Deep vein thrombosis (DVT) is a blood clot in one of the major deep veins, usually of the lower legs, thighs, or pelvis. A clot blocks blood circulation through these veins, which carries blood from the lower body back to the heart. The blockage can cause pain, swelling, or warmth in the leg. Blood clots in the veins can cause inflammation called thrombophlebitis. If the clot breaks loose and travels through the bloodstream, it can block a blood vessel in the lungs. Called pulmonary embolism, this can lead to severe trouble breathing and even death.
In the U.S., between 300,000 and 600,000 people per year get deep vein thrombosis. About 100,000 people die each year from pulmonary embolism.
Common symptoms when this condition develops in a vein may include:
Red, swollen, and irritated skin and tissue around the area, such as along an affected leg
Painful, warm, tender, or hard sensations in the area
Pain or tenderness that increases when you put pressure on the affected area
A swollen vein that feels like a tough "cord" under your skin
Pain when flexing your ankle
Swollen foot or ankle, especially if only one side is swollen
If you exhibit any of these symptoms,...