The Fourth Left Atrial Appendage Occlusion Study (LAAOS-4)

Hamilton Health Sciences (HHS)

Status: Enrolling

Conditions: Atrial Fibrillation; Systemic Embolism; Stroke, Ischemic

Treatments: Device: WATCHMAN device

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT05963698

LAAOS-4

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 4,000 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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4,000 participants in 2 patient groups

WATCHMAN device

Experimental group

Description:

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

Treatment:

Device: WATCHMAN device

Standard Care

No Intervention group

Description:

Participants will receive local, standard medical care