Novel concepts in design and fabrication of 'living' bioprosthetic heart valves: From cell mechanosensing to advanced tissue engineering applications

Abstract

Despite the use of bio-valve prostheses to replace diseased heart valves dates more than 50 years ago, and the large and increasing need of this type of implants for heart surgery worldwide, definitive solutions to manufacture 'lifetimelong' valve replacements are not yet available. In fact, although various problems in the manufacturing process of these implants have been circumvented compared with the beginnings, these solutions have not yet led to a full biological compatibility in the human system due to long term inflammation, calcification and ultimately structural valve deterioration. Importantly, the more limited duration of the valve bio-prostheses occur in pediatric patients and adults under the age of 65. These are the patients who more often need prosthesis replacement and therefore new invasive surgical interventions with a compromised quality of life. The present contribution is centred onto the dissection of the valve cells response to mechanical stimuli regulated by the extracellular matrix, and new engineering systems that have been set up to mimic the tissue mechanics in the heart valve leaflets and manufacture the 'living bioprosthetic' valves. This latter goal is being pursued intensely worldwide by exploiting the most advanced technologies in material science and scaffolds design.