What Are the Signs and Symptoms of Thrombosis?
The major symptoms of thrombosis are pain in the affected area and swelling, which can occur suddenly. If the thrombosis involves a leg vein, the leg also might appear red and feel warm to the touch. Veins close to the skin surface may look larger than normal and reddish-blue in color. The biggest danger is when a clot forms in the large veins that are deep within the legs. If the blood clot grows, it may break off. The clot may then travel toward and then through the heart and block the pulmonary* artery, which is a major blood vessel, causing a pulmonary embolism*. This serious complication of thrombosis may cause death if not treated rapidly and effectively.