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What Causes Blood Clots?

What Causes Blood Clots

  • Blood clot formation is caused by clumps of blood cells and fibrin strands that happen as a response to blood vessel damage. Their function is to prevent excessive blood loss
  • They are natural and usually dissolve and reabsorb easily but they can become dangerous
  • It’s important to keep any of the coronary arteries, the carotid arteries, the pulmonary artery, the femoral artery in the leg and the abdominal artery free from blockage. If any of those become blocked it can lead to serious injury
  • Risk factors include: laying or sitting for a long period of time (deep vein thrombosis), obesity, physical inactivity, smoking, pregnancy,genetic factors and the prolonged use of birth control


Blood clots (also known as fibrin clots) are clumps of blood cells and fibrin strands that occur as a response to blood vessel damage. The main purpose of a blood clot is to stop a leak in an injured blood vessel. This function protects a person from excessive blood loss. Without the ability to form blood clots, even a minor cut could cause serious medical detriment, even death if enough blood was lost.

Most blood clots dissolve and reabsorb on their own with no problem. The process of forming and then dissolving a blood clot is known as hemostasis.

However, it is possible for blood clots to become dangerous. Sometimes blood clots form in the body even if no injuries are suffered. These dangerous clots might be formed after a surgery or as a response to some trauma (for example, severe internal trauma caused by a car accident). In such situations, these clots can block blood and oxygen flow throughout the body in an artery or vein, which could cause various diseases, a heart attack or the formation of varicose veins.

If a blood clot stops the flow of blood in an artery it is called an arterial thrombosis. If it blocks blood flow in a vein it is called a venous thrombosis. If either an arterial or venous thrombosis loses control and starts to travel through the bloodstream, it is called an embolus.

If any of the following arteries become blocked by blood clots, life-threatening conditions can result. It is important to


• Any of the coronary arteries. These are situated on the heart surface and their main function is to provide oxygen-rich blood to the heart muscle. If any of the coronary arteries become blocked, a heart attack can result. Usually, the coronary arteries become blocked as a response to a plaque rupture (it forms when a plaque deposit on the inner wall of a coronary artery fractures). Common symptoms of such a blockage are chest pain (angina) that usually starts in the chest center, difficulty breathing or shortness of breath, fainting, nausea, or collapse.
• The carotid arteries. These are located in the neck and provide the brain with oxygen-rich blood. If the carotid arteries are blocked by the blood clots, a mini-stroke (transient ischemic attack) or stroke could take place.
• The pulmonary artery. It runs from the heart to the lungs. The condition when this artery becomes blocked is called a pulmonary embolism. The main causes of a pulmonary embolism are damage of the lung (in some cases this can lead to death), peripheral venous disorder in the deep veins of the legs (deep vein thrombosis) and atrial fibrillation (an abnormal heart rhythm).
• The femoral artery in the leg. Symptoms of this blockage are a lack of color in the area and claudication, or cramp-like pains. When left unattended or untreated, it may result in the death of tissue (necrosis) and infection (gangrene).
• Abdominal artery. Its blockage might cause such symptoms as pain, diarrhea and/or vomiting.
Risk factors that increase the chances of blood clot formation include:
• Laying or sitting for long periods of time
• Obesity
• Physical inactivity
• Smoking
• Family and genetic factors
• The prolonged use of contraceptive patches or pills

The information supplied in this article is not to be considered as medical advice and is for educational purposes only.

2 Responses to “What Causes Blood Clots?”

  1. 1
    andrew skillen Says:
    my father is a diabetic injects 2 a day he is a very fit 71 yr old.got encouraged to take coq10 been taking it for 4 weeks now in hospital after suffering a major stroke.he will be in hospital long term possible he will not be able to return home. hope this info can help.regards andrew skillen cockermouth cumbria england.
  2. 2
    Dominic Says:
    Hello Meredith, Several websites, including this one, appear to suggest that CoQ10 inhibits blood clot formation. This statement appears to contradict the claim that CoQ10 is a coagulant or promotes blood clots. For years I was lead into believing that CoQ10 is an ideal alternative product for promoting cardiovascular health, but how good is it if on one hand it (CoQ10) strengthens the heart and on the other hand can cause blood clots that can lead to strokes or heart failure? What is your take on this contradiction with regards to CoQ10? Thanks, Dominic