AzTrials
AzTrials

Cardiac Surgery With Cardiopulmonary BypassLAAOS IIINCT01561651

Left Atrial Appendage Occlusion Study III

A study testing Left Atrial Appendage Occlusion in people with Cardiac Surgery With Cardiopulmonary Bypass and Atrial Fibrillation, run by Population Health Research Institute at 1 site in Canada.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

Atrial fibrillation (AF) is a common heart rhythm disorder that leads to one-sixth of all strokes. Prevention of strokes in AF is achieved through the use of blood thinners such as coumadin. Read more about this study

Who is it for?
Ages 18 years and older
What is being tested?
Left Atrial Appendage Occlusion
Could I receive a placebo?
No, everyone receives an active treatment
How many people
4,812 participants
Where
1 siteCanada
Study dates
Jul 2012to May 2021
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Greater than 18 years of age
  • Undergoing a clinically indicated cardiac surgical procedure with the use of cardiopulmonary bypass
  • Have a documented history of atrial fibrillation or atrial flutter
  • CHA2DS2-VASc score ≥ 2
  • Have provided informed consent

Who cannot join

  • Patients undergoing off-pump cardiac surgery
  • Patients undergoing any of the following procedures:
  • heart transplant
  • complex congenital heart surgery
  • sole indication for surgery is ventricular assist device insertion
  • previous cardiac surgery requiring opening of the pericardium
  • mechanical valve implant
  • Patients who have had a previous placement of a percutaneous left atrial appendage closure device

Trial locations and contacts

1 site in 1 country.

Canada1 site

  • Hamilton General Hospital

    Hamilton, Ontario, L8L 2X2

Other trials in Canada

About this study

Atrial fibrillation (AF) is a common heart rhythm disorder that leads to one-sixth of all strokes. Prevention of strokes in AF is achieved through the use of blood thinners such as coumadin. Although these blood thinners are effective, they are limited by the risk of serious bleeding, by physician and patient reluctance to use, and by noncompliance and discontinuation. The left atrial appendage is a structure on the upper chamber of the heart that is the most common source of stroke in patients with AF. This structure is easily accessible during open heart surgery for removal, and has been an area of interest for stroke prevention. However, there is currently no strong evidence that removing it works.

The LAAOS III trial will randomly (like the flip of a coin) assign patients with AF undergoing heart surgery for other reasons to have the left atrial appendage removed or not. These patients, other than this small procedure which has been shown to be quite safe, will be treated in the usual manner. The full study of 4700 patients, followed for an average of 4 years, will determine if removing the left atrial appendage can reduce stroke and other complications on top of usual therapy. A positive study will change the way heart surgery is performed on AF patients and results in a large reduction in the number of strokes in a large population. Further, it will promote further research into this approach that could be applied beyond AF patients undergoing heart surgery.

Being tested
Left Atrial Appendage Occlusion
Keywords
cardiac surgery, left atrial appendage, atrial fibrillation, stroke, non-CNS systemic embolism
Medical subject headings
Atrial Fibrillation, Stroke

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Left Atrial Appendage OcclusionOther

    Surgeon will occlude the left atrial appendage using a suture and/or a surgical stapler or a regulatory approved atrial appendage closure during the patient's cardiac surgery procedure.

Study groups in NCT01561651
Study groupRoleWhat they receive
Left Atrial Appendage Occlusion GroupExperimentalSurgeon will close the left atrial appendage using a suture and/or a surgical stapler or a regulatory approved atrial appendage closure device during the patient's cardiac surgery procedure.
Receives: Other: Left Atrial Appendage Occlusion
No Left Atrial Appendage Occlusion GroupNo interventionSurgeon will not close the left atrial appendage during the patient's cardiac surgery procedure. Patient will be treated as per best medical practice for stroke prevention in atrial fibrillation. Treatment will be decided by the patient's primary care physician.

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Stroke or systemic arterial embolism

    First occurrence of ischemic stroke or transient ischemic attack with positive neuroimaging or systemic arterial embolism

    Measured: Common termination point (median follow-up of 4 years)

Secondary outcomes (4)

  1. All cause stroke or transient ischemic attack with positive neuroimaging or systemic arterial embolism

    All cause stroke or transient ischemic attack with positive neuroimaging or systemic arterial embolism

    Measured: Common termination point (median follow-up of 4 years)

  2. Ischemic stroke or transient ischemic attack with positive neuroimaging or systemic arterial embolism or death

    Ischemic stroke* or transient ischemic attack with positive neuroimaging or systemic arterial embolism or death

    Measured: Common termination point (median follow-up of 4 years)

  3. Ischemic stroke or transient ischemic attack with positive neuroimaging or systemic arterial embolism > 30 days after surgery

    Ischemic stroke or transient ischemic attack with positive neuroimaging or systemic arterial embolism > 30 days after surgery

    Measured: Common termination point (median follow-up of 4 years)

  4. Total mortality

    Total mortality

    Measured: Common termination point (median follow-up of 4 years)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted23 Mar 2012 (estimated)
  2. Study startJul 2012
  3. Primary completionApr 2021
  4. Study completionMay 2021

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Prevention
Allocation
Randomised
Intervention model
Parallel groups
Masking
Quadruple blind
Who is masked
Participant, Care provider, Investigator, Outcomes assessor
Enrolment
4,812 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT01561651
Sponsor's protocol ID
LAAOSIII-2012
Acronym
LAAOS III
Status last verified
Jan 2022
First submitted
20 Mar 2012
Last updated
13 Jan 2022
Results posted
No
Data monitoring committee
Yes

Publications

  • Katsanos AH, Whitlock RP, Belley-Cote EP, Brady K, Wang A, Srivastava A, Jacquin G, Weiss V, Volny O, Sramek M, Peeters A, Marto JP, Wrona P, Tsolaki A, Li L, Nucera A, Mikulik R, Perera K, Catanese L, Shoamanesh A, Sharma M. Stroke Mechanism and Severity After Left Atrial Appendage Occlusion: Insights From the LAAOS III Randomized Clinical Trial. JAMA Neurol. 2026 Jan 1;83(1):76-82. doi: 10.1001/jamaneurol.2025.4478.

    PubMed 41247709

  • Kim KS, Belley-Cote EP, Walsh M, Wang A, Balasubramanian K, Treleaven N, Garg AX, Guyatt G, Whitlock RP. Left atrial appendage occlusion study III-Kidney substudy. Am Heart J. 2025 Oct;288:90-100. doi: 10.1016/j.ahj.2025.04.018. Epub 2025 Apr 19.

    PubMed 40258408

  • Krisai P, Belley-Cote EP, McIntyre WF, Wong J, Tsiplova K, Brady K, Joseph P, Johansson I, Johnson L, Xing LY, Colli A, McGuinness S, Punjabi P, Reents W, Rega F, Budera P, Royse AG, Paparella D, Connolly S, Whitlock RP, Healey JS; on behalf of the LAAOS III Investigators. Heart failure after left atrial appendage occlusion: Insights from the LAAOS III randomized trial. Eur J Heart Fail. 2025 Feb;27(2):285-292. doi: 10.1002/ejhf.3536. Epub 2024 Nov 25.

    PubMed 39586754

  • Whitlock RP, Belley-Cote EP, Paparella D, Healey JS, Brady K, Sharma M, Reents W, Budera P, Baddour AJ, Fila P, Devereaux PJ, Bogachev-Prokophiev A, Boening A, Teoh KHT, Tagarakis GI, Slaughter MS, Royse AG, McGuinness S, Alings M, Punjabi PP, Mazer CD, Folkeringa RJ, Colli A, Avezum A, Nakamya J, Balasubramanian K, Vincent J, Voisine P, Lamy A, Yusuf S, Connolly SJ; LAAOS III Investigators. Left Atrial Appendage Occlusion during Cardiac Surgery to Prevent Stroke. N Engl J Med. 2021 Jun 3;384(22):2081-2091. doi: 10.1056/NEJMoa2101897. Epub 2021 May 15.

    PubMed 33999547

Questions about this trial

What is this clinical trial studying?

A study testing Left Atrial Appendage Occlusion in people with Cardiac Surgery With Cardiopulmonary Bypass and Atrial Fibrillation, run by Population Health Research Institute at 1 site in Canada.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 13 Jan 2022. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Stroke or systemic arterial embolism (time frame: Common termination point (median follow-up of 4 years)). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT01561651, which also lists 4 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 13 Jan 2022.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Keep searching with a free account

You’ve used your 3 free searches for this session. Log in or create a free AzTrials account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in