A TIA causes the same symptoms associated with a stroke, such as weakness or numbness on one side of the body, sudden dimming or loss of vision, difficulty speaking or understanding language or slurred speech.
All forms of stroke, including a TIA, result from a disruption in blood flow to the central nervous system.
Recognition that a TIA has occurred is an opportunity to start treatment, including medications and lifestyle changes, to prevent future strokes.
Signs and symptoms of TIA are widely variable and can mimic other neurologic conditions, making the clinical context and physical exam crucial in ruling in or out the diagnosis.
The most common presenting symptoms of TIA are focal neurologic deficits, which can include, but are not limited to:[5] Numbness or weakness generally occur on the opposite side of the body from the affected hemisphere of the brain.
[12][13] Unlike in stroke, the blood flow can become restored prior to infarction which leads to the resolution of neurologic symptoms.
[12] In-situ thrombosis, an obstruction that forms directly in the cerebral vasculature unlike the remote embolism previously mentioned, is another vascular occurrence with possible presentation as TIA.
[12] Also, carotid stenosis secondary to atherosclerosis narrowing the diameter of the lumen and thus limiting blood flow is another common cause of TIA.
[3] Laboratory tests should focus on ruling out metabolic conditions that may mimic TIA (e.g. hypoglycemia), in addition to further evaluating a patient's risk factors for ischemic events.
Other lab tests, such as a full hypercoagulable state workup or serum drug screening, should be considered based on the clinical situation and factors, such as age of the patient and family history.
[8] A fasting lipid panel is also appropriate to thoroughly evaluate the patient's risk for atherosclerotic disease and ischemic events in the future.
[6] An electrocardiogram is necessary to rule out abnormal heart rhythms, such as atrial fibrillation, that can predispose patients to clot formation and embolic events.
[15] Presence of ischemic lesions on diffusion weighted imaging has been correlated with a higher risk of stroke after a TIA.
[17] For this reason, the U.S. Preventive Services Task Force (USPSTF) "recommends against screening for asymptomatic carotid artery stenosis in the general adult population".
[3] Although there is a lack of robust studies demonstrating the efficacy of lifestyle changes in preventing TIA, many medical professionals recommend them.
[23] An exception is TIAs due to blood clots originating from the heart, in which case anticoagulants are generally recommended.
Atrial fibrillation is an abnormal heart rhythm that may cause the formation of blood clots that can travel to the brain, resulting in TIAs or ischemic strokes.
[21] However, combined antiplatelet and anticoagulant therapy may be warranted if the patient has symptomatic coronary artery disease in addition to atrial fibrillation.
If this is thought to be the cause of the TIA, people may be temporarily treated with warfarin or other anticoagulant to decrease the risk of future stroke.
[30] The effects achieved in stroke recurrence were mainly obtained through the ingestion of angiotensin-converting enzyme (ACE) inhibitor or a diuretic.
[31][32][33] While its role in stroke prevention is unclear, statin therapy has been shown to reduce all-cause mortality and may be recommended after TIA.
[36] For people with asymptomatic carotid stenosis, the increased risk of stroke or death during the stenting procedure compared to an endarterectomy is less certain.
[37] Treatment and preventative measures after a TIA (for example treating elevated blood pressure) can reduce the subsequent risk of an ischemic stroke by about 80%.
One limitation of the ABCD² score is that it does not reliably predict the level of carotid artery stenosis, which is a major cause of stroke in TIA patients.
The patient's age is the most reliable risk factor in predicting any level of carotid stenosis in transient ischemic attack.
[38] The ABCD2 score is no longer recommended for triage (to decide between outpatient management versus hospital admission) of those with a suspected TIA due to these limitations.
[6] With the difficulty in diagnosing a TIA due to its nonspecific symptoms of neurologic dysfunction at presentation and a differential including many mimics, the exact incidence of the disease is unclear.