JACC: CASE REPORTS

VOL. 29, 2024

ª 2024 THE AUTHORS. PUBLISHED BY ELSEVIER ON BEHALF OF THE AMERICANCOLLEGE OF CARDIOLOGY FOUNDATION. THIS IS AN OPEN ACCESS ARTICLE UNDER
THE CC BY LICENSE (http://creativecommons.org/licenses/by/4.0/).

RHYTHM DISORDERS AND ELECTROPHYSIOLOGYIMAGING VIGNETTE: CLINICAL VIGNETTE

An Uncommon Cause of Syncopeand Left Atrial Appendage Thrombus
Speech-Induced Atrial Tachycardia
Shiro Miura, MD, PHD, Wataru Nagahori, MD, Hirofumi Mitsuyama, MD, PHD, Takehiro Yamashita, MD, PHDABSTRACTAn 83-year-old, previously healthy woman experienced frequent episodes of syncope following conversations.
Speech-induced atrial tachycardia complicated by left atrial appendage thrombus was diagnosed as a potential etiology.
She was successfully treated via catheter ablation. This is the ﬁrst case report suggesting an association between
arrhythmia, syncope, and atrial thrombus formation. (JACC Case Rep 2024;29:102470) © 2024 The Authors.
Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article
under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

An 83-year-old woman was referred for frequent episodes of syncope following conversations over thepast 3 months. Syncope occurred during standing and sitting, but not while lying down. Her past medical history was unremarkable except for well-controlled hypertension. Vital signs revealed a heart

rate of 81 beats/min, a blood pressure of 142/76 mm Hg, a respiratory rate of 14 breaths/min, a body temperature of 36.5  C, and an oxygen saturation of 98%. The physical examination was unremarkable. The 12-leadelectrocardiogram (Figure 1A) and echocardiogram on admission were normal. A brain magnetic resonance imaging revealed no evidence indicating a transitory ischemic attack, silent stroke, or a possible genesis of syncope. According to 24-hour Holter monitoring, transient supraventricular tachycardia ($3 beats) wasfrequently recorded in 14% of the total recording time, with the longest episode lasting 25 seconds. With a
14-day cardiac event recorder, atrial ﬁbrillation (AF) was not detected. In-hospital cardiac monitoring revealed
that atrial tachycardia (AT) (Figure 1B) triggered by premature atrial complexes could be reproducibly induced
when she started speaking, immediately terminating when she stopped speaking. Deep breaths, deglutition, orcoughing could not provoke the AT. A simultaneous continuous 12-lead electrocardiogram and invasive bloodpressure monitoring in our catheterization laboratory (Figure 1C, Video 1) revealed that the rapid AT was reproducibly induced by her speech and caused a substantial drop in blood pressure along with dizziness. Theseﬁndings led to the diagnosis of speech-induced AT. 1 The patient was initially treated with 2.5 mg of bisoprolol
daily for 4 weeks, which failed to alleviate her symptoms fully. Therefore, an electrophysiological study withsubsequent catheter ablation was scheduled. Contrast cardiac computed tomography (Figure 1E) identiﬁed aleft atrial appendage thrombus, which was completely resolved after daily administration of edoxaban
30 mg for 3 months (Figure 1F). Cardiac magnetic resonance imaging and Technetium-99m pyrophosphate single photon emission computed tomography showed no remarkable ﬁndings suggesting underling cardiomyopathies such as cardiac amyloidosis. An electrophysiological study using the EnSite X EP System (Abbott)(Supplemental Figure 1A) revealed that the earliest focal activation site of the AT was on the septal side of

From the Department of Cardiology, Sapporo Kojinkai Memorial Hospital, Sapporo, Japan.
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’
institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information,
visit the Author Center.
Manuscript received March 14, 2024; revised manuscript received June 14, 2024, accepted June 25, 2024.

ISSN 2666-0849

https://doi.org/10.1016/j.jaccas.2024.102470

2Miura et al

JACC: CASE REPORTS, VOL. 29, 2024

Speech-Induced Atrial Tachycardia

ABBREVIATIONS
AND ACRONYMS
AF = atrial ﬁbrillation
AT = atrial tachycardia

AUGUST 21, 2024:102470

the right atrium, which was successfully ablated (Supplemental Figure 1B). Before discharge, repeatedsimultaneous continuous 12-lead electrocardiogram and blood pressure monitoring conﬁrmed theabsence of speech-induced arrhythmia (Figure 1D, Video 2). At the 3-month visit, she was asymptomatic with no recurrence of AT and no other atrial arrhythmia recorded.

DISCUSSION
Speech-induced AT is an uncommon, debilitating arrhythmia that can cause palpitations and presyncope
during conversations.1 Reliable correlation between each episode of speech and subsequent onset of a rapid,
narrow complex tachycardia is highly diagnostic. The unique phenomenon can be functionally related to theautonomic nervous system rather than anatomical abnormalities, although the underlying mechanisms remain

F I G U R E 1 Multimodality Imaging Findings

Twelve-lead electrocardiograms show normal sinus rhythm at initial presentation (A) and sustained atrial tachycardia (AT) during conversation (B) with 1:1 conduction at
173 beats/min. Blue arrows indicate positive P waves. Simultaneous continuous 12-lead electrocardiogram and invasive blood pressure monitoring at initialpresentation (C) demonstrate an acute drop in blood pressure triggered (white arrows) by rapid AT during conversation from 208/89 mm Hg (heart rate, 83 beats/min)to 73/61 mm Hg (171 beats/min) in the supine position. By contrast, simultaneous monitoring after catheter ablation (D) shows no change in blood pressure and heart
rhythm during conversation. Contrast cardiac computed tomography at initial presentation (E) shows a thrombus in the left atrial appendage (LAA) (red arrowhead),whereas one after oral anticoagulant therapy (F) shows complete thrombus resolution (blue arrowhead).

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Speech-Induced Atrial Tachycardia

AUGUST 21, 2024:102470

poorly elucidated.2 We believe her syncope, an extremely rare complication of the entity, was most likely
linked to vasomotor factors by autonomically mediated focal AT.3 We could conﬁrm relationships between
symptoms, blood pressure, and AT using a novel approach, that is, simultaneous rhythm and blood pressure
monitoring. Pharmacologic therapy, predominantly using beta-blockers, is a safe and accessible option for the
initial management of symptoms. Catheter ablation is a widely used, highly effective, and preferred long-term
therapy for focal AT when pharmacologic therapy fails.1,2 We identiﬁed the septal side of the right atrium, close
to anterior right ganglionated plexuses, 2 as the arrhythmogenic origin and successfully ablated it without
reported recurrence. Based on the Holter monitoring analysis, we speculated that the high arrhythmia burden
had impaired left atrial appendage function, thereby causing thrombus formation. Nevertheless, the possibilityof an undetected AF cannot be ignored, although AF was not recorded after catheter ablation.

FUNDING SUPPORT AND AUTHOR DISCLOSURESThe authors have reported that they have no relationships relevant to the contents of this paper to disclose.

ADDRESS FOR CORRESPONDENCE: Dr Shiro Miura, Department of Cardiology, Sapporo Kojinkai MemorialHospital, 2-1-16-1 Miyanosawa, Nishi-ku, Sapporo 063-0052, Japan. E-mail: s.miura@sap-kojk.jp. X handle:@MiuraShiro.

REFERENCES
1. Hurtado GMP, Clarke JD, Zimerman A, Maher T,Tavares L, d’Avila A. Speech-induced atrial tachycardia: a narrative review of putative mechanisms
implicating the autonomic nervous system. HeartRhythm. 2023;4:574–580.
2. Ueno A, Morita N, Kobayashi Y. Speechtriggered atrial tachycardia originating fromthe superior vena cava. Europace. 2014;16:1303.
3. Leitch JW, Klein GJ, Yee R, Leather RA,Kim YH. Syncope associated with supraventricular tachycardia. An expression of tachycardia
rate or vasomotor response? Circulation.
1992;85:1064–1071.

KEY WORDS atrial arrhythmia, computedtomography, left atrial thrombosis, syncope
A PP END IX For a supplemental ﬁgure andvideos, please see the online version of thispaper.