The influence of haemodynamics on the structure and organisation of experimental red thrombi.

The organisation of thrombi, induced by thrombin, was compared in the femoral arteries and veins of dogs in an attempt to investigate the effect of differences in intraluminal pressure on this process. All thrombi possessed a peripheral zone of fibrin, leucocytes and clumps of platelets but this was much thicker and more compact in arterial than in venous thrombi possibly resulting from the higher pulse pressure in the former type of vessel. Where organisation occurred it was predominantly peripheral or marginal and was obviously much more exuberant in arteries than in veins. Thus the extent of such organisation seemed related directly to the thickness of this peripheral zone which in turn was largely dictated by the pulse pressure in the vessel concerned.