What is the appropriate workup and initial management to rule out a transient ischemic attack (TIA)?

TIA Rule Out: Workup and Initial Management

All patients with suspected TIA require immediate brain imaging (CT or MRI), vascular imaging from aortic arch to vertex (CTA or MRA), 12-lead ECG, and basic laboratory workup, with timing determined by stroke recurrence risk stratification. 1

Risk Stratification Determines Urgency

The timing of your workup depends entirely on when symptoms occurred and what symptoms were present:

HIGHEST RISK: Within 48 hours + motor/speech symptoms

• Patients presenting within 48 hours with unilateral weakness (face, arm, leg) OR language/speech disturbance face an 8% stroke risk at 2 days 2, 3
• These patients require comprehensive evaluation within 24 hours of first healthcare contact 1
• Approximately 50% of recurrent strokes occur within the first 48 hours 2, 4

MODERATE RISK: Within 48 hours to 2 weeks without motor/speech symptoms

• Patients with hemibody sensory symptoms, monocular vision loss, binocular diplopia, hemifield vision loss, dysarthria, dysphagia, or ataxia 1
• Evaluation should occur within 2 weeks of first healthcare contact 1

LOWER RISK: More than 2 weeks from symptom onset

• Evaluation within one month is acceptable 1

Mandatory Initial Workup Components

Brain Imaging (Complete within timeframe based on risk)

• Non-contrast CT head is essential first to exclude hemorrhage (contraindication to antiplatelets/anticoagulation) and identify early ischemic changes 1
• MRI with diffusion-weighted imaging is superior when available—77% sensitivity within 3 hours versus only 16% for CT, and detects silent infarctions in 31% of TIA patients 2
• Brain imaging must be completed within 24 hours for high-risk patients 1

Vascular Imaging (Complete within same timeframe as brain imaging)

• CTA from aortic arch to vertex is the ideal single study—can be performed simultaneously with initial brain CT and evaluates both extracranial and intracranial circulation 1
• This identifies symptomatic carotid stenosis requiring urgent revascularization (Level A evidence) 1
• Acceptable alternatives: Carotid ultrasound for extracranial vessels or MRA, based on immediate availability 1
• Critical point: Vascular imaging is mandatory because symptomatic carotid stenosis >70% requires revascularization within 2 weeks to prevent stroke 2, 3

12-Lead ECG (Without delay)

• Perform immediately to detect atrial fibrillation/flutter and evidence of structural heart disease (prior MI, LVH) 1
• ECG monitoring >24 hours is recommended as part of initial workup to detect paroxysmal atrial fibrillation 1

Laboratory Investigations (Initial bloodwork)

• Complete blood count 1
• Electrolytes 1
• Coagulation studies (aPTT, INR) 1
• Renal function (creatinine, eGFR) 1
• Random glucose 1
• Troponin 1

Subsequent Laboratory Tests (Can be outpatient for lower-risk patients)

• Lipid profile (fasting or non-fasting) 1
• HbA1c or 75g oral glucose tolerance test for diabetes screening 1

Critical Decision Points

Who Requires Immediate ED Referral/Hospitalization?

• Any patient within 48 hours of symptom onset with motor weakness or speech disturbance 2, 4
• "Crescendo TIAs" (multiple, increasingly frequent episodes)—these mandate immediate hospitalization, not outpatient management 2, 4
• Patients with ABCD2 score ≥4 (high-risk) 2, 3
• Known symptomatic carotid stenosis >50% 4
• Known cardiac embolic source (atrial fibrillation) 4
• Known hypercoagulable state 4

Rapid-Access TIA Clinic Alternative

• If certified rapid-access TIA clinic exists with 24-48 hour access to neuroimaging, vascular imaging, and stroke specialists, this is acceptable for high-risk patients instead of ED admission 2, 4
• However, this is NOT appropriate for crescendo TIAs or patients with known high-risk features 4

Common Pitfalls to Avoid

Do not delay imaging for "resolved symptoms"—the 90-day stroke risk after TIA ranges from 10-20% without urgent treatment, reduced to 2-3% with rapid assessment and immediate intervention 2, 4

Do not skip vascular imaging—you cannot risk-stratify or plan secondary prevention without knowing if significant carotid stenosis exists 1

Do not use CT perfusion routinely—while it can identify abnormalities in one-third of TIA cases, it does not change acute management and is not recommended for initial assessment 1

Do not order contrast-enhanced CT head alone—there is no evidence supporting this for TIA evaluation 1

Do not perform catheter angiography as initial test—reserve this for secondary evaluation if endovascular therapy is being considered 1

Evidence Quality Note

The Canadian Stroke Best Practice Recommendations 1 and ACR Appropriateness Criteria 1 represent the highest-quality guideline evidence, both updated in 2018 and 2024 respectively. The American Heart Association scientific statement 5 from 2023 confirms stroke risk can be as high as 17.8% at 90 days, with almost half occurring within 2 days. Rapid assessment reduces this risk by 80% 2, making time-sensitive workup completion non-negotiable for high-risk patients.