Disease relevance of Bioprosthesis

• Calcification resulting in stenosis of the glutaraldehyde-treated bioprosthesis has been reported infrequently [1].
• An analysis is presented of 236 patients aged greater than or equal to 20 years who underwent isolated mitral valve replacement for rheumatic heart disease with a glutaraldehyde Hancock bioprosthesis from June 1974 through June 1978 [2].
• Five cases of Brucella infective endocarditis are described involving a native aortic valve, two native mitral valves, a mitral valve bioprosthesis, and a ventricular septal defect patch [3].
• Prevention of thromboembolism with ticlopidine shortly after valve repair or replacement with a bioprosthesis [4].
• BACKGROUND AND AIMS OF THE STUDY: In the production of porcine bioprostheses, the initial glutaraldehyde treatment is often followed by a short incubation in formaldehyde to ensure sterility of the valve [5].

High impact information on Bioprosthesis

• In addition, patients with bioprostheses without warfarin anticoagulation had better survival and event-free survival than those with bioprostheses taking warfarin and those with mechanical prostheses with or without warfarin [6].
• These results predict that calcification will critically limit the late durability of clinical pericardial bioprostheses and suggest generalized mechanisms of bioprosthetic tissue mineralization which are probably dependent on modification of implant microstructure by glutaraldehyde pretreatment [7].
• Microdeposits of amyloid were present in the sewing ring of the fascia lata valve and in 10 porcine bioprostheses, and this finding was confirmed by transmission electron microscopy in 3 porcine bioprostheses [8].
• The Hancock II bioprosthesis, which is currently undergoing clinical investigation, is made from a porcine aortic valve treated with a calcium-retarding agent (sodium dodecyl sulfate [T6]), which should delay onset of calcification and increase durability [9].
• In 42 patients with a normal Hancock porcine bioprosthesis (standard model, sizes 27 to 33 mm), mean diastolic flow (65 to 461 ml/s), mean gradient (2.0 to 13.4 mm Hg) and effective orifice area (1.1 to 4.4 cm2) were determined at rest, during epicardial pacing (90, 110 and 130/min) and with isoproterenol infusion [10].

Biological context of Bioprosthesis

• beta-Thromboglobulin (beta TG), platelet factor 4 (PF4), fibrinopeptide A (FPA), lactic dehydrogenase (LDH), and platelet count were evaluated in patients with bioprostheses and prosthetic heart valves. beta TG and PF4 were significantly elevated in both patient groups (p less than 0.001), whereas FPA was normal [11].
• Selected specimens of calcified bioprostheses underwent histology, transmission (TEM) and scanning (SEM) electron microscopy [12].

Anatomical context of Bioprosthesis

• In an effort to normalize the dynamic leaflet behavior of a porcine bioprosthesis, an experimental attempt was made to treat a tissue heart valve with 0.625% glutaraldehyde in the open position ("open-type valve") [13].
• Oral anticoagulation with coumarin derivatives may not be appropriate after mitral valve replacement with a bioprosthesis, and platelet antiaggregates should be used for this purpose in the future [14].
• The mechanoelastic behavior of calf pericardium employed in cardiac bioprostheses was compared with that of three types of thread (Nylon, Prolene, and silk) used to suture this biological tissue [15].
• We report 3 consecutive patients with tricuspid insufficiency who underwent valve replacement with glycerol-preserved, homologous dura mater cardiac bioprostheses between 1971 and 1973 [16].
• We conclude that bioprosthetic heart valve materials can be lined with endothelial cells if toxic glutaraldehyde released from the bioprostheses is eliminated [17].

Associations of Bioprosthesis with chemical compounds

• In a majority of porcine bioprostheses amyloid was permanganate-sensitive and tryptophan-positive [8].
• Effect of ethanol and ether in the prevention of calcification of bioprostheses [18].
• Currently available crosslinking agents and sterilants used in the fixation or sterilization of biological tissues such as glutaraldehyde and formaldehyde are all highly cytotoxic, which may impair the biocompatibility of bioprostheses [19].
• Heparin in calcification prevention of porcine pericardial bioprostheses [20].
• Stent mounted bioprostheses were prepared either sequentially as previously described or differentially with AlCl3 exposure restricted to the aortic wall followed by ethanol pretreatment [21].

Gene context of Bioprosthesis

• There was no significantly difference in plasma concentrations of beta TG and PF4 between patients with prosthetic heart valves and bioprostheses [11].
• CONCLUSIONS: VEGF gene transfer by surgical suture can remarkably accelerate endothelialization of bioprosthesis, which may provide a new approach for inhibiting biological valve calcification and improve biocompatibility and long-term durability of the bioprosthesis [22].
• CONCLUSIONS: This study suggests that the Prima valve is a reliable stentless aortic bioprosthesis [23].
• Elastin-associated degeneration and calcification are potential causes of long-term failure of glutaraldehyde (Glut) fixed tissue bioprostheses used in cardiovascular surgery [24].
• Such a tubular tissue valve, the 3F Aortic Bioprosthesis (3F Therapeutics, Inc, Lake Forest, Calif) was designed and tested in vitro against a commercially available stentless aortic bioprosthesis [25].

Analytical, diagnostic and therapeutic context of Bioprosthesis

• The report of a failure of glutaraldehyde-preserved porcine aortic xenograft bioprosthesis in the aortic position after 13 months is presented [26].
• The hemodynamic function of the Hancock bioprosthesis was evaluated in 77 patients who underwent cardiac catheterization of rest and with isoproterenol infusion (15 patients) an average of 6 months after operation [27].
• To determine mechanisms responsible for the reduced calcification in short-term glutaraldehyde (Glu)-treated autologous pericardial bioprostheses, we studied the time effect of Glu on subsequent calcification and differences in calcification of autograft and xenograft implants in a rat subcutaneous implantation model [28].
• All survivors, except for those who received a bioprosthesis, were placed on a regimen of Phenprocoumon (Marcumar((R))), aiming to maintain the International Normalized Ratio (INR) between 2.5 and 3 [29].
• The bioprostheses used were Carpentier-Edwards porcine or pericardial (n = 158) valves, Prima stentless valves (n = 3) and cryopreserved homografts (n = 7) [4].

References