Quantitative Evaluation of Calf Muscle Pump Function after Deep Vein Thrombosis by Non-Invasive Venous Tests

Abstract

In order to quantitatively evaluate calf muscle pump function following deep vein thrombosis (DVT), expelled volume was investigated by strain gauge plethysmography (SPG). Thirty-six patients with 43 diseased lower limbs and nine healthy persons with 16 control limbs were studied. Of 43 diseased limbs, 20 symptomatic limbs were distinguished from 23 asymptomatic limbs by the presence of heaviness or aching. The following ***noninvasive parameters for the quantitative evaluation of calf muscle pump function, venous refilling time (VRT), venous outflow (VO), venous return (VR), and expelled volume (EV) were measured by SPG or photoplethysmography (DPG). Ambulatory venous pressure (AVP) was taken to represent the standard for calf muscle pump function. Using SPG, the EV, VR, and VRTs distinguished three groups (control, asymptomatic and symptomatic). Among seven indicators (EV, VR, VO, VRTs), EV had the highest correlation coefficient with the AVP (r = +0.728). A positive EV was present in 85% of the symptomatic limbs, but in only 4% of the asymptomatic limbs. It is concluded that the EV is a useful non-invasive indicator for the quantitative evaluation of calf muscle pump function after deep vein thrombosis.