6.1 LAA Occlusion: Is the “Square Peg in a Round Hole” Problem Now Solved?

These proceedings summarize the educational activity of the 17th Biennial Meeting of the International Andreas Gruentzig Society held January 30 to February 2, 2024 in Chiang Rai, Thailand.

Faculty Disclosures     Vendor Acknowledgments

2024 IAGS Summary Document

Statement of the problem or issue

Left atrial appendage occlusion (LAAO) provides effective thromboembolic risk reduction with less bleeding in patients with atrial fibrillation and is non-inferior to oral anticoagulants. There is ongoing data collection in more contemporary trials, but previous trials have proven this premise. Clinical experience is largely based on 2 current devices, the Watchman and the Amulet.

The questions or issues at hand are shown in Table 1.

Table 1. Current Issues with LAAO.

DRT = device-related thrombus; LAA = left atrial appendage; OAC = oral anticoagulants.

Gaps in current knowledge

I have grouped these gap areas into three major categories: (1) incomplete occlusion; (2) antithrombotics and device-related thrombosis (DRT); and (3) efficacy and best practices, as shown in Table 2.

Table 2. Gaps in Knowledge for LAAO.

DRT = device-related thrombosis; LAA = left atrial appendage; OAC = oral anticoagulants.

Possible solutions and future directions

I have listed my ideas in Table 3. The quality of the devices and the procedures themselves are being called into question. An ideal LAA occlusion device should safely eliminate any flow into or out of the LAA and not implant any thrombogenic foreign material. This is not consistently achieved with current generation technology. Furthermore, we don’t have very good long-term follow-up data on patients with and without optimal implants, especially those without. Lacking these data, providers struggle with guiding optimal thrombotic risk reduction.

Given that the LAAO advantage is largely due to reduced bleeding risk compared to OAC, additional methods for decreasing or eliminating the need for any post-procedure antithrombotics are wanting. Without complete elimination of post-procedure antithrombotics, LAAO therapy does not provide superior options for patients with both prohibitive bleeding risk and simultaneously elevated atrial fibrillation-related thromboembolic risk. Evidence-based best practices are lacking at present, but if they could be developed they could improve the therapeutic and safety profiles and expand access. There is a need for LAAO across many demographic groups. However, availability of the therapy is not equitable, nor will it be without the concerted efforts of stakeholders.

Table 3. Future directions for LAAO.

LAAO = left atrial appendage occlusion.

References

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2. Holmes DR Jr, Schwartz RS, Latus GG, et al. A History of Left Atrial Appendage Occlusion. Interv Cardiol Clin. 2018;7(2):143-150. PMID: 29526283 DOI: 10.1016/j.iccl.2017.12.005
3. Aberg H. Atrial fibrillation: I. A study of atrial thrombosis and systemic embolism in a necropsy material. Acta Med Scand. 1969;185(5):373-379. PMID: 5808636
4. Reddy VY, Sievert H, Halperin J, et al. Percutaneous left atrial appendage closure vs warfarin for atrial fibrillation: a randomized clinical trial. Jama. 2014;312(19):1988-1998. doi: 10.1001/jama.2014.15192
5. Turagam MK, Reddy VY, and Dukkipati SR, EWOLUTION of Watchman left atrial appendage closure to patients with contraindication to oral anticoagulation. Circ Arrhythm Electrophysiol, 2019;12(4):e007257. doi: 10.1161/CIRCEP.119.007257
6. Alkhouli M, Ellis C, Daniels M. et al. Left atrial appendage occlusion: current advances and remaining challenges. JACC Advance. 2022, Dec, vol 1, no. 5.
7. Saw J, et al. SCAI/HRS expert consensus statement on transcatheter left atrial appendage closure. Heart Rhythm. 2023;20(5), May.
8. Sommer R, Kim J, Szerlip M, et al. Conformal left atrial appendage seal device for left atrial appendage closure: first clinical use. JACC Cardiac Interv. 2021;14(21):2368–2374.
9. Kar S. https://www.vumedi.com/video/a-revolutionary-approach-to-left-atrial-appendage-closure-laminar-early-clinical-experience/