Development of 3D‑printed coronary artery model with motion simulation

Patient-specific 3D-printed vascular models provide an excellent alternative to in vivo animal models for benchtop testing and validation of new imaging and medical device technologies for the treatment of vascular diseases. 3D printed coronary artery models, can replicate vascular structures with a high degree of accuracy but fail to reproduce the physiologic motion, limiting their utility in preclinical testing. In this work, we present the design of coronary artery models that mimic the motion induced by the beating heart. A coronary artery model derived from a patient CT scan was segmented and converted into a printable 3D model using Meshmixer and SolidWorks. The coronary arteries were mounted on a flexible, hollow balloon structure with an inlet and outlet for fluid/air circulation. The phantom was fabricated using Stratasys J750 Digital Anatomy 3D-printer, with Agilus30 materials selected for their tissue-like properties. Coronary motion was simulated by cyclically inflating and deflating the balloon with air via a syringe controlled by a programmable linear actuator, simulating phases of the cardiac cycle. X-ray images were acquired with the Infinix Biplane Angiography Imaging System (Canon Medical Systems) under simulated motion, both with a catheter/wire placed within the coronary arteries and with contrast-filled coronary vessels. From these images, the balloon expansion was measured to be 3.826mm, corresponding to a 10.35% increase in diameter during inflation. The resulting coronary artery displacement, estimated by tracking catheter tip as reference point, was approximately 6.575mm over 600ms interval. This work demonstrates a method for integrating motion simulation into a 3D-printed coronary artery phantom. These models can be further adapted to represent various cardiovascular diseases, such as stenosis. These models can serve as platforms for in vitro flow experiments to validate new imaging technologies such as 1000 fps High-Speed-Angiography for assessing the severity of stenosis on coronary flow.