Blood flows through the body via a network of blood vessels made up of arteries and veins. Arteries carry oxygen-rich blood from the heart to our organs and muscles, making it possible for them to function properly. Veins bring blood and carbon dioxide back towards the lungs, helping rid the body of "waste" while replenishing its supply of oxygen. Occasionally, these blood vessels sustain damage and bleed a little. When this occurs, platelets and certain blood proteins take action, forming a clot to stop the flow of blood and repair the vessel.
On occasion, the "repair" process is triggered even though the blood vessels are intact. This results in the formation of clots on the venous and arterial walls, even if there are no lesions, blocking the flow of blood through the blood vessel. This is known as thrombosis.
Thrombosis is a general term that refers to a partially or totally obstructed blood vessel, be it in a vein or an artery. When the problem occurs in a vein, it is generally referred to as thrombophlebitis. Veins in the calves and thighs are most commonly affected. There are two types of thrombophlebitis:
- Superficial thrombophlebitis: as its name indicates, it affects the smaller veins near the skin surface and is not very serious. It can however, be indicative of venous insufficiency and should not be taken too lightly.
- Deep Vein Thrombosis (DVT): affects veins through which significant amounts of blood flow. This increases the risk that a piece of the clot could break off. If this occurs, the clot can block a narrower blood vessel which can, in turn, have serious consequences.
Thrombosis can also cause what is known as an embolism. An embolism is the sudden obstruction of a blood vessel, most often an artery, by a clot that has been brought to the site through the bloodstream. Deep vein thrombosis can cause a pulmonary embolism while arterial thrombosis can cause a cerebral embolism (also known as a CVA or stroke).
When we speak about thrombosis, it is difficult to pinpoint an exact cause since risk factors play an important role:
Symptoms vary depending on the problem.
|Thrombosis||Thrombophlebitis and DVT||Embolism|
|Thrombosis, which begins with numbness, is something that occurs gradually. The area that is no longer being supplied blood may be tender and lacking any pulse.||The symptoms of thrombophlebitis are similar but have a different degree of intensity. Pain, swelling, redness and discomfort may occur. However, many cases are symptom-free and are only diagnosed when and if complications arise.||An embolism is sudden and painful as soon as it occurs. There is no pulse at the site where there is no longer any blood flow.|
Thrombosis and thrombophlebitis must be diagnosed by a physician. An ultrasound of the veins or arteries in question may be required to make a clear diagnosis. In the event of an embolism, it is important to get to the hospital as quickly as possible as it may lower your chances of suffering after-effects.
Thrombosis and thrombophlebitis are generally treated with blood thinners that prevent clotting (ex. CoumadinTM). These treatments require constant and on-going medical monitoring. It is also recommended that compression stockings be worn to prevent clots from forming in the legs.