Table 3: Secondary Prevention in Patients with PFO-Associated Stroke: Risk Stratification-Based Recommendations

RISK STRATIFICATION	HIGH RISK	MODERATE RISK	LOW RISK
Absolute criterion	Required	Required	Required
No other potential cause of stroke than PFO
Major criteria	1 criterion	1 criterion	0 criterion
Evidence of deep vein thrombosis
Evidence of a hypercoagulable state
Stroke recurrence despite antithrombotic treatment
Minor criteria	≥1 criteria	0 criteria	0 criterion
Massive right-to-left shunt
Interatrial septal aneurysm
Multiple clinical cerebrovascular events and/or multiple ischemic lesions at brain MRI
Recommended therapy:	Transcatheter closure	Anticoagulation INR 2-3 / closure	Anti-platelet therapy