Elasticity and compliance of canine femoral and jugular vein segments

In this study, the pressure/strain and stress/strain relatioships of 44 jugular and 31 femoral canine vein segments were compared with 17 carotid artery specimens, latex rubber, and a synthetic graft material, expanded polytetrafluoroethylene. A method is described for comparing the elastic properties of vein wall specimens of varying thicknesses such as occur after implantation into the arterial circulation. A flat sheet of opened vessel wall, fexed between retention rings at one end of a saline-filled steel cylinder, was biaxially distended to form a bubble shape. Compliance ratio and stress modulus were computed at 20-mmHg increments from 20 to 200 mmHg. In the "arterial" pressure range, vein was less compliant than artery. Vein also had a higher stress modulus E (dyn/cm2 X 10(6)) +/- SE at a chamber pressure 120 mmHg than artery (E = 11 +/- 0.6), and jugular vein was stiffer (E = 65 +/- 3.6) than femoral vein (E = 41.5 +/- 2.0). Changes in the structural properties of vein grafts measured using this technique are potentially important factors leading to graft failure.