The relationship between stress and relaxation in calf pericardium used in the construction of cardiac bioprostheses

Biomaterials. 1990 Apr;11(3):186-90. doi: 10.1016/0142-9612(90)90153-h.


Assessment of relaxation (loss of load within a given time) without apparent deformation is a necessary step before durability assay of biomaterials. From results obtained using calf pericardium, the following conclusions were drawn: (a) there is no limit to relaxation for this biomaterials; (b) the lesser the load applied, the greater the relaxation; and (c) the relaxation curve follows the logarithmic function y = K1 - K2 - Int. These findings demonstrate the poor behaviour of the biomaterial at supposedly low loads and suggest that rupture-point load is not a reliable reference to determine the safety coefficient of calf pericardium used in cardiac bioprostheses.

MeSH terms

  • Animals
  • Biomechanical Phenomena
  • Bioprosthesis*
  • Cattle
  • Heart Valve Prosthesis*
  • In Vitro Techniques
  • Pericardium / physiology*
  • Stress, Mechanical
  • Tensile Strength