Antimineralization Treatments in Stentless Porcine Bioprostheses: An Experimental Study
Willem Flameng MD, Shigeyuki Ozaki MD, Bart Meuris MD, Paul Herijgers MD, Jessa Yperman, Alfons Van Lommel PhD, Erik Verbeken MD

Three types of stentless porcine bioprosthesis (Photofix, Freestyle and Prima Plus) were implanted into the pulmonary artery of 18 juvenile sheep. Calcification characteristics and tissue degeneration were studied after three and six months implantation. With regard to the cusps, all three valve types showed similar results, with good cuspal preservation, low cuspal calcification and low incidence of fibrous tissue overgrowth or cusp retraction. There was no significant difference between cuspal calcium content in the valve types. Important differences were noted regarding the aortic wall portion, however. The two glutaraldehyde-fixed valves (Freestyle and Prima Plus) showed severe aortic wall calcification after only three months implantation, but the wall of Photofix valves showed no major calcific deposit and had significantly lower calcium content than the two other valve types. Photo-oxidation of a porcine stentless valve appears to prevent calcification, not only in the cusps but also in the aortic wall portion.