A transient ischemic attack (TIA) occurs when the blood flow to the brain stops for a brief period of time. A TIA is a stroke-like event caused by improper blood flow in the carotid artery. The carotid artery is located in the neck and it carries blood from the heart to the brain. When blood flow is disrupted or blocked within these arteries, stroke-like symptoms may occur. Symptoms of a TIA are similar to those of a stroke, but they do not last as long, as the blockage within the artery may break-up or dissolve. In some individuals, a transient ischemic attack may be a warning sign that a stroke may occur in the future.
Causes of Transient Ischemic Attack
A TIA may be the result of a build-up of plaque that hardens the artery, a condition called atherosclerosis. This plaque build-up can decrease the blood flow through the artery or cause a clot to develop. Risk factors for a transient ischemic attack may include:
- High blood pressure
- High Cholesterol
- Family history
- Cardiovascular disease
Individuals over the age of 55 and people of African-American descent are more at risk for a TIA.
Symptoms of Transient Ischemic Attack
During a transient ischemic attack individuals may experience dizziness and confusion, as well as the following symptoms that may occur suddenly:
- Loss of control on one side of the body
- Drooping of the face
- Loss of vision in one or both eyes
- Slurring of speech
These symptoms are often temporary and usually disappear within an hour. Individuals should seek medical attention after experiencing a TIA, as treatment may help to prevent a future stroke.
Diagnosis of Transient Ischemic Attack
A TIA is often diagnosed after a review of symptoms and a physical examination. Blood tests are performed to check for any underlying conditions and additional tests may include:
- CT scan
- MRI scan
- Transthoracic echocardiogram
In addition to diagnosing a TIA, these tests are used to determine the risk of stroke.
Treatment for Transient Ischemic Attack
Depending on the cause of the TIA, medication may be prescribed to reduce the chance of a blood clot and the risk of stroke. Medication may include blood thinners such as anticoagulants or anti-platelet drugs. In severe cases, surgery may be performed to clear a blockage in the carotid artery and restore blood flow to the brain. Carotid surgery procedures may include endarterectomy or an angioplasty with stent placement.
An endarterectomy surgically removes diseased material and clogged deposits from the inside of an artery to restore normal blood flow. When the procedure is performed on the carotid artery, it is called a carotid endarterectomy. By keeping blood flow open to the brain, a carotid endarterectomy helps prevent the occurrence or recurrence of a TIA or stroke.
Carotid Stenting and Angioplasty
Carotid stenting is the implantation of a metal mesh tube (stent) to hold a clogged artery open so blood can flow through it unobstructed. The stent is put in place using a technique called balloon angioplasty. A small tube known as a catheter with a tiny balloon on the end is inserted into an artery in the groin, snaked up to the carotid artery, and gently expanded, pushing open the blockage and restoring blood flow. The stent is then put in place to ensure that the artery stays open.
Stenting is usually recommended for patients with severe stenosis (blockage) who experience symptoms from the restricted blood flow.