Cardioembolic stroke

Related Subjects: |Acute Stroke Assessment (ROSIER&NIHSS) |Atrial Fibrillation |Atrial Myxoma |Causes of Stroke |Ischaemic Stroke |Cancer and Stroke |Cardioembolic stroke |CT Basics for Stroke |Endocarditis and Stroke |Haemorrhagic Stroke |Stroke Thrombolysis |Hyperacute Stroke Care

🧠 Introduction

Cardioembolic stroke = cerebral ischaemia from emboli arising in the 💓 heart (atria, ventricles, valves) that travel to cerebral arteries. 🔄 Also includes paradoxical emboli via PFO/ASD. 📊 They account for 15–30% of all ischaemic strokes, with mortality up to 30%. ⚡ In those >80y, >20% of strokes are AF-related → major prevention opportunity with anticoagulation.

💥 Causes & Sources

• High Risk Sources:
  • 🫀 Atrial fibrillation (AF): Valvular & non-valvular; risk stratified by CHA₂DS₂-VASc.
  • ❤️ Recent MI: esp. LV aneurysm/hypokinesia.
  • ⚙️ Mechanical valves: very thrombogenic.
  • 🫁 Dilated cardiomyopathy: chamber stasis → thrombus.
  • 🫀 Rheumatic mitral stenosis: atrial enlargement + stasis.
• Other Sources:
  • 🦠 Infective endocarditis: septic vegetations embolise.
  • 🎗 Atrial myxoma: fragments embolise.
  • 🔄 PFO: paradoxical embolus from venous system.
  • 💓 LAA thrombus: classic in AF.
  • 🪨 Mitral prolapse/calcification: thrombogenic.
  • 🧬 Marantic endocarditis: malignancy, SLE.

📚 Classification

• 🏛 Cardiac wall/chamber: cardiomyopathies, LV aneurysm, atrial septal aneurysm, myxoma, fibroelastomas, thrombi, septal defects (PFO/ASD).
• 🫀 Valvular disease: RHD, prosthetic valves, infective or Libman–Sacks endocarditis, MVP, annular calcification.
• ⚡ Arrhythmias: AF, flutter, sick sinus syndrome.

🩺 Clinical Features

• ⚡ Sudden onset, deficits maximal at onset.
• 🌍 Multiple territories can be affected.
• ↕️ Fluctuating symptoms if embolus fragments.
• 🛑 Large vessel occlusion: MCA, ICA, PCA.
• 🩸 High risk of haemorrhagic transformation.
• 🧑‍⚕️ May present with ↓ consciousness, seizures at onset.

🔑 Look for cardiac signs: irregular pulse (AF), murmurs, heart failure, IE stigmata.

📊 Causes & Frequency

• AF (non-valvular): ~50% → stroke risk ↑3–5x.
• Recent MI: ~10% → esp. anterior MI, early weeks.
• LV thrombus: ~10% → echo for detection.
• Rheumatic MS: ~10% → very high embolic risk.
• Mechanical valves: ~5% → lifelong warfarin.
• Other (tumours, IE, PFO): ~15%.

🏗 Structural Heart Disease

• 💔 Cardiomyopathy (dilated, hypertrophic, restrictive).
• 🦠 Infective endocarditis.
• 🎗 Atrial myxoma (constitutional + embolic signs).
• 🩸 LV aneurysm post-MI.
• 🪨 Mitral valve prolapse/calcification.
• 🔄 PFO in cryptogenic stroke (younger pts).

🧪 Investigations

• 🩸 Bloods: FBC, coagulation, ESR, cultures (if IE suspected).
• 📉 ECG: AF, MI changes.
• 📡 Holter: detect paroxysmal AF.
• 🖼 CT/MRI brain: multiple embolic infarcts, DWI sensitive.
• 🧲 CTA/MRA: vessel occlusions.
• 🫀 Echo:
  • TTE: chamber size, LV function.
  • TEE: LAA thrombus, vegetations, PFO (with bubble study).
• 🧠 TCD: detect microemboli, shunts.

⚕️ Management

• 🚨 Acute stroke protocols: reperfusion therapy (IVT/thrombectomy) as per guidelines.
• 💊 Anticoagulation:
  • DOACs (apixaban, rivaroxaban, dabigatran, edoxaban) for non-valvular AF.
  • Warfarin for mechanical valves & rheumatic MS (DOACs not licensed).
  • Timing: start 4–14d post-stroke depending on size/bleed risk.
• ❤️ Underlying cardiac care: heart failure optimisation, valve surgery, tumour excision if relevant.
• 🛡 Risk factor control: BP, DM, statins, smoking cessation.
• 🤝 Team approach: neuro + cardiology + stroke rehab.

📈 Prognosis

• ⬆️ More severe strokes (large artery occlusion).
• ⚰️ Higher early mortality vs other stroke subtypes.
• 🔄 High recurrence risk if no anticoagulation.
• 🦽 Often require prolonged rehab; less likely to be fully independent.

📚 References

• Hart RG, Diener HC, Coutts SB. Embolic strokes of undetermined source. Lancet Neurol. 2014.
• Adams HP Jr et al. TOAST classification of stroke subtypes. Stroke. 1993.
• January CT et al. 2019 AHA/ACC/HRS AF management update. Circulation. 2019.
• AHA/ASA. Guidelines for early management of acute ischaemic stroke. Stroke. 2019.
• Arboix A, Alió J. Cardioembolic Stroke. Curr Cardiol Rev. 2010.