Should a known dvt in the leg be monitored with regular ultrasounds to ensure dvt has not moved or got bigger or no new dvt's have developed?

Not useful: The DVT can take up to 6 months to dissolve completely on blood thinners (Coumadin or 1 of the newer agents) for the time period specified by your doctor. While ultrasound is useful in detecting a DVT (due to Doppler), it is less useful in showing how big/small the clot is over time. Your best bet is warfarin: that has shown to prevent migration of even small flecks of the clot. Se HealthTap Prime

DVT and ultrasound.: Once a DVT is fully treated then there is no need for further ultrasounds unless symptoms develop. If a patient has symptoms of chronic venous insufficiency or if I am concerned about developing post phlebitic syndrome then I would do a venous ultrasound to follow this.