Study Validates SVS Volume Recommendations for Open AAA Repair

February 10, 2022—The Society for Vascular Surgery announced the publication of a multicenter, retrospective database analysis that suggests improved open abdominal aortic aneurysm (AAA) outcomes when surgeon volume is greater than seven cases yearly and performed in hospitals with a 30-day mortality rate < 5%.

The study, which was led by Adam Doyle, MD, from the University of Rochester Medical Center in Rochester, New York was published by Joshua T. Geiger, BS, et al in the Journal of Vascular Surgery (2022;75:504-513).

The context of the study is that SVS published updated practice guidelines in 2018 that recommended open AAA repair be limited to centers that meet a case volume threshold and outcome target of ≥ 10 open repairs per year and a 5% mortality rate.

According to SVS, Dr. Doyle and colleagues utilized the Statewide Planning and Research Cooperative System (SPARCS) managed by the New York Department of Health to determine mortality and morbidity after open AAA repair between the two groups.

The investigators queried records from 2000-2014. The study was composed of 7,594 patients treated by 542 surgeons at 137 hospitals during that 12-year period. The annual open AAA repair case volume averaged 12.9 (median, seven) for the hospitals, and five (median, three) for the surgeons.

The investigators reported that 4,000 cases were performed in centers meeting the SVS criteria versus 3,594 cases performed in centers that did not. Comparing outcomes between the groups, the researchers noted significant differences in centers meeting criteria versus those not meeting criteria in 1-year mortality (9.2% vs 13.6%; P < .001) and 30-day mortality (3.5% vs 6.9%; P < .001). Of note, complication rates between the groups were similar except for the rate of pulmonary complications, which was significantly lower in centers meeting the SVS criteria.

“Open AAA repair has decreased in frequency owing to the increasing adoption of endovascular techniques, prompting concern that the decreased yearly clinical experience will affect operative results,” commented Dr. Doyle in the SVS press release.

“In the present study, we used a pragmatic approach to gauge the effect of the SVS guidelines by analyzing two groups—one that met the recommendations versus one that did not. We then tried to determine if surgeon versus hospital volume was more important for good outcomes.

“In the present study, we attempted to bring previous theoretical volume-outcome work into the practical sphere by directly evaluating current guidelines. These data showed a positive correlation between the 2018 SVS AAA guidelines and outcomes for elective open AAA repair within the SPARCS data set. Further, whether the surgeon volume or hospital volume better predicts outcomes has been disputed. Our analysis suggests the superior outcomes are achieved by surgeons who perform greater than seven open AAA cases yearly and by centers with an established open AAA 30-day mortality rate of < 5%.”

Dr. Doyle concluded, “This supports centralizing elective open AAA operations to higher-volume surgeons at high-quality centers. This may have educational value for trainees as high-volume surgeons tend to practice at teaching hospitals.”

The Journal of Vascular Surgery editors advised that this important study supports the SVS guidelines for open AAA repair and provides guidance for patients who have the opportunity to choose where and by whom their aneurysm is to be fixed, stated the SVS press release.