title: Anticalcification treatments of bioprosthetic heart valves: in vivo studies in sheep.
abstract: Studies performed by other investigators have shown that a number of preimplantation processes inhibit the calcification of pieces of porcine aortic valves and of bovine parietal pericardium subcutaneously implanted in rats. To evaluate biological reactivity with these biomaterials functioning in an intracardiac position, mitral and tricuspid valve replacements were performed in young sheep to assess the effects of the following preimplantation processes: (1) surfactants, including sodium dodecyl sulfate, polysorbate-80, Triton X-100 and N-lauryl sarcosine; (2) covalently bound aminohydroxypropane diphosphonic acid; (3) toluidine blue; and (4) incorporation of polyacrylamide into valvular tissues. Quantitative calcium analyses showed that only the surfactants substantially reduced calcification, and only in porcine aortic valvular bioprostheses. However, morphological studies showed that some of these agents also induced alterations that decreased the durability of the valves. Toluidine blue decreased calcification to a degree that was statistically significant, but not biologically important. Polyacrylamide incorporation and diphosphonate binding increased calcification. Thus, data regarding anticalcification treatments obtained from subcutaneous implantation studies in small animal models should be cautiously interpreted and validated by studies with intracardiac valvular implantation in large animals.
authors.affiliation: Surgery Branches, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892.
authors.forename: M
authors.initials: M
authors.lastname: Jones
authors.forename: E E
authors.initials: EE
authors.lastname: Eidbo
authors.forename: S L
authors.initials: SL
authors.lastname: Hilbert
authors.forename: V J
authors.initials: VJ
authors.lastname: Ferrans
authors.forename: R E
authors.initials: RE
authors.lastname: Clark
mesh_terms: D000180:Acrylic Resins / Q000494:pharmacology; D000818:Animals; D001672:Biocompatible Materials; D001705:Bioprosthesis; D002114:Calcinosis / Q000517:prevention & control*; D004164:Diphosphonates / Q000494:pharmacology; D006350:Heart Valve Prosthesis; D008943:Mitral Valve; D000077268:Pamidronate; D011474:Prosthesis Design; D012756:Sheep; D013501:Surface-Active Agents / Q000494:pharmacology; D014048:Tolonium Chloride / Q000494:pharmacology; D014261:Tricuspid Valve; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D001672:Biocompatible Materials; D004164:Diphosphonates; D000077268:Pamidronate; D013501:Surface-Active Agents; D014048:Tolonium Chloride; D000099166:Polyacrylamides