Blood clots, or venous thrombosis, are the masses that result when blood coagulates. They occur when a clot forms in the veins and remains there. Your blood flows freely through arteries and veins of all sizes. When the body senses injury or trauma, blood thickens, or clots, and stops flowing at the site of the wound. In this case, when a blood vessel is injured, clotting is vital. However, clot formation inside healthy blood vessels is unusual and potentially fatal. Such clots are frequent complications of venous diseases such as phlebitis.
The size and location of a blood clot determine the threat it poses to the body. If the clot is obstructing a cerebral artery, it can cause stroke. If the clot settles in the coronary arteries, it can cause heart attack. An embolus, or a clot that travels and then becomes lodged in a blood vessel, in a pulmonary artery can cause shortness of breath and even death.
Risk factors for blood clots include:
Prolonged bed rest or immobilization
Recent surgery or trauma
Recent childbirth
Obesity
Use of medications such as birth control pills or estrogen
Atrial Fibrillation
