Endovascular Repair for Aneurysm Rupture

BY KAREN M. DENTE, M.D.

NEW YORK -- The benefit of doing emergency endovascular aneurysm repair of ruptured abdominal aortic aneurysms seems unclear, although results from single-center studies as well as data from a global registry indicate that the procedure may significantly reduce mortality, compared with open surgical repair.

Dr. Frank J. Veith reviewed worldwide data on endovascular repair for ruptured thoracic and abdominal aortic aneurysms.

Dr. Frank J. Veith presented the collected worldwide experience on endovascular repair from 48 centers at the Veith symposium on vascular medicine sponsored by Montefiore Medical Center.

A total of 442 cases of ruptured AAAs and 221 ruptured thoracic abdominal aneurysms (TAAs) were treated with an endovascular graft (EVG), according to Dr. Veith, who is chair of vascular surgery at Montefiore Medical Center and professor of surgery at Albert Einstein College of Medicine, both in New York.

Of the 442 patients receiving an EVG for a ruptured AAA, 364 patients survived beyond 30 days, with an 18% procedural mortality. Of the 221 patients with ruptured TAAs who underwent the procedure, 182 survived past 30 days, also with an 18% procedural mortality.

The mortality rates associated with endovascular aneurysm repair compared favorably with that of open surgery, which has a mortality rate of 40%-60%.

"We think it's an improvement in mortality. Many of our cases could not have been operated on. They were too sick, and we saved them," said Dr. Veith.

Many of the patients in the global registry were hypotensive, some had free intraperitoneal or intrapleural ruptures, and many had prohibitive risks for open surgical repair.

Endovascular aneurysm repair to exclude AAA was introduced in the early 1990s for patients of poor health status considered unfit for major surgery.

"Traditionally, open surgery has been the choice surgical option to treat AAAs. However, the elderly and patients with comorbidities could be best served by having an endovascular surgical repair. EVAR avoids many dangers associated with open surgery," said Dr. Veith.

Uncertainty still remains as to whether single-center results for emergency EVAR show a selection bias in favor of EVAR. Dr. Veith stated that the results for the global registry are based on a selected group of patients.

"In some of the centers, they only did certain patients, which varied from center to center," he explained. EVGs were employed in 18%-76% of all patients seen at each center with ruptured AAAs or ruptured TAAs. At Montefiore Medical Center "everybody was a candidate," according to Dr. Veith, "with 76% of the cases done endovascularly."

The mortality rate following treatment of ruptured aneurysms at Montefiore Medical Center was 11%, according to Dr. Veith.

"There is an irreducible minimum. Many ruptured aneurysms don't make it to the hospital," he said. Not all hospitals are sufficiently staffed for an emergency EVAR program. In continental Europe, for example, most hospitals still have more traditional operating vascular surgeons than endovascular specialists.

Despite these good results from the worldwide collected experience, there seems to be confusion about the benefit of emergency EVAR, as well as doubts over the necessity of a large-scale trial to assess the validity of EVAR for ruptured abdominal aortic aneurysms and thoracic aneurysms.

A recent prospective study conducted by Dr. Jean-Pierre Becquemin and his colleagues showed that 61% of patients were anatomically suitable for EVAR, with a 30-day mortality of 23.5%.

The conclusion drawn from the worldwide experience reflects selective use of endovascular grafts for ruptured thoracic and abdominal aortic aneurysms. The 18% mortality and successful treatment of patients otherwise inoperable by standard surgical techniques suggest that EVGs, when feasible, may provide better treatment outcomes than surgery.

"I think the data from the global registry show that the procedure is more effective than an operation," Dr. Veith said in an interview."