Carotid Artery Implant for Trapping Upstream Emboli for Preventing Stroke in Atrial Fibrillation Patients

Inclusion Criteria: 1. Atrial fibrillation (AF): documented persistent or permanent 2. CHA2DS2-VASc score ≥ 4 3. Age \> 50 4. Unsuitable for oral anticoagulation therapy (OAC), defined as contraindicated for OAC, patient refusing OAC, or physician is reluctant to prescribe OAC 5. Maximal (systolic) CCA diameter range: ≥ 5.3mm and ≤ 9.8mm 6. CCA accessibility: up to 60mm from skin to CCA center, safe approach 7. Patient is willing to provide informed consent 8. Patient is willing to complete all scheduled follow-up Exclusion Criteria: 1. Evidence of carotid stenosis \> 30% \[CCA, internal carotid artery (ICA), or external carotid artery (ECA) 2. Evidence of any atherosclerotic disease in CCA above the clavicles 3. Evidence of carotid dissection 4. Pre-existing stent(s) in CCA 5. Contraindicated or allergic to antiplatelet therapy, or any medication required during the study 6. Recent stroke, TIA, or myocardial infarction (MI) within two months prior to index procedure 7. Female who is pregnant or who is planning to become pregnant during the course of the study 8. Life expectancy of less than 1 year 9. Active systemic infection 10. Known sensitivity to nickel or titanium metals, or their alloys 11. Known hereditary or acquired coagulation disorders 12. Any planned surgical or endovascular procedure within 14 days prior to or 30 days after the index procedure 13. A co-morbid disease or condition that could confound the neurological and functional evaluations or compromise survival or ability to complete follow-up assessments 14. Current use or a recent history of illicit drug(s) use or alcohol abuse (defined as regular or daily consumption of more than four alcoholic drinks per day) 15. Active participation in another investigational drug or device treatment study 16. Any other condition that in the opinion of the investigator may adversely affect the safety of the subject or would limit the subject's ability to complete the study