LAKE BUENA VISTA, FLA. – Endovascular aortic aneurysm repair was associated with improved early all-cause and early abdominal aortic aneurysm–related mortality, compared with open aortic aneurysm repair in a pooled analysis of data from three large randomized trials.
However, EVAR was also associated with a significant increase in late AAA–related mortality.
The overall mortality rate was similar at 28.1% in 1,243 EVAR patients, and 29.6% in 1,241 open repair patients included in the meta-analysis, as was the overall AAA-related mortality (3.5% vs. 4.9%; odds ratio 0.73), Dr. Caron B. Rockman reported at the annual meeting of the Society for Clinical Vascular Surgery.
Dr. Caron Rockman
However, EVAR was associated with about a 70% reduction in both early all-cause mortality (OR 0.27) and early AAA-related mortality (OR 0.36), said Dr. Rockman of New York University Medical Center.
No significant differences were seen between the groups in regard to late all-cause mortality (OR 0.93), but the findings regarding late AAA-related mortality favored open repair; mortality was 2.2% in the EVAR patients, compared with 0.9% in the open repair patients (OR 2.25).
The trials included in the meta-analysis were the Dutch Randomized Endovascular Aneurysm Management (DREAM) trial, the Standard Open Surgery vs. Open Endovascular Repair of AAA (OVER) trial, and the EVAR-1 trial. All three compared various outcomes with EVAR and open repair.
Prior to these trials, EVAR was generally considered the preferred approach for treating AAAs because of its less invasive nature, improved perioperative outcomes (including morbidity, mortality, transfusion requirements, and hospital length of stay), and improved recovery time, but long-term durability remained a matter of controversy, Dr. Rockman explained.
Although the findings of these trials did provide important additional data for the clinician, they also served to continue the debate regarding late outcomes of EVAR, particularly with regard to the issue of higher incidence of late AAA-related mortality, she said.
This meta-analysis of the trials shows that EVAR is clearly better with regard to early all-cause and aneurysm-related mortality, and that the two strategies appear to be equal with regard to late and overall all-cause mortality, cardiovascular mortality, and overall aneurysm-related mortality, while open repair is better in regard to graft-related complications, the need for secondary interventions, and late aneurysm-related mortality, she said.
Two of the trials specifically looked at graft-related complications, and both showed significant benefit with open repair. The pooled data also showed a significant benefit with open repair (OR 6.1), she explained.
In terms of secondary interventions, each of the three trials showed an increase in the EVAR patients, which reached statistical significance in two of the three. In the pooled analysis, EVAR was associated with a twofold increase in the risk of a secondary procedure, Dr. Rockman noted.
As for late mortality, however, she said: "I think we have to remember that the goal of EVAR is to prevent aneurysm rupture–related death – not to provide immortality; late mortality will always equalize in the end," she said.
That is, the longer the follow-up, the more one would expect all-cause mortality to equalize.
"In EVAR-1, when you look at aneurysm mortality, it was essentially equal in both groups, in fairness," she said.
The findings raise some questions, however, and underscore the inherent limitations of any meta-analysis.
For example, the trials used varying definitions of early and late complications, device failures, and secondary interventions, and it is unclear whether the trials represent contemporary devices and practices. They began enrolling patients as early 1999, and it is arguable that things have changed since then, she noted.
Also, there are questions about when secondary interventions are required.
"It’s very easy to say that EVAR has more secondary interventions, but a lot of these interventions, for example, are being done for type 2 endoleaks, and some of us might believe that these interventions are not, in fact, necessary," she said.
"And finally, with regard to secondary interventions, is a hernia repair equivalent to an intervention for a type 1 endoleak? I don’t have a perfect answer for that," she added.
Thus, based on the available evidence, she concluded that "although the success of EVAR in reducing late AAA-related mortality might be suboptimal, the importance of decreased early mortality cannot be minimized, particularly from the patient’s perspective ...EVAR remains the procedure of choice in anatomically suitable aneurysm patients."
Future research should focus on improvements in design and techniques that will decrease device-related complications, reduce the need for secondary interventions, and improve long-term success with EVAR, she added.
Dr. Rockman had no disclosures.