Append Prague Study

This study is intended to evaluate the safety and feasibility of the Append System for left atrial appendage (LAA) elimination using a transcatheter procedure that invaginates and ligates the LAA tissue.

Inclusion Criteria: 1. Male or non-pregnant female aged ≥18 years 2. Documented non-valvular AF (paroxysmal, persistent, permanent or non-rheumatic valve-related AF) 3. The subject has a calculated CHA2DS2-VASc score of 2 or greater for males or 3 or greater for females. 4. The subject is eligible for the defined protocol medication regimen of anticoagulation and antiplatelet therapy following Append procedure. 5. The patient is deemed appropriate for LAA ligation by the screening committee and the investigator. 6. The patient has been informed of the nature of the study, agrees to its provisions \& follow-up evaluations, and has provided written informed consent approved by the appropriate Institutional Review Board (IRB) or Ethics Committee (EC). Exclusion Criteria: 1. Pregnant or nursing patients and those who plan pregnancy in the period up to 1 year following the index procedure. Female patients of childbearing potential must have a negative pregnancy test (per site standard test) within 7 days prior to index procedure. 2. Atrial fibrillation that is defined by a single occurrence or that is considered to be reversible (e.g., due to thyroid disorders, acute alcohol intoxication, trauma, or recent major surgical procedures). 3. Patients with an indication for chronic oral anticoagulation other than AF (e.g., history of unprovoked deep vein thrombosis or pulmonary embolism, or mechanical heart valve) 4. Clinically significant Severe heart failure (New York Heart Association functional class IV) 5. Prior cardiac surgery or surgery requiring sternotomy 6. Recent (within 3 months pre-procedure) stroke or transient ischemic attack. 7. Recent (within 3 months pre-procedure) myocardial infarction 8. Recent (within 30 days before the index procedure) or planned (within 60 days after the index procedure) cardiac interventional procedures (e.g., percutaneous coronary intervention, structural heart valve procedures, etc.), not including catheter ablation. 9. Planned (within 60 days after the index procedure) cardiac surgical procedures or any surgeries which require sternotomy. 10. Recent (within 30 days before the index procedure) or planned (within 60 days after the index procedure) noncardiac procedures or surgical interventions. 11. History of symptomatic pericarditis (acute or chronic). 12. Patient has evidence of cardiac tumor 13. Renal insufficiency, defined as estimated glomerular filtration rate (eGFR) \