Makindo Medical Notes

Related Subjects: |Neurological History taking |Causes of Stroke |Ischaemic Stroke |Hypertension |Small Vessel Disease |Hypertension

🌟 Introduction

• Transient Ischaemic Attacks (TIAs) are a medical emergency 🚨 — they carry a high risk of disabling or fatal stroke within days.
• Rapid diagnosis and treatment can reduce stroke risk by up to 80%.
• Most TIAs resolve within 1 hour (classic definition allows <24h), but urgent assessment is essential.

🧠 Definition

• A TIA is a transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischaemia, without acute infarction on imaging.
• Diagnosis is primarily clinical, supported by history and rapid imaging.

🩺 Clinical Features

• Carotid Territory: Dysphasia, hemiplegia, hemisensory loss, hemianopia, monocular blindness (amaurosis fugax).
• Vertebrobasilar Territory: Diplopia, dysarthria, ataxia, vertigo, hemiplegia, hemisensory loss, Horner’s syndrome.
• Atypical / Unlikely TIA: Gradual onset, spreading paraesthesia, confusion, blackout, isolated vertigo, seizure activity.

🩻 Establishing the Diagnosis

• Take a clear history: onset, duration, and resolution of symptoms.
• Note posture at onset, preceding triggers (e.g., exertion, dehydration, infection).
• Enquire about migraine, seizures, or similar prior events.
• Check for vascular risk factors: hypertension, AF, diabetes, smoking, hyperlipidaemia.

🔎 Differential Diagnosis

⚡ Immediate Management

• If symptoms are ongoing → treat as stroke and transfer to ED/Hyperacute Stroke Unit (HASU).
• If stable and TIA suspected:
  • Aspirin 300 mg immediately (unless contraindicated, or patient already anticoagulated) 💊
  • Start high-intensity statin (Atorvastatin 80 mg) unless contraindicated.
  • Arrange urgent TIA clinic review within 24 hours (NICE NG128).
  • Advise no driving until reviewed by specialist 🚗❌.

🧪 Investigations

• Blood tests: FBC, U&E, glucose, lipids, ESR (consider GCA if visual symptoms).
• ECG: Check for AF or recent MI.
• Holter Monitoring: For paroxysmal AF if initial ECG normal.
• Brain Imaging: MRI with DWI within 24h (preferred), CT if MRI unavailable.
• Vascular Imaging: Carotid Doppler, CTA or MRA to assess for carotid stenosis.

🏥 Role of the TIA Clinic

💊 Medical Management

• Atherothrombotic TIA: Long-term single antiplatelet therapy (e.g., Clopidogrel 75 mg daily). Aspirin + Dipyridamole if Clopidogrel unsuitable.
• Cardioembolic TIA (AF, valve disease): Anticoagulate with DOAC (e.g., Apixaban, Rivaroxaban, Dabigatran, Edoxaban) or Warfarin.
• Blood Pressure: Target <140/90 mmHg (<130/80 if diabetic).
• Lipids: High-intensity statin regardless of baseline cholesterol.
• Lifestyle: Stop smoking 🚭, weight reduction, healthy diet, regular exercise 🏃‍♂️.

🔪 Surgical Management

• Carotid Endarterectomy: Within 2 weeks of TIA for symptomatic carotid stenosis.
  • 70–99% stenosis → Strongly recommended.
  • 50–69% stenosis → Consider if low surgical risk.
  • <50% stenosis or complete occlusion → Not beneficial.

📊 Prognosis

• Risk of stroke after TIA is highest in the first few days: ~5% at 2 days, ~10% at 90 days.
• Early intervention (antiplatelet, statin, BP control, surgery if indicated) drastically reduces this risk.

📚 References

• NICE NG128: Stroke and TIA in over 16s (2019)
• Johnston SC, Rothwell PM, et al. Lancet. 2007.
• Josephson SA, Sidney S, et al. Stroke. 2008.