PhD Scientific Days 2025

Poster Session II. - U: Cardiovascular Medicine and Research

Comparative Analysis of Therapeutic Strategies in Atrial Fibrillation Patients with Left Atrial Appendage Thrombus Despite Optimal NOAC Therapy

Name of the presenter

Arnóth Bence

Institute/workplace of the presenter

Semmelweis University Heart and Vascular Centre

Authors

Bence Arnóth MD¹, Ferenc Komlósi MD¹, Imre Szakál MD¹, Patrik Tóth MD¹, Henriette Mészáros MD¹, Helga Sánta¹, Gyula Bohus¹, Péter Vámosi MD¹, Elektra Bartha MD¹, Márton Horváth MD¹, Melinda Boussoussou MD, PhD¹, Nándor Szegedi MD, PhD¹, Zoltán Salló MD¹, István Osztheimer MD, PhD¹, Péter Perge MD, PhD¹, Gábor Széplaki MD, PhD², László Gellér MD, PhD, DSc¹, Béla Merkely MD, PhD, DSc¹, Klaudia Vivien Nagy MD, PhD¹

1: Semmelweis University Heart and Vascular Centre
2: Mater Private Hospital, Dublin, Ireland

Text of the abstract

Abstract

Introduction: Left atrial appendage (LAA) thrombus is the primary cause of stroke and systemic embolism in atrial
fibrillation (AF). Non-vitamin-K oral anticoagulants (NOACs) effectively reduce LAA thrombus prevalence and stroke risk.
However, the optimal treatment of a NOAC-resistant thrombus remains unclear.
Aims: We aimed to evaluate therapeutic strategies
for resolving LAA thrombus in patients on optimal NOAC therapy.

Methods: We retrospectively analyzed patients scheduled for cardioversion or catheter ablation of AF between 2014 and
2023 with LAA thrombus on transesophageal echocardiography (TEE) despite being on optimal NOAC therapy. We assessed how the applied management strategy affected thrombus resolution.

Results: Among the analyzed 120 patients, a change to a different NOAC occurred in 41% of cases, a transition to a VKA in
30%, and the supplementation with antiplatelet therapy in 11%. In contrast, 18% of the patients received unchanged therapy.
Follow-up imaging at 65 [44 – 95] days showed successful thrombus resolution in 92 (77%) of cases, predicted by a lower
CHA2DS2-VASc score (p = 0.01). Any modification of antithrombotic therapy was an independent predictor of thrombus
resolution (OR 5.28 [1.55–18], p = 0.01). Of the four strategies, there was a trend toward better thrombus resolution with
switching to a VKA (OR 3.23 [1.03–10.1], p = 0.04).

Conclusion: Resolution of LAA thrombus in patients already on adequate NOAC treatment may require a revision of the
anticoagulation strategy. In addition, transitioning from NOAC to VKA might be considered.

Funding: Project no. RRF-2.3.1-21-2022-00003 has been implemented
with the support provided by the European Union.