When Anatomy Matters Most: A Multicentre Evaluation of Strategies for Renal Artery Aneurysm Repair

Renal artery aneurysms (RAAs) are rare lesions with debated indications and treatment strategies. Endovascular techniques (ET) have expanded, whereas open surgery (OS) remains preferred for complex anatomies requiring branch reconstruction. This study aimed to describe and evaluate the surgical and endovascular management of RAAs.

A retrospective, multicentre study of 141 patients (149 interventions) across six French centres (2007 - 2023) was conducted. Treatment was selected according to anatomy, branch involvement, and operator expertise. The primary endpoint was 1 year composite success, defined as treated artery patency with preserved renal function. Secondary outcomes were post-operative complications, re-intervention, and renal function at 1 year. Factors associated with failure were analysed using univariable tests and multivariable mixed effects logistic regression.

OS accounted for 71.8% of interventions. One year composite success was 86.6%. Ex vivo reconstructions (21.5% of OS) achieved 95.7% success, despite more complex anatomy. ET reached 85.7% success and had fewer peri-operative complications. Complications occurred in 18 interventions (12.1%): 15 after OS (seven haematomas, six thromboses, and two wound dehiscences) and three after ET (one thrombosis, two retroperitoneal haematomas). Re-interventions occurred in 7.4%, and 1 year mortality was 4.3%. Renal function remained stable (mean estimated glomerular filtration rate 83.5 vs. 89.3 mL/min/1.73m²). Greater distance between the renal ostium and first collateral increased success, whereas more than two efferent arteries and post-operative vascular complications predicted failure.

Both OS and ET achieved high success and preserved renal function when anatomically tailored. OS remains preferred for complex hilar lesions, whereas ET is safe in selected cases. Anatomical complexity and peri-operative complications were the main determinants of outcome.