The treatment of challenging visceral and peripheral arterial aneurysms with flow diversion : a German multicentric observational study

Abstract

Purpose:

Endovascular treatment of visceral and peripheral aneurysms has become the modality of choice over the past few decades. A variety of different techniques are being applied, including deconstructive approaches, such as parent vessel occlusion with coils or liquid embolic agents, and reconstructive approaches, such as stent grafting, stent-assisted coiling, or balloon-assisted coiling. Reconstruction is preferred over vessel or segmental sacrifice due to the risk of ischemia in the dependent territory. However, conventional reconstructive techniques fail, possibly due to the tortuosity of the parent artery or involvement of arterial bifurcations. Flow diversion, a comparatively novel method using densely braided stents, has become well established as a therapeutic option for the treatment of uncoilable or failed aneurysms in cerebral circulation because flow diverter stents can be implanted in highly tortuous vessels and can also be used to treat bifurcation aneurysms without causing occlusion of non-collateralized side branches under sufficient inhibition of platelet function. A few reports have been published on the use of flow diverter stents for the treatment of aneurysms in visceral or peripheral circulation, but systematic studies are lacking. The purpose of this multicenter study is to summarize the experience of different vascular centers that have utilized flow diversion techniques in peripheral vasculature.

Materials and methods:

This multicentric retrospective analysis includes data from 10 vascular centers on treatments performed between 2022 and 2025. Aside from the safety and feasibility of the approach, procedural aspects, antiplatelet medication, follow-up results, and complications were investigated in a retrospective manner.

Results:

A total of 36 patients (22 female, with a mean age of 59.2 years, ranging between 36 and 80 years), one with two aneurysms, were treated in the following arterial territories with decreasing frequency: splenic artery (n = 18), hepatic arteries (n = 8), renal artery (n = 7), superior mesenteric artery (n = 1), gastroduodenal artery (n = 1), external iliac artery (n = 1), and inferior genicular artery (n = 1). From a technical perspective, all treatments were performed successfully. A total of four aneurysms (11%) were occluded immediately at the end of the procedure, while in 33 aneurysms (89%), the perfusion was reduced to a varying extent. At the first follow-up study scheduled after 3 months, 17 aneurysms (46%) were occluded, 14 (38%) showed reduced perfusion, and the remaining six patients had not yet undergone follow-up. At 12 months following the procedure, 26 patients with lesions underwent follow-up. A total of 27 aneurysms (73%) were occluded after 12 months, with 17 of them already examined at the 3-month study, two of those without a follow-up at 3 months and one exhibiting a small neck remnant. At this point, 11 patients with aneurysms had not yet attended the second follow-up study. Complications occurred in two patients (5%); one was related to clopidogrel resistance and manifested as stent occlusion during the intervention, while the other was related to paused antiplatelet therapy due to hemorrhage unrelated to the treated aneurysm and manifested with stent occlusion during the early postinterventional period. Both patients recovered well. Antiplatelet medication differed substantially between the centers.

Conclusion:

Our multicenter observational study demonstrated the excellent safety and efficacy of flow diversion as an alternative treatment modality for visceral and peripheral aneurysms. The complication rates were low, and all complications were related to insufficient inhibition of platelet function during the intervention or in the early postinterventional phase, which can be addressed by platelet function testing prior to the interventions, followed by tailored antiplatelet therapy.