Clinical and hemodynamic significance of the greater saphenous vein diameter in chronic venous insufficiency.

HYPOTHESIS As the compliant greater saphenous vein (GSV) adjusts its luminal size to the level of transmural pressure, measurement of its diameter, reflecting the severity of hemodynamic compromise in limbs with GSV reflux, may simplify the hemodynamic criteria of patient selection for saphenectomy. OBJECTIVE To evaluate the clinical significance of GSV diameter determined in the thigh and calf as a marker of global hemodynamic impairment and clinical severity in a model comprising patients with saphenofemoral junction and truncal GSV incompetence. DESIGN A cohort study. SETTING University-associated tertiary care hospitals in Brazil and England. PATIENTS Eighty-five consecutive patients, aged 28 to 82 (mean, 46.2) years; 112 lower limbs with saphenofemoral junction and truncal GSV incompetence were investigated. INTERVENTIONS Clinical examination was followed by clinical, etiological, anatomical, and pathophysiological classification (CEAP), vein duplex, and air plethysmography. The GSV diameter was measured on standing at the knee, and at 10, 20, and 30 cm above and below the knee, and in the thigh and calf, respectively, using B-mode imaging. The venous filling index (VFI), venous volume (VV), and residual volume fraction (RVF) were measured by air plethysmography. MAIN OUTCOME MEASURES The GSV diameter was correlated with the VFI, VV, RVF, and CEAP. The value of the GSV diameter for predicting the presence of critical reflux (VFI >7 mL/s) or the absence of abnormal reflux (VFI <2 mL/s) was determined with receiver-operator curves. RESULTS The GSV diameter increased significantly overall with CEAP (P<.001) and also increased progressively with proximity to the saphenofemoral junction. The VFI, VV, and RVF increased significantly from CEAP(0) through CEAP(4-6); the VFI correlated well with VV, RVF, and CEAP (P<.001 for all). The GSV diameter at all 7 limb levels studied correlated well with VV (except at the distal calf), VFI, RVF, and CEAP (P< or =.009 for all). A GSV diameter of 5.5 mm or less predicted the absence of abnormal reflux, with a sensitivity of 78%, a specificity of 87%, positive and negative predictive values of 78%, and an accuracy of 82%. A GSV diameter of 7.3 mm or greater predicted critical reflux (VFI >7 mL/s), with an 80% sensitivity, an 85% specificity, and an 84% accuracy. CONCLUSION The GSV diameter proved to be a relatively accurate measure of hemodynamic impairment and clinical severity in a model of saphenofemoral junction and GSV incompetence, predicting not only the absence of abnormal reflux, but also the presence of critical venous incompetence, assisting in clinical decision making before considering greater saphenectomy.