Type 1 Brugada Pattern Triggered by Low-Grade Fever: Implications for Diagnosis and Risk Stratification

Brugada syndrome (BrS) is a rare but potentially life-threatening condition that may lead to sudden cardiac death. Among the causes, dysfunctions of ion channels involved in the cardiac action potential (specifically in SCN5A and SCN10A genes) are particularly significant. Among diagnosed Brugada patients, fever-induced episodes occur in 20-30% of cases. Fever worsens sodium channel dysfunction, as elevated temperature further reduces their conductance. First clinical manifestation of BrS occurs usually during a febrile episode, especially in young people. We performed a multiparametric examination in addition to genetic analysis. We treated a 19-year-old man presenting with subfebrility. During the patient's subfebrile episodes, 12-lead ECG recordings revealed ST-segment elevations in leads V1-V3. Notably, the patient remained asymptomatic. Targeted genetic testing of SCN5A did not reveal any disease-causing variants as an underlying cause of the syndrome, but the temperature-inducing effect was demonstrated. The occurrence of the Brugada type 1 pattern has also been observed at subfebrile episodes, although significantly rarely. This case demonstrates that in susceptible patients, even a relatively mild elevation in body temperature can trigger ion channel dysfunctions. Timely diagnosis and follow-up are important in preserving quality of life and preventing fatal outcomes.