Quantifying saphenous recirculation in patients with primary lower extremity venous reflux.

BACKGROUND: The great saphenous vein (GSV) in patients with superficial venous insufficiency might act as a beneficial conduit for antegrade venous drainage and also as a harmful conduit for promotion of reflux and/or recirculation and subsequent skin changes. The aim of this study was to measure the antegrade and retrograde GSV volume displacements during calf compression and release maneuvers. This was used to quantify harm over benefit with a recirculation index (RCI).

METHODS: Sixteen legs (nine right) from 16 patients (nine male) with primary superficial venous insufficiency were scanned standing with duplex ultrasound, at the upper thigh GSV, 10 cm below the sapheno-femoral junction. The clinical, etiological, anatomical, pathophysiological class was C2 = 3, C3 = 2, C4a = 6, C4b = 4, C5 = 1. The median age (range), venous clinical severity score, and refluxing GSV diameter were 63 (21-79) years, 8 (4-16), and 7 (5-10) mm, respectively. A manual calf compression and release (MCCR) maneuver was performed once, and a cyclical calf compression and release (CCCR) three times for repeatability. With the CCCR maneuver, the calf-cuff and inflation-deflation pump provided a cyclical compression pressure of 120 mm Hg (3 seconds) with a release time of 16.4 seconds to standardize venous refilling time.

RESULTS: The results are expressed as median [interquartile range]. The CCCR compared with the MCCR resulted in longer reflux duration (16.4 [8.2-16.4] seconds vs 5.7 [3.7-6.8] seconds; P < .0005), higher time-averaged mean velocities in reflux (23.5 [14.9-27.9] cm/s vs 14.1 [9-17.6] cm/s; P < .0005) and greater reflux volume displacements (81.7 [38.8-152.8] mL vs 27.3 [16.4-53.4] mL; P < .0005). There were significant correlations between increasing antegrade volume measurements and increasing reflux volume measurements irrespective of whether CCCR, (r = 0.841; P < .0005) or MCCR (r = 0.762; P = .001) was used. This implies that the displaced antegrade volume might have a causal effect on the resulting reflux volume. The ratio of reflux volume/antegrade volume (RCI) was 2.14 [1.58-2.74] with the CCCR. This supports the recirculation phenomenon. Adjusted to a standard median for each leg, the repeatability limits (three times) of the RCI was excellent at 2.14 (95% confidence interval, 2.09-2.21).

CONCLUSIONS: In this study we measured the behavior of the GSV in terms of harmful reflux over beneficial drainage using the RCI. We recognize that reflux values depend on the type of provocation test and the amount of displaced antegrade volume. This limitation might be overcome by factoring reflux as an expression of antegrade flow using the RCI. When standardized, a test for quantifying saphenous recirculation might have many clinical applications. The next step should be a prospective study to validate the RCI with clinical and quality of life parameters.