Calcification of valved aortic allografts in rats: Effects of age, crosslinking, and inhibitors

Abstract

Experiments were carried out to investigate rat aortic allograft calcification using valved abdominal aortic allografts. Results indicated that this was a potentially useful model for investigating fresh allograft calcification, as well as mineralization of glutaraldehyde-crosslinked valved allografts. Valve cusp results, however, were not comparable to those noted in large animal or human studies, while aortic wall calcification was more comparable. Calcification inhibitor investigations demonstrated that nearly complete inhibition of the calcification of the aortic wall of glutaraldehyde-crosslinked allografts was achieved using a number of individual inhibitors, including controlled release diphosphonates, and pretreatment with either ferric chloride or aluminum chloride. However, aminopropanehydroxydiphosphonate pretreatment was not efficacious, and sodium dodecyl sulfate pretreatment was only partially effective for inhibiting the aortic wall calcification in the glutaraldehyde-crosslinked allografts. It is concluded that valved aortic allografts in rats provide a useful model for investigating aortic wall (but not valve cusp) calcification and its inhibition.

In vivo behavior of epoxy-crosslinked porcine heart valve cusps and walls

“…This would indicate that crosslinking is not important, but contradicts other reports, which stated that GA-crosslinked valves calcify to a larger extent, compared to nonfixed tissue. 31,32 However, nonfixed tissue in those reports is not exactly the same as IPA-treated tissue. It is not clear whether IPA-cusps were degenerated by calcification.…”

Osteopontin

“…87,100 -103 Because of its beneficial anticalcific affects and ability to promote mineral resorption, OPN is currently being considered as a potential local therapeutic to limit or remove pathological mineralization in cardiovascular settings such as native valve repair and bioprosthetic valve material development. 104,105 …”

Dimethyl 3,3?-dithiobispropionimidate: A novel crosslinking reagent for collagen

“…However, toxicity and long-term calcification are major drawbacks of collagen crosslinked with GTA. [9][10][11] Several reagents have been tried as alternatives for crosslinking of collagen. 12,13 We evaluated the use of dimethyl suberimidate (DMS), a diimidoester, comparing it with GTA as a crosslinking agent for collagen.…”