Intravenous pressure changes in patients with postthrombotic deep venous obstruction: results using a treadmill stress test

Background Little is known about the hemodynamic consequences of deep venous obstructive disease. Objectives The aim of this study was to investigate the hemodynamic effect of postthrombotic obstruction of the iliofemoral veins and to determine what pressure parameters differentiate best between limbs with post-thrombotic obstructive disease of the iliofemoral veins and those without obstruction. Methods Twenty-two participants with unilateral obstruction of the iliac and common femoral veins underwent a standardized treadmill test with simultaneous bilateral invasive pressure measurements in the common femoral vein and dorsal foot vein. Results Mean age was 42.811.9years and 86.4% of participants were female. Postthrombotic limbs showed a mean common femoral vein (CFV) pressure increase of 28.121.0mmHg after walking, compared with 2.1 +/- 6.2mmHg in control limbs (26.0mmHg difference; 95% confidence interval [CI], 17.1-34.9). Lessdifference was observed in the dorsal foot vein (net drop of 36.8 +/- 22.7mmHg in affected limbs vs. 48.7 +/- 23.1mmHg in non-affected limbs, 11.9mmHg difference; 95% CI, -1.3 to 25.0). Change in CFV pressure after walking yielded the best discrimination between affected and non-affected limbs (area under the receiver operated characteristic curve of 0.94 [95% CI, 0.85-1.00], compared with 0.57 [95% CI, 0.37-0.76] in the dorsal foot vein, P