Deep vein thrombosis of the leg

Thrombus formation (blood clot) in the deep veins of the leg. The veins may be completely or partially occluded (blocked) by the clot. When the clot only partially occludes the vein, the body’s natural factors can usually dissolve it with time.
Deep vein thrombosis (DVT) of the leg can give rise to pain and swelling of the calf or leg, but may not cause any symptoms at all. Thrombosis may occur in various medical conditions, such as heart disease and cardiac failure, after operations, or spontaneously. In addition, DVTs may occur if someone is bedridden or not moving the legs during a long-distance flight (economy class syndrome). There is a particular risk of developing thrombosis if the blood flow in the vein is slow and the vein wall is damaged. Platelets accumulate at the damaged site and clump together to form a blood clot. Therefore, thrombosis may develop in untreated varicose veins and with thrombophlebitis.

In the worst case scenario, thrombosis gives rise to pulmonary embolism, when a piece of the clot breaks off and is washed away by the blood until it reaches the lungs, where it blocks blood vessels. Pulmonary embolism may be fatal if the essential vessels in the lungs are occluded.

The diagnosis of DVT can be made with an ultrasound scan. Treatment usually consists of anticoagulants (medicinal products to thin the blood) and compression therapy; sometimes medicinal products are given to dissolve the clot or surgery is performed. DVTs are usually associated with destruction of the valves in the vein, with the result that blood flow in the direction of the heart is no longer guaranteed. CVI (chronic venous insufficiency) may develop as a result.