Recruiting

Left Atrial Appendage OcclusionThe Fourth Left Atrial Appendage Occlusion Study

Sponsor:

Hamilton Health Sciences Corporation

Code:

NCT05963698

Conditions

Atrial Fibrillation

Stroke, Ischemic

Systemic Embolism

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

WATCHMAN device

Study Details

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.

Conditions

Atrial Fibrillation

Stroke, Ischemic

Systemic Embolism

Study ID

NCT05963698

Start date

Nov 30, 2023

Status verified date

Jun, 2026

Completion date

Dec 1, 2029

Anticipated

Primary completion date

Sep 1, 2029

Anticipated

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

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

Study Design

Enrollment

4000 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: WATCHMAN device

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

no intervention: Standard Care

Participants will receive local, standard medical care

Interventions

WATCHMAN device

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

Primary outcome measure

Ischemic stroke or systemic embolism [ Time Frame: 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). ]

Central Contacts and Locations

Central contacts

Program Director

905-521-2100 LAAOS-4@phri.ca

Locations

Arrhythmia Research Group

Recruiting

Jonesboro, Arkansas, United States, 72401

Principal Investigator:

Devi Nair, MD

Memorial Health Services

Recruiting

Fountain Valley, California, United States, 92708

Principal Investigator:

Nikhil Warrier, MD

Loma Linda University Health

Recruiting

Loma Linda, California, United States, 92354

Principal Investigator:

Rahul Bhardwaj, MD

Southern California Permanente Medical Group

Recruiting

Pasadena, California, United States, 91101

Principal Investigator:

Bahram Khadivi, MD

Sutter Valley Hospitals dba Sutter Institute for Medical Research

Recruiting

Sacramento, California, United States, 95816

Principal Investigator:

David Roberts, MD

JFK Medical Center Limited Partnership d/b/a HCA Florida JFK Hospital

Recruiting

Atlantis, Florida, United States, 33462

Principal Investigator:

Marcelo Jimenez, MD

St. Vincent's Health System

Recruiting

Jacksonville, Florida, United States, 32204

Principal Investigator:

Saumil Oza, MD

Largo Medical Center, Inc. d/b/a HCA Florida Largo Medical Center

Recruiting

Largo, Florida, United States, 33770

Principal Investigator:

Jesse Klein, MD

HCA Florida Ocala Hospital

Recruiting

Ocala, Florida, United States, 34471

Principal Investigator:

Gregory Von Mering, MD

The University of South Florida

Recruiting

Tampa, Florida, United States, 33620

Principal Investigator:

Bibhu Mohanty, MD

Emory University

Recruiting

Atlanta, Georgia, United States, 30322

Principal Investigator:

David De Lurgio, MD

St Luke's Regional Medical Center, Ltd

Recruiting

Boise, Idaho, United States, 83712

Principal Investigator:

Marcos Daccarett, MD

Kootenai Health Inc.

Recruiting

Coeur d'Alene, Idaho, United States, 83814

Principal Investigator:

Michele Murphy-Cook, MD

Northwestern University

Recruiting

Evanston, Illinois, United States, 60208

Principal Investigator:

Albert Lin, MD

Cardiovascular Medicine, PLLC and Unity Point Trinity Rock Island

Recruiting

Rock Island, Illinois, United States, 61201

Principal Investigator:

Mark Shen, MD

Community Health Network Inc.

Recruiting

Indianapolis, Indiana, United States, 46256

Principal Investigator:

Krishna Malineni, MD

MercyOne Iowa Heart Center

Recruiting

West Des Moines, Iowa, United States, 50266

Principal Investigator:

Pitayadet Jumrussirikul, MD

University of Kansas Medical Center Research Institute, Inc.

Recruiting

Kansas City, Kansas, United States, 66160

Principal Investigator:

Madhu Reddy, MD

Babtist Health Lexington

Recruiting

Lexington, Kentucky, United States, 40503

Principal Investigator:

Gery Tomassoni, MD

Ochsner Clinic Foundation

Recruiting

New Orleans, Louisiana, United States, 70121

Principal Investigator:

Richard Zweifler, MD

University of Maryland Baltimore

Recruiting

Baltimore, Maryland, United States, 21201

Principal Investigator:

Seemant Chaturvedi, MD

Lahey Clinic Inc.

Recruiting

Burlington, Massachusetts, United States, 01805

Principal Investigator:

Bruce Hook, MD

University of Michigan

Recruiting

Ann Arbor, Michigan, United States, 48109

Principal Investigator:

Hakan Oral, MD

Henry Ford Health System

Recruiting

Detroit, Michigan, United States, 48202

Principal Investigator:

Waddah Maskoun, MD

Henry Ford Health System

Recruiting

Detroit, Michigan, United States, 48202

Principal Investigator:

Amir Kaki, MD

Mayo Clinic

Recruiting

Rochester, Minnesota, United States, 55905

Principal Investigator:

Eugene L. Scharf, MD

Hackensack University Medical Center

Recruiting

Hackensack, New Jersey, United States, 07601

Principal Investigator:

Taya Glotzer, MD

Presbyterian Healthcare Services d.b.a. Presbyterian Heart Group

Recruiting

Albuquerque, New Mexico, United States, 87106

Principal Investigator:

Sharif Halim, MD

The Feinstein Institutes for Medical Research

Recruiting

Manhasset, New York, United States, 11030

Principal Investigator:

Jeffrey Katz, MD

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

Recruiting

New York, New York, United States, 10065

Principal Investigator:

Christopher Liu, MD

Mission Hospital HCA

Recruiting

Asheville, North Carolina, United States, 28801

Principal Investigator:

John Rhyner, MD

Aultman Hospital

Recruiting

Canton, Ohio, United States, 44710

Principal Investigator:

Firas Hamdan, MD

TriHealth Inc.

Recruiting

Cincinnati, Ohio, United States, 45202

Principal Investigator:

Gaurang Gandhi, MD

University of Cincinnati

Recruiting

Cincinnati, Ohio, United States, 45221

Principal Investigator:

Srinivas Rajsheker, MD

Cleveland Clinic

Recruiting

Cleveland, Ohio, United States, 44195

Principal Investigator:

Oussama Wazni, MD

Saint Francis Hospital

Recruiting

Tulsa, Oklahoma, United States, 74136

Principal Investigator:

Tom Hu, MD

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

Recruiting

Hershey, Pennsylvania, United States, 17033

Principal Investigator:

Soraya Samii, MD

The Trustees of the University of Pennsylvania

Recruiting

Philadelphia, Pennsylvania, United States, 19104

Principal Investigator:

Steven Messe, MD

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

Recruiting

Pittsburgh, Pennsylvania, United States, 15213

Principal Investigator:

Sandeep Jain, MD

Rhode Island Hospital

Recruiting

Providence, Rhode Island, United States, 02903

Principal Investigator:

Ana-Lucia Garcia-Guarniz, MD

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

Recruiting

Brentwood, Tennessee, United States, 37027

Principal Investigator:

Umesh Gowda, MD

The University of Tennessee

Recruiting

Memphis, Tennessee, United States, 38163

Principal Investigator:

Balaji Krishnaiah, MD

Baylor Research Institute

Recruiting

Dallas, Texas, United States, 75204

Principal Investigator:

Praveen Rao, MD

CHRISTUS Northeast Texas Health System

Recruiting

Tyler, Texas, United States, 75701-2263

Principal Investigator:

Stanislav Weiner, MD

The Rector and Visitors of the University of Virginia

Recruiting

Charlottesville, Virginia, United States, 22903

Principal Investigator:

Rohit Malhotra, MD

CommonSpirit Health Research Institute

Recruiting

Tacoma, Washington, United States, 98405

Principal Investigator:

Nasir Shariff, MD

The Medical College of Wisconsin

Recruiting

Milwaukee, Wisconsin, United States, 53226

Principal Investigator:

James Oujiri, MD

University of Calgary

Recruiting

Calgary, Alberta, Canada, T2N 1N4

Principal Investigator:

Stephen Wilton, MD

Vancouver Coastal Health Authority

Recruiting

Vancouver, British Columbia, Canada, V5Z 1M9

Principal Investigator:

Jason Andrade, MD

St. Boniface Hospital Inc.

Recruiting

Winnipeg, Manitoba, Canada, R2H 2A6

Principal Investigator:

Malek Kass, MD

Circulate Cardiac & Vascular Centre (CCVC)

Recruiting

Burlington, Ontario, Canada, L7M 1K9

Principal Investigator:

Hisham Dokainish, MD

Cambridge Cardiac Care Inc.

Recruiting

Cambridge, Ontario, Canada, N1R 6V6

Principal Investigator:

A. Shekhar Pandey, MD

Hamilton Health Sciences Corp

Recruiting

Hamilton, Ontario, Canada, L8L 2X2

Principal Investigator:

Guy Amit, MD

Research St. Joseph's - Hamilton

Recruiting

Hamilton, Ontario, Canada, L8N 4A6

Principal Investigator:

Vikas Tandon, MD

Waterloo Wellington Cardiovascular Research Institute (WWCRI)

Recruiting

Kitchener, Ontario, Canada, N2M 5N6

Principal Investigator:

Umjeet Jolly, MD

Lawson Health Research Institute

Recruiting

London, Ontario, Canada, N6A 2R5

Principal Investigator:

Allan Skanes, MD

Southlake Regional Health Centre

Recruiting

Newmarket, Ontario, Canada, L2Y 2P9

Principal Investigator:

Mouhannad Sadek, MD

Partners in Advanced Cardiac Evaluation (PACE)

Recruiting

Newmarket, Ontario, Canada, L3Y 2P6

Principal Investigator:

Yaariv Khaykin, MD

Ottawa Heart Institute Research Corp

Recruiting

Ottawa, Ontario, Canada, K1Y 4W7

Principal Investigator:

Omar Abdel-Razek, MD

Niagara Health System - Niagara Falls

Recruiting

St. Catharines, Ontario, Canada, L2S 0A9

Principal Investigator:

Danielle de Sa Boasquevisque, MD

Niagara Health Systems - St. Catharines

Recruiting

St. Catharines, Ontario, Canada, L2S 0A9

Principal Investigator:

Nigel Tan, MD

Sunnybrook Health Sciences Center

Recruiting

Toronto, Ontario, Canada, M4N 3M5

Principal Investigator:

Sheldon Singh, MD

Lawrence Park Cardiology

Recruiting

Toronto, Ontario, Canada, M4N 3N1

Principal Investigator:

Eugene Crystal, MD

Unity Health Toronto

Recruiting

Toronto, Ontario, Canada, M5B 1W8

Principal Investigator:

Neil Fam, MD

University Health Network

Recruiting

Toronto, Ontario, Canada, M5G 2C4

Principal Investigator:

Eric Horlick, MD

Institut de Cardiologie de Montreal (ICM)

Recruiting

Montreal, Quebec, Canada, H1T 1C8

Principal Investigator:

Reda Ibrahim, MD

Centre hospitalier de l'Université de Montréal

Recruiting

Montreal, Quebec, Canada, H2X OC1

Principal Investigator:

Jean-Marc Raymond, MD

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

Recruiting

Québec, Quebec, Canada, G1V 4G5

Principal Investigator:

Jean Champagne, MD

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

Recruiting

Sherbrooke, Quebec, Canada, J1J 3H5

Principal Investigator:

Charles Dussault, MD

Prairie Valscular Research Inc. (PVRI)

Recruiting

Regina, Saskatchewan, Canada, S4P 0W5

Principal Investigator:

Payam Dehghani, MD

Saskatchewan Health Authority

Recruiting

Saskatoon, Saskatchewan, Canada, S7K 0M7

Principal Investigator:

Stephan Wardell, MD

More Information

Sponsor

Hamilton Health Sciences Corporation

Last update posted

Jun 8, 2026

Last verified

Jun, 2026

Keywords

WATCHMAN
Left Atrial Appendage (LAA)
LAA Device
Left Atrial Appendage Occlusion

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-08. This information was provided to ClinicalTrials.gov by Hamilton Health Sciences Corporation on 2026-06-08.