Table of Contents
- Blood clot facts
- What are blood clots? What does a blood clot look like?
- What causes blood clots (blood clots in veins or arteries)?
- What causes blood clots (blood clots in the heart, leaking, and other causes)?
- What are the risk factors for blood clots?
- What types of conditions are caused by blood clots (DVT and pulmonary embolism)?
- What types of conditions are caused by blood clots (AFib, atrial thrombosis, and others)?
- What are the signs and symptoms of blood clots?
- What kind of doctors treat blood clots?
- How are blood clots diagnosed?
- What tests are used to diagnose blood clots?
- What is the treatment for blood clots?
- What are the complications of blood clots?
- How can blood clots be prevented?
Quick GuideDeep Vein Thrombosis (DVT): Symptoms, Treatment & Prevention
What are blood clots? What does a blood clot look like?
Blood flows through blood vessels (arteries and veins), and is constantly in motion as the heart pumps blood through arteries to the different areas (organs, glands, cells etc.) of the body. Blood is then returned back to the heart by the veins. Blood returns to the heart by the motion of the body. Muscles squeeze blood through the veins back toward the heart. Without motion, blood has a tendency to stagnate by gravity, which then has the tendency to clot.
Blood clotting is an important mechanism to help the body repair injured blood vessels. Blood consists of
- red blood cells containing hemoglobin that carry oxygen to cells and remove carbon dioxide (the waste product of metabolism),
- white blood cells that fight infection,
- platelets that are part of the clotting process of the body, and
- blood plasma, which contains fluid, chemicals and proteins that are important for bodily functions.
Complex mechanisms exist in the bloodstream to form clots where they are needed. If the lining of the blood vessels becomes damaged, platelets are recruited to the injured area to form an initial plug. These activated platelets release chemicals that start the clotting cascade, using a series of clotting factors produced by the body. Ultimately, fibrin is formed, the protein that crosslinks with itself to form a mesh that makes up the final blood clot.
The medical term for a blood clot is a thrombus (plural=thrombi). When a thrombus is formed as part of a normal repair process of the body, there is little consequence. Unfortunately, there are times when a thrombus (blood clot) will form when it is not needed, and this can have potentially significant consequences. Continue Reading
Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2_suppl):
Dzsheka MS, et al. Stroke and bleeding risk in atrial fibrillation. Clin Cardiol.2014, Oct, 37(10)
Medscape. Deep Vein Thrombosis and Thrombophlebitis.
Fauci, Anthony S., et al. Harrison's Principles of Internal Medicine. 17th ed. United States: McGraw-Hill Professional, 2011.
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