Renal function alteration after bridging stenting in branched and fenestrated endoprostheses

Objective: The aim of this prospective single-center study was to evaluate the impact of renal artery configurations—branches versus fenestrations—on renal function in the early post-operative period. Methods: Between March 2018 and June 2023, we enrolled 112 patients who underwent elective fenestrated and branched endovascular aneurysm repair (F/BEVAR). Participants were categorized into two groups based on their renal bridging component configuration: fenestrations or branches. All patients underwent dynamic renal scintigraphy with 99mTc diethylenetriaminepentaacetic acid (DTPA) two weeks before surgery, and at three months and one year after the procedure. The primary endpoints included peri-procedural technical success, incidence of major adverse events within 30 days, differences in glomerular filtration rate (GFR) between the two configurations, and variations in pre-operative and post-operative dynamic renal scintigraphy results. Finally, concordance between the scintigraphy findings and the long-term eGFR assessment basing on creatinine level measurement was analyzed. Results: A total of 226 kidneys were analyzed, comprising 126 from the 63 patients with branches and 100 from the 49 patients with fenestrations. The mean baseline GFR was 58.4 ± 18.6 mL/min for the fenestration group and 65.1 ± 19.8 mL/min for the branch group. Only kidneys with a patent fenestration or branch were included in the final analysis of split GFR. The mean total GFR demonstrated a decrease of 6.0 ± 1.2 mL/min in the fenestration group and a reduction of 23.4 ± 6.4 mL/min in the branch group at the three-month follow-up. The split GFR decreased by 3.5 ± 0.6 mL/min for fenestrations, while it declined by 15.4 ± 5.4 mL/min for branches. Notably, the decrease in GFR persisted at one year. Additionally, the scintigraphy results were corroborated at two years, 2 years eGFR was calculated for both groups and demonstrated to be 59.5 ± 22.1 in the fenestrations group and 50.9±11.7 in the branches group. . Conclusion: This study indicates that utilizing branches for renal arteries during F/BEVAR is associated with a more significant decline in GFR compared to patients treated solely with fenestrations. The scintigraphic changes were observed as early as the three-month follow-up, highlighting the impact of configuration on renal function.