Safety and Efficacy Study of reSept ASD Occluder for Treating Secundum ASD

Inclusion Criteria: All responses must be Yes to be eligible:

1. Age < 85 years.
2. Body weight ≥ 15 kg / 33 lb.
3. Males and Females.
4. Clinically significant, isolated secundum ASD associated with a L-R shunt and signs ofRV volume overload that, based upon the expertise of attending physicians requirestreatment.
5. ASD of size 5 to 19 mm on screening diagnostic echocardiogram.
6. Isolated secundum ASD of size 8 to 22 mm on stop flow balloon diameter, based uponechocardiographic and fluoroscopic evidence obtained at procedure.
7. Able to take required medications: ASA (Aspirin), low dose (75-100 mg/day), 24 hoursprior to and for 6 months following the procedure; Heparin intra-procedurally.
8. Adequate septal rim to support the device. The rim is considered inadequate if itmeasures less than 5mm in more than two views of a critical structure
9. Adequate defect margin to safely accommodate the selected size implant withoutinterfering with adjacent cardiac structures (e.g., aorta, AV valves, ostia of thepulmonary veins, coronary sinus, or other critical structures), based on the IFUsizing guidance.
10. Capable of giving informed consent, or, for minors, consent of the parent or legalguardian, and willing to comply with the clinical investigation requirements.

Exclusion Criteria: All responses must be No to be eligible:

1. Pregnancy. Females with child-bearing potential are required to be tested forpregnancy prior to treatment, in accordance with the local institution's policy. Forminor females, a pregnancy test will be done in accordance with the localinstitution's policy.
2. Any significant valve dysfunction that contraindicates ASD closure, or increasedpulmonary vascular resistance/severe pulmonary hypertension.
3. Acquired pathological or congenital abnormalities of the cardiovascular system (otherthan isolated secundum ASD; e.g. congenital malformations, calcification, myocardialinfarction, intracardiac thrombi, dilated cardiomyopathy, untreated coronary diseaseor CAD treated with a stent in the prior 12 months) being clinically significant, thatwould interfere with the conduct of the clinical investigation.
4. Subjects having undergone left sided structural heart interventions performed viatransseptal access (e.g. Mitraclip, LAAO, percutaneous mitral valve replacement).
5. Evidence of thrombus in the left atrium, left atrial appendage, other cardiac chamber,or the inferior vena cava.
6. Sepsis or any other infection that was not successfully treated at least 30 days priorto device placement.
7. Active endocarditis or other infection(s) producing bacteremia.
8. History of atrial tachycardia, atrial fibrillation or flutter, AV block, orventricular arrhythmia requiring antiarrhythmic medication, pacemaker or AICD.
9. Vasculature is of inadequate size to accommodate all procedural instrumentation.
10. Known allergy to investigational device components or medications, or othercontraindication to clinical investigation medications (acetylsalicylic acid,heparin), including a documented history of bleeding, clotting or coagulationdisorders, untreated ulcer or any other contraindications to acetylsalicylic acid orantiplatelet therapy.
11. Known hypercoagulable state.
12. Any disorder in the investigator's opinion that could interfere with compliance ofsafety evaluation as well as any severe concurrent illness that would limit lifeexpectancy (e.g. malignancies).
13. Currently an active subject in an investigational drug or device study that couldconfound the results of this study.
14. Patients who, in the opinion of the investigator, are inappropriate for inclusion intothis clinical investigation or will not comply with requirements of the clinicalinvestigation.
15. Are known to abuse drugs or alcohol.
16. Patients with the diagnosis of Patent Foramen Ovale (PFO).