The Fourth Left Atrial Appendage Occlusion Study

NCT ID: NCT05963698

Last Updated: 2025-12-16

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

RECRUITING

Clinical Phase

NA

Total Enrollment

4000 participants

Study Classification

INTERVENTIONAL

Study Start Date

2023-11-30

Study Completion Date

2029-12-01

Brief Summary

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LAAOS-4 aims to determine if catheter-based endovascular left atrial appendage occlusion prevents ischemic stroke or systemic embolism in participants with atrial fibrillation, who remain at high risk of stroke, despite receiving ongoing treatment with oral anticoagulation.

Detailed Description

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LAAOS-4 is a multicentre, prospective, open-label, randomized controlled trial with blinded assessment of endpoints (PROBE) to determine if catheter-based endovascular left atrial appendage occlusion prevents ischemic stroke or systemic embolism in participants with atrial fibrillation, who remain at high risk of stroke, despite receiving ongoing treatment with oral anticoagulation.

Conditions

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Atrial Fibrillation Stroke, Ischemic Systemic Embolism

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Randomized Controlled Trial
Primary Study Purpose

TREATMENT

Blinding Strategy

SINGLE

Outcome Assessors
Events Adjudication Committee is blinded to intervention assignment.

Study Groups

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WATCHMAN device

Participants will undergo endovascular left atrial appendage occlusion with the WATCHMAN device

Group Type EXPERIMENTAL

WATCHMAN device

Intervention Type DEVICE

Participants will undergo endovascular left atrial appendage occlusion with the WATCHMAN device

Standard Care

Participants will receive local, standard medical care

Group Type NO_INTERVENTION

No interventions assigned to this group

Interventions

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WATCHMAN device

Participants will undergo endovascular left atrial appendage occlusion with the WATCHMAN device

Intervention Type DEVICE

Eligibility Criteria

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Inclusion Criteria

1. (a) Persistent or permanent atrial fibrillation OR (b) Paroxysmal atrial fibrillation in participants with a history of ischemic stroke or systemic embolism
2. Increased risk of stroke, defined as a CHA2DS2-VASc stroke risk score of ≥ 4. \[Note: the acronym CHA2DS2-VASc stands for congestive heart failure, hypertension, age ≥75 (doubled), diabetes, stroke (doubled), vascular disease, age 65 to 74 and sex category (female).\]
3. Treatment with oral anticoagulants (Vitamin K agonist or factor Xa inhibitor) for at least 90 days prior to enrollment, AND no documented plan to discontinue treatment with oral anticoagulants for the expected duration of the trial.

Exclusion Criteria

1. Age \< 18 years
2. Current left atrial appendage thrombus
3. Prior left atrial appendage occlusion or removal (surgical or percutaneous)
4. Prior percutaneous atrial septal defect or patent foramen ovale closure
5. Prior atrial fibrillation ablation unless evidence of recurrent qualifying atrial fibrillation present at least 30 days following ablation
6. Planned atrial fibrillation ablation within 90 days of enrollment
7. Individuals being treated with direct thrombin inhibitors
8. Women of childbearing potential unless they agree to employ effective birth control methods throughout the study
9. Anticipated life-expectancy of \< 2 years
10. Patient unable or willing to give informed consent
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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McMaster University

OTHER

Sponsor Role collaborator

Population Health Research Institute

OTHER

Sponsor Role collaborator

Boston Scientific Corporation

INDUSTRY

Sponsor Role collaborator

Hamilton Health Sciences Corporation

OTHER

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Jeff Healey

Role: PRINCIPAL_INVESTIGATOR

Hamilton Health Sciences Corporation

Locations

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Affinity Hospital dba Grandview Medical Center

Birmingham, Alabama, United States

Site Status WITHDRAWN

Arrhythmia Research Group

Jonesboro, Arkansas, United States

Site Status RECRUITING

Memorial Health Services

Fountain Valley, California, United States

Site Status RECRUITING

Loma Linda University Health

Loma Linda, California, United States

Site Status RECRUITING

Sutter Valley Hospitals dba Sutter Institute for Medical Research

Sacramento, California, United States

Site Status RECRUITING

St. Vincent's Health System

Jacksonville, Florida, United States

Site Status RECRUITING

The University of South Florida

Tampa, Florida, United States

Site Status RECRUITING

Emory University

Atlanta, Georgia, United States

Site Status RECRUITING

St Luke's Regional Medical Center, Ltd

Boise, Idaho, United States

Site Status RECRUITING

Kootenai Health Inc.

Coeur d'Alene, Idaho, United States

Site Status RECRUITING

Northwestern University

Evanston, Illinois, United States

Site Status RECRUITING

Cardiovascular Medicine, PLLC and Unity Point Trinity Rock Island

Rock Island, Illinois, United States

Site Status RECRUITING

Community Health Network Inc.

Indianapolis, Indiana, United States

Site Status RECRUITING

MercyOne Iowa Heart Center

West Des Moines, Iowa, United States

Site Status RECRUITING

University of Kansas Medical Center Research Institute, Inc.

Kansas City, Kansas, United States

Site Status RECRUITING

Babtist Health Lexington

Lexington, Kentucky, United States

Site Status RECRUITING

Ochsner Clinic Foundation

New Orleans, Louisiana, United States

Site Status RECRUITING

University of Maryland Baltimore

Baltimore, Maryland, United States

Site Status RECRUITING

Lahey Clinic Inc.

Burlington, Massachusetts, United States

Site Status RECRUITING

University of Michigan

Ann Arbor, Michigan, United States

Site Status RECRUITING

Henry Ford Health System

Detroit, Michigan, United States

Site Status RECRUITING

Henry Ford Health System

Detroit, Michigan, United States

Site Status RECRUITING

Mayo Clinic

Rochester, Minnesota, United States

Site Status RECRUITING

The Feinstein Institutes for Medical Research

Manhasset, New York, United States

Site Status RECRUITING

Cornell University for and on behalf of its Joan & Sanford I. Weill Medical College and The New York Presbyterian Hospital

New York, New York, United States

Site Status RECRUITING

NYU Grossman School of Medicine

New York, New York, United States

Site Status WITHDRAWN

Mission Hospital HCA

Asheville, North Carolina, United States

Site Status RECRUITING

Aultman Hospital

Canton, Ohio, United States

Site Status RECRUITING

TriHealth Inc.

Cincinnati, Ohio, United States

Site Status RECRUITING

Cleveland Clinic

Cleveland, Ohio, United States

Site Status RECRUITING

The Pennsylvania State University and The Milton S. Hershey Medical Center

Hershey, Pennsylvania, United States

Site Status RECRUITING

The Trustees of the University of Pennsylvania

Philadelphia, Pennsylvania, United States

Site Status RECRUITING

University of Pittsburgh Medical Center (UPMC) Presbyterian Heart and Vascular Institute

Pittsburgh, Pennsylvania, United States

Site Status RECRUITING

Rhode Island Hospital

Providence, Rhode Island, United States

Site Status RECRUITING

Glanecare, Inc. d/b/a HCA Florida Brandon Hospital

Brentwood, Tennessee, United States

Site Status RECRUITING

Texas Cardiac Arrhythmia Research Foundation

Austin, Texas, United States

Site Status WITHDRAWN

Baylor Research Institute

Dallas, Texas, United States

Site Status RECRUITING

Heart Rhythm Associates

The Woodlands, Texas, United States

Site Status WITHDRAWN

CHRISTUS Northeast Texas Health System

Tyler, Texas, United States

Site Status RECRUITING

The Rector and Visitors of the University of Virginia

Charlottesville, Virginia, United States

Site Status RECRUITING

CommonSpirit Health Research Institute

Tacoma, Washington, United States

Site Status RECRUITING

The Medical College of Wisconsin

Milwaukee, Wisconsin, United States

Site Status RECRUITING

Imeldaziekenhuis

Bonheiden, Antwerpen, Belgium

Site Status RECRUITING

AZORG vzw and Hartcentrum Aalst

Aalst, East-Flanders, Belgium

Site Status RECRUITING

ASBL CHU Helora - Hôpital de La Louvière - site Jolimont

La Louvière, Hainaut, Belgium

Site Status RECRUITING

CHR de la Citadelle

Liège, Liège, Belgium

Site Status RECRUITING

AZ Glorieux

Ronse, Oost-Vlaanderen, Belgium

Site Status RECRUITING

AZ Delta VZW

Roeselare, West-Vlaanderen, Belgium

Site Status RECRUITING

Universitair Ziekenhuis Brussel

Brussels, , Belgium

Site Status RECRUITING

University of Calgary

Calgary, Alberta, Canada

Site Status RECRUITING

Vancouver Coastal Health Authority

Vancouver, British Columbia, Canada

Site Status RECRUITING

St. Boniface Hospital Inc.

Winnipeg, Manitoba, Canada

Site Status RECRUITING

Circulate Cardiac & Vascular Centre (CCVC)

Burlington, Ontario, Canada

Site Status RECRUITING

Cambridge Cardiac Care Inc.

Cambridge, Ontario, Canada

Site Status RECRUITING

Hamilton Health Sciences Corp

Hamilton, Ontario, Canada

Site Status RECRUITING

Research St. Joseph's - Hamilton

Hamilton, Ontario, Canada

Site Status RECRUITING

Waterloo Wellington Cardiovascular Research Institute (WWCRI)

Kitchener, Ontario, Canada

Site Status RECRUITING

Lawson Health Research Institute

London, Ontario, Canada

Site Status RECRUITING

Southlake Regional Health Centre

Newmarket, Ontario, Canada

Site Status RECRUITING

Partners in Advanced Cardiac Evaluation (PACE)

Newmarket, Ontario, Canada

Site Status RECRUITING

Ottawa Heart Institute Research Corp

Ottawa, Ontario, Canada

Site Status RECRUITING

Niagara Health System - Niagara Falls

St. Catharines, Ontario, Canada

Site Status RECRUITING

Niagara Health Systems - St. Catharines

St. Catharines, Ontario, Canada

Site Status RECRUITING

Sunnybrook Health Sciences Center

Toronto, Ontario, Canada

Site Status RECRUITING

Lawrence Park Cardiology

Toronto, Ontario, Canada

Site Status RECRUITING

Unity Health Toronto

Toronto, Ontario, Canada

Site Status RECRUITING

Institut de Cardiologie de Montreal (ICM)

Montreal, Quebec, Canada

Site Status RECRUITING

Centre hospitalier de l'Université de Montréal

Montreal, Quebec, Canada

Site Status RECRUITING

Institut universitaire de cardiologie et de pneumologie de Québec-Université Laval

Québec, Quebec, Canada

Site Status RECRUITING

Centre intégré universitaire de santé et de services sociaux de l'Estrie - Centre hospitalier universitaire de Sherbrooke (CIUSSS de l'Estrie - CHUS)

Sherbrooke, Quebec, Canada

Site Status RECRUITING

Prairie Valscular Research Inc. (PVRI)

Regina, Saskatchewan, Canada

Site Status RECRUITING

Saskatchewan Health Authority

Saskatoon, Saskatchewan, Canada

Site Status RECRUITING

Region Hospital Viborg

Viborg, Central Jutland, Denmark

Site Status RECRUITING

Aarhus University Hospital (AUH)

Aarhus, Region Midt, Denmark

Site Status RECRUITING

Esbjerg & Grindsted Hospital - University Hospital of Southern Denmark

Esbjerg, Region Syddanmark, Denmark

Site Status RECRUITING

North Denmark Regional Hospital

Hjørring, , Denmark

Site Status RECRUITING

Odense Universitets Hospital

Odense C, , Denmark

Site Status RECRUITING

Infirmerie Protestante de Lyon

Caluire-et-Cuire, Auvergne-Rhône-Alpes, France

Site Status RECRUITING

Clinique Pasteur

Toulouse, Occitanie, France

Site Status RECRUITING

Hôpital Bichat

Paris, , France

Site Status RECRUITING

European Georges Pompidou Hospital

Paris, , France

Site Status RECRUITING

Centre Cardiologique due Nord

Saint-Denis, , France

Site Status RECRUITING

Städtisches Klinikum Karsruhe gGmbH

Karlsruhe, Baden-Wurttemberg, Germany

Site Status RECRUITING

CVC Rhein-Main GmbH

Frankfurt am Main, Hesse, Germany

Site Status RECRUITING

MVZ CCB Frankfurt und Main-Taunus GbR

Frankfurt am Main, Hesse, Germany

Site Status RECRUITING

Johann Wolfgang Goethe Universität Franfurt - Universitätsklinikum Franfurt

Frankfurt am Main, Hesse, Germany

Site Status RECRUITING

Krankenhausbetriebsgesellschaft Bad Oeynhausen mbH

Bad Oeynhausen, North Rhine-Westphalia, Germany

Site Status RECRUITING

Westpfalz-Klinikum GmbH

Kaiserslautern, Rhineland-Palatinate, Germany

Site Status RECRUITING

Herzzentrum Leipzig GmbH

Leipzig, Saxony, Germany

Site Status RECRUITING

Universitätsklinikum Schleswig - Holstein

Lübeck, Schleswig-Holstein, Germany

Site Status RECRUITING

Katholisches Krankenhaus "St. Johann Nepomuk"

Erfurt, Thuringia, Germany

Site Status RECRUITING

Charité Universitätsmedizin Berlin

Berlin, , Germany

Site Status RECRUITING

Charité - Universitätsmedizin Berlin

Berlin, , Germany

Site Status RECRUITING

Asklepios Kliniken Hamburg GmbH

Hamburg, , Germany

Site Status RECRUITING

Asklepios Kliniken Hamburg GmbH

Hamburg, , Germany

Site Status RECRUITING

Universitätsklinikum Hamburg-Eppendorf (UKE)

Hamburg, , Germany

Site Status RECRUITING

Universitätsklinikum Heidelberg

Heidelberg, , Germany

Site Status RECRUITING

Fondazione Poliambulanza Istituto Ospedaliero

Brescia, , Italy

Site Status RECRUITING

American Heart of Poland SA

Ustroń, , Poland

Site Status RECRUITING

Hospital Álvaro Cunqueiro

Vigo, Pontevedra, Spain

Site Status RECRUITING

Complejo Asistencial Universitario de León

León, , Spain

Site Status RECRUITING

Universitario La Luz - Grupo Quirónsalud

Madrid, , Spain

Site Status RECRUITING

Hospital Clínico Universitario de Valladolid

Valladolid, , Spain

Site Status RECRUITING

University Hospitals of Leicester NHS Trust

Leicester, Leicestershire, United Kingdom

Site Status RECRUITING

Oxford University Hospitals NHS Foundation Trust

Oxford, Oxfordshire, United Kingdom

Site Status RECRUITING

University Hospitals Coventry and Warwickshire

Coventry, West Midlands, United Kingdom

Site Status RECRUITING

University Hospitals Sussex NHS Trust

Worthing, West Sussex, United Kingdom

Site Status RECRUITING

Liverpool Heart and Chest Hospital NHS Foundation Trust

Liverpool, , United Kingdom

Site Status RECRUITING

Countries

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United States Belgium Canada Denmark France Germany Italy Poland Spain United Kingdom

Central Contacts

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Program Director

Role: CONTACT

905-521-2100

References

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Grifoni E, Pagni B, Sansone T, Baldini M, Bertini E, Giannoni S, Di Donato I, Sivieri I, Iandoli G, Mannini M, Giglio E, Vescera V, Brai E, Signorini I, Cosentino E, Micheletti I, Cioni E, Pelagalli G, Dei A, Giordano A, Dainelli F, Romagnoli M, Mattaliano C, Schipani E, Murgida GS, Di Martino S, Francolini V, Masotti L. Clinical Features, Management, and Recurrence of Acute Ischemic Stroke Occurring in Patients on Oral Anticoagulant Treatment for Nonvalvular Atrial Fibrillation: A Real-World Retrospective Study. Neurologist. 2024 Nov 1;29(6):329-338. doi: 10.1097/NRL.0000000000000579.

Reference Type DERIVED
PMID: 39344366 (View on PubMed)

Other Identifiers

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LAAOS-4

Identifier Type: -

Identifier Source: org_study_id