An Atypical Familial Presentation of Brugada Syndrome: Can this be Considered as an Overlap Syndrome of the Long QT and Brugada Syndromes?

Abstract

Long QT syndrome (LQTS) and Brugada syndrome (BrS) are well-known congenital channelopathies that can cause sudden cardiac death (SCD). Although various genetic mutations are associated with LQTS and BrS, an electrocardiogram (ECG) is typically preferred to genetic analysis as a diagnostic tool in clinical practice. However, care must be taken when using ECG in the diagnosis of LQTS or BrS, because the characteristic ECG changes of these syndromes are not observed consistently. The ECG pattern can be altered by various factors such as an aborted SCD, the autonomic nervous system, medication, circadian rhythms, and electrolyte imbalance. Here, we report our experience with a family in which the proband displayed an ECG pattern that initially suggested the presence of LQTS but was ultimately diagnosed as BrS, based on the findings of serial ECG follow-up, a drug provocation test, and genetic analysis. CASE REPORTS