SPHERE Per-AF Post-Approval Study is a prospective, multi-center, non-randomized, observational trial. Subjects will be treated with the Sphere-9™ Catheter and Affera™ Ablation System and followed through 36 months.

The purpose of the study is to evaluate the long-term effectiveness and safety of the Sphere-9™ Catheter and Affera™ Ablation System in a post-approval setting for the treatment of drug refractory, recurrent, symptomatic, persistent AF (episode duration less than one year).

Inclusion Criteria:

1. A diagnosis of recurrent symptomatic persistent AF (continuous AF sustained longer than 7 days but less than 12 months)
2. Refractory (i.e. not effective, not tolerated, or not desired) to at least one Class I or III antiarrhythmic drug (AAD)
3. Patient is ≥ 18 years of age
4. Planned de novo pulmonary vein isolation procedure using commercially available Sphere-9™ Catheter and Affera Ablation System
5. Patient is willing and able to comply with study requirements and give informed consent

Exclusion Criteria:

1. Long-standing persistent AF (continuous AF sustained >12 months)
2. Prior left atrial catheter or surgical ablation
3. Life expectancy <36 months
4. 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)
5. Current or anticipated participation in any other clinical trial of a drug, device or biologic during the duration of this study not pre-approved by Medtronic

Subjects 18 years or older with a planned de novo procedure using commercially available Sphere-9™ Catheter and Affera™ Ablation System.