Effectiveness and Safety of Transcatheter Patent Foramen Ovale Closure for Migraine

Inclusion Criteria: * Clinical history of migraine diagnosed by a neurologist according to the International Classification of Headache Disorders * Transcranial Doppler evidence of right-to-left shunt(RLS) and echocardiographic evidence of PFO，of which the degree is moderate to large RLS * Subjects who have not responded to or cannot take common migraine preventive medications * Willing to participate in follow-up visits Additional Inclusion Criteria: * Transcatheter closure group: Closure of PFO is performed * Contrast group: Subjects who meet the Inclusion Criteria, but refuse to undergo closure procedure Exclusion Criteria: * Seizure disorder * Other organic central nervous system disease * Subjects whose headaches are other than migraine, such as a result of traumatic head or neck injury * Evidence of alcohol, drug or substance abuse within the previous year Additional Exclusion Criteria for Transcatheter closure group: * Subjects with intracardiac thrombus or tumor * Subjects who have an acute or recent (within 6 months) myocardial infarction or unstable angina * Subjects with left ventricular aneurysm or akinesis * Subjects with atrial fibrillation/atrial flutter (chronic or intermittent) * Subjects with another source of right to left shunt identified at baseline, including an atrial septal defect and/or fenestrated septum * Subjects with contraindication to aspirin or Clopidogrel therapy * Pregnant or desire to become pregnant within the next year