Currently, custom made heart implants suffer from critical imperfections in terms of mechanical incompatibility and uncontrolled degradation rate, which leads to premature in vivo failure. Interpenetrating polymer networks (IPNs) are a success story in drug delivery and regenerative medicine where they offer fascinating morphologies and tailored properties like controlled degradation rate. This review will critically discuss the current state of the art with respect to the two most important biopolymers found in heart valve, i.e. collagen and hyaluronic acid formulated IPNs as tissue engineered heart valve (TEHV). Comparison of the existing experimental approaches and recent technical challenges will be demonstrated. Finally, multifaceted proposals for improvements in design and performance of TEHVs will be presented as a route map for future research.
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