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

TIA Management Protocol

Patients with suspected TIA presenting within 48 hours with motor weakness or speech disturbance must be sent immediately to an emergency department with advanced stroke care capabilities—this is a medical emergency with up to 10% stroke risk in the first week, and 80% of this risk is preventable with urgent treatment. 1, 2, 3, 4

Immediate Risk Stratification and Disposition

High-Risk Criteria Requiring Immediate ED Referral

• Presentation within 48 hours PLUS unilateral weakness, facial weakness, or speech/language disturbance 1, 2, 3
• ABCD2 score ≥4 (8% stroke risk at 2 days vs 1% for scores <4) 1, 2
• Crescendo TIAs (multiple, increasingly frequent episodes)—these mandate immediate hospitalization under all circumstances 2, 3
• Known symptomatic carotid stenosis >50% 2, 3
• Known cardiac embolic source (atrial fibrillation, mechanical valve, recent MI) 2, 3
• Known hypercoagulable state 2, 3
• Symptom duration >1 hour at presentation 2, 3

The stroke recurrence risk reaches 5% at 2 days and up to 10% in the first week, with half occurring within 48 hours—making time-critical evaluation essential. 2, 3

Time-Critical Diagnostic Workup (Within 24 Hours)

Brain Imaging

• CT or MRI must be completed within 24 hours to exclude hemorrhage, identify acute infarction, and rule out stroke mimics (subdural hematoma, tumor) 5, 1, 3
• MRI with diffusion-weighted imaging is preferred over CT when available, as it detects silent cerebral infarctions in up to 31% of TIA patients and identifies highest-risk individuals 2, 3

Vascular Imaging

• CT angiography from aortic arch to vertex should be performed immediately, ideally at the time of initial brain CT, to assess both extracranial and intracranial circulation 1, 3
• Carotid Doppler ultrasound is essential for anterior circulation symptoms to identify surgically remediable stenosis 5, 1, 3
• Transcranial Doppler provides complementary information on intracranial vessel patency and collateral pathways 5
• If Doppler yields unreliable results and carotid endarterectomy is considered, proceed with MRA or CTA of supraaortic vessels 5
• Conventional angiography is reserved for discordant results between Doppler and MRA/CTA 5

Cardiac Evaluation

• 12-lead ECG immediately upon arrival to identify atrial fibrillation or other cardioembolic sources 5, 1, 3
• Continuous cardiac rhythm monitoring during hospitalization 5, 3
• Transthoracic echocardiography (TTE) when cardioembolic mechanism is suspected 5
• Consider transesophageal echocardiography for patent foramen ovale or atrial sources if TTE is non-diagnostic 5

Laboratory Testing

• Full blood count, serum electrolytes, creatinine 5
• Fasting blood glucose and lipid panel 5, 1
• Additional specialized blood tests only if clinical situation merits (hypercoagulable workup) 5

Hospitalization Strategy

Mandatory Admission Criteria

• High-risk patients (ABCD2 ≥4) should be admitted to a specialized stroke unit for continuous monitoring and rapid treatment initiation 1, 2
• First TIA within past 24-48 hours to facilitate possible thrombolytic therapy if symptoms recur 2
• Acute cerebral infarction on imaging 3
• Large artery atherosclerosis requiring intervention 3
• Cardioembolic source identified 3

Rapid-Access TIA Clinic Alternative

• Only for lower-risk patients who do not meet high-risk criteria above 2, 3
• Must provide evaluation within 24-48 hours with immediate access to neuroimaging, vascular imaging, and stroke specialists 5, 1, 2
• Reduces 90-day stroke risk from 10.3% to 2.1% compared to standard outpatient management 2

Immediate Treatment Based on Etiology

Non-Cardioembolic TIA

• Initiate dual antiplatelet therapy immediately with aspirin plus clopidogrel for 3 weeks, which reduces stroke risk from 7.8% to 5.2% 1
• Start statin therapy immediately regardless of baseline cholesterol 1

Cardioembolic TIA

• Oral anticoagulation for atrial fibrillation, recent MI, mechanical heart valve, mitral stenosis, intracardiac clot, or severe dilated cardiomyopathy 5
• For prosthetic heart valves already on adequate anticoagulation, add aspirin 81mg/day 5
• For patent foramen ovale, use antiplatelet therapy if anticoagulation not indicated 5

Symptomatic Carotid Stenosis

• Carotid endarterectomy for 70-99% stenosis is of overall benefit for symptomatic patients with recent (within 2-4 weeks) hemispheric, nondisabling events 5
• Surgery may be indicated for 50-69% stenosis in select patients (older men with recent hemispheric symptoms and irregular/ulcerated plaque), but only at centers with perioperative complication rate <6% 5
• Perform surgery within 2 weeks of TIA once patient is medically stable 5
• Carotid endarterectomy is NOT recommended for stenosis <50% 5
• Patients undergoing endarterectomy should receive aspirin 50-325mg beginning before surgery 5

Secondary Prevention and Risk Factor Modification

Blood Pressure Management

• Target <130/80 mmHg 1

Diabetes Management

• HbA1c target <7% 1

Follow-Up Arrangements

• Neurology follow-up within 2 weeks with clear medication instructions including type, dose, frequency, and side effects 1
• Patients managed in outpatient settings must be fully educated about the need to return immediately if symptoms recur 2

Critical Pitfalls to Avoid

• Never discharge patients with crescendo TIAs under any circumstances—these mandate immediate hospitalization 2, 3
• Do not delay referral for high-risk patients presenting within 48 hours with motor/speech symptoms 1, 2
• Do not rely solely on ABCD2 scores for disposition decisions—they supplement but do not replace comprehensive evaluation 3
• Do not attempt outpatient workup for patients with known high-risk features (symptomatic carotid stenosis >50%, atrial fibrillation, hypercoagulable state) 2
• Do not delay carotid imaging in anterior circulation TIAs, as urgent revascularization may be needed 3
• Never discharge without confirming outpatient follow-up arrangements 3
• Inquire about herbal medicines (feverfew, garlic, ginkgo biloba, ginger, ginseng) that may alter bleeding time and interact with warfarin; St John's Wort reduces digoxin levels and enhances warfarin metabolism 5