Paroxysmal AFHorizon 360NCT07308847
Horizon 360 Protocol for the Treatment of Paroxysmal Atrial Fibrillation With the Sphere-360™ Catheter and Affera™ Mapping and Ablation System (Horizon 360)
A study testing Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System in people with Paroxysmal AF, run by Medtronic Cardiac Ablation Solutions at 24 sites in United States.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Paroxysmal AF
- What is being tested?
- Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 300 participants
- Where
- 24 sitesUnited States
- Study dates
- 15 Jan 2026to 30 Sep 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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
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- 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
- NYHA Class III or IV congestive heart failure or documented left ventricular ejection fraction (LVEF) less than or equal to 40% measure by acceptable cardiac testing (e.g. TTE), or planned transplant or left ventricular assist device (LVAD)
- Severe lung disease, primary pulmonary hypertension, or any lung disease with abnormal blood gases or requiring supplemental oxygen
- Rheumatic heart disease
- Severe thrombocytosis, thrombocytopenia, or any bleeding or clotting disorder
- Contraindication to or unwillingness to use systemic anticoagulation
- Documented left atrial thrombus on imaging
- Active systemic infection or sepsis
- Hypertrophic cardiomyopathy
- Known reversible causes of AF, including but not limited to uncontrolled hyperthyroidism, severe untreated obstructive sleep apnea, and acute alcohol toxicity
- Any cerebral ischemic event (strokes or TIAs) which occurred during the 6-month interval preceding the consent date
- Carotid stenting or endarterectomy
- History of thromboembolic event within the past 6 months or evidence of intracardiac thrombus at the time of the procedure
- 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
- Patient with life expectancy that makes it unlikely 12 months of follow-up will be completed
- Current or anticipated participation in any other clinical trial of a drug, device or biologic during the duration of the study not pre-approved by Medtronic
- Known allergies or hypersensitivities to adhesives
- Body mass index > 40 kg/m2
- Atrial myxoma
- Significant restrictive or obstructive pulmonary disease or chronic respiratory condition.
- 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
- Solid organ or hematologic transplant, or currently being evaluated for an organ transplant
- Presence of intramural thrombus, tumor, or other abnormality that precludes vascular access, catheter introduction, or manipulation
- Known drug or alcohol dependency
- Significant congenital anomaly or medical problem that, in the opinion of the investigator, would preclude enrollment in this study or compliance with follow-up requirements or would impact the scientific soundness of the clinical trial results.
- Treatment with Amiodarone within the 3 months prior to enrollment
- Amyloid heart disease (cardiac amyloidosis)
Trial locations and contacts
24 sites in 1 country.
24 sites in 1 country
United States24 sites
Texas Cardiac Arrhythmia Research Foundation
Austin, Texas, 78705
Massachusetts General Hospital
Boston, Massachusetts, 02114
Medical University of South Carolina
Charleston, South Carolina, 29425
Northwestern University
Chicago, Illinois, 60611
Bethesda North Hospital
Cincinnati, Ohio, 45220
Cleveland Clinic Foundation
Cleveland, Ohio, 44195
The Ohio State University Wexner Medical Center
Columbus, Ohio, 43210
Ohio Health Research and Innovation Institute
Columbus, Ohio, 43214-3907
Duke University Medical Center
Durham, North Carolina, 27710
Southcoast Health System
Fall River, Massachusetts, 02720
Inova Fairfax Hospital
Falls Church, Virginia, 22042
Arrhythmia Research Group
Jonesboro, Arkansas, 72401
Scripps Memorial Hospital
La Jolla, California, 92037
Minneapolis Heart Institute Foundation
Minneapolis, Minnesota, 55407
NCH Rooney Heart Institute
Naples, Florida, 34102
Icahn School of Medicine at Mount Sinai
New York, New York, 10029
Northwell Health Lenox Hill Hospital
New York, New York, 10075
Sentara Norfolk General Hospital
Norfolk, Virginia, 23507
Kansas City Heart Rhythm Institute (Midwest Heart and Vascular Specialist)
Overland Park, Kansas, 66211
The Valley Hospital
Paramus, New Jersey, 07652
Mayo Clinic
Rochester, Minnesota, 55902
Mercy General Hospital
Sacramento, California, 95819
Memorial Health University Medical Center
Savannah, Georgia, 31404
Atrium Health Wake Forest Baptist Medical Center
Winston-Salem, North Carolina, 27157
About this study
Official title: Horizon 360 Protocol for the Treatment of Paroxysmal Atrial Fibrillation With the Prospective, Single Arm, Unblinded Pre-market Clinical Study to Evaluate the Safety and Effectiveness of the Sphere-360 Catheter and Affera Mapping and Ablation System for Treating Paroxysmal Atrial Fibrillation (PAF)
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
- Being tested
- Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System
- Keywords
- Paroxysmal Atrial Fibrillation, Atrial Fibrillation, Pulsed Field Ablation
- Medical subject headings
- Atrial Fibrillation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation SystemDevice
Pulmonary Vein Isolation using the Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System
| Study group | Role | What they receive |
|---|---|---|
| Pulmonary Vein Isolation Ablation | Experimental | Pulmonary Vein Isolation Ablation utilizing the Sphere-360 and Affera Mapping and Ablation System Receives: Device: Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 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).
Measured: Index ablation procedure through 6 months of follow up.
Secondary outcomes (2)
Secondary Endpoint: Quality of Life (AFEQT)
Change in AFEQT score from baseline to 12 months. The AFEQT is an AF-specific health-related quality of life questionnaire, scored 0-100 (higher scores indicate better quality of life).
Measured: Index ablation procedure through 12 months of follow up.
Secondary Endpoint: Quality of Life (EQ-5D)
Change in EQ-5D composite score from baseline to 12 months. The EQ-5D is a standardized instrument for generic health status, with composite scores indexed to a US reference population.
Measured: Index ablation procedure through 12 months follow up.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Dec 2025
- Study start15 Jan 2026
- Primary completion30 Sep 2027 (estimated)
- Study completion30 Sep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Paroxysmal AFStudies of the same condition, open and under way.
- More trials run by Medtronic Cardiac Ablation SolutionsThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 300 participants (actual)
Sponsor and investigators
- Lead sponsor
- Medtronic Cardiac Ablation Solutions
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Vivek Reddy, MD, Principal investigator, Icahn School of Medicine at Mt Sinai
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07308847
- Sponsor's protocol ID
- Horizon 360
- Acronym
- Horizon 360
- Status last verified
- Aug 2026
- First submitted
- 26 Dec 2025
- Last updated
- 6 Nov 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Horizon 360 Protocol for the Treatment of Paroxysmal Atrial Fibrillation With the Prospective, Single Arm, Unblinded Pre-market Clinical Study to Evaluate the Safety and Effectiveness of the Sphere-360 Catheter and Affera Mapping and Ablation System for Treating Paroxysmal Atrial Fibrillation (PAF)
- ClinicalTrials.gov ID
- NCT07308847
- Acronym / sponsor ID
- Horizon 360 / Horizon 360
- Conditions
- Paroxysmal AF
- Keywords
- Paroxysmal Atrial Fibrillation, Atrial Fibrillation, Pulsed Field Ablation
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 300 participants (actual)
- Lead sponsor
- Medtronic Cardiac Ablation SolutionsIndustry (pharma, biotech, devices)
- Study start
- 15 Jan 2026 (actual)
- Primary completion
- 30 Sep 2027 (estimated)
- Study completion
- 30 Sep 2027 (estimated)
- First posted
- 30 Dec 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Pulmonary Vein Isolation Ablation | Experimental | Device: Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation SystemPulmonary Vein Isolation Ablation utilizing the Sphere-360 and Affera Mapping and Ablation System |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- 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:
- 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.
Key exclusion criteria (41 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation SystemPulmonary Vein Isolation using the Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System | Device | Pulmonary Vein Isolation Ablation |
Primary outcome
Freedom from Atrial Tachyarrhythmia Recurrence Through 12 Months Post-Ablation
Time frame: Index ablation procedure through 12 months of follow up.
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.
Incidence of Device- and Procedure-Related Serious Adverse Events Through 6 Months
Time frame: Index ablation procedure through 6 months of follow up.
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).
2 secondary outcomes
Secondary Endpoint: Quality of Life (AFEQT)
Time frame: Index ablation procedure through 12 months of follow up.
Secondary Endpoint: Quality of Life (EQ-5D)
Time frame: Index ablation procedure through 12 months follow up.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Nov 2026.
- Individual participant dataSharing planned: No
Related trials for Paroxysmal AF
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A Study of VARIPULSE Catheter and TRUPULSE Generator With VARIPULSE Pro Software in Participants With PAF or PsAF
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Catheter Ablation Using a Novel Navigation and Imaging System
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Vivek Reddy, MD principal investigator
Icahn School of Medicine at Mt Sinai
24 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Sphere-360 Pulsed Field Ablation Catheter with the Affera Mapping and Ablation System in people with Paroxysmal AF, run by Medtronic Cardiac Ablation Solutions at 24 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 41 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 6 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 24 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Freedom from Atrial Tachyarrhythmia Recurrence Through 12 Months Post-Ablation (time frame: Index ablation procedure through 12 months of follow up.). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Nov 2026.