What is the recommended management for a patient who has experienced a Transient Ischemic Attack (TIA)?

Management of Transient Ischemic Attack (TIA)

All patients with TIA require immediate antiplatelet therapy and urgent evaluation within 24-48 hours to prevent stroke, as the highest risk period is within the first few days after symptom onset. 1

Immediate Actions and Risk Stratification

Start antiplatelet therapy immediately upon TIA diagnosis—never delay while awaiting diagnostic workup. 1 The urgency stems from the extremely high early stroke risk, particularly in the first 48-72 hours. 2

Hospitalization Criteria

Admit patients with any of the following high-risk features: 1

• TIA within the past 24-48 hours
• Crescendo TIAs (multiple episodes)
• Symptoms lasting >1 hour
• Symptomatic carotid stenosis >50%
• Known cardiac embolic source (atrial fibrillation)
• Known hypercoagulable state

ABCD2 Score for Risk Stratification

Calculate the ABCD2 score to identify high-risk patients (score ≥4): 1

• Age ≥60 years: 1 point
• Blood pressure ≥140/90 mmHg: 1 point
• Clinical features: unilateral weakness (2 points) OR speech impairment without weakness (1 point)
• Duration: ≥60 minutes (2 points) OR 10-59 minutes (1 point)
• Diabetes: 1 point

Patients with ABCD2 ≥4 require evaluation within 24-48 hours, preferably in a specialized TIA clinic. 1

Urgent Diagnostic Workup

Obtain the following studies urgently in all TIA patients: 1

• Brain imaging: MRI preferred over CT (detects silent infarcts and determines stroke mechanism better) 1
• Carotid imaging: Duplex ultrasound first-line; if unreliable or discordant, proceed to MRA or CTA 3, 1
• ECG: To detect atrial fibrillation
• Laboratory studies: CBC, electrolytes, renal function, lipid panel, glucose 1
• Echocardiography: TTE and/or TEE with right-to-left shunt testing in patients <45 years when other investigations are unrevealing 3

Antiplatelet Therapy for Noncardioembolic TIA

High-Risk Patients (ABCD2 ≥4, symptom onset within 24 hours, or minor stroke)

Initiate dual antiplatelet therapy with aspirin plus clopidogrel for 21-30 days, then transition to monotherapy. 4, 5

Loading dose protocol: 5

• Clopidogrel 300-600 mg on day 1
• Aspirin 160-325 mg on day 1

Maintenance for 21-30 days: 4, 5

• Clopidogrel 75 mg daily
• Aspirin 75-325 mg daily

This approach prevents 15 ischemic strokes per 1,000 patients treated but causes 5 major hemorrhages per 1,000 patients. 4 The benefit-to-risk ratio is favorable only for the first 21-30 days; never continue dual antiplatelet therapy beyond this period as bleeding risk outweighs benefit. 1, 5, 6

Long-Term Monotherapy (after 21-30 days or for lower-risk patients)

Choose one of the following regimens for indefinite secondary prevention: 3, 1, 4

First-line options (in order of preference):

1. Aspirin 50 mg + extended-release dipyridamole 200 mg twice daily (most effective, reduces stroke risk more than aspirin alone without increasing bleeding) 3, 1
2. Clopidogrel 75 mg daily (slightly more effective than aspirin alone, particularly for patients with peripheral arterial disease or prior MI) 3, 1, 5
3. Aspirin 75-325 mg daily (effective baseline option; use lowest effective dose to minimize bleeding risk) 3, 7, 8

The aspirin-dipyridamole combination is preferred as first-line therapy based on superior efficacy. 1 Clopidogrel is an excellent alternative, especially for aspirin-intolerant patients or those with concurrent peripheral vascular disease. 5, 7

Critical pitfall: Headache occurs commonly with dipyridamole but typically resolves within days; counsel patients to "push through" this side effect rather than discontinuing therapy. 7 Consider temporary dose reduction if headache is intolerable.

Anticoagulation for Cardioembolic TIA

For patients with atrial fibrillation (persistent or paroxysmal), oral anticoagulation is superior to antiplatelet therapy and must be initiated. 3, 1, 4, 9

Anticoagulation regimens:

• Target INR 2.5 (range 2.0-3.0) for nonvalvular atrial fibrillation 3, 1
• Target INR 3.0 (range 2.5-3.5) for mechanical prosthetic heart valves 1
• Direct oral anticoagulants (apixaban, dabigatran, rivaroxaban) are alternatives to warfarin 4, 9

If the patient is already on clopidogrel when cardioembolic TIA is diagnosed, stop clopidogrel and switch to anticoagulation. 4 Use aspirin 325 mg daily or clopidogrel 75 mg daily only if anticoagulation is contraindicated. 3, 5

Other cardiac sources requiring anticoagulation: 3

• Recent myocardial infarction
• Mechanical heart valve prosthesis
• Mitral stenosis
• Intracardiac clot
• Severe dilated cardiomyopathy (ejection fraction ≤20%)

Do not use anticoagulation for noncardioembolic TIA—no benefit over antiplatelet therapy and higher hemorrhagic risk. 3

Blood Pressure Management

Start antihypertensive therapy 7-14 days after TIA (unless symptomatic hypotension present). 1

Target blood pressure: 1

• <140/90 mmHg for most patients
• <130/80 mmHg for diabetics

First-line agents: 1

• ACE inhibitor alone OR
• ACE inhibitor + thiazide diuretic OR
• Angiotensin receptor blocker (if ACE inhibitor not tolerated)

Lipid Management

Initiate high-intensity statin therapy immediately for all patients with atherothrombotic TIA, regardless of baseline cholesterol levels. 1

• Target LDL <100 mg/dL 1
• Prescribe AHA Step II diet (≤30% calories from fat, <7% from saturated fat, <200 mg/day cholesterol) 1

Diabetes Management

Target fasting blood glucose <126 mg/dL (7 mmol/L) using diet, regular exercise (at least 3 times weekly), and oral hypoglycemics or insulin as needed. 1

Lifestyle Modifications

Counsel all patients on: 1

• Smoking cessation (mandatory)
• Weight reduction for BMI >25
• Regular physical activity (at least 10 minutes, 3-4 times weekly)
• Sodium restriction

Carotid Revascularization

For symptomatic carotid stenosis 70-99%, perform carotid endarterectomy within 2 weeks at centers with perioperative complication rates <6%. 1

For symptomatic stenosis 50-69%, surgery may be indicated for: 1

• Older men
• Recent hemispheric symptoms
• Irregular/ulcerated plaque
• Only at experienced centers with complication rates <6%

Critical Contraindications and Warnings

Absolute contraindications to dual antiplatelet therapy: 5

• Severe uncontrolled hypertension
• Known allergies to aspirin or clopidogrel
• Hemophilia or bleeding disorders
• Active major bleeding

Assess gastrointestinal bleeding risk before initiating antiplatelet therapy; educate high-risk patients on signs and symptoms of bleeding to facilitate prompt treatment. 7

Educate all patients to return immediately if symptoms recur, as this may represent evolving stroke requiring thrombolytic therapy. 1