What is the diagnosis for a Transient Ischemic Attack (TIA)?

From the Guidelines

Patients with suspected Transient Ischemic Attack (TIA) should undergo immediate evaluation with neuroimaging and vascular studies, and be hospitalized or undergo expedited outpatient evaluation within 24-48 hours, as the risk of subsequent stroke is highest in the first few days after a TIA.

Key Evaluation Components

• Neuroimaging: CT or MRI brain imaging to rule out hemorrhage or infarction, with MRI with diffusion-weighted imaging preferred for detecting small infarcts 1
• Vascular imaging: carotid ultrasound, CT angiography, or MR angiography to identify potential stenosis
• Laboratory tests: complete blood count, coagulation studies, lipid panel, and glucose levels
• Electrocardiogram and cardiac monitoring for at least 24 hours to detect atrial fibrillation

Risk Stratification

• The ABCD² score (Age, Blood pressure, Clinical features, Duration, Diabetes) helps stratify stroke risk after TIA, with higher scores associated with a higher risk of stroke 1

Management

• Prompt evaluation and management of TIA can help prevent subsequent stroke, and proper diagnosis allows for appropriate preventive treatment including antiplatelet therapy, statins, and management of underlying risk factors such as hypertension and diabetes 1
• A local admissions policy should be developed by hospitals and representative physicians to set out the categories of patients who will usually be referred or admitted to the hospital 1
• Hospitals and general practitioners should agree on a local admissions policy and a local protocol for referral to specialist assessment clinics for patients with TIA who do not require hospital admission 1

From the Research

TIA Diagnosis and Management

• TIA is associated with a high risk of subsequent stroke, with up to a 10% risk of stroke within 7 days and a 25% risk of death at 1 year 2
• The diagnosis and management of TIA involve the use of antiplatelet therapy, with aspirin being the most commonly prescribed agent 3
• Dual antiplatelet therapy with aspirin and clopidogrel is recommended for patients with high-risk TIA, with a reduction in stroke risk from 7.8% to 5.2% 4

Antiplatelet Therapy

• Antiplatelet therapy can result in significant reductions in secondary stroke risk, with a study showing that nearly 50% of patients with TIA leave the Emergency Department without any medication 2
• Aspirin is the most commonly prescribed antiplatelet agent, with low-dose aspirin being the most frequently used agent for antiplatelet-naive patients 3
• The use of clopidogrel is also recommended, with a study showing that dual antiplatelet therapy with aspirin and clopidogrel reduces stroke risk in select patients with high-risk TIA and minor stroke 4

Comparison of Antiplatelet Agents

• A mixed treatment comparison meta-analysis found that warfarin and the new anticoagulants (apixaban, dabigatran, edoxaban, and rivaroxaban) are similar in the reduction of stroke, vascular death, and mortality, with the exception of one comparison where warfarin was associated with more non-major bleeding than apixaban 5
• A study found that dabigatran is more effective than warfarin in ischemic stroke prevention, particularly in patients with a history of stroke or TIA 6

Treatment Guidelines

• Patients presenting with nondisabling AIS or high-risk TIA should receive dual antiplatelet therapy with aspirin and clopidogrel within 24 hours of presentation 4
• Patients with symptomatic carotid stenosis should receive carotid revascularization and single antiplatelet therapy, and those with atrial fibrillation should receive anticoagulation 4