Transient ischemic attack, also known as TIA, is a short-lived, albeit significant neurologic condition that carries significant risk of a full blown stroke in the near future. The word ischemic is a medical term which denotes lack of oxygen to tissues. Ischemia can occur virtually any place in the body. When it involves the heart it is called myocardial ischemia (myocardial means heart muscle). Transient myocardial ischemia often manifest as angina. Prolonged myocardial ischemia results in a heart attack, or myocardial infarction.
Likewise, transient ischemia of brain tissue is referred to as a TIA, while prolonged ischemia to brain tissue results in a cerebral infarction, or a stroke. There are no diagnostic tests which can confirm a TIA, because since the ischemia is transient, it does not cause permanent damage. Therefore CAT scans and MRIs can be completely normal in individuals with TIA, despite the fact that they have significant disease of the blood vessels in the brain. Sometimes, these studies show evidence of blood vessel disease or even evidence of a stroke sometime in the past, which does lead credence to diagnosing recent neurologic symptoms as a TIA.
The diagnosis of TIA is a clinical one. In other words, when a person experiences short-lived neurologic symptoms, such as weakness on one side of the body, facial droop, inability to speak normally, or other symptoms that can be attributed to a specific vascular territory, physicians can often easily make the diagnosis of a TIA, even if the physical examination is completely normal by the time the patient is actually seen.
While the TIA itself does not cause lasting damage, its importance is that individuals who suffer a TIA are at risk of having a stroke in the future. Therefore, it is important to seek medical attention for neurologic symptoms, even if they only last a few minutes. Doing so can help your physician initiate immediately initiate treatment to decrease your risk of having a stroke.
The 2009 American Heart Association and American Stroke Association guidelines for evaluating TIA include considering hospitalizing patients who seek medical attention within 72 hours of having had a TIA and meet certain other criteria. The ABCD squared scoring system can be used to help predict the risk of future stroke. A refers to age; B is for blood pressure; C is for clinical features; D is for diabetes and duration, thus D squared.
If the patient is 60 years of age or older, she gets 1 point for age. If the systolic blood pressure is at least 140 mmHg or the diastolic blood pressure is at least 90 mmHg she gets 1 point for blood pressure. If there is weakness on one side of the body, she gets 2 points for clinical features; if there is a disturbance of speech, but no other neurologic symptoms, she gets 1 point for clinical features. If symptoms last 60+ minutes, she gets 2 points for duration; if symptoms last 10-59 minutes she gets 1 point. Finally, if she has diabetes she gets 1 point for, of course, diabetes. If the total score is at least 3, it is reasonable to admit the patient to the hospital and expedite the diagnostic work up. However, even if the score is 0, hospitalization is still warranted in some instances.
The bottom line is this, stroke is a major killer and a TIA is an early warning sign that you are at higher than normal risk of subsequently having a stroke. If you have new neurologic symptoms, even if short-lived, take them seriously. It may save your life!
The following is a partial list of symptoms that MAY be due to a TIA:
-Weakness of one side of your body or even of a particular body part, such as an arm or leg
-Double or blurred vision
-Difficulty speaking or understanding words
-Fainting, dizziness, unsteadiness, or clumsiness
-Tingling or numbness of one side of your body