Kangaroo versus porcine aortic valve tissue - Valve geometry morphology, tensile strength and calcification potential

Objective. Valve related factors and patient related factors are responsibl e for calcification of valvular bioprostheses. Recent studies showed differ ent donor and recipient species have different influences on the total calc ification rate of bioprostheses, This study was performed to evaluate and c ompare Kangaroo aortic valve leaflets with porcine aortic valve leaflets, E xperimental design. Prospective study. Setting, Cardio-thoracic experimenta l research of a university department. Materials and methods. Glutaraldehyde-fixed Kangaroo and porcine valve leaf lets were evaluated in vitro according to valve geometry (internal diameter and leaflet thickness), morphology (Light and electron microscopy) and ten sile strength. In vivo evaluation consisted of implantation in a rat model for 8 weeks, Von Kossa stain for calcium and atomic absorption spectrophoto metry for total extractable calcium content. Results. Kangaroo valves indicated a smaller internal valve diameter as cc ell as a thinner valve leaflet (p < 0.01, ANOVA) at corresponding body weig ht, less proteoglycan spicules in the fibrosa, increased elasticity (p < 0. 05) and low calcification potential (p < 0.01, confidence interval 95%) Conclusions. Kangaroo aortic valve leaflets have different valvular qualiti es compared to porcine valve tissue. Kangaroo valve leaflets are significan tly superior to porcine valve leaflets as far as calcification is concerned . These results are encouraging and suggest further in vivo evaluation in a larger animal model before clinical application can be considered.