Endovascular repair of abdominal aortic aneurysms led to lower perioperative mortality than open surgical repair in a large randomized trial, as expected.
However, unlike in earlier studies, this early advantage was not offset by higher rates of late morbidity and mortality during 2 years of follow-up (JAMA 2009;302:1535-42). Two previous European studies showed that reintervention was more frequent with the endovascular approach, so that the early survival advantage it conferred was lost within 2 years of follow-up, said Dr. Frank A. Lederle and his associates in the Open Versus Endovascular Repair (OVER) study group.
The OVER study was undertaken because surgical techniques and devices have improved since the European trials were reported.
Dr. Lederle and his colleagues are performing an ongoing study comparing endovascular against open AAA repair, with the primary outcome of long-term all-cause mortality to be determined in 2011. The current report presents the interim results after 2 years of follow-up.
The 881 patients, aged 49 and older, were treated electively at 42 medical centers by 109 experienced vascular surgeons. A total of 444 patients were randomly assigned to endovascular repair in which an expandable graft system was introduced transluminally. The other 437 patients were assigned to open repair in which a vascular graft was placed anatomically via an abdominal or retroperitoneal incision. Eligible patients had a maximum external AAA diameter of at least 5.0 cm, an associated iliac aneurysm with a maximum diameter of at least 3.0 cm, or a maximum AAA diameter of 4.5 cm plus either rapid enlargement or sacular morphology.
The study subjects were followed in person at 1, 6, and 12 months, and yearly thereafter. They also were followed by phone every month for the first 14 months after the procedure, then annually between study visits, said Dr. Lederle of the Veterans Affairs Medical Center, Minneapolis, and his associates.
Endovascular repair required significantly less procedure time, duration of mechanical ventilation, ICU stay, and hospital stay, and it resulted in less blood loss and fewer transfusion requirements. However, it required substantial exposure to fluoroscopy.
Perioperative mortality was significantly higher with open repair (2.3%) than with endovascular repair (0.2%), as expected. However, unlike in previous studies, all-cause mortality did not increase to a greater degree with endovascular repair over time. There was no significant difference in all-cause mortality between open repair (9.8%) and endovascular repair (7.0%) at 2 years, the investigators said.
There also were no significant differences in procedure failure rates, the need for secondary procedures, aneurysm-related hospitalizations, or major morbidity. These findings remained consistent regardless of patient age and surgical risk status, the diameter of the aneurysm, the presence or absence of coronary artery disease, and the type of graft device used.
In addition, there were no significant differences between the two groups in health-related quality of life or in erectile function. “Erectile dysfunction has been reported to be reduced after endovascular repair compared with open repair, but these data are from nonrandomized retrospective surveys and are subject to recall and response bias,” Dr. Lederle and his associates said.
However, all four late deaths that were related to aneurysm in this study occurred in the endovascular group, they noted.
“Longer-term studies are needed to fully assess the relative merits of the two procedures,” the researchers said.
This study was supported by the U.S. Department of Veterans Affairs. Dr. Lederle reported no financial conflicts of interest. Several of his colleagues reported receiving funding from stent manufacturers.
'Longer-term studies are needed to fully assess the relative merits of the two procedures.'
Source DR. LEDERLE