Investigation of 3D Printed Bioresorbable Vascular Scaffold Crimping Behavior

The rise in additive manufacturing (AM) offers myriad opportunities for 3D printed polymeric vascular scaffolds, such as customization and on-the-spot manufacturing, in vivo biodegradation, incorporation of drugs to prevent restenosis, and visibility under X-ray. To maximize these benefits, informed scaffold design is critical. Polymeric bioresorbable vascular scaffolds (BVS) must undergo significant deformation prior to implantation in a diameter-reduction process known as crimping that enables minimally invasive surgery. Understanding the behavior of vascular scaffolds in this step provides twofold benefits: first, it ensures the BVS is able to accommodate stresses occurring during this process to prevent failure, and further, it provides information on the radial strength of the BVS, a key metric to understanding its post-implant performance in the artery. To capitalize on the fast manufacturing speed AM provides, a low time cost solution for understanding scaffold performance during this step is necessary. Through simulation of the BVS crimping process in ABAQUS using experimentally obtained bulk material properties, a qualitative analysis tool is developed that is capable of accurately comparing relative performance trends of varying BVS designs during crimping in a fraction of the time of experimental testing, thereby assisting in the integration of informed design into the additive manufacturing process. Additive manufacturing advances allow for custom, 3D printed vascular scaffolds with features like biodegradation and drug delivery. Informed design is essential for leveraging these advantages, particularly for the crimping process, which involves significant plastic deformation. A tool is developed for rapidly predicting relative design performance of varying scaffolds during crimping, giving qualitative information beyond what is experimentally accessible. image