What are the UK guidelines for managing a patient after a Transient Ischaemic Attack (TIA)?

UK Guidelines for Managing Transient Ischaemic Attack (TIA)

Immediate Risk Assessment and Disposition

All patients presenting within 48 hours of suspected TIA with motor weakness, speech disturbance, or other focal neurological symptoms must be sent immediately to an emergency department with advanced stroke care capabilities. 1

The stroke recurrence risk is highest in the first 48 hours, with rates of 1.5% at 2 days and 2.1% at 7 days when patients receive specialized stroke center care. 2 Without urgent treatment, population-based studies demonstrate stroke risk as high as 11% at 7 days. 1

High-Risk Features Requiring Immediate ED Referral:

• Unilateral weakness affecting face, arm, and/or leg 1
• Speech or language disturbance 1
• Presentation within 48 hours of symptom onset 1
• ABCD2 score ≥4 (8% stroke risk at 2 days vs 1% for scores <4) 3
• Crescendo TIAs (multiple, increasingly frequent episodes) 1
• Known symptomatic carotid stenosis >50% 1
• Known atrial fibrillation or cardiac embolic source 1
• Known hypercoagulable state 1

Time-Critical Diagnostic Workup (Within 24 Hours)

Essential Investigations:

• Brain imaging (CT or MRI) within 24 hours to exclude hemorrhage, identify acute infarction, and rule out stroke mimics 1, 3
• Vascular imaging (carotid Doppler ultrasound for anterior circulation symptoms, or CTA/MRA from aortic arch to vertex) within 24 hours 1, 3
• Electrocardiogram without delay 1
• Basic laboratory work: CBC, electrolytes, creatinine, glucose, and lipid panel 1

Advanced Imaging Considerations:

MRI with diffusion-weighted imaging (DWI) detects silent cerebral infarctions in up to 31% of TIA patients, identifying the highest-risk individuals who require more aggressive management. 1 Positive DWI findings indicate substantially higher stroke recurrence risk. 1

Immediate Treatment Initiation

For Non-Cardioembolic TIA:

Dual antiplatelet therapy with aspirin plus clopidogrel should be initiated immediately for 3 weeks, which reduces stroke risk from 7.8% to 5.2%. 3 This represents an 80% relative risk reduction in subsequent stroke when combined with rapid assessment and aggressive secondary prevention. 2, 1

For Cardioembolic TIA:

Anticoagulation must be initiated for patients with atrial fibrillation or other cardiac embolic sources. 1

For Symptomatic Carotid Stenosis:

Urgent carotid endarterectomy (within 2 weeks of symptom onset) is required for symptomatic carotid stenosis >70%, which significantly reduces stroke risk. 3 Even stenosis >50% warrants urgent vascular surgery consultation. 1

Hospitalization Strategy

Mandatory Admission Criteria:

• First TIA within the past 24-48 hours to facilitate possible early deployment of thrombolytic therapy if symptoms recur 1
• ABCD2 score ≥4 requiring specialized stroke unit admission 3
• Duration of symptoms longer than 1 hour 1
• Crescendo TIAs 1
• Symptomatic internal carotid stenosis >50% 1
• Known cardiac source of embolus 1
• Known hypercoagulable state 1

Rapid-Access TIA Clinic Alternative

If immediate ED referral is not feasible for lower-risk patients only (ABCD2 <4, presenting beyond 48 hours, no high-risk features), a certified rapid-access TIA clinic can evaluate patients within 24-48 hours with immediate access to neuroimaging, vascular imaging, and stroke specialists. 1, 3 However, this is not appropriate for high-risk patients meeting the criteria above. 1

Studies from specialized TIA clinics demonstrate that 82% of patients can be assessed within 24 hours and 93% within 48 hours, with only 28.7% requiring hospital admission and a 3-month stroke recurrence rate of 3.55%. 4

Aggressive Risk Factor Modification

• Blood pressure target <130/80 mmHg 3
• Statin therapy regardless of baseline cholesterol 3
• Diabetes management with HbA1c <7% 3
• Neurology follow-up within 2 weeks with clear medication instructions 3

Critical Pitfalls to Avoid

Do not attempt outpatient workup for patients with crescendo TIAs, known high-risk features (symptomatic carotid stenosis >50%, atrial fibrillation, hypercoagulable state), or ABCD2 score ≥4. 1 These patients require immediate hospitalization, not clinic referral. 1

Do not delay referral based on symptom resolution—the diagnosis of TIA is made based on the history of transient focal neurological symptoms, and complete resolution does not reduce the urgency of evaluation. 5, 6

Do not underestimate transient monocular vision loss (amaurosis fugax), which represents retinal ischemia and requires the same urgent evaluation as cerebral TIA. 1

Evidence Supporting Urgent Management

The EXPRESS and SOS-TIA studies revolutionized TIA management by demonstrating that immediate evaluation and treatment in specialized stroke centers reduces 90-day stroke risk by 80%, from historical rates of 10-20% down to 2-3%. 2, 1 A 2017 meta-analysis of post-2007 studies showed pooled stroke risks of only 1.36% at 2 days, 2.06% at 7 days, 2.78% at 30 days, and 3.42% at 90 days with urgent specialized care. 2