A novel approach in cross-linking of bioprosthetic heart valves

Due to some form of heart valve disease, approximately 250000 patients worldwide undergo surgery to receive a new heart-valve each year. In about 70% of the cases a mechanical heart valve is used despite the fact that permanent anticoagulant therapy for the patient is required. The remaining 30% of the patients receive a bioprosthesis, made from porcine or bovine material. Since a porcine heart is similar to a human heart also complete porcine valves can be used. If bovine material is used, the valve leaflets are made from sheets of pericardium. Either bioprostheses which are constructed by mounting valve leaflets on a supporting rig (a stent) or complete stentless porcine valves including leaflets and root (wall) are used. Although the bioprosthetic valve has initially in many ways a superior performance compared to the mechanical valve, the reason why it is currently only employed in such a relatively small patient population is because after several years it is prone to increased incidents of degeneration, calcification and cusp rupture. These phenomena occur especially in young adults. Modern mechanical valves, on the other hand, are durable and have excellent flow characteristics, but have the propensity for thrombo-embolic complications, necessitating life long anticoagulation therapy with the result of increased risk of bleeding. This has triggered the desire to develop a better, i.e. more durable bioprosthesis and many attempts have been described in literature