What is the best initial intervention for a patient presenting with a new stroke and a patent foramen ovale (PFO)?

Management of Stroke in Patients with Patent Foramen Ovale (PFO)

For patients with a recent ischemic stroke attributed to a PFO, PFO closure plus long-term antiplatelet therapy is recommended as the best intervention for carefully selected patients aged 18-60 years with confirmed non-lacunar embolic stroke and no alternative etiologies. 1

Patient Selection Algorithm for PFO Management

Step 1: Evaluate PFO Causality

• Complete evaluation by clinicians with both stroke and cardiovascular expertise 1, 2
• Confirm diagnosis of non-lacunar embolic ischemic stroke by imaging 1
• Rule out alternative etiologies through:
  • Prolonged rhythm monitoring
  • Transoesophageal echocardiography
  • Carotid ultrasonography
  • CT or MRI to assess cerebrovascular disease 2

Step 2: Determine Treatment Based on Patient Characteristics

For patients aged 18-60 years with PFO-attributed stroke:

1. PFO closure plus long-term antiplatelet therapy is the preferred intervention when:

   • Stroke is confirmed as non-lacunar embolic ischemic stroke
   • PFO is determined to be the most likely cause after thorough evaluation
   • Patient has high-risk PFO features (large shunt or associated atrial septal aneurysm) 1, 3

2. Antiplatelet therapy is recommended when:

   • Patient does not undergo PFO closure
   • No separate indication exists for anticoagulation 1

3. Anticoagulation should be considered when:

   • Patient has hypercoagulable state or evidence of venous thrombosis
   • Patient experiences recurrent cerebral ischemic events despite antiplatelet therapy 2

For patients >60 years with PFO:

• Antiplatelet therapy alone is recommended as PFO is more likely incidental rather than causal 1, 2
• PFO closure is not recommended 1, 2

Evidence Supporting PFO Closure

The CLOSE trial demonstrated significant benefit of PFO closure with no strokes occurring in the closure group compared to 14 strokes in the antiplatelet-only group (hazard ratio 0.03) 3. A systematic review and meta-analysis confirmed that PFO closure is superior to antithrombotic therapy for preventing stroke recurrence (RR=0.36) 4.

The benefit is particularly pronounced in patients with:

• Atrial septal aneurysm or large shunt (RR=0.27) 4
• Embolic-appearing strokes 5

Antiplatelet vs. Anticoagulation

When PFO closure is not performed:

• No significant difference has been demonstrated between anticoagulation and antiplatelet therapy in preventing recurrent stroke in general PFO populations 6, 7
• The RE-SPECT ESUS study found insufficient evidence to recommend anticoagulation over antiplatelet therapy for patients with ESUS and PFO 7
• Some evidence suggests anticoagulation may benefit patients with high RoPE scores (indicating higher probability of PFO-attributable stroke) 6

Potential Complications and Considerations

PFO Closure:

• Procedural complications occur in approximately 5.9% of patients 3
• Increased risk of new-onset atrial fibrillation (4.6% vs. 0.9% with antiplatelet therapy) 3

Important Caveats:

• PFO is highly prevalent in the general population (present in about 25% of adults) 5
• The annual risk of stroke from PFO is low compared to other stroke mechanisms 5
• Assuming PFO causality in older patients without thorough evaluation is a common pitfall 2
• For patients requiring long-term anticoagulation for other reasons, the decision regarding PFO closure should be individualized based on risk-benefit profile 1

By following this evidence-based algorithm, clinicians can optimize outcomes for patients with stroke and PFO, focusing on the interventions most likely to reduce morbidity and mortality while considering patient-specific factors.