Study on the Safety and Effectiveness of a Biodegradable Patent Foramen Ovale Occluder System

This is a prospective, multicenter, randomized, controlled, non-inferiority clinical study. The study aims to evaluate the safety and efficacy of a novel biodegradable patent foramen ovale (PFO) occluder system compared to a conventional metallic occluder in patients with a PFO that is clinically determined to be associated with an PFO⁃associated stroke（PFO-AS）or transient ischemic attack (TIA).

Inclusion criteria

• Aged between 18 and 65 years.
• Presence of a patent foramen ovale (PFO) confirmed by transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE).
• Presence of a moderate-to-large right-to-left shunt (RLS) at rest or during the Valsalva maneuver, as confirmed by agitated saline contrast echocardiography (also known as bubble study).
• Clinically diagnosed with a PFO-associated ischemic stroke or transient ischemic attack (TIA).

Exclusion criteria

• An alternative, clearly identified cause of ischemic stroke or TIA (other than PFO) is determined by the investigator.
• Large territory cerebral infarction within 4 weeks prior to the planned procedure.
• Atherosclerotic stenosis (>50%) of the carotid or vertebral arteries, as confirmed by CT angiography or vascular ultrasound per investigator assessment.
• Presence of intracardiac thrombus or vegetation as confirmed by echocardiography.
• Left ventricular ejection fraction (LVEF) < 35%.
• Atrial fibrillation or atrial flutter.
• Left ventricular aneurysm or severe regional wall motion abnormality.
• Significant valvular stenosis or regurgitation, or history of valvular replacement or repair surgery.
• Pulmonary hypertension or a PFO constituting a special conduit (e.g., right-to-left shunt due to elevated right heart pressures).
• Other confirmed causes of right-to-left shunt, such as atrial septal defect (ASD) or pulmonary arteriovenous fistula.
• Complex PFO anatomy (e.g., multi-tunnel PFO) or PFO associated with an ASD requiring different closure strategy.
• Thrombus, mass, or vegetation identified at the intended implant site or along the potential delivery pathway.
• Acute myocardial infarction or unstable angina within 3 months prior to the procedure.
• Previous implantation of an inferior vena cava filter, PFO closure device, or ASD closure device.
• Any other condition deemed by the investigator to make the patient unsuitable for PFO device implantation.
• Concomitant cardiac anomalies requiring surgical correction.
• Uncontrolled systemic or local infection, or sepsis.
• Active infection requiring concurrent antibiotic therapy (Patients with transient conditions may be enrolled after completing antibiotic therapy and a subsequent 14-day washout period).
• Contraindication to antiplatelet or anticoagulant therapy (e.g., major bleeding within 3 months, known retinopathy, history of intracranial hemorrhage, or other significant intracranial pathology).
• Known hypersensitivity or allergy to tantalum or nickel.
• Pregnancy, lactation, or women of childbearing potential not using highly effective contraception.
• Life expectancy less than 1 year due to malignancy or other comorbid disease.
• Current participation in another investigational drug or device clinical study that has not yet completed its primary endpoint.