The Fourth Left Atrial Appendage Occlusion Study
LAAOS-4
1 other identifier
interventional
4,000
11 countries
127
Brief Summary
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.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable atrial-fibrillation
Started Nov 2023
Longer than P75 for not_applicable atrial-fibrillation
127 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
July 5, 2023
CompletedFirst Posted
Study publicly available on registry
July 27, 2023
CompletedStudy Start
First participant enrolled
November 30, 2023
CompletedPrimary Completion
Last participant's last visit for primary outcome
September 1, 2029
ExpectedStudy Completion
Last participant's last visit for all outcomes
December 1, 2029
March 12, 2026
September 1, 2025
5.8 years
July 5, 2023
March 10, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Ischemic stroke or systemic embolism
The primary efficacy variable is the time from randomization to first occurrence of any of the components of the composite outcome (adjudicated) over the duration of follow-up, including: * Ischemic stroke (Strokes of undetermined etiology will be treated as ischemic stroke) * Systemic embolism
The study duration is event-driven. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
Secondary Outcomes (6)
All-cause stroke or systemic embolism
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
All-cause stroke, systemic embolism, or transient ischemic attack (TIA)
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
Montreal Cognitive Assessment (MoCA) Score
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
New disabling ischemic strokes
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
Cardiovascular mortality
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
- +1 more secondary outcomes
Other Outcomes (7)
Non-procedural Major Bleeding
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
Hospitalization for any cause
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
Heart failure hospitalization or emergency department/clinic visit for intensification of heart failure related therapy
Will be evaluated once primary outcome meets statistical significance. The primary analysis will be performed through study completion, once 265 primary efficacy endpoint events have occurred (an estimated average follow-up of 4 years).
- +4 more other outcomes
Study Arms (2)
WATCHMAN device
EXPERIMENTALParticipants will undergo endovascular left atrial appendage occlusion with the WATCHMAN device
Standard Care
NO INTERVENTIONParticipants will receive local, standard medical care
Interventions
Participants will undergo endovascular left atrial appendage occlusion with the WATCHMAN device
Eligibility Criteria
You may qualify if:
- (a) Persistent or permanent atrial fibrillation OR (b) Paroxysmal atrial fibrillation in participants with a history of ischemic stroke or systemic embolism
- Increased risk of stroke, defined as a CHA2DS2-VASc stroke risk score of ≥ 4. \[Note: the acronym CHA2DS2-VASc stands for congestive heart failure, hypertension, age ≥75 (doubled), diabetes, stroke (doubled), vascular disease, age 65 to 74 and sex category (female).\]
- 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.
You may not qualify if:
- Age \< 18 years
- Current left atrial appendage thrombus
- Prior left atrial appendage occlusion or removal (surgical or percutaneous)
- Prior percutaneous atrial septal defect or patent foramen ovale closure
- Prior atrial fibrillation ablation unless evidence of recurrent qualifying atrial fibrillation present at least 30 days following ablation
- Planned atrial fibrillation ablation within 90 days of enrollment
- Individuals being treated with direct thrombin inhibitors
- Women of childbearing potential unless they agree to employ effective birth control methods throughout the study
- Anticipated life-expectancy of \< 2 years
- Patient unable or willing to give informed consent
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Hamilton Health Sciences Corporationlead
- McMaster Universitycollaborator
- Population Health Research Institutecollaborator
- Boston Scientific Corporationcollaborator
Study Sites (127)
Affinity Hospital dba Grandview Medical Center
Birmingham, Alabama, 35243, United States
Arrhythmia Research Group
Jonesboro, Arkansas, 72401, United States
Memorial Health Services
Fountain Valley, California, 92708, United States
Loma Linda University Health
Loma Linda, California, 92354, United States
Southern California Permanente Medical Group
Pasadena, California, 91101, United States
Sutter Valley Hospitals dba Sutter Institute for Medical Research
Sacramento, California, 95816, United States
JFK Medical Center Limited Partnership d/b/a HCA Florida JFK Hospital
Atlantis, Florida, 33462, United States
St. Vincent's Health System
Jacksonville, Florida, 32204, United States
Largo Medical Center, Inc. d/b/a HCA Florida Largo Medical Center
Largo, Florida, 33770, United States
The University of South Florida
Tampa, Florida, 33620, United States
Emory University
Atlanta, Georgia, 30322, United States
St Luke's Regional Medical Center, Ltd
Boise, Idaho, 83712, United States
Kootenai Health Inc.
Coeur d'Alene, Idaho, 83814, United States
Northwestern University
Evanston, Illinois, 60208, United States
Cardiovascular Medicine, PLLC and Unity Point Trinity Rock Island
Rock Island, Illinois, 61201, United States
Community Health Network Inc.
Indianapolis, Indiana, 46256, United States
MercyOne Iowa Heart Center
West Des Moines, Iowa, 50266, United States
University of Kansas Medical Center Research Institute, Inc.
Kansas City, Kansas, 66160, United States
Babtist Health Lexington
Lexington, Kentucky, 40503, United States
Ochsner Clinic Foundation
New Orleans, Louisiana, 70121, United States
University of Maryland Baltimore
Baltimore, Maryland, 21201, United States
Lahey Clinic Inc.
Burlington, Massachusetts, 01805, United States
University of Michigan
Ann Arbor, Michigan, 48109, United States
Henry Ford Health System
Detroit, Michigan, 48202, United States
Henry Ford Health System
Detroit, Michigan, 48202, United States
Mayo Clinic
Rochester, Minnesota, 55905, United States
Hackensack University Medical Center
Hackensack, New Jersey, 07601, United States
The Feinstein Institutes for Medical Research
Manhasset, New York, 11030, United States
Cornell University for and on behalf of its Joan & Sanford I. Weill Medical College and The New York Presbyterian Hospital
New York, New York, 10065, United States
NYU Grossman School of Medicine
New York, New York, 10065, United States
Mission Hospital HCA
Asheville, North Carolina, 28801, United States
Aultman Hospital
Canton, Ohio, 44710, United States
TriHealth Inc.
Cincinnati, Ohio, 45202, United States
University of Cincinnati
Cincinnati, Ohio, 45221, United States
Cleveland Clinic
Cleveland, Ohio, 44195, United States
Saint Francis Hospital
Tulsa, Oklahoma, 74136, United States
The Pennsylvania State University and The Milton S. Hershey Medical Center
Hershey, Pennsylvania, 17033, United States
The Trustees of the University of Pennsylvania
Philadelphia, Pennsylvania, 19104, United States
University of Pittsburgh Medical Center (UPMC) Presbyterian Heart and Vascular Institute
Pittsburgh, Pennsylvania, 15213, United States
Rhode Island Hospital
Providence, Rhode Island, 02903, United States
Glanecare, Inc. d/b/a HCA Florida Brandon Hospital
Brentwood, Tennessee, 37027, United States
Texas Cardiac Arrhythmia Research Foundation
Austin, Texas, 78705, United States
Baylor Research Institute
Dallas, Texas, 75204, United States
Heart Rhythm Associates
The Woodlands, Texas, 77380, United States
CHRISTUS Northeast Texas Health System
Tyler, Texas, 75701-2263, United States
The Rector and Visitors of the University of Virginia
Charlottesville, Virginia, 22903, United States
CommonSpirit Health Research Institute
Tacoma, Washington, 98405, United States
The Medical College of Wisconsin
Milwaukee, Wisconsin, 53226, United States
Imeldaziekenhuis
Bonheiden, Antwerpen, 2820, Belgium
AZORG vzw and Hartcentrum Aalst
Aalst, East-Flanders, 9300, Belgium
ASBL CHU Helora - Hôpital de La Louvière - site Jolimont
La Louvière, Hainaut, 7100, Belgium
CHR de la Citadelle
Liège, Liège, 4000, Belgium
AZ Glorieux
Ronse, Oost-Vlaanderen, 9600, Belgium
AZ Sint Jan Brugge AV
Bruges, West-Vlaanderen, 8000, Belgium
AZ Delta VZW
Roeselare, West-Vlaanderen, 8800, Belgium
Universitair Ziekenhuis Brussel
Brussels, 1090, Belgium
University of Calgary
Calgary, Alberta, T2N 1N4, Canada
Vancouver Coastal Health Authority
Vancouver, British Columbia, V5Z 1M9, Canada
St. Boniface Hospital Inc.
Winnipeg, Manitoba, R2H 2A6, Canada
Circulate Cardiac & Vascular Centre (CCVC)
Burlington, Ontario, L7M 1K9, Canada
Cambridge Cardiac Care Inc.
Cambridge, Ontario, N1R 6V6, Canada
Hamilton Health Sciences Corp
Hamilton, Ontario, L8L 2X2, Canada
Research St. Joseph's - Hamilton
Hamilton, Ontario, L8N 4A6, Canada
Waterloo Wellington Cardiovascular Research Institute (WWCRI)
Kitchener, Ontario, N2M 5N6, Canada
Lawson Health Research Institute
London, Ontario, N6A 2R5, Canada
Southlake Regional Health Centre
Newmarket, Ontario, L2Y 2P9, Canada
Partners in Advanced Cardiac Evaluation (PACE)
Newmarket, Ontario, L3Y 2P6, Canada
Ottawa Heart Institute Research Corp
Ottawa, Ontario, K1Y 4W7, Canada
Niagara Health System - Niagara Falls
St. Catharines, Ontario, L2S 0A9, Canada
Niagara Health Systems - St. Catharines
St. Catharines, Ontario, L2S 0A9, Canada
Sunnybrook Health Sciences Center
Toronto, Ontario, M4N 3M5, Canada
Lawrence Park Cardiology
Toronto, Ontario, M4N 3N1, Canada
Unity Health Toronto
Toronto, Ontario, M5B 1W8, Canada
Institut de Cardiologie de Montreal (ICM)
Montreal, Quebec, H1T 1C8, Canada
Centre hospitalier de l'Université de Montréal
Montreal, Quebec, H2X OC1, Canada
Institut universitaire de cardiologie et de pneumologie de Québec-Université Laval
Québec, Quebec, G1V 4G5, Canada
Centre intégré universitaire de santé et de services sociaux de l'Estrie - Centre hospitalier universitaire de Sherbrooke (CIUSSS de l'Estrie - CHUS)
Sherbrooke, Quebec, J1J 3H5, Canada
Prairie Valscular Research Inc. (PVRI)
Regina, Saskatchewan, S4P 0W5, Canada
Saskatchewan Health Authority
Saskatoon, Saskatchewan, S7K 0M7, Canada
Region Hospital Viborg
Viborg, Central Jutland, 8800, Denmark
Aarhus University Hospital (AUH)
Aarhus, Region Midt, 8200, Denmark
Esbjerg & Grindsted Hospital - University Hospital of Southern Denmark
Esbjerg, Region Syddanmark, 6700, Denmark
Rigshospitalet (RH)
Copenhagen, 2100, Denmark
North Denmark Regional Hospital
Hjørring, 9800, Denmark
Odense Universitets Hospital
Odense C, 4500, Denmark
Infirmerie Protestante de Lyon
Caluire-et-Cuire, Auvergne-Rhône-Alpes, 69300, France
CHU Saint Etienne
Saint-Etienne, Auvergne-Rhône-Alpes, 42055, France
Centre Hospitalier Régional Universitaire de Tours
Tours, Centre-Val de Loire, 37044, France
Clinique Pasteur
Toulouse, Occitanie, 31076, France
SCP des Médecins Cardiologues
Toulouse, Occitanie, 31076, France
L'Assistance Publique-Hôpitaux de Marseille
Marseille, Provence-Alpes-Côte d'Azur Region, 13005, France
Hôpital Pitie Salpétrière
Paris, 75013, France
Institut Médico-chirurgical Montsouris
Paris, 75014, France
Hôpital Bichat
Paris, 75018, France
European Georges Pompidou Hospital
Paris, 75908, France
Hospital Prive Jacques Cartier
Massy, Île-de-France Region, 91300, France
Centre Cardiologique due Nord
Saint-Denis, Île-de-France Region, 93200, France
Städtisches Klinikum Karsruhe gGmbH
Karlsruhe, Baden-Wurttemberg, 76133, Germany
Kardiovaskulaeres Zentrum Darmstadt
Darmstadt, Hesse, 64287, Germany
CVC Rhein-Main GmbH
Frankfurt am Main, Hesse, 60389, Germany
MVZ CCB Frankfurt und Main-Taunus GbR
Frankfurt am Main, Hesse, 60431, Germany
Johann Wolfgang Goethe Universität Franfurt - Universitätsklinikum Franfurt
Frankfurt am Main, Hesse, 60590, Germany
Krankenhausbetriebsgesellschaft Bad Oeynhausen mbH
Bad Oeynhausen, North Rhine-Westphalia, 32545, Germany
Westpfalz-Klinikum GmbH
Kaiserslautern, Rhineland-Palatinate, 67665, Germany
Herzzentrum Leipzig GmbH
Leipzig, Saxony, 04289, Germany
Universitätsklinikum Schleswig - Holstein
Lübeck, Schleswig-Holstein, 23538, Germany
Katholisches Krankenhaus "St. Johann Nepomuk"
Erfurt, Thuringia, 99097, Germany
Charité Universitätsmedizin Berlin
Berlin, 10117, Germany
Charité - Universitätsmedizin Berlin
Berlin, 12203, Germany
Asklepios Kliniken Hamburg GmbH
Hamburg, 20099, Germany
Asklepios Kliniken Hamburg GmbH
Hamburg, 20099, Germany
Universitätsklinikum Hamburg-Eppendorf (UKE)
Hamburg, 20246, Germany
Universitätsklinikum Heidelberg
Heidelberg, 69120, Germany
Fondazione Poliambulanza Istituto Ospedaliero
Brescia, 25124, Italy
Stichting Catharina Ziekenhuis
Eindhoven, North Brabant, 5623EJ, Netherlands
American Heart of Poland SA
Ustroń, 43-450, Poland
Hospital Álvaro Cunqueiro
Vigo, Pontevedra, 36312, Spain
University General Hospital Dr. Balmis
Alicante, 03010, Spain
Complejo Asistencial Universitario de León
León, 24071, Spain
Universitario La Luz - Grupo Quirónsalud
Madrid, 28003, Spain
Hospital Clínico Universitario de Valladolid
Valladolid, 47003, Spain
University Hospitals of Leicester NHS Trust
Leicester, Leicestershire, LE1 5WW, United Kingdom
Oxford University Hospitals NHS Foundation Trust
Oxford, Oxfordshire, OX3 9DU, United Kingdom
University Hospitals Coventry and Warwickshire
Coventry, West Midlands, CV2 2DX, United Kingdom
University Hospitals Sussex NHS Trust
Worthing, West Sussex, BN11 2DH, United Kingdom
Liverpool Heart and Chest Hospital NHS Foundation Trust
Liverpool, L14 3PE, United Kingdom
University Hospital Southampton NHS Foundation Trust
Southampton, SO16 6YD, United Kingdom
Related Publications (1)
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.
PMID: 39344366DERIVED
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Jeff Healey
Hamilton Health Sciences Corporation
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- SINGLE
- Who Masked
- OUTCOMES ASSESSOR
- Masking Details
- Events Adjudication Committee is blinded to intervention assignment.
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
July 5, 2023
First Posted
July 27, 2023
Study Start
November 30, 2023
Primary Completion (Estimated)
September 1, 2029
Study Completion (Estimated)
December 1, 2029
Last Updated
March 12, 2026
Record last verified: 2025-09
Data Sharing
- IPD Sharing
- Will not share