Measurement of ambulatory venous pressure and column interruption duration in normal volunteers.

BACKGROUND

Ambulatory venous pressure (AMVP) measurement is considered the gold standard in evaluating calf pump function in chronic venous disease. The AMVP protocol was standardized in the 1970s with pressure monitoring through the dorsal foot vein. This technique was based on the belief that it represents calf venous pressure dynamics owing to rapid equilibration in the superficial and deep systems. This notion is subject to some doubt not only on theoretical grounds, but also owing to a lack of clinical correlation in a segment of the population with chronic venous disease. Our aims were to (1) examine if AMVP measured simultaneously through the dorsal foot vein (DFV) and the great saphenous vein (GSV) would be similar and (2) attempt to devise a noninvasive substitute via duplex measurement for the AMVP test.

METHODS

The study was conducted in 76 limbs in 38 normal volunteers. Simultaneous AMVP measurements in DFV and GSV were made in 28 of these normal limbs. Column interruption duration (CID) after calf pump ejection was measured by monitoring duplex resumption of flow in the tibial veins and GSV after calf ejection. The return of AMVP back to baseline implies column restoration. The venous refill time therefore represents the CID via the pressure method. The pressure and duplex methods of CID were compared in the GSV.

RESULTS

Key AMVP parameters (percent drop and venous refill time) significantly differed in DFV and GSV, showing a lack of pressure equilibration. CID measured by duplex in GSV was not significantly different from pressure-derived CID in the same vein.

CONCLUSIONS

AMVP measured through the DFV does not reflect calf pump generated pressure events in GSV. A duplex method of measuring CID in GSV and posterior tibial vein is described. Duplex-derived CID is not significantly different from pressure-derived CID in the GSV.