[Diagnosis and treatment of venous thrombosis]

In the diagnosis of deep vein thrombosis in ambulatory patients, the recommended initial steps are assessment of clinical probability (CP) and a sensitive D-dimer test. With a low CP and negative D-dimer, thrombosis can be ruled out. All other constellations require further investigation with imaging techniques. Compression ultrasonography is the first-line investigation. Low-molecular weight heparin or fondaparinux is the treatment of choice for uncomplicated venous thrombosis. Secondary prophylaxis with a vitamin K antagonist is introduced in parallel as quickly as possible. The duration of treatment depends on the exposure and predisposing factors, weighing carefully the risk of recurrence on the one hand against the risk of bleeding on the other. The danger of a post thrombotic syndrome is reduced by the immediate begin of a long lasting compression therapy.