Fabrication And Characterization Of Novel Composite Scaffolds As Bioprosthetic Heart Valves

The heart valve disease is a common disease worldwide,with the main syptoms of stenosis or regurgitation,resulting in cardiac and pulmonary vascular lesions due to the hemodynamic changes.Valves calcification are the main reason of the failure of valvular functions.The most effective treatment for valvular disease at the end stages is valve replacement,about 275000 cases of each year in the world.The widely used devices for valve replacement include mechanical valves and bioprosthetic heart valves.Mechanical valves require life time medication for anticoagulation,while bioprosthetic heart valves are prone to calcification and progressive degeneration.Thus,development of novel heart valve substitutes with proper hemodynamic and mechanical properties,as well as anti-coagualtion and anti-calcification functions,are of great interest,which is also the major goal of our study.In this study,the porcine heart valves were selected as experimental materials,which were decellularized using sodium dodecyl sulfate(SDS)and Triton X-100,characterization for morphology and mechanical performance,with the resulting of elastic moduli of porcine aortic valve leaflets are 3.772 MPa and decellularized ECM are 3.232 MPa.And preparated poly(ethylene glycol)diacrylate(PEGDA)and SiO2,then used to fabricate novel ECM-PEGDA-SiO2 composite scaffolds as artificial heart valves,using ultraviolet crosslinking followed by chemical crosslinking.The mechanical properties and hydrodynamic and biological functions of these novel composite scaffolds were further studied.Investigation of various properties and function of the novel ECM-PEGDA-SiO2 composite scaffolds,including mechanical properties using uniaxial tension tests,with the elastic moduli are 5.635 MPa,as well as hydrodynamic properties tested by a pulse duplicator,with beat rate of 70 bpm,cardiac output(CO)of 5.0 mL/min,systolic duration of 35%,the cross valve pressure(ΔP)is 7.009±0.41 mmHg,effective orifice area(EOA)is 1.814±0.03 cm2,regurgitant fraction(RF%)is 6.39±0.39%,while systolic duration is 50%,ΔP is 4.695±0.39 mmHg,EOA is 1.904±0.02 cm2,RF%is 6.98±0.43%,meanwhile ΔP and EOA perfectly increased with the CO,according to the ISO 5840 standard.In vitro calcication and enzyme degradation,with the functions for anti-calcification and prevention of enzyme degradation,isolation and culture of endothelial and interstitial cells from porcine aortic valve leaflets,and evaluation of biocompatibility for ECM-PEGDA-SiO2 composite scaffolds by co-culture with valvular interstitial cells.