Patients who underwent both bubble transcranial Doppler (bubble-TCD) and transoesophageal echocardiography (TEE) at our institution were consecutively enrolled in this real-world case-control study from August 2016 through August 2023. The patients were categorized into three groups based on the degree of the shunt observed: mild (3-9 bubbles), moderate (10-30bubbles), and severe (more than 30 bubbles). In cases with mild-shunt (small-size) PFO, post-procedural anticoagulation or PFO closure was administered. Subsequent to the interventions, the follow-up encompassed the recording of migraine remission, recurrent neurological incidents, instances of major bleeding, and mortality.

Inclusion Criteria:

1. verified PFO diagnosis through TEE, Bubble-TCD, or contrast echocardiography of the right heart;
2. ages range between 16 and 65;
3. no restrictions on sexual orientation;
4. stroke patients with cryptogenic strokes as per the TOAST classification;
5. no other likely causes for migraines, with the exception of PFO;
6. no multiple risk factors for cerebrovascular disease, such as hypertension, diabetes, or smoking.

Exclusion Criteria:

• 1)severe, acute, or life-threatening conditions including acute cardio-cerebrovascular diseases, significant organ failure, or infections; 2)magnetic resonance imaging (MRI) contraindications, especially with contrast enhancement; 3) presence of cerebral artery stenosis, internal carotid artery stenosis, or atherosclerosis; 4) hypercoagulability or venous thrombosis; 5) contraindications associated with PFO closure and anticoagulants; 6) obstructive sleep apnea.

Eligible participants had their PFO diagnosis confirmed via transoesophageal echocardiography (TEE), bubble transcranial Doppler (Bubble-TCD), or contrast echocardiography of the right heart and gave their informed consent to participate