Aortoiliac fenestrated stent demonstrates superior flow dynamics to kissing iliac stents in a large animal.

OBJECTIVE: Current endovascular treatment of aortoiliac occlusive disease with kissing iliac stents has suboptimal long-term patency and durability secondary to pathologic flow fields. The aortoiliac fenestrated (AIFEN) stent was previously introduced to provide an anatomically preserving endovascular therapy that may improve flow dynamics compared with kissing iliac stents. The aim of this study was to compare flow dynamics between the AIFEN stent and conventional kissing iliac stents in vivo in an adult porcine model. METHODS: AIFEN stents were manufactured via benchtop modification of standard balloon-expandable covered stents. Three adult Yorkshire pigs underwent endovascular AIFEN implantation in the distal aorta with bilateral iliac stents (group 1), whereas three pigs received conventional kissing iliac stents (group 2). Over 4 weeks of survival, patency was assessed using weekly femoral ultrasound. Pre-explant computed tomography angiography with computational flow modeling was used to evaluate arterial flow dynamics, including vorticity and flow rate. RESULTS: All pigs in both groups survived the 4-week study period without complications. Fluoroscopy at implantation and terminal procedures confirmed patent stents in all animals. Serial ultrasound demonstrated patent bilateral femoral artery outflow throughout the study. Computed tomography angiography-based flow dynamic analysis revealed that group 1 had significantly reduced iliac artery vorticity (P = .02) and higher flow rates (P = .004) compared with group 2. CONCLUSIONS: The anatomically designed AIFEN stent demonstrated superior flow dynamics compared with kissing iliac stents in a porcine model. These findings support further development of anatomically preserving balloon-expandable stent designs to improve endovascular treatment of aortoiliac occlusive disease. CLINICAL RELEVANCE: Endovascular treatment of aortoiliac occlusive disease commonly relies on kissing iliac stents; yet, this configuration alters native aortoiliac geometry and can generate disturbed flow patterns that contribute to thrombosis. In this large-animal study, an anatomically preserving aortoiliac fenestrated stent configuration demonstrated significantly improved flow dynamics compared with conventional kissing iliac stents, including reduced vorticity and increased flow rates. By maintaining more physiologic aortoiliac architecture, the aortoiliac fenestrated approach may mitigate adverse hemodynamic conditions associated with current endovascular strategies. These findings support further development of anatomically guided stent designs for the infrarenal aortic bifurcation that are aimed at improving durability and outcomes in patients with aortoiliac occlusive disease.