Design and Fabrication of a Device to Mimic the Motion of the Left Anterior Descending Coronary Artery

摘要

Cardiovascular diseases are the leading cause of death in the world, and one of the most vulnerable sites for these diseases are coronary arteries. The hemodynamics of these arteries are significantly influenced by their complicated dynamic geometry, due to the fact that they are attached to the myocardium. Here we present a new approach for design and fabrication of an in vitro device to mimic a simplified motion of the left anterior descending artery, in order to be able to be used for further studies on the hemodynamics of this artery. The artery is modeled with a flexible Silicone rubber tube of 3.5 mm inner diameter and 47 mm length. The complex motion of the artery is simplified into a solid-body like radial expansion movement while the inlet end is fixed and the outlet end moves with a sine wave at 1 Hz and 1.5 Hz. A 4-bar link mechanism is developed to make the moving end of the tube to move in a desired groove. The rotary motion is provided by a motor and a gearbox. The device includes three planes: the motor, gearbox, and the mechanism are placed on top of the first plane, while the groove is fabricated in the second plane and the tube is placed on top of the second plane. A third plane is provided to place a camera facing the tubing to monitor its motion and deformation. Results showed that the circular cross-section of the tube was remained intact when the tube was experiencing its minimum curvature radius. The minimum and maximum curvature radii provided by this device were measured to be 16.21 mm and 62.57, which are very close to the physiological values of 16 mm and 64 mm. Considering a dynamics angular velocity for the motor and 3D motion of the artery can help to get more realistic results for future works.