What is the recommended emergency workup and initial management for a patient with a suspected transient ischemic attack?

TIA Workup: Emergency Evaluation Protocol

All patients with suspected TIA presenting within 48 hours who have unilateral motor weakness (face, arm, or leg), speech disturbance, or aphasia must be sent immediately to an emergency department with stroke center capabilities—this is a medical emergency requiring evaluation within 24 hours. 1, 2

Risk Stratification and Timing

Very High-Risk (Immediate ED Transfer Required)

• Unilateral weakness (face, arm, leg) within 48 hours 1, 2
• Speech/language disturbance within 48 hours 1, 2
• Crescendo TIAs (multiple, increasingly frequent episodes)—never attempt outpatient management 1, 3
• Known symptomatic carotid stenosis >50%—absolute contraindication to outpatient care 1, 3

These patients face a 1.5% stroke risk at 2 days, but without urgent specialized care this rises to 10-11% at 7 days. 1, 2 Half of all post-TIA strokes occur within the first 48 hours. 2

High-Risk (Evaluation Within 24 Hours)

• Presenting 48 hours to 2 weeks after symptom onset with motor or speech symptoms 1, 2
• Symptom duration >1 hour at presentation 4, 3
• Known cardiac embolic source (atrial fibrillation) 4, 3
• Known hypercoagulable state 4, 3

Moderate-Risk (Evaluation Within 2 Weeks)

• Presenting 48 hours to 2 weeks after onset with isolated sensory deficits, monocular vision loss, diplopia, dysarthria, dysphagia, or ataxia without motor/speech involvement 1, 2

Mandatory Diagnostic Workup (Within 24 Hours for High-Risk)

Brain Imaging

CT head non-contrast must be performed immediately to exclude hemorrhage, detect acute infarction, and rule out stroke mimics. 4, 1 MRI with diffusion-weighted imaging is superior—it detects silent cerebral infarction in approximately 31% of TIA patients, identifying the highest-risk individuals—but CT is acceptable if MRI is unavailable. 4, 1

Vascular Imaging

CT angiography from aortic arch to vertex should be obtained immediately, ideally at the time of initial brain CT, to assess both extracranial and intracranial circulation in a single study. 4, 1 This is the preferred first-line approach because it can be performed simultaneously with brain CT and visualizes the entire cerebrovascular tree. 4, 1

Acceptable alternatives when CTA is unavailable or contraindicated: 4, 1

• Carotid duplex ultrasound (for extracranial vessels only)
• MR angiography

Critical pitfall: Do not delay carotid imaging in anterior circulation TIAs—symptomatic carotid stenosis ≥70% requires urgent revascularization within 2 weeks, and the benefit of carotid endarterectomy diminishes rapidly after this window. 1, 2

Cardiac Evaluation

12-lead ECG must be obtained without delay to identify atrial fibrillation, atrial flutter, or evidence of structural heart disease (myocardial infarction, left ventricular hypertrophy). 4, 1

Cardiac monitoring for >24 hours is recommended as part of initial stroke workup to detect paroxysmal atrial fibrillation in patients who would be anticoagulation candidates. 4 For embolic stroke of undetermined source where initial monitoring is negative, prolonged ECG monitoring for at least 2 weeks improves detection of paroxysmal atrial fibrillation. 4

Laboratory Investigations

Initial bloodwork (obtain immediately): 4, 1

• Complete blood count
• Electrolytes
• Coagulation studies (aPTT, INR)
• Renal function (creatinine, eGFR)
• Random glucose or hemoglobin A1c
• Troponin

Subsequent testing (can be outpatient if stable): 4

• Lipid profile (fasting or non-fasting)
• Comprehensive diabetes screening (fasting glucose, 2-hour glucose, HbA1c, or oral glucose tolerance test)

Admission Criteria

Mandatory hospitalization for: 1, 3

• Acute cerebral infarction on imaging
• Large artery atherosclerosis with symptomatic carotid stenosis >50%
• Cardioembolic source requiring anticoagulation
• Crescendo TIAs
• Known hypercoagulable state
• Symptom duration >1 hour at presentation

Safe discharge after 24 hours only if: 1

• Complete diagnostic workup shows no embolic source requiring immediate treatment
• No acute infarction on brain imaging
• No significant carotid stenosis requiring urgent intervention

Evidence-Based Outcomes

Modern rapid-evaluation pathways in specialized stroke centers have reduced 90-day stroke risk from historical rates of 10-20% down to 1.5% at 2 days, 2.1% at 7 days, and 2.8% at 30 days. 1, 2 This represents an 80% relative risk reduction through urgent assessment and treatment. 5, 6

In contrast, patients with multiple vascular risk factors who are not urgently evaluated face stroke risks as high as 36% at 7 days. 1, 2

Special Consideration: Horner Syndrome

Unilateral ptosis with contralateral headache is a red-flag sign for carotid artery dissection, a surgical emergency that can progress to complete stroke within hours. 2 This combination mandates immediate CTA from aortic arch to vertex and inpatient admission. 2

The Rapid-Access TIA Clinic Alternative

If a certified rapid-access TIA clinic with immediate neuroimaging, vascular imaging, and stroke specialist availability exists, lower-risk patients (those not meeting very high or high-risk criteria above) can be evaluated within 24-48 hours rather than through ED admission. 1, 3 However, this option is never appropriate for patients with motor/speech symptoms within 48 hours, crescendo TIAs, or known high-risk features. 1, 3

Critical Pitfalls to Avoid

• Never discharge patients with crescendo TIAs under any circumstances 1, 3
• Do not rely solely on ABCD2 scores for disposition decisions—they supplement but do not replace comprehensive evaluation 1, 7
• Do not attempt outpatient workup for known atrial fibrillation, symptomatic carotid stenosis >50%, or hypercoagulable states 1, 3
• Never discharge without confirming outpatient follow-up arrangements 1