Human placenta as a biological vascular model for endovascular training.

INTRODUCTION: Simulation-based training in endovascular procedures remains limited by the availability of biological vascular models that provide tactile feedback. Existing animal, cadaveric, synthetic, and virtual simulators incompletely reproduce the mechanical behavior of complex neurovascular anatomy. METHODS: Human placentas were prepared by cannulation of the umbilical vessels, vascular flushing, and establishment of continuous gravity-driven flow. Vessel curvature was modified to simulate challenging neurovascular anatomy, including carotid siphon-like configurations, and aneurysm analogues were created. Controlled vessel perforations were performed to simulate emergent hemostatic scenarios. Endovascular procedures included liquid embolization with ethylene-vinyl alcohol copolymer (EVOH) and n-butyl cyanoacrylate (NBCA), coil embolization, flow-diverting stent deployment, and endovascular retrieval techniques. All procedures were performed under angiographic guidance with continuous flow. RESULTS: The placenta model provided reliable angiographic visualization and tactile feedback. Liquid embolization demonstrated procedural behaviors including reflux, plug formation, distal penetration, and effective hemostasis. Stent deployment produced vessel straightening with subsequent elastic recoil. Thrombus and device retrieval simulations demonstrated vessel deformation with recovery after device removal. CONCLUSION: The human placenta represents an ethically favorable biological platform for endovascular training. This model enables simulation of a broad range of neurointerventional and vascular procedures while reducing reliance on animal models.