Redo AF ablation using the Sphere-9 catheter and Affera system for recurrent paroxysmal and persistent atrial fibrillation

Inclusion Criteria:

* 1\. History of a single AF ablation procedure for PAF or PsAF within 3 years prior to enrollment 2. Documented evidence of symptomatic AF, AT or AFL recurrence at least 90 days after subject's de novo ablation procedure, as demonstrated by:

  * A physicians' note indicating at least 1 symptomatic AF, AT, or AFL episode occurring within 12 months prior to the enrollment; and
  * At least 1 electrocardiographically documented episode of AF, AT, or AFL within 12 months prior to enrollment 3. Adults who are ≥18 years of age on the day of enrollment 4. Willing and able to comply with all study requirements and provide informed consent

Exclusion Criteria:

* 1\. Continuous AF lasting for 12 months or longer 2. LA anteroposterior \>55 mm (by MRI, CT, or TTE), or if LA diameter not available, non-index volume \>100 mL for PsAF subjects; OR LA anteroposterior \>50 mm (by MRI, CT, or TTE), or if LA diameter not available, non-index volume \>95 mL for PAF subjects 3. Previous left atrial percutaneous interventions including left atrial appendage occlusion and septal closure devices 4. Planned left atrial appendage (LAA) closure procedure, cardiac transplantation or implant of a permanent pacemaker, biventricular pacemaker, loop recorder/insertable cardiac monitor (ICM), or any type of implantable cardiac defibrillator (with or without biventricular pacing function) for any time during the follow-up period 5. More than 1 previous AF ablation procedure 6. Any prior surgical ablation procedure 7. Patient who is not on oral anticoagulation therapy for at least 3 weeks prior to the ablation procedure 8. Contraindication to or unwillingness to use systemic anticoagulation 9. Severe thrombocytosis, thrombocytopenia, or any bleeding or clotting disorder 10. Presence of a permanent pacemaker, biventricular pacemaker, loop recorder/insertable cardiac monitor (ICM), or any type of implantable cardiac defibrillator (with or without biventricular pacing function) 11. Presence of any pulmonary vein stents 12. Known pre-existing pulmonary vein stenosis 13. Pre-existing hemidiaphragmatic paralysis 14. Prior valvular (surgical or percutaneous) procedure including prosthetic, bioprosthetic, valve replacement, valve repair or valvuloplasty, or any prior atriotomy 15. Moderate to severe mitral valve or aortic stenosis 16. Moderate to severe mitral regurgitation (i.e., 3+ or 4+ MR) 17. Any cardiac surgery, myocardial infarction, PCI/PTCA or coronary artery stenting which occurred within the 3 months preceding the consent date 18. NYHA Class III or IV congestive heart failure 19. Documented left ventricular ejection fraction (LVEF) ≤40%, measured by acceptable cardiac testing (e.g., TTE) 20. Unstable angina 21. Severe lung disease, primary pulmonary hypertension, or any lung disease requiring supplemental oxygen 22. Rheumatic heart disease 23. Significant restrictive or obstructive pulmonary disease or chronic respiratory condition 24. Presence of left atrial thrombus on imaging 25. Active systemic infection or sepsis 26. Hypertrophic cardiomyopathy 27. Amyloid heart disease 28. Diagnosed atrial myxoma 29. Known reversible causes of AF (e.g., uncontrolled hyperthyroidism, severe untreated obstructive sleep apnea, acute alcohol toxicity or other reversible or non-cardiac cause) 30. Any cerebral ischemic event (strokes or TIAs) which occurred within the preceding 6 months of the consent date through the date of study index redo ablation procedure 31. Carotid stenting or endarterectomy 32. Thromboembolic event within the past 6 months or evidence of intracardiac thrombus at the time of the procedure 33. Body mass index \> 40 kg/m2 34. Any woman known to be pregnant or breastfeeding, or any woman of childbearing potential who is not on a reliable form of birth regulation method or abstinence\* 35. Patient with life expectancy that makes it unlikely 12 months of follow-up will be completed 36. Current or anticipated participation in any other clinical study of a drug, device or biologic during the duration of the study not pre-approved by Medtronic 37. Renal insufficiency with an estimated glomerular filtration rate (eGFR) \<30 mL/min/1.73 m2, or any history of renal failure requiring dialysis or renal transplant 38. Presence of intramural thrombus, tumor, or other abnormality that precludes vascular access, catheter introduction, or manipulation 39. Presence of an inferior vena cava (IVC) filter (e.g., Greenfield or similar) that would preclude safe transfemoral venous access, catheter passage, or sheath manipulation.

  40\. Known drug or alcohol dependency 41. Significant congenital anomaly or medical problem that would, in the opinion of the investigator, preclude enrollment, follow-up compliance, or the scientific integrity of the study

  \*Women who are of child-bearing potential must undergo a pregnancy test after consent and prior to the study index redo ablation procedure, as allowed according to local regulations