Jonas Andersson, Anders Thurin, Olav Thulesius
Apr 1, 1996
Journal of vascular surgery
PURPOSE We wanted to answer the question of whether physiological dilation of normal extremity veins can induce temporary valvular leakage and reflux. METHODS Directional flow was recorded in 22 forearm and popliteal veins by Doppler duplex scanning after distal compression. Reflux was assessed by valve closure time and calculation of a "reflux index," the ratio of backward to forward flow areas. RESULTS Hyperemia and enhanced flow did not increase but lowered reflux. During control conditions the mean reflux ratio (backward/forward flow area) of 21 veins was 0.058 and decrease to 0.028 (p < 0.05). Reflux was slightly longer in patients in the erect position in the popliteal vein, compared to forearm veins (with the patients in the sitting position). Significantly increased reflux occurred during hyperemia in only one deep forearm vein (valve closure time 0.92 seconds). CONCLUSIONS Most veins of the upper (forearm) and lower extremity (popliteal vein) were competent even after a maneuver that induced venodilation and an increase in blood flow (exercise hyperemia or postocclusion reactive hyperemia). Veins with an inherent valvular weakness can be identified by a hyperemia test with duplex flow analysis.