Retroperitoneal versus Transperitoneal Approach for Open Repair of Complex Abdominal Aortic Aneurysms

No difference in midterm outcomes and complication rate between retroperitoneal and transperitoneal open aortic aneurysm repair in females

ObjectivesAbdominal Aortic Aneurysms (AAA) in females are less prevalent, have higher expansion rates and experience rupture at smaller diameters than in males. Studies have compared outcomes of the retroperitoneal (RP) and transperitoneal (TP) approach in open aortic aneurysm repair (OAR) with conflicting results. No study to date has compared the two approaches solely in females. In this study we compare midterm outcomes of the RP and TP approach in females undergoing OAR.MethodsSingle-center, retrospective review of all females undergoing OAR from 2010 to 2021. Patients undergoing elective, symptomatic and ruptured OAR were included. The cohort was stratified by surgical approach RP versus TP and midterm outcomes were compared amongst the groups. Outcomes included mortality, graft related, and non-graft related complications.ResultsA total of 244 patients (RP n = 133; TP n = 111) were identified. Follow-up period was 28 ± 30.7 months. Baseline perioperative characteristics were similar except that more people in the RP group had ejection fraction ((EF) > 50% (82% vs 68%), p = .037). Patients who underwent RP repair had longer visceral/renal ischemia time (p = .01), larger graft diameter (18 vs 16 mm; p = <0.001), were more likely to have a suprarenal clamp placed(70.5 vs 48.2; p < .001), and had decreased autotransfusion volume (611 vs 861 mL; p < .01) compared to those who underwent TP repair. Number of deaths was higher in the TP group during study follow-up period (36.4 vs 23.8; p = .035), but the difference of the time to event analysis was not significant. There was no difference in all-cause survival at 36 months between RP and TP (77.8 vs 76.8; p = .045). Overall midterm complications were 9.5% in both groups. Any graft related complication was 1.8% in TP versus 3% RP (p = .69). In a multivariable model, after adjusting for age, urgency, smoking, prior aneurysm repair, and ASA level, the hazard ratio decreases with the RP approach, however this did not reach significance (p = .052).ConclusionIn a 12-year period of OAR in females, TP and RP results were comparable at midterm analysis. The RP approach appeared to be used more often for OAR requiring suprarenal clamping. Although the TP group had increased mortality, the difference of the time to event analysis was not significant. Midterm postoperative complications in both groups were low. This suggests that both approaches are safe in the female population and decision should be driven by anatomy and surgeon's preference.

Retroperitoneal vs transperitoneal approach for nonruptured open conversion after endovascular aneurysm repair

OBJECTIVE

Several studies comparing the transperitoneal (TP) and retroperitoneal (RP) approach for abdominal aortic aneurysm (AAA) repair suggest that the RP approach may result in lower rates of perioperative mortality and morbidity. However, data comparing these approaches for open conversion are lacking. This study aims to evaluate the association between the type of approach and outcomes following open conversion after endovascular aneurysm repair (EVAR).

METHODS

We included all patients who underwent open conversion after EVAR between 2010 and 2022 in the Vascular Quality Initiative. Patients presenting with rupture were excluded. The primary outcome was perioperative mortality. The secondary outcomes included perioperative complications and 5-year mortality. Inverse probability weighting was used to adjust for factors with statistical or clinical significance. Logistic regression was used to assess perioperative mortality and complications in the weighted cohort. The 5-year mortality was evaluated using Kaplan-Meier and Cox regression.

RESULTS

We identified 660 patients (39% RP) who underwent open conversion after EVAR. Compared with TP, RP patients were older (75 years [interquartile range, 70-79 years] vs 73.5 years [interquartile range, 68-79 years]; P < .001), and more frequently had prior myocardial infarction (33% vs 22%; P = .002). Compared with the TP approach, the RP approach was used less frequently in cases of associated iliac aneurysm (19% vs 27%; P = .026), but more frequently with associated renal bypass (7.8% vs 1.7%; P < .001) and by high-volume physicians (highest quintile, >7 AAA annually: 41% vs 17%; P < .001) and in high-volume centers (highest quintile, >35 AAA annually: 36% vs 20%; P < .001). RP patients, compared with TP patients, were less likely to have external iliac or femoral distal anastomosis (8.2% vs 21%; P < .001), and an infrarenal clamp (25% vs 36%; P < .001). Unadjusted perioperative mortality was not significantly different between approaches (RP vs TP: 3.8% vs 7.5%; P = .077). After risk adjustment, RP patients had similar odds of perioperative mortality (adjusted odds ratio [aOR], 0.49; 95% confidence interval [CI], 0.22-1.10; P = .082), and lower odds of intestinal ischemia (aOR, 0.26; 95% CI, 0.08-0.86; P = .028) and in-hospital reintervention (aOR, 0.43; 95% CI, 0.22-0.85; P = .015). No significant differences were found in the other perioperative complications or 5-year mortality (aHR, 0.79; 95% CI, 0.47-1.32; P = .37).

CONCLUSIONS

Our findings suggest that the RP approach may be associated with a lower adjusted odds of perioperative complications compared with the TP approach. The RP approach should be considered for open conversion after EVAR when feasible.