What is the recommended management for Transient Ischemic Attack (TIA)?

Management of Transient Ischemic Attack (TIA)

All patients with TIA require urgent evaluation within 24-48 hours, immediate antiplatelet therapy, and aggressive risk factor modification to prevent stroke, which occurs in up to 10% of patients within the first week, with half of this risk concentrated in the first 48 hours. 1, 2

Initial Management and Hospitalization

Hospitalize patients with TIA occurring within the past 24-48 hours, crescendo TIAs, symptoms lasting >1 hour, symptomatic carotid stenosis >50%, known cardiac embolic source (atrial fibrillation), or known hypercoagulable state. 1

• For patients managed as outpatients, establish a specialized TIA clinic that can evaluate within 24-48 hours for high-risk patients (ABCD2 score ≥4). 1, 2
• The ABCD2 score stratifies stroke risk based on: Age ≥60 years (1 point), Blood pressure ≥140/90 mmHg (1 point), Clinical features of unilateral weakness (2 points) or speech impairment without weakness (1 point), Duration ≥60 minutes (2 points) or 10-59 minutes (1 point), and Diabetes (1 point). 2
• Educate all patients to return immediately if symptoms recur, as this may represent evolving stroke requiring thrombolytic therapy. 1

Diagnostic Evaluation

Obtain brain imaging (CT or MRI), carotid imaging (duplex ultrasound, CTA, or MRA), ECG, and basic laboratory studies (CBC, electrolytes, renal function, lipids, glucose) urgently in all TIA patients. 1, 2

• Brain MRI is preferred over CT for detecting silent infarcts and determining stroke mechanism. 1, 2
• Carotid duplex ultrasound should be performed urgently; if results are unreliable or discordant with clinical suspicion, proceed to MRA or CTA. 1
• Conventional angiography is reserved for cases where duplex ultrasound and MRA/CTA yield discordant results. 1
• For patients <45 years when other investigations are unrevealing, obtain transthoracic and/or transesophageal echocardiography with bubble study to evaluate for patent foramen ovale and cardiac sources of embolism. 1

Antiplatelet Therapy for Noncardioembolic TIA

Initiate antiplatelet therapy immediately upon TIA diagnosis for all noncardioembolic cases. 1, 3

First-line options (choose one):

• Aspirin 50mg plus extended-release dipyridamole 200mg twice daily is the preferred first-line regimen, as it reduces stroke risk more effectively than aspirin alone without increasing bleeding risk. 1, 3
• Clopidogrel 75mg daily is an appropriate alternative, particularly for patients with peripheral arterial disease or prior MI, and may be slightly more effective than aspirin alone. 1, 3
• Aspirin 50-325mg daily is acceptable when cost or tolerance is a concern, though less effective than combination therapy. 1, 3

Special considerations:

• For patients who experience TIA while already taking aspirin, switch to either clopidogrel 75mg daily OR aspirin 25mg plus extended-release dipyridamole 200mg twice daily. 1
• Do NOT increase aspirin dose in patients who have TIA on aspirin, as higher doses provide no additional benefit but increase bleeding risk. 3, 4
• Do NOT combine aspirin with clopidogrel for long-term therapy, as this combination increases bleeding risk without improving efficacy compared to either agent alone. 3, 5, 6
• Use clopidogrel instead of ticlopidine due to fewer side effects (no neutropenia or thrombotic thrombocytopenic purpura risk) and less monitoring required. 1

Anticoagulation for Cardioembolic TIA

For patients with atrial fibrillation (persistent or paroxysmal) and TIA, initiate oral anticoagulation with target INR 2.5 (range 2.0-3.0). 1, 3

• For mechanical prosthetic heart valves, target INR 3.0 (range 2.5-3.5). 1, 3
• For other cardiac sources including recent MI, mechanical valve, mitral stenosis, intracardiac clot, or severe dilated cardiomyopathy (ejection fraction <20%), use oral anticoagulation with INR 2.0-3.0. 1
• If anticoagulation cannot be administered in atrial fibrillation patients, use aspirin 325mg daily or clopidogrel 75mg if aspirin intolerant. 3
• Do NOT use oral anticoagulation for noncardioembolic TIA, as it provides no benefit over antiplatelet therapy at INR 2.0-3.0 and increases hemorrhagic complications at higher INR ranges. 1, 3

Blood Pressure Management

Start blood pressure-lowering medication 7-14 days after TIA (unless symptomatic hypotension present) with target <140/90 mmHg, or <130/80 mmHg for diabetics. 1, 3, 7

• Use an ACE inhibitor alone or combined with a thiazide diuretic as first-line therapy, or use an angiotensin receptor blocker if ACE inhibitor not tolerated. 1, 3, 7
• This recommendation applies regardless of baseline blood pressure, as blood pressure reduction of approximately 9/4 mmHg benefits even normotensive patients (provided no high-grade carotid stenosis). 1, 7
• For patients with previously treated hypertension, restart antihypertensive medications after the first few days. 7

Lipid Management

Initiate statin therapy immediately for all patients with atherothrombotic TIA, targeting LDL <100 mg/dL, regardless of baseline cholesterol levels. 1, 3

• Prescribe the AHA Step II diet (30% calories from fat, <7% from saturated fat, <200mg/day cholesterol) along with statin therapy. 1
• Maintain ideal body weight and engage in regular physical activity. 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 the following immediately: 1, 3

• Smoking cessation for all smokers (has major and immediate health benefits). 1, 3
• Weight reduction for BMI >25, especially >30. 3
• Regular physical activity at least 10 minutes, 3-4 times weekly. 3
• Sodium restriction. 3

Carotid Endarterectomy

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

• For symptomatic stenosis 50-69%, surgery may be indicated for older men with recent hemispheric symptoms and irregular/ulcerated plaque, but only at experienced centers with complication rates <6%. 1
• Do NOT perform endarterectomy for stenosis <50% by NASCET criteria. 1
• Start aspirin 50-325mg before surgery and continue perioperatively. 1

Critical Pitfalls to Avoid

• Never delay antiplatelet therapy while awaiting diagnostic workup—start immediately upon TIA diagnosis. 3
• Never combine aspirin and clopidogrel long-term after TIA, as bleeding risk outweighs any potential benefit. 3, 5
• Never use hormone replacement therapy for secondary stroke prevention in postmenopausal women, as it may be harmful. 3
• Avoid herbal supplements (feverfew, garlic, ginkgo biloba, ginger, ginseng) in patients on warfarin, as they alter bleeding time; St. John's Wort reduces digoxin levels and enhances warfarin metabolism. 1
• Never assume TIA patients are "low risk"—the 48-hour stroke risk is substantial and demands urgent action. 1, 2