Comparing Scaffold Design and Recellularization Techniques for Development of Tissue Engineered Heart Valves

Valvular heart disease continues to afflict millions of people around the world. In many cases, the only corrective treatment for valvular heart disease is valve replacement. Valve replacement options are currently limited, and the most common constructs utilized are xenogenic tissue heart valves. The main limitation with the use of this valve type is the development of valve deterioration. Emerging evidence suggests that the underlying driver of valve deterioration is a chronic immune-mediated rejection process of the foreign xenogenic-derived tissue. There is an ongoing focus on the development of an immunologically acceptable, unfixed xenogeneic scaffold for future heart valve constructs. Tissue engineering heart valves are a promising method of developing a durable, non-immunogenic, non-thrombotic, easily implantable, and readily available implant. In this review, we summarize the various decellularization protocols and scaffold designs for tissue engineered heart valve use and highlight the different cell types and methods for recellularization of tissue engineered heart valves. Valve replacement surgery is one of the most common procedures performed by cardiac surgeons. Most patients undergoing valve replacement surgery receive a tissue valve. Tissue valves are made from either cow or pig tissue, and unfortunately tend to fail over time requiring reoperation. One reason these valves fail may be due to a slow rejection of the animal tissue by the human immune system. There is an ongoing focus on the development of artificial heart valves using various tissue engineered designs. The purpose of this review is to summarize various designs and techniques for the creation of artificial heart valves.