Use of passive function testing in venous insufficiency: a prospective study.

In a prospective study, the results of venous function tests in 19 lower extremities with deep venous insufficiency and in seven control extremities were compared. First, the routine method of asking the patients to exercise their calves was used. Second, cuffs around the calves were rapidly inflated, producing standardized external compression to the calf muscle pump. Our aim was to decrease the influence of artifacts from involuntary muscle efforts and especially to render reproducible results of pressure reduction after passively pumping. The passive function test proved to be the only technique with which a decrease in pressure measured with strain gauges while the patient was in the standing position could significantly be discriminated between diseased and control extremities. Furthermore, the correlation of pressure decrease invasively versus measured noninvasively improved to 37% and thus became significant. Simulating calf venous pump function with the aid of inflatable cuffs is easily applicable in the vascular laboratory. It enables the vascular surgeon to reliably quantify venous recovery time and pressure reduction.