a blood clot patient recovers in a hospital bed

Blood Clot Causes

A blood clot, or thrombus, is the coagulation of blood and is achieved by the aggregation of platelets that form a platelet plug. A blood clot is normal in the case of injury, during which it is used to stop the bleeding, but it can be very dangerous, even fatal, under abnormal circumstances.

Technically, a blood clot is the inappropriate triggering of the coagulation process in an uninjured or slightly injured vessel. There are two general categories of blood clots. Superficial phlebitis, or a clot formed in the small veins close to the skin's surface, may result in localized redness, pain and swelling. It this type of blood clot rarely causes complications and requires minimal treatment. Deep vein thrombosis, or a clot formed inside the larger, deeper veins, can cause more severe and widespread symptoms in the affected area, usually the leg, and consequently may cause more serious damage to the body. Clots that break away from a deep vein thrombosis and travel to the lungs may cause a life-threatening clot in the lungs, called pulmonary embolism. A blood clot is a symptom of a larger condition. There are many potential causes of blood clots, and one should work with a healthcare professional for an accurate diagnosis.

Causes of Blood Clots

There are many different causes of blood clots, but the simple clotting process is triggered whenever flowing blood is exposed to thrombogenic substances. The word thrombogenic comes from hrombus, which is another word for blood clot. Many thrombogenic substances exist in the skin or blood vessel walls. These substances are, under normal circumstances, safely separated from flowing blood, and their contact with blood usually means the blood vessel wall has been ruptured and is bleeding. Tissue factor, collagen, and von Willebrand factor are examples of thrombogenic substances. A common cause of blood clots is blood failing to flow properly. Atrial fibrillation is an abnormal hear rhythm in which blood pools in the heart, where a clot may form. If a blood clot dislodges and travels to the brain, it can cause a stroke. Prolonged immobilization can reduce blood flow in the legs, increasing the risk of deep venous thrombosis, or DVT (blood clots in leg veins). Many common conditions and factors may affect blood's flow and clotting process, including a family history of blood clots, heart arrhythmias (atrial fibrillation), medications like oral contraceptives and hormone therapy drugs, pregnancy, prolonged sitting or bed rest and many invasive surgeries.

Risk Factors of the Causes of Blood Clots

The risk factors in the causes of blood clots looks like a long list of already frightening conditions. The circulation of blood through the heart and out to the rest of the body, particularly the brain, is a delicate balance that is susceptible to even the smallest disruptor. A few of those conditions that put an individual at risk for blood clotting are: antiphospholipid syndrome, arteriosclerosis, Buerger's disease, essential thrombocythemia, factor V Leiden, heart attack, heart failure, peripheral artery disease (PAD), polycythemia vera, pulmonary embolism, stroke, thrombocytosis, and thrombophlebitis. Not surprisingly, the heart plays a central role in blood health and the rest of one's body, so certain lifestyle factors that put heart health at risk also increases the risk of blood clots and other conditions. A high cholesterol diet can lead to clogged arteries and the slowing of blood flow. Inactivity reduces circulation. Those who spend a lot of time traveling for work, either by airplane or car, may spend many hours a week sitting. Obesity makes it more difficult for the blood to flow and consequently forces the heart to work harder, which can lead to many conditions including blood clots. Undergoing surgery for a completely unrelated condition increases the risk of blood clots as well.

Last Updated: November 17, 2016