Utility of lower-extremity duplex sonography in patients with venous thromboembolism.

PURPOSE: We evaluated the utility of venous duplex ultrasonography (VDUS) of the lower extremities in patients with pulmonary embolism (PE) and studied the distribution of venous thrombi in deep vein thrombosis (DVT) patients with and without PE.

METHODS: We retrospectively reviewed medical records of all inpatients with a final diagnosis of PE or DVT between 1989 and 2000.

RESULTS: Venous thrombosis was detected by VDUS in 229 patients (191 without PE and 38 with PE). The left leg only was involved in 50% of patients (p < 0.05), the right leg only in 33%, and both legs in 17%. The overall distribution of veins affected by DVT was: popliteal vein, 77%; superficial femoral vein, 76%; common femoral vein, 65%; posterior tibial vein, 23%; external iliac vein, 21%; common iliac vein, 9%; great saphenous vein, 7%; and inferior vena cava, 2%. A single venous site was involved in 22% of patients. External iliac vein thrombosis was more frequent in patients with DVT only (24%) than with PE and DVT (5%) (p < 0.05). The venous obstruction was partial in 14% of patients. VDUS of the asymptomatic leg was positive in 14% of patients with unilateral symptoms of DVT, all of whom also had DVT in the symptomatic leg. VDUS was positive for DVT in 90% of patients with PE and concomitant pain or edema of the leg, compared to only 20% of PE patients with no symptoms of DVT.

CONCLUSIONS: Sonography should be the first diagnostic test for patients suspected of having PE with any sign or symptom related to DVT. VDUS of the asymptomatic leg is unnecessary in the diagnosis and management of DVT. Omitting the superficial femoral vein examination would lead to some decrease in the sensitivity of VDUS.