Structural studies on bovine bioprosthetic tissues and their in vivo calcification: prevention via drug delivery

• Published in: Biomaterials 1996-03, Vol.17 (6), p.577-585
• Main Authors: Chandy, Thomas, Mohanty, Mira, John, Annie, Rao, S.Bhaskara, Sivakumar, R., Sharma, Chandra P., Valiathan, M.S.
• Format: Article
• Language: English
• Subjects: Animals; Biocompatible Materials - metabolism; Biological and medical sciences; Bioprosthesis - adverse effects; Bioprosthesis - standards; bovine pericardium; Calcification; Calcinosis - prevention & control; Calcium Phosphates - metabolism; Cattle; Chitin - analogs & derivatives; Chitin - metabolism; Chitosan; chitosan matrix; Chlorides; Collagen - metabolism; drug delivery; Drug Delivery Systems; Dura Mater - drug effects; Dura Mater - metabolism; Dura Mater - ultrastructure; dura mater and fascialata; Fascia Lata - drug effects; Fascia Lata - metabolism; Fascia Lata - ultrastructure; Ferric Compounds - metabolism; Glutaral - chemistry; Glutaral - pharmacology; Male; Medical sciences; Microscopy, Electron; Microspheres; Myofibrils - metabolism; Pericardium - drug effects; Pericardium - metabolism; Pericardium - ultrastructure; Rats; Rats, Wistar; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Technology. Biomaterials. Equipments
• ISSN: 0142-9612; 1878-5905
• DOI: 10.1016/0142-9612(96)88708-4

Cardiovascular calcification, the formation of calcium phosphate deposits in cardiovascular tissue, is a common end-stage phenomenon affecting a wide variety of bioprostheses. To study the process of calcification in tissue prosthetics, glutaraldehyde-treated bovine pericardium, dura mater and fascialata were implanted subcutaneously in rats and retrieved 21 days later and thereby morphological findings were correlated with biochemically determined levels of calcium. Transmission electron microscopy showed that calcification primarily involved the surface of collagen fibrils and the interfibrillar spaces. The deposition of calcium was higher with dura and fascia prostheses compared to pericardium. However, the release of Fe 3+ ions from chitosan matrix had substantially inhibited the deposits of calcium in all implanted tissues. It seems that the structural and anatomical features of the tissue is one of the important factors for tissue-associated calcification. It is also confirmed that glutaraldehyde-preserved pericardium is the most suitable material for the development of cardiac prosthesis, with an appropriate drug combination therapy for prevention of pathological calcification.