Calcific degeneration of pericardial valvular xenografts implanted subcutaneously in rats (original) (raw)
Related papers
The Journal of Thoracic and Cardiovascular Surgery, 2001
Objective: We sought to investigate the durability and mechanism of the Carpentier-Edwards pericardial xenograft in the mitral position in comparison with that of the Ionescu-Shiley pericardial xenograft. Methods: A total of 284 patients who received the Ionescu-Shiley pericardial xenograft in the mitral position between 1980 and 1984 and 84 patients who received the Carpentier-Edwards pericardial xenograft in the mitral position between 1984 and 1999 were included in the study. The freedom from reoperation rates for both graft types were determined. For morphologic study, the pathologic findings of 23 valves of 123 explanted Ionescu-Shiley pericardial xenografts with structural valve deterioration, nonstructural valve deterioration, or both were determined and compared with those of 20 explanted Carpentier-Edwards pericardial xenografts with structural valve deterioration, nonstructural valve deterioration, or both. Each pathologic finding was graded and assigned a score. Both types were matched for age at reoperation (50-75 years) and duration of valve function (8-11 years). Results: Freedom from reoperation caused by structural valve deterioration, nonstructural valve deterioration, or both was significantly better for Carpentier-Edwards pericardial xenografts than for Ionescu-Shiley pericardial xenografts at 8 years after the operation (Carpentier-Edwards pericardial xenografts: 91.3% vs Ionescu-Shiley pericardial xenografts: 71.9%, P = .0061), but it was similar for both types at 12 years (Carpentier-Edwards pericardial xenografts: 43.6% vs Ionescu-Shiley pericardial xenografts: 43.6%, P = .2865). No severe leaflet tears were seen among Carpentier-Edwards pericardial xenografts. The mean area percentage of tissue overgrowth was 15.3% in Carpentier-Edwards pericardial xenografts and 3.4% in Ionescu-Shiley pericardial xenografts (P = .0001). The mean calcification area percentage was 13.6% in Carpentier-Edwards pericardial xenografts and 31.5% in Ionescu-Shiley pericardial xenografts (P = .0001).
Severe calcification of glutaraldehyde-preserved porcine xenografts in children
1980
Despite the widespread use of glutaraldehyde-preserved porcine xenografts, severe short-term calcification of these valves has been infrequently reported. This report describes four cases of glutaraldehyde-preserved porcine xenografts in the mitral valve position in which severe calcification occurred within 17 to 25 months of implantation. All four patients were children, aged 13 to 15 years. The clinical presentation in all four cases occurred at a late stage when there was severe xenograft obstruction, with acute symptoms of cardiac decompensation in the presence of pulmonary hypertension and right heart failure. There was rapid cardiac deterioration resulting in a low output state and episodic pulmonary edema necessitating urgent mitral valve replacement. In only one case was there clear auscultatory evidence of severe mitral stenosis. Calcification of these xenografts occurred in the presence of normal serum calcium levels and was not related to infective endocarditis. Histolog...
Calcification of Chemically Treated Bovine Pericardium
The International Journal of Artificial Organs, 1991
One of the most important problems arising in cardiac bioprostheses made with bovine pericardium and, more generally, with biologically-derived tissues is tissue calcification. The present study assessed four chemical treatments on patches of bovine pericardium, intended to avoid or minimize calcification. Pericardium specimens were treated with: A) 0.5% glutaraldehyde; B) 0.5% glutaraldehyde + 4% formaldehyde; C) same as A, but with a further neutralization treatment; D) acylation of fresh bovine pericardium. Circular samples of 1 cm diameter were subcutaneously implanted in the abdominal region of three groups of six rats. The explants were retrieved after 2, 4 and 8 weeks. The calcium content and the histological results showed better behaviour for C and D samples than with the commonly used fixation methods (A and B). The lowest calcification was observed with treatment D, even though its morphological structures were somewhat modified with homogenation of collagen bundles. Amon...
Interactive CardioVascular and Thoracic Surgery, 2016
OBJECTIVES: The efficacy of anti-calcification treatment of bioprosthetic heart valves remains unclear. The aim of this study was to compare the clinical outcomes between Mitroflow LX valve, without anti-calcification treatment, and the Carpentier-Edwards Perimount Magna (P-Magna), with anti-calcification treatment. METHODS: Between 2005 and 2012, 625 consecutive patients underwent aortic valve replacement either with a Mitroflow LX (n = 329) or a P-Magna (n = 296). Variables regarding patient-related risk factors and operative data were accounted for an inverse probability of treatment weighting analysis. Then, adjusted survival outcomes and the rate of structural valve disease (SVD) were assessed for each group. RESULTS: Mean follow-up times were 4.1 ± 2.29 years and 3.9 ± 2.63 years, respectively (P = 0.34). Adjusted overall survival rate was higher in the P-Magna group than in the Mitroflow LX group at 8 years (69.1% vs 51.9%, respectively) [HR = 1.44, 95% CI: 1.01 to 2.06; P = 0.0467]. Similarly, the 8-year cardiac-related survival rate was also higher in the P-Magna group [HR = 1.99, 95% CI: 1.19 to 3.32; P = 0.0083]. One patient (0.8%) with P-Magna and 23 patients (18.5%) with Mitroflow LX group developed SVD (0.24% per patient-year vs 4.5% per patientyear, respectively; P < 0.001). At 5 and 8 years, valve-related survival rates did not differ significantly between both groups [HR = 1.67, 95% CI: 0.95 to 2.95; P = 0.075]. CONCLUSIONS: The P-Magna prosthesis showed significantly better overall and cardiac-related survival than the Mitroflow LX. The higher early SVD and reoperation rates seen with the Mitroflow LX prosthesis did not impact negatively on valve-related survival.
The meadox-gabbay pericardial xenograft: Failure of the unicusp principle☆
The Annals of Thoracic Surgery, 1992
Durability of a new bioprosthesis, the Meadox-Gabbay unileaflet pericardial xenograft, was evaluated by reviewing a series of 12 patients who received this device in the mitral position from 1983 to 1985. Bioprosthetic failure necessitated reoperation in 5 patients 21, 22, 53, 66, and 81 months after placement. Three patients died of cardiac failure after 31, 52, and 70 months; no postmortem examinations were done. In 2 of the 3 patients, an echocardiographic study had shown signs of valvular dysfunction. Pathological examination of five available explants revealed the presence of redundancy and stretching of the single pericardial leaflet in all of them; he Meadox-Gabbay pericardial xenograft (Meadox
The Pathology of Cardiac Xenografts
Journal of Cardiac Surgery, 2001
The pathology of cardiac xenografts has yielded critical insights into the mechanisms of xenograft rejection and the therapeutic procedures that might be applied to preventing or treating it. The conditions seen in rejecting cardiac xenografts include hyperacute rejection, acute vascular rejection, and cellular rejection. Hyperacute and acute vascular rejection of cardiac xenografts have features typical of humoral injury. Less is known about cellular rejection and only speculation can be offered about chronic rejection. Still, these features allow critical testing of pathogenetic mechanisms and therapies.
Early Experience With Preclinical Perioperative Cardiac Xenograft Dysfunction in a Single Program
The Annals of Thoracic Surgery, 2019
Background.-Peri-operative cardiac xenograft dysfunction (PCXD) was described by McGregor et al. to be a major barrier to the translation of heterotopic cardiac xenotransplantaton into the orthotopic position. It is characterized by graft dysfunction in the absence of rejection within 24-48 hours of transplantation. We describe our experience with PCXD at a single program. Methods.-Orthotopic transplantation of genetically engineered pig hearts was performed in 6 healthy baboons. The immunosuppression regimen included induction by anti-CD20 mAb, Thymoglobulin, cobra venom factor and anti-CD40 mAb and maintenance with anti-CD40 mAb, MMF and tapering doses of steroids. Telemetry was used to asses graft function. Extracorporeal membrane oxygenation was used to support one recipient. A full human clinical transplant team was involved in these experiments and the procedure was performed by skilled transplant surgeons.
Calcification in porcine xenograft valves in children
American Journal of Cardiology, 1980
Calcification developed in the degenerating collagen of the cusps of three porcine xenograft heart valves implanted in children for less than 4 years. The morphologic features and effects of this calcification are presented. Calcification of porcine xenografts seems to occur more frequently and at an earlier stage after insertion in children than in adults. Host factors, possibly related to calcium homeostasis, may promote calcification; hence, these valves may not be appropriate for use in children.