Phasic activity of human dorsal foot veins

Phasic contractions of the dorsal foot veins were detected in 7 male subjects, aged 23 to 49 years, by means of a linear variable differential transformer (LVDT) after congesting the veins by a pressure of 6.7 kPa (50 torr). This phasic activity (PA) had a frequency of 3 to 7 contractions per minute and led to a periodic diminution of the diameter of the distended veins by 12 to 44%. Using a double LVDT, the PA was shown to represent peristaltic waves travelling along the vessel wall concomitantly with the venous return. Determined in 3 out of the 7 subjects, the velocity of the waves amounted to 3.6 to 6.1 mm per second. A rheological significance of the peristaltic waves is assumed.