A TIA is caused by a temporary blockage of the blood supply to the brain either by a blood clot or fatty material, explains the Merck Manual Home Edition. Other causes include low oxygen levels in the blood, anemia, carbon monoxide poisoning, polycythemia and low blood pressure.
The symptoms of a TIA develop suddenly and last for a few minutes, according to the Mayo Clinic. They include weakness, numbness, and paralysis of an arm, leg or the face. Other symptoms include slurred or garbled speech, difficulty understanding others, blindness in one or both eyes, and loss of coordination.
A TIA is a warning sign of an impending stroke, the Mayo Clinic states. Risk factors include a family history of stroke or TIA, increasing age, male gender, prior ischemic attacks and sickle cell disease. Pre-existing health conditions that increase the risk include hypertension, high cholesterol, cardiovascular disease, carotid artery disease and peripheral artery disease. Others include diabetes, elevated homocysteine levels and excess weight.
A TIA is diagnosed with a physical exam, carotid ultrasonography, computerized tomography, computerized tomography angiography, and magnetic resonance imaging, according to the Mayo Clinic. Others include magnetic resonance angiography, echocardiography and arteriography. TIAs are treated with anti-platelet medications, anticoagulants, surgery and angioplasty. Aspirin, clopidogrel and Aggrenox make platelets less sticky and reduce blood clotting. Heparin, warfarin and dipyridamole decrease coagulation.