Safety and Efficacy of IrisFIT™ Patent Foramen Ovale Occluders

Inclusion Criteria: 1. Patients aged 18-60 years; 2. Be able to understand the purpose of the experiment, voluntarily participate in the experiment and sign the informed consent; 3. Patent foramen ovale was confirmed by chest ultrasound (TTE) or esophageal ultrasound (TEE); 4. The presence of a large right-to-left shunt was confirmed by right aspiration angiography (cTTE or cTCD); 5. It meets the clinical status of patent foramen ovale plugging indication, and at least one of the following conditions exists: 1. Cryptogenic stroke complicated with patent foramen ovale, combined with one or more clinical risk factors; 2. Cryptogenic stroke complicated with patent foramen ovale, combined with one or more anatomical risk factors of patent foramen ovale; 3. Cryptogenic stroke complicated with patent foramen ovale, with clear deep vein thrombosis or pulmonary embolism, and not suitable for anticoagulant therapy; 4. Cryptogenic stroke complicated with patent foramen ovale, but still recurred with antiplatelet or anticoagulant therapy. Exclusion Criteria: 1. Carotid atherosclerotic stenosis was determined by the investigator based on CT or vascular ultrasound (\> 50%); 2. Large cerebral infarction occurred within 4 weeks (MR/CT or DWI image ASPECTS score \<6 points or infarction volume ≥70 ml or infarction area \> 1/3 middle cerebral artery blood supply area); 3. intracardiac thrombosis or tumor, intracardiac neoplasm; 4. acute myocardial infarction or unstable angina within 6 months; 5. Left ventricular aneurysm formation or left ventricular wall movement disorder; 6. Mitral/aortic disease: including mitral stenosis or severe mitral regurgitation of any cause, severe aortic stenosis or severe aortic regurgitation, mitral or aortic valve vegetations or prior valve replacement surgery; 7. Dilated cardiomyopathy, LVEF \< 35%, or other severe heart failure; 8. Patients with right-to-left shunt due to other causes, including atrial septal defect or perforated diaphragm; 9. Atrial fibrillation/atrial flutter (chronic or intermittent); 10. pregnant or planning to become pregnant during the trial; 11. Patients with active endocarditis or other untreated infections or other hemorrhagic diseases; 12. Pulmonary hypertension or patent foramen ovale was a special channel; 13. liver and kidney function impairment (ALT or AST \> 3 times the upper limit of normal value, serum creatinine (Cr) \> 2 times the upper limit of normal value); 14. Uncontrolled hypertension (\> 180/100 mmHg); 15. Contraindication of antiplatelet or anticoagulant therapy, such as severe bleeding within 3 months, obvious retinopathy, history of other intracranial bleeding, and obvious intracranial diseases; 16. Coronary heart disease, hypertension, diabetes and other vascular diseases that are poorly controlled by drugs or other means; 17. The investigator determined that the patient was not suitable for implantation of PFO occluder (for example, the diameter of the base of the atrial septal tumor ≥25mm and the size of the foramen ovale ≥5mm) or the patient has contraindications for implantation of PFO occluder; 18. Thrombosis exists at the location or route of implantation; 19. Malignant neoplasms or other diseases with a life expectancy of less than 2 years; 20. Patients who could not be followed up during the trial; 21. Participate in clinical trials of other drugs or medical devices within three months.