Management of Acute Ischemic Stroke Caused by Left Atrial Myxoma

1. Immediate Stroke Stabilization and Diagnostic Work‑up

Time‑of‑onset documentation is essential to determine eligibility for reperfusion therapy (intravenous thrombolysis ≤ 4.5 h, mechanical thrombectomy ≤ 24 h in selected patients). 2
Non‑contrast CT or MRI should be performed within 30 minutes of arrival to rule out intracerebral hemorrhage and to assess infarct size before any intervention. 3
Transthoracic echocardiography (TTE) must be obtained immediately when a cardiac source is suspected; if TTE is nondiagnostic, urgent transesophageal echocardiography (TEE) is required because of its superior sensitivity for left‑atrial masses. 1
CTA or MRA from the aortic arch to the vertex is recommended to identify large‑vessel occlusions amenable to thrombectomy and to screen for myxomatous aneurysms, which are present in up to 50 % of myxoma‑related embolic strokes. 1

Mechanical thrombectomy with stent‑retriever devices is effective for large‑vessel occlusions caused by myxoma emboli and should be performed within 6 h (up to 24 h in selected cases with favorable imaging). 3

Aggressive blood‑pressure reduction is contraindicated unless systolic > 220 mmHg or diastolic > 120 mmHg, because excessive lowering may worsen cerebral perfusion. 2
If blood‑pressure lowering is required, a cautious 15 % reduction using easily titratable agents (e.g., labetalol or nicardipine) is advised. 2

The American College of Cardiology gives a Class I recommendation for urgent surgical resection of symptomatic left‑atrial myxoma because the tumor has a 25 % overall embolism rate and stroke is the presenting symptom in up to 50 % of cases. 1
Urgent cardiac surgery (within 2–24 h of stroke onset) is advised when the infarct is small‑to‑moderate, the patient is neurologically stable, and no hemorrhagic transformation is evident on initial or 24‑hour follow‑up imaging. (criteria derived from cited evidence)
If hemorrhagic transformation develops, the infarct involves > 1/3 of the middle cerebral artery territory, or the patient shows neurological instability, surgery should be delayed 7–14 days. 4, 5
Complete tumor excision with an adequate atrial‑septal margin (including the fossa ovalis attachment) is required to keep recurrence risk low (1–5 % in sporadic cases). 1

Therapeutic anticoagulation (unfractionated heparin or LMWH) should not be initiated for acute stroke in the setting of myxoma because it raises hemorrhagic risk without preventing tumor embolization. 5
Anticoagulation or antiplatelet therapy alone is insufficient to prevent embolic complications and must not replace definitive surgical resection. 1
Aspirin 160–325 mg may be given 24–48 h after stroke onset (once hemorrhage is excluded) unless cardiac surgery is planned within that window. 2
If intravenous alteplase has been administered, aspirin should be delayed > 24 h post‑thrombolysis to minimize bleeding risk. 2

Subcutaneous low‑molecular‑weight heparin (e.g., enoxaparin 40 mg daily) or unfractionated heparin 5,000 IU twice daily is recommended for immobilized stroke patients. 3
Intermittent pneumatic compression should be added for additional VTE risk reduction. 3

All patients with myxoma‑related stroke should undergo CTA or MRA to screen for intracranial myxomatous aneurysms, which are fusiform lesions with a high risk of rupture. 1

Patients should be admitted to a stroke unit or neurocritical‑care unit for at least 24–48 h after surgery, as 25–30 % experience neurological worsening during this period. 5
Serial echocardiography at 6 months and then annually is advised to detect myxoma recurrence (1–5 % in sporadic cases, higher in familial Carney complex). 1

Long‑term antiplatelet therapy (clopidogrel 75 mg daily preferred over aspirin alone), high‑intensity statin therapy (target LDL < 70 mg/dL), and strict blood‑pressure control are recommended to reduce recurrent cerebrovascular events. 3

Do not postpone cardiac surgery for weeks or months in stable patients; the risk of recurrent embolization outweighs concerns about operating in the sub‑acute stroke period. 1
Do not rely on anticoagulation or antiplatelet agents as definitive therapy; they do not prevent tumor embolization nor relieve mechanical obstruction. 1
Do not assume embolic strokes in young patients are cryptogenic; obtain TEE to exclude cardiac sources such as myxoma when atherosclerotic risk factors are absent. 1