A Study of Dual Energy THERMOCOOL SMARTTOUCH™ SF Catheter With TRUPULSE™ Generator in Persistent Atrial Fibrillation

• Radiofrequency/Pulsed Field Ablation (Device): Radiofrequency and pulsed field ablation by Dual Energy THERMOCOOL SMARTTOUCH™ SF (DE STSF) catheter with the TRUPULSE™ generator will be used.

Primary outcomes

• Freedom from Documented (Symptomatic and Asymptomatic) Atrial Tachyarrhythmia Episodes [Day 91 up to Day 365 post index procedure]: Number of participants reporting freedom from documented (symptomatic and asymptomatic) atrial tachyarrhythmia (that is, atrial fibrillation or atrial tachycardia or atrial flutter \[AF, AT or AFL\] of unknown origin) episodes based on electrocardiographic data and freedom from acute procedural failure, repeat ablation failure, non-study device failure, antiarrhythmic drug (AAD) failure, continuous AF/AT/AFL of unknown origin, and any direct current (DC) cardioversion procedure will be reported.
• Occurrence of Early Onset Primary Adverse Event (PAE) [Within 7 days post index procedure]: PAEs include the following Adverse Events (AEs): esophageal perforating complications (Atrio-esophageal fistula occuring up to 90 days post ablation procedure); phrenic nerve paralysis; cardiac Tamponade, perforation (occuring up to 30 days post ablation procedure); pulmonary vein stenosis (anytime during the 12 month follow up period); device or procedure related death (anytime during or after the ablation procedure); stroke/CVA; major vascular access complication/bleeding; thromboembolism; myocardial infarction; transient ischemic attack (TIA); pericarditis; heart block; pulmonary Edema (Respiratory Insufficiency); and vagal Nerve Injury/gastroparesis.

Secondary outcomes

• Change From Baseline in Quality of life, As Measured by the Total Atrial Fibrillation Effect on Quality-of-Life (AFEQT) Score at 12 Months Post Procedure [Baseline, At 12 months post procedure]: The AFEQT uses a questionnaire to evaluate symptoms, daily activities and treatment concerns participants have related to atrial fibrillation. An overall AFEQT score ranges from 20 to 140. A score of 140 represents extreme distress (or extreme limitation, dissatisfaction or difficulty), while a score of 20 corresponds to no disability (or responding "not at all" limited, difficult or extreme satisfaction).

Sex: All, ages: 18 Years to 80 Years

Inclusion criteria:

* Documented symptomatic persistent atrial fibrillation (AF), which is defined as continuous AF that sustains beyond 7 days and less than 1 year and is documented by the following: Physician's note indicating continuous AF greater than or equal to (>=) 7 days but no more than 1 year; AND 1) Two electrocardiograms (from any forms of rhythm monitoring) showing continuous AF, with electrocardiogram taken at least 7 days apart (electrograms cannot >12 months prior to enrollment) OR 2) At least 24-hour Holter/ telemetry strip within 12 months prior to enrollment showing continuous AF
* Failed at least one (1) antiarrhythmic drug (AAD) (Class I or Class III) as evidenced by recurrent symptomatic AF, intolerable to the AAD
* Age 18-80 years
* Willing and capable of providing consent
* Able and willing to comply with all pre-, post- and follow-up testing and requirement

Exclusion criteria:

* AF secondary to electrolyte imbalance, thyroid disease, or reversible or non-cardiac cause (for example, documented obstructive sleep apnea, acute alcohol toxicity, etcetera)
* Documented severe dilatation of the left atrium (LA) (LAD >50 millimetre \[mm\]) antero-posterior diameter on imaging within 6 months prior to procedure
* Documented severely compromised left ventricular ejection fraction (LVEF) (LVEF less than \[<\] 40 percent \[%\]) by imaging within 6 months prior to procedure
* Severe mitral regurgitation or insufficiency, or the report claims: Regurgitant volume >=60 millilitre (mL)/beat, Regurgitant fraction >=50%, and/or effective regurgitant orifice area >=0.40 square centimetre (cm\^2).
* Moderate-severe, severe tricuspid valve regurgitation or insufficiency
* Documented LA thrombus by imaging within 48 hours of the procedure or by intracardiac echocardiography (ICE) prior to transeptal puncture during procedure
* Concomitant other arrhythmia, including: atrioventricular reentrant tachycardia, atrioventricular nodal reentry tachycardia, atrial flutter of unknown origin, ventricular tachycardia and Wolff-Parkinson-Whiteexcept cavotricuspid isthmus (CTI) lines for the ablation of typical right atrial flutter
* Previous LA ablation or surgery
* Valvular cardiac surgical/percutaneous procedure (that is, ventriculotomy, atriotomy, valve repair or replacement and presence of a prosthetic valve)
* Anticipated cardiac transplantation, cardiac surgery, or other major surgery within the next 12 months
* Uncontrolled heart failure or New York Heart Association (NYHA) Class III or IV
* History of blood clotting, bleeding abnormalities or contraindication to anticoagulation (heparin, etcetera)
* Documented thromboembolic event (including transient ischemic attack \[TIA\]) within the past 12 months
* History of a documented symptomatic lacunar infarction within the past 12 months
* Participants with percutaneous coronary intervention or acute myocardial infarction within 3 months
* Coronary artery bypass grafting (CABG) surgery within the past 6 months (180 days)
* Unstable angina within the past 6 months
* Significant pulmonary disease (for example, restrictive pulmonary disease, constrictive or chronic obstructive pulmonary disease) or any other disease or malfunction of the lungs or respiratory system that produces severe chronic symptoms
* Significant congenital anomaly (for example, american society for dermatologic surgery \[ASDs\]) including treated or medical problem that in the opinion of the investigator would preclude enrollment in this study
* Presence of intracardiac thrombus, myxoma, tumor, interatrial baffle or patch or other abnormality that precludes catheter introduction or manipulation
* Presence of a condition that precludes vascular access
* Prior diagnosis of pulmonary vein stenosis
* Pre-existing hemi diaphragmatic paralysis
* Acute illness, active systemic infection, or sepsis
* Participant has an implanted metal cardiac device, including MitraClip and left atrial appendage occlusion (LAAO) devices (for example, WATCHMAN, Amulet, etcetera) (this exclusion does not include coronary stents, implanted pacemakers, implantable cardioverter-defibrillators \[ICD\] and implantable loop recorders \[ILR\])
* Current enrollment in an investigational study evaluating another device or drug
* Women who are pregnant (as evidenced by pregnancy test if pre- menopausal), lactating, or who are of child-bearing age and plan on becoming pregnant during the course of the clinical investigation
* Life expectancy less than 12 months
* History of massive haemorrhage within the past 6 months
* Those considered by the investigators as not suitable for participating in this clinical study

• Biosense Webster, Inc. Clinical Trial, Study director, Biosense Webster, Inc.