Endovascular vs. open repair of abdominal aortic aneurysms in the Medicare population

Randomized trials have shown reductions in perioperative mortality and morbidity with endovascular repair of abdominal aortic aneurysm, as compared with open surgical repair. Longer-term survival rates, however, were similar for the two procedures. There are currently no long-term, population-based data from the comparison of these strategies.

We studied perioperative rates of death and complications, long-term survival, rupture, and reinterventions after open as compared with endovascular repair of abdominal aortic aneurysm in propensity-score-matched cohorts of Medicare beneficiaries undergoing repair during the 2001-2004 period, with follow-up until 2005.

There were 22,830 matched patients undergoing open repair of abdominal aortic aneurysm in each cohort. The average age of the patients was 76 years, and approximately 20% were women. Perioperative mortality was lower after endovascular repair than after open repair (1.2% vs. 4.8%, P<0.001), and the reduction in mortality increased with age (2.1% difference for those 67 to 69 years old vs. 8.5% for those 85 years or older, P<0.001). Late survival was similar in the two cohorts, although the survival curves did not converge until after 3 years. By 4 years, rupture was more likely in the endovascular-repair cohort than in the open-repair cohort (1.8% vs. 0.5%, P<0.001), as was reintervention related to abdominal aortic aneurysm (9.0% vs. 1.7%, P<0.001), although most reinterventions were minor. In contrast, by 4 years, surgery for laparotomy-related complications was more likely among patients who had undergone open repair (9.7%, vs. 4.1% among those who had undergone endovascular repair; P<0.001), as was hospitalization without surgery for bowel obstruction or abdominal-wall hernia (14.2% vs. 8.1%, P<0.001).

As compared with open repair, endovascular repair of abdominal aortic aneurysm is associated with lower short-term rates of death and complications. The survival advantage is more durable among older patients. Late reinterventions related to abdominal aortic aneurysm are more common after endovascular repair but are balanced by an increase in laparotomy-related reinterventions and hospitalizations after open surgery.