Thrombosis occurs when clots obstruct or block veins (blood vessels that carry blood from the body back into the heart) or arteries (blood vessels that carry oxygenated blood away from the heart to the body). Venous thrombosis is when the blood clot obstructs a vein, and arterial thrombosis is when the blood clot obstructs an artery.
Venous thrombosis may be the result of the following:
Disease or injury to the veins in the legs
Immobility for any reason
Inherited disorders or inherited predisposition
Autoimmune disorders that predispose to clotting
Medications, such as certain contraceptives, that increase the risk of clotting
Pooling (stasis) of blood in the legs and subsequent clotting can result in varicose veins. Clots in the legs may break loose and travel to the lungs, causing pulmonary clots that can result in respiratory distress, pain, and in extreme cases, death.
Arterial thrombosis may be the result of arteriosclerosis, which involves hardening of the arteries where fatty or calcium deposits cause the arterial walls to thicken. This can lead to plaque instability and risk for rupture followed by thrombus.
When arterial thrombosis occurs in the coronary arteries (arteries that branch from the aorta to provide blood to the heart muscle), it can lead to heart attacks. When arterial thrombosis occurs in the cerebral (brain) circulation, it can lead to strokes or lack of oxygen to other organs.
Risk factors for arterial thrombosis may include:
High blood pressure
Lack of activity and obesity
Family history of arterial thrombosis
The following are the most common symptoms of thrombosis. However, each individual may experience symptoms differently. Symptoms may include:
Pain isolated to one leg (usually the calf or inner thigh)
Swelling in the extremity
Numbness or weakness on one side of the body
Acute mental status changes
The symptoms of thrombosis may resemble other blood disorders or medical problems. Always consult your doctor for a diagnosis.
In addition to a complete medical history and physical examination, diagnostic procedures for thrombosis may include venous and arterial ultrasounds and blood tests including hypercoagulability panels. Dye injection with angiography and catheterization may also be used, as well as MRI/MRA and CT. The diagnostic procedure advised depends on the type of thrombus--venous or arterial--and the location.
Specific treatment for thrombosis will be determined by your doctor based on:
Your age, overall health, and medical history
Extent and type of thrombosis
Your tolerance for specific medications, procedures, or therapies
Expectations for the course of the disease
Your opinion or preference
Treatment may include:
Anticoagulant medications, such as coumadin and heparin
Catheters (to expand the width, or lumen, of involved vessels)
Medications, such as antiplatelets, tissue plasminogen activator (t-PA), and/or enzymes, such as streptokinase (to dissolve clots)
Other treatments may be advised in your particular situation and will be reviewed in detail with you by your doctor.