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

Lyophilized glutaraldehyde-preserved bovine pericardium for experimental atrial septal defect closure

“…In contrast with Dacron, which is a synthetic material, it is not subjected to contraction during the wound healing process, and it is not used as scaffold. The shrinkage of a patch is of little or no importance in closure of simple defects -like ASDthat lie in a single plane (Crawford et al, 1986). We wonder if with longer study time in LGPBP group we could find a completed closed ASD area with own's patient atrial tissue, from the hypothesis that LGPBP can be used as scaffold for atrium tissue growth or migration.…”

“…Many studies have been published in order to understand, to prevent or to treat the degenerative process (Franks, 1998;Chandy et al, 1996;Golomb, 1987). Lyophilization has been used to decrease aldehyde residues in GPBP, hence decreasing cytotoxicity and enhancing resistance to calcification (Maizato et al, 2003).…”

“…Glutaraldehyde-preserved bovine pericardium (GPBP) is widely used in cardiovascular surgery with good results and is one of the most used biological patches (Crawford et al, 1986;David, 1998). However, it is well known that GPBP is subjected to degenerative processes involving rigidity, calcium deposition and structural changes after implantation in humans with the subsequent bioprosthesis failure, mainly due to glutaraldehyde residues and host's immune system (Schmidt and Baier, 2000;Gendler et al, 1984;Beauchamp et al, 1992;Grimm et al, 1992).…”

Controlled Release of Ferric-Magnesium Ions From Chitosan/Polyethylene Vinyl Acetate Comatrix for Preventing Pericardial Calcification

“…The hearts were transported to the lab in cold saline, and the pericardia were gently removed. Fat and excess tissues were stripped off from the bovine pericardia and processed within 4 h of slaughter (Chandy et al 1996). A ventral rectangular sample approximately 6 cm by 6 cm with a thickness of 400 l m was excised from each pericardial sac.…”

“…Levy et al (1991) have developed a polyethylene vinyl acetate (PEVAc) matrix for delivering synergistic drug combinations of Fe 3+ and diphosphonates, for preventing tissue calci® cation. Recently, we have reported the in vitro and in vivo ef® cacy of prolonged-release chitosan matrices, containing protamine sulfate and ferric chloride to inhibit polyurethane and tissue associated calci® cation (Chandy et al 1994(Chandy et al , 1996. Other reports have shown that the preincubation of glutaraldehyde-modi® ed bovine pericardium with certain metallic ions, such as Al 3+ , Fe 3+ , Mg 2+ , Co 2+ , and others, could effectively reduce pathologic calci® cation in the long-term rat subdermal model (Pathak et al 1990;Levy et al 1991;Tung et al 1992;Chandy and Sharma 1993 The purpose of the present study was to assess the possibility of delivering Fe 3+ /Mg 2+ ions from a comatrix system, fabricated from ferric chloride-loaded chitosan beads embedded in magnesium-loaded PE(VAc).…”