Pressure-Volume Characteristics of Foot Veins in Normal Cases and Patients with Venous Insufficiency

Abstract

In order to evaluate pressure-volume characteristics of foot veins in patients with venous insufficiency compared with a control group, the foot-volumetric method was utilized, combined with intravenous pressure measurements. Calculations of compliance and elastance were performed within a fixed pressure interval, where the veins were filled or almost filled. The investigation demonstrates a lower compliance and a higher elastance in the varicose veins compared with the control cases. This is contrary to most previous investigations, in which the veins have not been fully distended, as the measurements were performed in the lying position with rather low venous pressure. Changes of compliance and elastance were most marked in cases with advanced venous disease and skin changes of the ankle region. The observed changes of a ‘greater stiffness’ of the foot-vascular system can be explained by fibrotic or phlebosclerotic changes. In addition to the observations of slightly altered elasticity factors, we observed volume changes after exercise which seem to be related to capillary filtration.