As the size of an abdominal aortic aneurysm increases, so does its risk of rupture. Prophylactic repair with the insertion of a prosthetic graft is typically offered for patients with an abdominal aortic aneurysm of 5 cm or larger. Open surgical repair for such patients has been available since the early 1950s, and the less-invasive endovascular repair was introduced in the mid-1980s, providing an alternate option for some patients. Though it is commonly used today, good data on durability, cost and effects of endovascular repair are lacking. The EVAR trials address whether endovascular repair is better than open repair, and for those patients ineligible for open repair, whether endovascular repair is better than no repair.
The long-term results for EVAR 1 and EVAR 2 are published this week to coincide with a presentation of the results at the Charing Cross International Symposium in London.
In EVAR 1, patients with large abdominal aortic aneurysms were assigned to either endovascular repair or open surgical repair. Operative mortality was lower with endovascular repair, but with a median of 6 years follow up, results showed no long-term mortality advantage for either open repair or endovascular repair. Endovascular repair was associated with more graft-related complications and reinterventions, and was more costly.
Those who were not candidates for open repair, but anatomically suitable for endovascular repair, were invited to participate in EVAR 2. Patients were randomized to either endovascular repair, or no repair. After a median of 3 years, results showed that aneurysm-related mortality was significantly lower with endovascular repair, but there was no difference in all-cause mortality between the two groups.
“There’s no clear winner here,” says NEJM deputy editor, Dr. John Jarcho. “While there was concern that the grafts might not be as durable with endovascular repair, it’s surprising that there wasn’t a long-term survival advantage over no repair.”
EVAR 2 authors note, “Previous studies have suggested that anatomical suitability may impart some protection against rupture.” The rupture rate in the no repair group was somewhat lower than expected.
The authors of EVAR 1 speculate that endovascular repair may also improve with time. They used second- and third-generation allografts in the study, but there are newer iterations of the grafts used today.
“The long-term durability of these later iterations of endografts has not been evaluated, but it is hoped that they would be associated with lower complication rates.”
How would you guide your patient in making a decision about what to do? Will these results increase or reduce the frequency of using endovascular repair?