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Published on: December 22, 2020
Citrus fruits induced swallow syncope with atrioventricular block or sinus arrest
Yoshiaki Yamaguchi1, Koichi Mizumaki2, Tamotsu Sakamoto1
1The Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama, Toyama 930-0194, Japan.
Abstract:
Swallow syncope is a relatively rare syndrome and caused by various foods and drinks. A 76-year-old man was admitted with frequent syncope while eating. Holter electrocardiogram revealed frequent occurrence of atrioventricular block during meals. Both atrioventricular block and sinus arrest were induced by only eating citrus fruits, citrus jelly, and acidic foods but not by other drinks and foods. These arrhythmias were suppressed after administration of atropine. No further episodes of syncope recurred after the implantation of a DDD pacemaker. This case indicated that acidic stimulation of citrus induced a vasovagal reflex via esophageal nociceptors leading to syncope.
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