Flow-diverter treatment for renal artery aneurysms: One-year follow-up of a multicentric preliminary experience

PURPOSE: Renal artery aneurysms (RAAs) are rare in the general population, although the true incidence and natural history remain elusive. Conventional endovascular therapies such as coil embolization or covered stent graft may cause side branches occlusion, leading to organ infarction. Flow diverters (FDs) have been first designed to treat cerebrovascular aneurysms, but their use may be useful to treat complex RAAs presenting side branches arising from the aneurysmal sac. We aimed to evaluate the mid-term follow-up (FUP) safety and efficacy of FDs during the treatment of complex RAAs. METHODS: Between November 2019 and April 2020, 7 RAAs were identified in 7 patients (4 men, 3 women; age range 55-82 years; median 67 years) and treated by FDs. Procedural details, complications, morbidity and mortality, aneurysm occlusion, and segmental artery patency were retrospectively reviewed. Twelve months of computed tomography angiography (CTA) FUP was evaluated for all cases. RESULTS: Deployment of FDs was successful in all cases. One intraprocedural technical complication was encountered with one FD felt down into aneurism sac which requiring additional telescopic stenting. One case at 3 months CTA FUP presented the same complication, requiring the same rescue technique. At 12 months CTA FUP, 5 cases of size shrinkage and 2 cases of stable size were documented. No rescue surgery or major intraprocedural or mid-term FUP complication was seen. CONCLUSION: Complex RAAs with 2 or more side branches can be safely treated by FD. FD efficacy for RAA needs further validation at long-term FUP by additional large prospective studies.