This is an important distinction to make because Doppler US can be used to evaluate for this metric via peak systolic velocities. Labropoulos et al [45] and Metzger et al [46] agree that a peak systolic velocity ratio >2.5 across the stenosis (poststenotic velocity to prestenotic velocity) as an accurate criterion to use for the presence of a pressure gradient of 3 mm Hg. Doppler US can thus be used to determine candidacy for intervention and also monitor success of treatment on follow-up. Variant 4: Venous leg ulcer. Treatment. Compression Therapy Compression therapy has been widely described as a helpful initial treatment for VLU [18-20]. Compression therapy involves the use of a wide varying degree of devices to provide extrinsic compression on the lower extremity. As a group, they reduce venous stasis in various ways. Edema is contained by reduction of capillary filtration, fluid shift into noncompressed regions, and improved lymphatic drainage. Veins are directly affected by increasing venous blood flow velocity, reducing blood pooling, and improving venous pumping function. Lastly, microcirculation is influenced by transient increases in sheer stress, which in turn causes the release of anti- inflammatory, vasodilating, and antithrombotic mediators [19,47]. When using compression therapy, a minimum pressure of 20 to 30 mm Hg is recommended. Pressures of 30 to 40 mm Hg are advised for more severe disease [20]. Of note, improved ejection fraction in refluxing vessels and higher extrinsic pressures were achieved when higher pressures were exerted at the calf over the distal ankle (negative graduated compression bandage). The alternative, graduated compression bandage, in which more force is generated at the distal ankle over the calf, demonstrated inferior ejection fraction in refluxing vessels and lower extrinsic pressures compared with their negative graduated compression bandage counterparts.
Lower Extremity Chronic Venous Disease. This is an important distinction to make because Doppler US can be used to evaluate for this metric via peak systolic velocities. Labropoulos et al [45] and Metzger et al [46] agree that a peak systolic velocity ratio >2.5 across the stenosis (poststenotic velocity to prestenotic velocity) as an accurate criterion to use for the presence of a pressure gradient of 3 mm Hg. Doppler US can thus be used to determine candidacy for intervention and also monitor success of treatment on follow-up. Variant 4: Venous leg ulcer. Treatment. Compression Therapy Compression therapy has been widely described as a helpful initial treatment for VLU [18-20]. Compression therapy involves the use of a wide varying degree of devices to provide extrinsic compression on the lower extremity. As a group, they reduce venous stasis in various ways. Edema is contained by reduction of capillary filtration, fluid shift into noncompressed regions, and improved lymphatic drainage. Veins are directly affected by increasing venous blood flow velocity, reducing blood pooling, and improving venous pumping function. Lastly, microcirculation is influenced by transient increases in sheer stress, which in turn causes the release of anti- inflammatory, vasodilating, and antithrombotic mediators [19,47]. When using compression therapy, a minimum pressure of 20 to 30 mm Hg is recommended. Pressures of 30 to 40 mm Hg are advised for more severe disease [20]. Of note, improved ejection fraction in refluxing vessels and higher extrinsic pressures were achieved when higher pressures were exerted at the calf over the distal ankle (negative graduated compression bandage). The alternative, graduated compression bandage, in which more force is generated at the distal ankle over the calf, demonstrated inferior ejection fraction in refluxing vessels and lower extrinsic pressures compared with their negative graduated compression bandage counterparts.