How to Assess the Impact of Left Atrial Appendage Emptying Velocity on the Recurrence of Atrial Fibrillation After Catheter Ablation

To the Editor:

Kim et al effectively illustrated that a diminished left atrial appendage emptying velocity (LAAV) stands as an autonomous predictor for the resurgence of atrial fibrillation (AF) post totally thoracoscopic ablation (TTA).¹

The reduction in LAAV during AF due to the absence of atrial contraction is self-evident. Assessing LAAV during sinus rhythm is imperative.² In the authors’ investigation, it appears that all patients exhibiting lower LAAV had persistent AF.¹ Integrating this particular AF subtype into the multivariable analysis is advisable, considering its substantial impact on the recurrence rate. Enhancing LAAV levels can be accomplished through isoproterenol loading.³ Performing such a test on individuals with diminished LAAV could yield further valuable insights into identifying high-risk refractory patients.

In the authors’ institute,¹ a routine post-procedural electrophysiologic study followed by cavo-tricuspid isthmus ablation was previously conducted. Presently, an electrophysiologic study, along with touch-up ablation, is exclusively administered to patients exhibiting atrial tachyarrhythmia refractory to epicardial ablation. This procedural variance might have influenced the recurrence rate. It is noteworthy that the presence of cavo-tricuspid isthmus ablation is anticipated to significantly impact the recurrence of atrial flutter.

Patients lacking left atrial appendage removal were excluded from their investigation.¹ Some individuals with preserved LAAV might have experienced AF relapse, suggesting the potential involvement of the left atrial appendage as an AF trigger.⁴

Disclosure

None.

• Naoya Kataoka, MD, PhD
• Teruhiko Imamura, MD, PhD
• Second Department of Internal Medicine, University of Toyama, Toyama, Japan

References

• 1.   Kim J, Bak M, Park SJ, Jeong DS, Chung S, Kim D, et al. Clinical implication of left atrial appendage emptying velocity in thoracoscopic ablation of atrial fibrillation. Circ J 2023; 87: 1742–1749.
• 2.   Fukuhara E, Mine T, Kishima H, Ishihara M. Predictors for reduced flow velocity in left atrial appendage during sinus rhythm in patients with atrial fibrillation. Heart Vessels 2021; 36: 393–400.
• 3.   Goyal SK, Hyder S, Liu S, Vannan MA. Isoproterenol-assisted differentiation between sludge and organized thrombus to guide left atrial appendage occlusion. JACC Clin Electrophysiol 2023; 9: 111–116.
• 4.   Di Biase L, Burkhardt JD, Mohanty P, Mohanty S, Sanchez JE, Trivedi C, et al. Left atrial appendage isolation in patients with longstanding persistent AF undergoing catheter ablation: BELIEF trial. J Am Coll Cardiol 2016; 68: 1929–1940.