Cardiac Arrest Due to Brugada Syndrome Associated With Influenza Infection: A Case Report and Literature Review.

A 38-year-old Japanese male with no significant medical history but a family history of sudden cardiac death was referred for cardiac arrest. He had a fever (40°C) one day before his visit. His wife reported that he groaned while unconscious, which prompted a referral to the authors' hospital. He was febrile and experienced ventricular fibrillation in the emergency department. After the resolution of ventricular fibrillation, electrocardiography revealed a right bundle branch block with ST-segment elevation in leads V1-3, consistent with a Brugada electrocardiographic pattern; he also tested positive for influenza A infection. Antiarrhythmic and antipyretic agents were administered, and peramivir was initiated; a fatal arrhythmia did not occur. A cardioverter-defibrillator was implanted, and the patient was discharged without complications. Brugada syndrome is a genetic disease that causes fatal cardiac arrhythmias, with fever recognized to induce the Brugada electrocardiographic pattern. The mechanism of the Brugada-type electrocardiographic pattern, right bundle branch block, and ST-segment elevation in the right precordial leads is considered to be the result of an outward shift of ionic currents during early repolarization, causing a marked abbreviation of the action potential in epicardial cells of the right ventricle. Activation and inactivation kinetics for early sodium currents are faster at higher temperatures. To date, there have only been four published reports describing Brugada-like electrocardiographic changes associated with fever related to influenza infection, and this is the first report of cardiac arrest. Since influenza infection can cause high fever and trigger the fetal arrhythmia of Brugada syndrome, it is important to shorten the duration of the fever. Anti-influenza therapy may be considered in patients who have a history of sudden cardiac arrest in the family, as influenza may influence the development of the Brugada ECG pattern in these individuals. The authors also review the literature on Brugada-like electrocardiographic changes induced by influenza infection. Physicians should be aware that Brugada's electrocardiographic pattern and cardiac arrest can be caused by febrile episodes, including those related to influenza infection.