Horizon 360 Protocol for the Treatment of Paroxysmal Atrial Fibrillation With the Sphere-360™ Catheter and Affera™ Mapping and Ablation System (Horizon 360)

NCT07308847 | Recruiting DMC FDA Device

• 1 other identifier: Horizon 360
• Study Type: interventional
• Target: 300
• Locations: 1 country
• Sites: 12

Brief Summary

The study is a prospective, single-arm, pre-market clinical study and will enroll up to 300 subjects at up to 26 sites in the United States (US) for analysis of primary objectives. No single site may contribute more than 15% of the enrollments.

Conditions

Paroxysmal AF

Keywords

Paroxysmal Atrial Fibrillation; Atrial Fibrillation; Pulsed Field Ablation

Outcome Measures

Primary Outcomes (2)

• Freedom from Atrial Tachyarrhythmia Recurrence Through 12 Months Post-Ablation

  Freedom from documented recurrence of atrial fibrillation, atrial tachycardia, or atrial flutter based on electrocardiographic data through 12 months (365 days) and excluding a 90-day blanking period. The study requires 24-hour Holter monitoring at 6 and 12 months in addition to weekly and symptomatic trans-telephonic monitoring (TTM) transmissions through 12 months, and 12-lead ECGs at all follow up visits. Atrial tachyarrhythmia observed via any of those instruments, as well as acute procedural failure, repeat ablation, cardioversion, an increase in anti-arrhythmic drugs, or use of amiodarone at any time during the study will constitute a failure.

  Index ablation procedure through 12 months of follow up.

• Incidence of Device- and Procedure-Related Serious Adverse Events Through 6 Months

  Primary safety events (device- and procedure-related serious adverse events, as adjudicated by the Clinical Events Committee) for the Sphere-360 Catheter and Affera Mapping and Ablation System: Within 7 days: heart block, major bleeding needing transfusion, MI, permanent phrenic nerve paralysis, pulmonary edema, severe pericarditis, significant effusion/tamponade, stroke/CVA, systemic/pulmonary embolism needing intervention, TIA, vagal nerve injury causing esophageal dysmotility/gastroparesis, vascular access complications needing intervention, AKI needing dialysis or hospitalization \>48h or prolonged \>48h, death, any device/procedure-related CV/pulmonary event causing/prolonging hospitalization \>48h (excludes recurrent AF/AT/AFL). Within 3 months: atrioesophageal/esophago-pericardial fistula, esophageal perforation (device/procedure related; excludes TEE/nasogastric tube injury). Within 6 months: pulmonary vein stenosis (≥70% diameter reduction).

  Index ablation procedure through 6 months of follow up.

Secondary Outcomes (2)

• Secondary Endpoint: Quality of Life (AFEQT)

  Index ablation procedure through 12 months of follow up.

• Secondary Endpoint: Quality of Life (EQ-5D)

  Index ablation procedure through 12 months follow up.

Study Arms (1)

Pulmonary Vein Isolation Ablation

EXPERIMENTAL

Pulmonary Vein Isolation Ablation utilizing the Sphere-360 and Affera Mapping and Ablation System

Device: Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System

Interventions

Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System DEVICE

Pulmonary Vein Isolation using the Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System

Pulmonary Vein Isolation Ablation

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• A diagnosis of recurrent symptomatic PAF, which is defined as continuous AF episode lasting longer than 30 seconds but terminates spontaneously or with intervention within 7 days of onset, documented by the following:
• a physician's note indicating at least 2 symptomatic PAF episodes occurring within 6 months prior to enrollment; and
• at least 1 electrocardiographically documented episode within 12 months prior to enrollment
• Adults who are ≥18 and ≤80 years of age on the day of enrollment.
• Willing and able to comply with all baseline and follow-up evaluations for the full length of the study.

You may not qualify if:

• Continuous AF lasting more than 7 days. This includes persistent atrial fibrillation (PsAF) (both early or long-standing) by diagnosis or continuous duration \> 7 days
• AF that required three (3) or more distinct cardioversions in the preceding 12 months.
• LA anteroposterior \> 5.0 cm (by MRI, CT, or TTE)
• Any of the following procedures, implants, or conditions at baseline: prior left atrial catheter or surgical ablation, prior left atrial percutaneous interventions including left atrial appendage occlusion, and septal closure devices
• Planned LAA closure procedure 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
• Patient who is not on oral anticoagulation therapy for at least 3 weeks prior to the ablation procedure
• 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)
• Presence of any pulmonary vein stents
• Known pre-existing pulmonary vein stenosis
• Pre-existing hemidiaphragmatic paralysis
• Prior valvular (surgical or percutaneous) procedure including prosthetic, bioprosthetic, valve replacement, valve repair or valvuloplasty, and any prior atriotomy
• Moderate to severe aortic or mitral valve stenosis
• Moderate to severe mitral regurgitation (i.e., 3+ or 4+ MR)
• Any cardiac surgery, myocardial infarction, PCI / PTCA or coronary artery stenting which occurred during the 3-month interval preceding the consent date
• Unstable angina

Sponsors & Collaborators

• Medtronic Cardiac Ablation Solutions: lead

Study Sites (12)

Arrhythmia Research Group

Jonesboro, Arkansas, 72401, United States

RECRUITING

Northwestern University

Chicago, Illinois, 60611, United States

RECRUITING

Massachusetts General Hospital

Boston, Massachusetts, 02114, United States

RECRUITING

Southcoast Health System

Fall River, Massachusetts, 02720, United States

RECRUITING

The Valley Hospital

Paramus, New Jersey, 07652, United States

RECRUITING

Icahn School of Medicine at Mount Sinai

New York, New York, 10029, United States

RECRUITING

Northwell Health Lenox Hill Hospital

New York, New York, 10075, United States

RECRUITING

Atrium Health Wake Forest Baptist Medical Center

Winston-Salem, North Carolina, 27157, United States

RECRUITING

Bethesda North Hospital

Cincinnati, Ohio, 45220, United States

RECRUITING

The Ohio State University Wexner Medical Center

Columbus, Ohio, 43210, United States

RECRUITING

Texas Cardiac Arrhythmia Research Foundation

Austin, Texas, 78705, United States

RECRUITING

Inova Fairfax Hospital

Falls Church, Virginia, 22042, United States

RECRUITING

MeSH Terms

Conditions

Atrial Fibrillation

Condition Hierarchy (Ancestors)

Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Vivek Reddy, MD

  Icahn School of Medicine at Mt Sinai

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Leah Crocker

CONTACT

763-526-6237; leah.c.crocker@medtronic.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 26, 2025
• First Posted: December 30, 2025
• Study Start: January 15, 2026
• Primary Completion (Estimated): November 22, 2027
• Study Completion (Estimated): November 22, 2027
• Last Updated: April 20, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (12)