A single complete ultrasound investigation of the venous network for the diagnostic management of patients with a clinically suspected first episode of deep venous thrombosis of the lower limbs.

In patients clinically suspected of deep-vein thrombosis (DVT) of the lower limbs, it is safe to withhold anticoagulant therapy after a negative ultrasound (US) limited to the popliteal and the femoral veins, provided that this can either be repeated or combined with other diagnostic procedures. To assess the safety of withholding anticoagulants after a single negative complete US, we performed a multicenter, prospective, cohort study including consecutive ambulatory outpatients from institutional and private practice settings, with a clinically suspected first episode of DVT. Patients fulfilling the inclusion criteria were enrolled after careful clinical assessment.