The telescoping suture--Part II: A novel method to improve the mechanical behavior of a new biomaterial: ostrich pericardium

Ostrich pericardium, sutured using a telescoping or overlapping technique, was studied to determine its mechanical behavior. From each of 12 pericardial sacs, four contiguous strips were cut longitudinally, from root to apex, and another four contiguous strips were cut in transverse direction. One of the strips in each set of four was used as an unsutured control and the remaining three were sutured by overlapping 0.5 cm of the tissue and sewing with Gore-tex, Prolene or Pronova. These 96 samples were then subjected to tensile testing along their major axes until rupture. The tensile stresses recorded in the suture materials at the moment tears appeared in the pericardium ranged between 55.99 MPa and 70.23 MPa for Gore-tex in samples cut in the two directions. Shear stress became ostensible at 56 MPa, with clearly evident tears. However, microfracture of the collagen fibers must be produced at much lower stress levels. The comparison of the resistance in kilograms (machine-imposed), without taking into account the sections in which the load was applied, demonstrated only a slight loss of load when the telescoping suture was employed in ostrich pericardium samples. Ostrich pericardium may continue to be an alternative biological material for the construction of heart valve leaflets.