Abnormal vein geometry and pathologic blood flowrates in dialysis patients create complex hemodynamics and loss of dialysis access

Over 750,000 people in the United States receive hemodialysis to treat end-stage renal disease annually, which requires an arteriovenous fistula (AVF). However, AVF maturation and use can result in dysfunctional vein remodeling, stenosis and thrombosis in the cephalic arch (CA) downstream to the AVF, causing access loss. We present a novel method for device fabrication and imaging that recreate complex hemodynamics in large blood vessels at high flowrates in vitro. Briefly, we reconstructed patient-specific 3D models of the CA from venogram, ultrasound and Doppler imaging and fabricated fluidic models of each patient’s CA using 3D printing and soft lithography. We then perfused these models with a fluid that match the density and viscosity of blood at flowrates measured in the patients. Fluorescent tracers in the fluid were imaged in the models at different flowrates, ranging from physiologic to pathologic. We noted laminar flow at physiologic flowrates in all models and complex flow behaviors at pathologic values. We identified distinct flow patterns in the patient models at pathologic flowrates: flow perpendicular to the vessel wall; vortex formation along indentations in the wall; disordered, turbulent flow.