurysms, dissections and other problems.

But in recent years, a few physicians at U-M and elsewhere have tried an experimental procedure called endovascular thoracic aortic repair, or ETAR, to shore up the aorta without surgery. They've used devices called stent-grafts that are inserted by snaking a long tube up into the aorta from a small incision in the leg or belly. Only in the last year has the U.S. Food and Drug Administration approved the first device designed for this purpose, paving the way for more hospitals to offer it.

Earlier this week, in a presentation at the Society of Thoracic Surgeons meeting, a multi-specialty U-M Cardiovascular Center team gave data from 73 patients who had ETAR at U-M over the last 12 years. Three-quarters of them were considered too high-risk to have surgery. The average survival was nearly four years, and almost half of the patients are still alive today and have not needed additional procedures, though the researchers say close monitoring is needed after a patient has ETAR.

"The minimally invasive approach to major aortic problems promises to revolutionize the way a broad spectrum of patients are treated," says Himanshu Patel, M.D., the lead author of the STS scientific poster. "Even in high-risk patients who would not otherwise be treatable, we see acceptable, encouraging results." Patel, an assistant professor of cardiac surgery at the U-M Medical School, is also chief of cardiovascular surgery at the VA Ann Arbor Healthcare System.

Patel emphasizes the team-based approach used at U-M to treat patients using ETAR. Cardiac surgeons, vascular surgeons and interventional radiologists work together to evaluate patients and determine who should have the minimally invasive procedures, and who would be able have an open-chest operation.

Because ETAR is still relatively new and has not been compared directly with open surgery for aortic conditions, the U-M team uses both approaches depending on patients' characteristics.

But for patients over the age of 80, and those who have stiffened arteries (atherosclerosis), diabetes, lung problems, a history of heart disease or high blood pressure, ETAR may be the only option. And since aortic aneurysms and dissections tend to form later in life and are aggravated by factors such as high cholesterol, smoking and family history, patients are inherently unlikely to be able to withstand open-chest surgery.