Preventing atrial fibrillation with surgical ablation and left atrial appendage clipping during heart surgery
Official title: EnCompass Clamp and the AtriClip in Box Lesion and Left Atrial Appendage EXclusion Procedure for the Prevention of New Onset of Atrial Fibrillation
Run by AtriCure, Inc. · NCT06989775 · Data updated 2026-11-12
This trial tests whether adding surgical ablation and clipping of the left atrial appendage during routine open-heart surgery can prevent postoperative and later atrial fibrillation in older patients at higher stroke risk.
Quick facts
| Study type | Interventional |
|---|---|
| Ages | 65 Years and up |
| Sex | All |
| Enrollment | 960 (estimated) |
| Sponsor | AtriCure, Inc. Industry-sponsored |
| Locations | 37 sites (Scottsdale, Arizona and 36 other locations) |
| Status | Recruiting |
| Started | October 24, 2025 |
| Main results expected | February 2027 |
| Study ends | December 2029 |
| Registry record updated | October 7, 2026 |
| Trial ID | NCT06989775 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are patients aged 65 or older with CHA2DS2-VASc ≥ 3 who are scheduled for cardiac surgery requiring cardiopulmonary bypass and opening of the pericardium and who have no prior history of AF or prior pericardial procedures.
✕Probably not a fit
Patients with any prior documented atrial fibrillation or flutter, prior LAA exclusion, off-pump surgery, prior pericardial opening, or other exclusionary conditions (for example infiltrative cardiomyopathy, active infection, NYHA class IV, or ventricular arrhythmia) are not expected to benefit from this prophylactic approach.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
BoxX-NoAF randomizes patients without prior atrial fibrillation who are undergoing cardiac surgery with cardiopulmonary bypass to receive prophylactic left atrial ablation plus left atrial appendage (LAA) exclusion or to usual surgical care. The intervention uses the Isolator® Synergy™ EnCompass® Ablation System for lesion creation and the AtriClip® device for LAA exclusion at the time of the index operation. Patients are enrolled at several US centers and followed for postoperative AF and longer-term clinical atrial fibrillation outcomes. The trial targets older patients with elevated CHA2DS2-VASc scores who are at higher risk of developing AF but have not previously had AF or undergone pericardial surgery.
Why it matters
Potential benefit: If successful, this approach could reduce the rate of postoperative AF and lower long-term atrial fibrillation-related complications such as stroke and readmission.
How similar studies have gone: Surgical ablation and LAA exclusion have shown benefit for patients with existing AF, but prophylactic ablation and LAA exclusion in patients without prior AF is relatively novel and has limited direct evidence to date.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Planned and clinically indicated for cardiac surgical procedure requiring cardiac bypass and opening of the pericardium * Age ≥ 65 years and CHA2DS2-VASc ≥ 3 Exclusion Criteria: * Documented history of atrial fibrillation or atrial flutter anytime prior to the cardiac surgery * Prior procedure involving opening the pericardium or entering the pericardial space * Patients undergoing off-pump surgery * Prior LAA occlusion, exclusion, or removal (surgical or percutaneous) * Presence of a permanent pacemaker * Infiltrative cardiomyopathies (i.e. amyloidosis) * Planned cardiac surgical procedure using non-sternotomy approaches * Patients whose planned procedure is a heart transplant or implantation of any long-term ventricular assist devices * Presence of ventricular arrhythmia * Active endocarditis * NYHA Class IV heart failure symptoms * Preoperative need for an intra-aortic ballon pump or intravenous inotropes * Active systemic infection at the time of cardiac surgery requiring antibiotics * Known allergy to Nitinol or nickel sensitivity * Known medical condition with expected survival of less than 1 year * Other comorbidities that in the Investigator's opinion make the subject unsuitable candidate to complete the protocol required intervention or visits * Current enrollment in an investigation or trial or an investigational devices or investigational drug that would interfere with this trial * Mental impairment or other psychiatric conditions which may not allow the patient to understand the nature, significance, and scope of the trial. * Pregnancy * Known severe symptomatic carotid disease
Where it's running
-
Honor Health
Scottsdale, Arizona, United States Recruiting -
St. Bernards Medical Center
Jonesboro, Arkansas, United States Recruiting -
Sharp Memorial Hospital
San Diego, California, United States Recruiting -
Adventist Health St. Helena
St. Helena, California, United States Recruiting -
Morton Plant Hospital - BayCare Health System, Inc.
Clearwater, Florida, United States Recruiting -
St. Joseph's Hospital - BayCare Health System, Inc.
Clearwater, Florida, United States Recruiting
Show 31 more locations
-
Naples Comprehensive Health
Naples, Florida, United States Recruiting -
Orlando Health, Inc.
Orlando, Florida, United States Recruiting -
Sarasota Memorial Hospital
Sarasota, Florida, United States Recruiting -
Emory University
Atlanta, Georgia, United States Recruiting -
Piedmont Hospital
Atlanta, Georgia, United States Recruiting -
Wellstar Health System
Marietta, Georgia, United States Recruiting -
Northwestern Memorial Hospital
Chicago, Illinois, United States Recruiting -
Norton Healthcare
Louisville, Kentucky, United States Recruiting -
MedStar Health Research Institute
Baltimore, Maryland, United States Recruiting -
University of Michigan
Ann Arbor, Michigan, United States Recruiting -
Corewell Health
Grand Rapids, Michigan, United States Recruiting -
Trinity Health
Ypsilanti, Michigan, United States Recruiting -
Mayo Clinic
Rochester, Minnesota, United States Recruiting -
BJC Healthcare (Washington University)
St Louis, Missouri, United States Recruiting -
Northwell Health
Manhasset, New York, United States Recruiting -
Bethesda North Hospital
Cincinnati, Ohio, United States Recruiting -
Cleveland Clinic Foundation
Cleveland, Ohio, United States Recruiting -
Promedica Toledo Hospital
Toledo, Ohio, United States Recruiting -
Allegheny-Singer Research Institute
Pittsburgh, Pennsylvania, United States Recruiting -
Centennial Medical Center
Nashville, Tennessee, United States Recruiting -
Ascension Saint Thomas
Nashville, Tennessee, United States Recruiting -
St David's HealthCare
Austin, Texas, United States Recruiting -
Baylor Research Institute - Baylor Scott and White Research Institute
Dallas, Texas, United States Recruiting -
Charleston Area Medical Center
Charleston, West Virginia, United States Recruiting -
Aspirus Hospital
Wausau, Wisconsin, United States Recruiting -
Royal Columbian Hospital
New Westminster, British Columbia, Canada Recruiting -
Hamilton General Hospital
Hamilton, Ontario, Canada Recruiting -
London Health Sciences Centre, University Hospital
London, Ontario, Canada Recruiting -
Montreal Heart Institute
Montreal, Quebec, Canada Recruiting -
New York Presbyterian Hospital/Columbia University Irving Medical Center
New York, New York, United States Not yet recruiting -
Methodist San Antonio
San Antonio, Texas, United States Withdrawn
Study contacts
- Study coordinator: BoxX-NoAF Trial Inbox
- Email: BoxXNoAF@atricure.com
- Phone: 1 (513) 755-4100
Similar studies
Other studies for the same condition or treatment. Recruiting studies are listed first.
-
Colchicine to lower inflammation and prevent atrial fibrillation after coronary bypass
This trial tests whether giving colchicine to adults having coronary artery bypass (CABG) can lower inflammation and reduce the chance of atrial fibrillation after surgery.
-
Investigating Atrial Fibrillation After Heart Surgery
This study looks at how common irregular heartbeats are after heart surgery and what factors might increase the risk for patients in Thailand.
-
Using amiodarone patches to prevent irregular heart rhythms after heart surgery
This study is testing if using amiodarone patches during heart surgery can help prevent irregular heart rhythms in patients aged 20-85.
How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.