Plugs for left atrial appendage occlusion: an overview of available devices

ABSTRACT

Introduction

Approximately one-third of all ischemic strokes and the ensuing health and economic burden can be attributed to the presence of atrial fibrillation (AF). The global prevalence of AF continues to rise, thus making it by far the most common diagnosed cardiac arrhythmia. Percutaneous left atrial appendage (LAA) occlusion or obliteration has been developed to protect from the occurrence of stroke in patients with nonvalvular AF.

Areas covered

We address the characteristics and techniques for implantation as well as some clinical registries and randomized trials of the various catheter-based devices for the occlusion of the LAA that are either currently available or in the clinical evaluation stage.

Expert opinion

Over less than 2 decades, LAA occlusion progressed from being a concept applied in a few specialized centers to a globally recognized procedure implemented in numerous hospitals as part of daily interventional practice. The respective devices are to date safer and easier to deploy than initially. Periprocedural and postprocedural complications will continue to decrease as already evident from prospective randomized trials and registries. Although current indications focus on patients with nonvalvular AF and contraindications for oral anticoagulation, it is all but certain that the future will bring a widening in the spectrum of indications, applicability, and usage of these devices.

KEYWORDS:

• Atrial fibrillation
• interventional cardiology
• left atrial appendage closure
• non-valvular atrial fibrillation
• stroke prevention

Article highlights

• Atrial fibrillation resulting in an ischemic stroke is a major contributor to global health and economic burden.

• Percutaneous LAAO by either device plugging of the LAA neck or external ligation is a reasonable preventative measure and currently advocated by the ESC guidelines in NVAF patients with a contraindication for oral anticoagulation.

• The Watchman device is currently the only FDA-approved device. However, there are more than five devices with CE approval with the ACP and Amulet occluders as market leaders.

• Occluder devices can be either completely implanted in the appendage or positioned according to the pacifier principle with a distal part as an anchor and plug in the appendage while using a proximal disc as a lid on the os of the LAA.

• Over a course of almost 20 years, device structure and material have become less thrombogenic and safer to deploy, with improved ability to conform to various challenging LAA anatomies and providing complete occlusion.

• The currently available devices still suffer in up to 4.5% of the cases of residual severe peri-device leaks, mostly due to a very large LAA ostium with multiple lobes or inability to co-axially deploy the device [67]. However, percutaneous closure of peri-device leaks is feasible and has been described in multiple case series with either implanting a second LAA occluder device or by using an Amplatzer Vascular Plug [68].

• The overall device-related adverse cardiac events have considerably decreased over the last few years from an incidence of >10% to less than 5%.

• NOACs are currently considered the standard of care in patients with AF. A first randomized trial comparing LAAO and NOACs showed equipoise regarding ischemic events and an advantage for LAAO regarding bleeds [38]. Upcoming randomized trials comparing the efficacy and safety of percutaneous LAA occlusion between devices and NOACs, Amulet versus NOACs (CATALYST Trial), and Watchman versus NOAC, are eagerly awaited and will play a major role in further defining the role of LAAO.

Declaration of interest

B Meier and F Nietlispach have received speaker and proctor fees from Abbott. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

One peer reviewer is a consultant to Abbott, Boston Scientific, and Gore. One peer reviewer is a proctor for Abbott. Peer reviewers on this manuscript have no other relevant financial relationships or otherwise to disclose.

Additional information

Funding

This paper was not funded.