The Impact of Operator’s Learning Curve on the Outcomes of an Off-the-Shelf Multi-Branched Endograft for Complex and Thoracoabdominal Aneurysms Repair

Objectives: The study objectives are to evaluate the impact of the operator’s learning curve on the outcomes of off-the-shelf branched endovascular aortic repair (OTS-BEVAR) in complex and thoracoabdominal (C/TAAAs) aneurysms. Methods: Patients who underwent OTS-BEVAR (T-Branch, Cook-Medical) between 2013 and 2023 were considered. The first and last 25 cases with at least 1 year of follow-up were clustered in two groups (early experience: E.Exp.; late experience: L.Exp.) and compared. Technical success (TS), intraoperative target visceral vessel (TVV) loss, spinal cord ischemia (SCI), 30-day mortality, and TVV instability at 1 year were assessed as primary outcomes. Procedure/fluoroscopy time, iodinated contrast media (ICM) amount and length of hospitalization were assessed as secondary outcomes. A p value < 0.05 was considered statistically significant. Results: Overall, 106 cases were analyzed. Technical success was higher in L.Exp. than E.Exp. (L.Exp.: 25/25 vs. E.Exp.: 17/25; p: 0.004). Moreover, intraoperative TVVs loss was higher in E.Exp. than L.Exp. (E.Exp.: 12/25 vs. L.Exp.: 0/25; p: 0.0001). There were no differences in terms of 30-day/in-hospital mortality (E.Exp.:4/25 vs. L.Exp.:4/25; p: 1), SCI (E.Exp.:2/25 vs. L.Exp.:1/25; p: 1), and paraplegia (E.Exp.: 2/25 vs. L.Exp.: 0/25; p: 0.48) between E.Exp. and L.Exp. Cases of L.Exp. had lower fluoroscopy [E.Exp.: 160(21) vs. L.Exp.:72(18) min; p: 0.003] and overall procedure time [E.Exp.: 518(156) vs. L.Exp.:400(130) min; p: 0.04], ICM [EE: 220(45) vs. L.Exp.: 138(61) mL; p: 0.005] and hospitalization [E.Exp.: 17(9) vs. L.Exp.: 12(4) days; p: 0.03] than cases of E.Exp. Finally, patients managed in L.Exp. had lower TVVs instability at 12 months than patients managed in the E.Exp. (E.Exp.: 8/25 vs. L.Exp.: 1/25; p: 0.04). Conclusions: Cases managed in L.Exp. have higher TS, lower intraoperative TVVs loss and instability at 1-year than cases of E.Exp. Moreover, procedural/fluoroscopy time, ICM, radiation exposure and hospitalization are lower in L.Exp. than E.Exp.