What is Left Atrial Appendage Occlusion (LAAO)?

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Last updated: April 16, 2025View editorial policy

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From the Guidelines

LAAO, or Left Atrial Appendage Occlusion, is a procedure used to reduce stroke risk in patients with atrial fibrillation who cannot take blood thinners, and its effectiveness in stroke prevention is supported by recent guidelines and studies, such as the 2024 ESC guidelines 1. The left atrial appendage is a small pouch in the heart where blood clots commonly form during atrial fibrillation. During the LAAO procedure, a device is implanted to seal off this appendage, preventing clots from escaping and causing strokes. The procedure is typically performed under general anesthesia and involves inserting a catheter through a vein in the leg up to the heart, where the occlusion device is deployed. After LAAO, patients usually take blood thinners for a short period until the device is fully incorporated into the heart tissue, after which many can discontinue them. Some key points to consider about LAAO include:

  • The LAAOS III trial showed that surgical occlusion or exclusion of the left atrial appendage can contribute to stroke prevention in patients with AF undergoing cardiac surgery, with a significant reduction in ischemic stroke or systemic embolism 1.
  • The procedure is particularly beneficial for patients with high bleeding risks, medication compliance issues, or those who experience adverse effects from anticoagulants.
  • The effectiveness of LAAO in stroke prevention is comparable to warfarin therapy in appropriate candidates, as shown in studies such as the PROTECT AF and PREVAIL trials 1.
  • Recent guidelines, such as the 2024 ESC guidelines, recommend considering percutaneous LAA occlusion in patients with AF and contraindications for long-term anticoagulant treatment to prevent ischemic stroke and thromboembolism 1.
  • The choice of antithrombotic therapy after LAAO is still a topic of debate, with some studies suggesting the use of direct oral anticoagulants or antiplatelet therapy instead of warfarin 1.

From the Research

Definition of LAAO

  • Left Atrial Appendage Occlusion (LAAO) is a method of reducing the risk of stroke in patients with atrial fibrillation by occluding the left atrial appendage, where thrombi often form 2.
  • LAAO is considered an effective alternative to oral anticoagulation for stroke prevention in patients with non-valvular atrial fibrillation 3, 4.

Purpose of LAAO

  • The primary purpose of LAAO is to prevent ischemic stroke and systemic embolism in patients with atrial fibrillation, particularly those at high risk of thromboembolism or bleeding 2, 5.
  • LAAO is also considered for patients with contraindications to pharmacologic anticoagulation or those who cannot tolerate long-term oral anticoagulation 3, 6.

Types of LAAO

  • There are two main types of LAAO: percutaneous (transcatheter) and surgical 6.
  • Percutaneous LAAO involves the use of devices such as the Watchman, which is implanted through a catheter to occlude the left atrial appendage 4.
  • Surgical LAAO is typically performed during cardiac surgery and involves the removal or occlusion of the left atrial appendage 2.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

A real-world multicenter study on left atrial appendage occlusion: The Italian multi-device experience.

International journal of cardiology. Heart & vasculature, 2024

Research

Left Atrial Appendage Occlusion: A Narrative Review.

Journal of cardiothoracic and vascular anesthesia, 2019

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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