Clinical trial No longer in our active list Interventional Ages 18 and up

Comparing Amulet LAA occluder to NOAC therapy for atrial fibrillation patients

Official title: Clinical Trial of Atrial Fibrillation Patients Comparing Left Atrial Appendage Occlusion Therapy to Non-vitamin K Antagonist Oral Anticoagulants

Run by Abbott Medical Devices · NCT04226547 · Data updated 2026-05-14

This study is no longer in our active list. It may have stopped recruiting or finished. The details below are as of 2026-05-14 and are kept for reference. Check ClinicalTrials.gov for its current status, or see similar studies below.

This study tests whether the Amulet LAA occluder device is safer and more effective than blood-thinning medications for people with atrial fibrillation who are at risk for strokes.

More Stroke trials

Quick facts

Study typeInterventional
Ages18 Years and up
SexAll
Enrollment2650 (estimated)
SponsorAbbott Medical Devices
Industry-sponsored
Locations132 sites (Birmingham, Alabama and 131 other locations)
Trial IDNCT04226547 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates are adults aged 18 and older with documented non-valvular atrial fibrillation and a CHA2DS2-VASc score indicating a high risk of stroke.

Probably not a fit

Patients who require long-term oral anticoagulation therapy for conditions other than atrial fibrillation may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This trial aims to assess the safety and effectiveness of the Amulet LAA occluder device compared to non-vitamin K oral anticoagulants (NOACs) in patients with non-valvular atrial fibrillation who are at increased risk for ischemic stroke. Participants will be randomly assigned in a 1:1 ratio to receive either the Amulet device or a NOAC, with the specific NOAC chosen at the discretion of the study physician. The study is designed as a prospective, multicenter trial conducted worldwide, focusing on long-term outcomes for patients requiring anticoagulation therapy.

Why it matters

Potential benefit: If successful, this study could provide a safer and more effective alternative to long-term NOAC therapy for patients with atrial fibrillation.

How similar studies have gone: Other studies have shown promise in using left atrial appendage occlusion devices, suggesting potential success for this approach.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Documented paroxysmal, persistent, or permanent non-valvular AF (documentation must include an electrocardiogram, Holter, or event recorder)
* At high risk of stroke or systemic embolism, defined as a CHA2DS2-VASc score of ≥ 2 for men and ≥ 3 for women
* Eligible for long-term NOAC therapy
* Able to comply with the required NOAC medication regimen if randomized to the Control Group
* Able to comply with the required medication regimen post-device implant if subject is randomized to the Device Group or subject is a Roll-in
* Able to understand, and is willing to provide, written informed consent to participate in the trial, prior to any clinical investigation related procedure or assessment
* 18 years of age or older, or the age of legal consent
* Able and willing to return for required follow-up visits and assessments

Exclusion Criteria:

* Requires long-term OAC therapy for a condition other than AF
* Planned cardiac intervention or surgery, which is invasive or requires sedation or anesthesia, within 3 months following randomization, other than study-related procedures such as LAAO and cardiac imaging (if applicable)
* Known contraindication to, or allergic to, aspirin, clopidogrel, or OAC medication use
* Indicated for P2Y12 platelet inhibitor for \>1 year post-randomization
* In the opinion of the investigator, is considered at high risk for general anesthesia and general anesthesia is planned for the study procedure
* Has undergone atrial septal defect (ASD) repair or has an ASD closure device present
* Has undergone patent foramen ovale (PFO) repair or has a PFO closure device implanted
* Is implanted with a mechanical valve prosthesis
* Is implanted with an inferior vena cava filter
* History of rheumatic or congenital mitral valve heart disease
* Has any of the customary contraindications for a percutaneous catheterization procedure (e.g. subject is too small to accommodate the ICE probe (if planned) or required catheters, or subject has active infection or bleeding disorder)
* Customary contraindications for TEE/TOE (e.g., presence of esophageal varices, esophageal stricture, or history of esophageal cancer)
* Experienced stroke or transient ischemic attack (TIA) within 90 days prior to randomization or implant procedure (as applicable)
* Underwent any cardiac or non-cardiac intervention or surgery within 30 days prior to randomization
* Underwent catheter ablation for AF or atrial flutter within 60 days prior to randomization
* Experienced myocardial infarction within 90 days prior to randomization
* New York Heart Association Class IV Congestive Heart Failure
* Left ventricular ejection fraction ≤ 30% (per most recent assessment)
* Symptomatic carotid disease (defined as \> 50% lumen diameter narrowing on CTA, MRA, or TCD with symptoms of ipsilateral transient or visual TIA evidenced by amaurosis fugax, ipsilateral hemispheric TIAs or ipsilateral stroke); if subject has a history of carotid stent or endarterectomy the subject is eligible if there is \< 50% lumen diameter narrowing
* Has known intracranial atherosclerosis and/or intracranial small vessel disease (defined as 6 points on the Fazekas Scale)
* Reversible cause of AF (i.e., secondary to thyroid disorders, acute alcohol intoxication, trauma, recent major surgical procedures)
* History of idiopathic or recurrent venous thromboembolism
* LAA is obliterated or surgically ligated
* Thrombocytopenia (defined as \< 50,000 platelets per microliter (\<50 x 10\^9 /L)or anemia (defined as hemoglobin \< 10 g/dL) requiring transfusions
* Hypersensitivity to any portion of the device material or individual components of the Amulet LAA occluder device (e.g., nickel allergy)
* Actively enrolled in, or plans to enroll in, a concurrent clinical study in which the active treatment arm may confound the results of this trial
* Is pregnant or breastfeeding, or pregnancy is planned during the course of the investigation
* Active endocarditis or other infection producing bacteremia
* Transient case of AF (i.e., never previously detected, provoked/induced by surgical or catheter manipulations, etc.)
* Severe renal failure (estimated glomerular filtration rate \<30 ml/min/1.73m2), but not on dialysis
* Life expectancy is less than 2 years in the opinion of the Investigator
* Presence of other anatomic or comorbid conditions, or other medical, social, or psychological conditions that, in the Investigator's opinion, could limit the subject's ability to participate in the clinical investigation or to comply with follow up requirements, or impact the scientific soundness of the clinical investigation results.

Where it's running

  • University Hospital - Univ. of Alabama at Birmingham (UAB)
    Birmingham, Alabama, United States
    Recruiting
  • Heart Center Research, LLC
    Huntsville, Alabama, United States
    Recruiting
  • Arizona Cardiovascular Research Center
    Phoenix, Arizona, United States
    Recruiting
  • Tucson Medical Center
    Tucson, Arizona, United States
    Recruiting
  • Arrhythmia Research Group
    Jonesboro, Arkansas, United States
    Recruiting
  • Scripps Health
    La Jolla, California, United States
    Recruiting
Show 44 more locations
  • Kaiser Permanente Los Angeles Medical Center
    Los Angeles, California, United States
    Recruiting
  • Huntington Memorial Hospital
    Pasadena, California, United States
    Recruiting
  • Mercy Medical Group - Cardiology
    Sacramento, California, United States
    Recruiting
  • MedStar Washington Hospital Center
    Washington, District of Columbia, United States
    Recruiting
  • AdventHealth Florida Cardiology - Altamonte Springs
    Altamonte Springs, Florida, United States
    Recruiting
  • St. Vincent's Medical Center
    Jacksonville, Florida, United States
    Recruiting
  • Baptist Medical Center
    Jacksonville, Florida, United States
    Recruiting
  • AdventHealth Florida Cardiology - Lake Mary
    Lake Mary, Florida, United States
    Recruiting
  • NCH Healthcare System
    Naples, Florida, United States
    Recruiting
  • AdventHealth Orlando
    Orlando, Florida, United States
    Recruiting
  • AdventHealth Florida Cardiology - Oviedo
    Oviedo, Florida, United States
    Recruiting
  • Sarasota Memorial Hospital
    Sarasota, Florida, United States
    Recruiting
  • Piedmont Heart Institute
    Atlanta, Georgia, United States
    Recruiting
  • Emory University Hospital
    Atlanta, Georgia, United States
    Recruiting
  • Northside Hospital
    Atlanta, Georgia, United States
    Recruiting
  • St. Joseph's Hospital
    Atlanta, Georgia, United States
    Recruiting
  • Northside Hospital (CardioVascular Group Lawrenceville)
    Lawrenceville, Georgia, United States
    Recruiting
  • Northwestern Memorial Hospital
    Chicago, Illinois, United States
    Recruiting
  • Central DuPage Hospital
    Winfield, Illinois, United States
    Recruiting
  • Lutheran Hospital of Indiana
    Fort Wayne, Indiana, United States
    Recruiting
  • Kansas University Medical Center
    Kansas City, Kansas, United States
    Recruiting
  • Kansas City Cardiac Arrhythmia Research Foundation
    Overland Park, Kansas, United States
    Recruiting
  • Overland Park Mid America Cardiology
    Overland Park, Kansas, United States
    Recruiting
  • Via Christi Regional Medical Center - St. Francis Campus
    Wichita, Kansas, United States
    Recruiting
  • Baptist Health Lexington
    Lexington, Kentucky, United States
    Recruiting
  • Our Lady of the Lake Physician Group
    Baton Rouge, Louisiana, United States
    Recruiting
  • Cardiovascular Institute of the South
    Houma, Louisiana, United States
    Recruiting
  • MedStar Union Memorial Hospital
    Baltimore, Maryland, United States
    Recruiting
  • Tufts Medical Center
    Boston, Massachusetts, United States
    Recruiting
  • Beth Israel Deaconess Medical Center
    Boston, Massachusetts, United States
    Recruiting
  • Spectrum Health Butterworth Hospital
    Grand Rapids, Michigan, United States
    Recruiting
  • VA Medical Center Minneapolis
    Minneapolis, Minnesota, United States
    Recruiting
  • St. Cloud Hospital - Central MN Heart Clinic
    Saint Cloud, Minnesota, United States
    Recruiting
  • Jackson Heart Clinic
    Jackson, Mississippi, United States
    Recruiting
  • Bryan Heart
    Lincoln, Nebraska, United States
    Recruiting
  • CHI Health Creighton University Medical Center-Bergan Mercy
    Omaha, Nebraska, United States
    Recruiting
  • Cooper University Hospital
    Camden, New Jersey, United States
    Recruiting
  • New Mexico Heart Institute
    Albuquerque, New Mexico, United States
    Recruiting
  • South Shore University Hospital-Northwell
    Bay Shore, New York, United States
    Recruiting
  • Buffalo General Hospital
    Buffalo, New York, United States
    Recruiting
  • Mount Sinai Hospital
    New York, New York, United States
    Recruiting
  • New York Presbyterian Hospital/Cornell University
    New York, New York, United States
    Recruiting
  • Staten Island University Hospital Northwell
    Staten Island, New York, United States
    Recruiting
  • Mission Health & Hospitals
    Asheville, North Carolina, United States
    Recruiting

+82 more sites. See ClinicalTrials.gov for the full list.

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.