Cera™ ASD Occluder Post-Market Clinical Follow-Up Study

Inclusion Criteria: * Patients with a confirmed diagnosis of secundum Atrial Septal Defect (ASD). * Patients was implanted with the study device from 01 Jan 2020 to 31 Dec 2023 as per IFU instructions. * Patients or legally authorized representative are willing to the collection and processing of his/her data or sign the Informed Consent. Exclusion Criteria: * Patients who have extensive congenital cardiac anomaly which can only be adequately repaired by cardiac surgery. * Patients who have sepsis within one month prior to implantation, or any systemic infection that can't be successfully treated prior to device placement. * Patients known to have a bleeding disorder, untreated ulcer or any other contraindications to aspirin therapy, unless another anti-platelet agent can be administered for 6 months. * Patients who have demonstrated intra-cardiac thrombi on echocardiography (especially left atrial or left atrial appendage thrombi). * Patients whose size (i.e., too small to tolerate TEE probe, catheter size, etc.) or condition (active infection, etc.) would cause the patient to be a poor candidate for cardiac catheterization. * Patients where the margins of the defect are less than 5mm from the coronary sinus, AV valves or right upper lobe pulmonary vein. * Patients did not conduct any follow up visit after hospital discharge.