Recruiting

Sphere-9 Catheter

Sponsor:

Medtronic Cardiac Ablation Solutions

Code:

NCT07298473

Conditions

Atrial Fibrillation (AF)

Persistent Atrial Fibrillation

Paroxysmal Atrial Fibrillation (PAF)

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Sphere-9 Catheter Ablation

Study Details

Brief summary:

Conquer-AF is a prospective, multi-center, interventional, non-randomized clinical study that will enroll up to 400 subjects at up to 30 sites across the United States, Europe, and Australia.

Subjects diagnosed with symptomatic recurrent paroxysmal or persistent atrial fibrillation after a single prior ablation procedure will be enrolled in this study. Each subject will undergo a study index redo ablation procedure using the Sphere-9 Catheter and Affera Ablation System and will be followed for 12 months. The expected total study duration (from time of first enrollment to the exit of last enrolled subject) is approximately 2 years.

Conditions

Atrial Fibrillation (AF)

Persistent Atrial Fibrillation

Paroxysmal Atrial Fibrillation (PAF)

Study ID

NCT07298473

Start date

Apr 8, 2026

Status verified date

Apr, 2026

Completion date

Mar 29, 2028

Anticipated

Primary completion date

Mar 29, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

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

Study Design

Enrollment

400 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Single Arm: Redo AF Ablation with Sphere-9 Catheter

Participants undergo a redo atrial fibrillation ablation using the Sphere-9 Catheter and the Affera Ablation System per study protocol. All subjects receive the same intervention with no control or comparator arm.

Interventions

Sphere-9 Catheter Ablation

Redo atrial fibrillation ablation performed using the Sphere-9 Catheter in conjunction with the Affera Ablation System and Affera Mapping System. The intervention delivers radiofrequency and pulsed field energy according to the study protocol for treatment of recurrent paroxysmal or persistent AF. All participants receive this device-based ablation procedure.

Primary outcome measure

  • Effectiveness: Number of Participants With Treatment Success. [ Time Frame: 12-months post-redo ablation procedure ]
  • Safety: Number of Participants With at Least One Primary Safety Event [ Time Frame: 6-months post-redo ablation procedure ]

Central Contacts and Locations

Central contacts

Ryan S Radtke, Bachelors of Science- Biology

712-941-9372ryan.s.radtke@medtronic.com

Locations

University of Alabama at Birmingham (UAB) Hospital

Recruiting

Birmingham, Alabama, United States, 35233

Contacts

Hugh Thomas McElderry

(205) 934-2525tommcelderry@uabmc.edu

Principal Investigator:

Hugh Thomas McElderry, MD

Cedars Sinai Medical Center

Recruiting

Los Angeles, California, United States, 90048-1804

Contacts

Michael Shehata

310-423-3277michael.shehata@cshs.org

Principal Investigator:

Michael Shehata, MD

NCH Rooney Heart Institute

Recruiting

Naples, Florida, United States, 34102

Contacts

Dinesh Sharma

239-624-5000dinesh.sharma@nchmd.org

Principal Investigator:

Dinesh Sharma, MD

Piedmont Heart Institute

Recruiting

Atlanta, Georgia, United States, 30309

Contacts

Sandeep Goyal

404-605-5000sandeep.goyal@piedmont.org

Principal Investigator:

Sandeep Goyal, MD

Memorial Health University Medical Center

Recruiting

Savannah, Georgia, United States, 31404

Contacts

Todd Senn

912-350-8000todd.senn@hcahealthcare.com

Principal Investigator:

Todd Senn, MD

Massachusetts General Hospital

Recruiting

Boston, Massachusetts, United States, 02114-2621

Contacts

Moussa Mansour

(617) 726-2928mmansour@mgh.harvard.edu

Principal Investigator:

Moussa Mansour, MD

Northwell Health Lenox Hill Hospital

Recruiting

New Hyde Park, New York, United States, 11040-1402

Contacts

Haisam Ismail

(718) 470-7330hismail@northwell.edu

Principal Investigator:

Haisam Ismail, MD

NYU Langone Health

Recruiting

New York, New York, United States, 10016-4972

Contacts

Larry Chinitz

212-263-7300larry.chinitz@nyulangone.org

Principal Investigator:

Larry Chinitz, MD

Montefiore Medical Center

Recruiting

The Bronx, New York, United States, 10467

Contacts

Luigi Di Biase

(718) 920-4116ldibiase@montefiore.org

Principal Investigator:

Luigi Di Biase, MD

Cleveland Clinic Foundation

Recruiting

Cleveland, Ohio, United States, 44195

Contacts

Ayman Hussein

(216) 444-6697husseia@ccf.org

Principal Investigator:

Ayman Hussein, MD

OhioHealth Research and Innovation Institute (OHRI)

Recruiting

Columbus, Ohio, United States, 43214-3467

Contacts

Anish Amin

(614) 262-6772anish.amin@ohiohealth.com

Principal Investigator:

Anish Amin, MD

Hospital of the University of Pennsylvania

Recruiting

Philadelphia, Pennsylvania, United States, 19104

Contacts

Saman Nazarian

(215) 615-5220saman.nazarian@pennmedicine.upenn.edu

Principal Investigator:

Saman Nazarian, MD

Allegheny General Hospital

Recruiting

Pittsburgh, Pennsylvania, United States, 15212-4756

Contacts

Amit Thosani

(412) 310-6711amit.thosani@ahn.org

Principal Investigator:

Amit Thosani, MD

Vanderbilt University Medical Center

Recruiting

Nashville, Tennessee, United States, 37232-0019

Contacts

Zachary Yoneda

(615) 457-7391zachary.t.yoneda@vumc.org

Principal Investigator:

Zachary Yoneda, MD

Texas Cardiac Arrhythmia Research Foundation

Recruiting

Dallas, Texas, United States, 75226

Contacts

Andrea Natale

(512) 807-3150tcarfan@gmail.com

Principal Investigator:

Andrea Natale, MD

Texas Health Fort Worth

Recruiting

Fort Worth, Texas, United States, 76104

Contacts

Theodore Takata

817-250-2000theodoretakata@texashealth.org

Principal Investigator:

Theodore Takata, MD

Inova Fairfax Hospital

Recruiting

Falls Church, Virginia, United States, 22042

Contacts

Stephen Gaeta

703-776-4001stephen.gaeta@inova.org

Principal Investigator:

Stephen Gaeta, MD

Centra Medical Group Stroobants Cardiovascular Center

Recruiting

Lynchburg, Virginia, United States, 24501

Contacts

Chinmaya Mareddy

434-200-3000chinmaya.mareddy@centrahealth.com

Principal Investigator:

Chinmaya Mareddy, MD

Sentara Norfolk General Hospital

Recruiting

Newport News, Virginia, United States, 23606-2981

Contacts

Venkat Iyer

(757) 499-2825viyer@cval.org

Principal Investigator:

Venkat Iyer, MD

More Information

Sponsor

Medtronic Cardiac Ablation Solutions

Last update posted

Jul 31, 2026

Last verified

Apr, 2026

Keywords

  • Sphere-9 Catheter
  • Affera Ablation System
  • Affera Mapping System
  • Pulsed Field Ablation (PFA)
  • Radiofrequency Ablation (RFA)
  • Dual-Energy Ablation
  • Atrial Fibrillation
  • Paroxysmal Atrial Fibrillation
  • Persistent Atrial Fibrillation
  • Redo Ablation
  • Repeat Ablation
  • Electrophysiology Mapping
  • 3D Cardiac Mapping
  • Left Atrial Ablation
  • Redo AF Ablation
  • Repeat Ablation Procedures

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Medtronic Cardiac Ablation Solutions on 2026-07-31.