[SCN5A mutation in patients with Brugada electrocardiographic pattern induced by fever].

OBJECTIVE

To explore the relationship between SCN5A, SCN1b, SCN3b and GPD1L genotypes and the risk of malignant arrhythmia in patients with Brugada electrocardiographic pattern induced by fever.

METHODS

The clinical data and peripheral blood of patients with Brugada electrocardiographic pattern induced by fever were collected. Patients with depolarization abnormality associated with hypertension, coronary heart disease, drugs and other factors were excluded. The direct DNA sequencing was used to screen the mutation of candidate gene SCN5A, SCN1b, SCN3b and GPD1L. If gene variation was found, mutation or polymorphism was then determined by comparison with 200 control individuals. The relationship between genotype and phenotype as well as the risk of malignant arrhythmia were analyzed.

RESULTS

Five eligible patients with fever-induced Brugada ECG pattern were included in this study. TypeI Brugada ECG was presented in all five patients in fibrile state and disappeared in normothermia. No sudden cardiac death (SCD) occurred and no ventricular arrhythmia was presented in Holter monitor during the 3 to 5 years follow-up period. Six gene variants were found including a novel missense mutation of base C to T, named Arg965 Cys (R965C), which located in 965 codon of the 17 exon in SCN5A, and five SCN5A polymorphisms including A29A (c.87A>G), R1193Q (c.3578G>A), D1819D (c.5457T>C), exon11 -24G>A, exon23 +4A>G.

CONCLUSIONS

SCN5A mutation is related to fever-induced Brugada ECG pattern. However, individuals with Brugada ECG pattern induced by fever bear low risk of malignant arrhythmia and SCD during fibrile state and follow up in this small patient cohort.