New engineering treatment of bovine pericardium confers outstanding resistance to calcification in mitral and pulmonary implantations in a juvenile sheep model

J Thorac Cardiovasc Surg. 2014 Dec;148(6):3194-201. doi: 10.1016/j.jtcvs.2014.08.002. Epub 2014 Aug 7.

Abstract

Objective: To conduct a test of noninferiority for CardioCel (Admedus, Brisbane, Australia), a chemically engineered bovine pericardium over autologous pericardium treated intraoperatively with glutaraldehyde in a chronic juvenile sheep model of pulmonary valve (PV) and mitral valve (MV) reconstruction.

Methods: We replaced the posterior leaflet of the MV and of 1 PV cusp with patches in ewes aged 10 months. There were 2 groups: CardioCel (n = 6) and control (n = 4). All valves were competent. Echocardiography was performed before euthanasia. The collected data were function, macroscopy, histology, and calcium contents. The primary end points were thickening and calcium content.

Results: All animals survived until sacrifice after 7 months. The valves had normal echo. The macroscopic aspect of the valves was excellent. Examination of the slides for both groups revealed a continuous endothelium on both sides of the patch and a layer of new collagen developed on both sides between patch and endothelium and interstitial cells and smooth muscle cell in these layers. The patch had not thickened but the 2 layers of new collagen for the PV showed a median thickening of 37% in the CardioCel group and 111% in the control group (P = .01), and for the MV a thickening of 108% and 251%, respectively, was seen (P = .01). The median calcium content in the PV was 0.24 μg/mg (range, 0.19-0.30) in the CardioCel group versus 0.34 μg/mg (range, 0.24-0.62) in controls (P = .20). In the MV it was 0.46 μg/mg (range, 0.30-1.0) in the CardioCel group and 0.47 μg/mg (range, 0.29-1.9) in controls (P = 1.0).

Conclusions: In this growing lamb model the CardioCel patch allowed accurate valve repair at both systemic and pulmonary pressure. The mechanical properties of CardioCel after 7 months were preserved with a more controlled healing than the treated autologous pericardium and without calcification.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Animals
  • Autografts
  • Bioengineering / methods*
  • Calcinosis / diagnosis
  • Calcinosis / etiology
  • Calcinosis / metabolism
  • Calcinosis / prevention & control*
  • Calcium / metabolism
  • Cardiac Surgical Procedures / adverse effects
  • Cardiac Surgical Procedures / instrumentation*
  • Cardiac Surgical Procedures / methods
  • Cattle
  • Collagen / metabolism
  • Cross-Linking Reagents / pharmacology
  • Female
  • Glutaral / pharmacology
  • Hemodynamics
  • Heterografts
  • Mitral Valve / diagnostic imaging
  • Mitral Valve / metabolism
  • Mitral Valve / pathology
  • Mitral Valve / physiopathology
  • Mitral Valve / surgery*
  • Models, Animal
  • Pericardium / diagnostic imaging
  • Pericardium / drug effects
  • Pericardium / metabolism
  • Pericardium / transplantation*
  • Pulmonary Valve / diagnostic imaging
  • Pulmonary Valve / metabolism
  • Pulmonary Valve / pathology
  • Pulmonary Valve / physiopathology
  • Pulmonary Valve / surgery*
  • Sheep
  • Time Factors
  • Ultrasonography
  • Wound Healing

Substances

  • Cross-Linking Reagents
  • Collagen
  • Calcium
  • Glutaral