Analysis of Repair Type and Hypogastric Artery Antegrade Perfusion and Erectile Function following Repair of Abdominal Aortic Aneurysms

Abstract

Background: Published reports suggest that exclusion of antegrade hypogastric artery flow may have deleterious effects on erectile function after abdominal aortic aneurysm (AAA) repair. Off-label and open surgical hybrid procedures and, more recently, purpose-built branched devices have been developed to maintain antegrade pelvic perfusion in patients undergoing endovascular repair. Maintaining antegrade perfusion may reduce a spectrum of risks, including buttock claudication, colorectal ischemia, and spinal cord ischemia when patients undergo subsequent thoracic aortic procedures, as well as erectile dysfunction (ED). This project specifically focuses on erectile function, and analyzes baseline associations and relationships of hypogastric artery exclusion on changes in erectile function following aneurysm repair.

Methods: Male patients in the Veterans Affairs Open Versus Endovascular Repair (CSP#498; OVER) Trial had erectile function assessed preoperatively and postoperatively by administration of the International Index of Erectile Function-5 questionnaire. Bayesian mixed-effects regression models were created with the outcome variable (erectile function) treated as a latent variable. Primary effects of differences in erectile function between groups with and without preservation of bilateral antegrade hypogastric flow were compared.

Results: 876 men (442 randomized to endovascular repair) were enrolled in the trial and included in the analysis comparing treatment assignment. There is significant ED in elderly men with aortic aneurysm at baseline. Over 5 years of follow-up, there is modest decrease in erectile function and the endovascular group has improved function compared to open repair (0.082; 95% credible interval (CI) 0.008 and 0.155). A fifth of patients did not have bilateral preservation of antegrade hypogastric artery perfusion, with no difference in erectile function by univariate analysis. A more detailed regression analysis was applied--and after adjustment for baseline score, age, beta blocker use, diabetes, activity level, ejection fraction, preoperative ankle-brachial indices and time--preservation of both antegrade hypogastric arteries' perfusion showed transient improvement in survey scores compared to occlusion of at least 1 hypogastric artery at 6 months and 12 months after treatment, although this was not sustained at 60 months (score change: 0.046; 95% CI: -0.123, 0.215). Retesting this model in the cohort with complete data as a sensitivity analysis did not meaningfully change the conclusions.

Conclusions: In this large prospective aneurysm treatment trial with systematic measurement of erectile function with a validated instrument, endovascular repair is associated with improved erectile function. Preservation of antegrade hypogastric flow with any repair is associated with early improved erectile function; however, it is not a sustained benefit. There is limited benefit of maintaining bilateral hypogastric artery perfusion for this specific indication in unselected men undergoing AAA repair.