Associate Professor, Department of Mechanical Engineering and Aeronautics, University of Patras, the Republic of Greece

Speech Title: Cardiovascular implant calcification: An attempt to develop realistic in vitro circulatory model for screening new anticalcification treatments
Abstract: Current biomaterials for replacement of cardiovascular diseases suffer from long term failure due to calcification. Naturally oriented bioprosthetic as well synthetically treated cardiovascular grafts gradually stiffen due to the deposition of calcium phosphate crystals altering their structures and consequently deteriorate their initial good biomechanical performance. Large and small animal models can’t be used for screening anticalcification potential of thousands new biomaterials’ treatments proposed. Especially new generation natural and synthetic biomaterials used as scaffolds in cardiovascular tissue engineering applications have to be investigated in vitro for potential calcification during their limited life span before biodegradation after expected tissue regeneration. In the present work, a novel in vitro model is presented, allowing fast and accurate assessment and comparison of the calcification potential of different bioprosthetic heart valves. Based on previous works done with constant supersaturation systems, a circulatory loop was adapted to simulate physiological and pathological flow conditions for the evaluation of glutaraldehyde fixed porcine and decellularized porcine valves and demonstrating the effect of mechanical loading on the calcification process. The preliminary study of decellularized valves in the circulatory loop showed accelerated calcification of whole aortic roots in comparison with glutaraldehyde treated ones undergoing mild flow conditions.
Keywords: Biomaterials, calcification of bioprostheses, in vitro testing