From the Guidelines
Patients who have experienced a Transient Ischaemic Attack (TIA) should undergo prompt and comprehensive investigations, including brain imaging with either CT or MRI, vascular imaging of the carotid arteries, cardiac evaluation with 12-lead ECG, and blood tests, to identify the cause and prevent future strokes, as recommended by the most recent guidelines 1.
Recommended Investigations
The following investigations are recommended for patients with suspected TIA:
- Brain imaging with either CT or MRI, preferably within 24 hours of symptom onset, with MRI being more sensitive for detecting small infarcts
- Vascular imaging of the carotid arteries using carotid ultrasound, CT angiography, or MR angiography to identify significant stenosis that may require intervention
- Cardiac evaluation with 12-lead ECG for all patients and consideration of echocardiography to detect cardiac sources of emboli
- Blood tests, including complete blood count, electrolytes, renal function, lipid profile, glucose, HbA1c, and coagulation studies
Timing of Investigations
Rapid assessment and investigation, ideally within 24-48 hours of symptom onset, is crucial as the risk of subsequent stroke is highest in the days immediately following a TIA 1.
Secondary Prevention Strategies
These investigations help determine the etiology of the TIA, which guides appropriate secondary prevention strategies, such as:
- Antiplatelet therapy (typically aspirin 75-325mg daily, clopidogrel 75mg daily, or combination therapy depending on risk factors)
- Anticoagulation if atrial fibrillation is detected (with agents like apixaban 5mg twice daily or warfarin with target INR 2-3)
- Management of modifiable risk factors, including hypertension, diabetes, and hyperlipidemia 1.
From the Research
Investigations for Transient Ischaemic Attack (TIA)
The following investigations are recommended for patients who have experienced a TIA:
- Early brain imaging 2, 3, 4
- Electrocardiogram (ECG) 2, 3
- Carotid imaging in patients with anterior circulation symptoms 2, 3
- Total blood count 3
- Noninvasive carotid testing, usually by carotid duplex ultrasonography, for patients with anterior circulation symptoms 3
- Magnetic resonance angiography (MRA) or a conventional arteriogram for patients with posterior circulation TIAs 3
- CT, CT angiography, carotid Doppler ultrasound, and MRI for imaging of the brain and intracranial and extracranial blood vessels 4
Additional Considerations
Other testing depends on the presumptive etiology of the TIA 3 Conditions which mimic TIAs need to be considered and ruled out, such as Todd's transient paralysis, migraine auras, space-occupying lesions, arteriovenous malfunction, and peripheral nerve disease 3 Antiplatelet therapy, such as aspirin, clopidogrel, or the combination of aspirin and extended-release dipyridamole, is recommended for patients with TIA 5, 4 Vascular risk factor reduction strategies are also important for preventing future strokes 4