Medical Research: What is the background for this study? What are the main findings?
Dr. Conte: The evolution of Brugada syndrome from pediatric to adult age has not been previously evaluated. It has been shown that the electrocardiographic phenotype of Brugada syndrome do not manifest during childhood in the large majority of cases. Drug challenge with ajmaline is recommended to unmask the diagnostic electrocardiogram in patients with family history of Brugada syndrome and normal electrocardiograms. However, the ideal age to perform such screening has not been established yet. With this study we aimed to investigate the clinical value of repeating ajmaline challenge after puberty in pediatric family members with an initial negative drug test. Repeat ajmaline challenge after puberty unmasked Brugada syndrome in 23% of family members with a previously negative drug test. Of the newly positive patients, 30% developed symptoms, 10% ventricular fibrillation and 10% spontaneous Brugada type 1 electrocardiogram.
Medical Research: What should clinicians and patients take away from your report?
Dr. Conte: Our study highlights the existence in Brugada syndrome of an age-dependent response to sodium channel blocker administration. These findings support the need for continuous monitoring of patients and family members with Brugada syndrome, even those considered at low risk at a pediatric age. A family member with a normal electrocardiogram who develops symptoms after puberty should be always investigated with an ajmaline test to rule out Brugada syndrome even if he/she had a negative drug test performed before puberty.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Conte: Our data underline the potential role of hormones as causative factors in determining the post-pubertal response to ajmaline in patients with the syndrome. Further specific studies conducted on larger populations of patients are needed to confirm our results.
Conte G, de Asmundis C, Ciconte G, et al. Follow-up From Childhood to Adulthood of Individuals With Family History of Brugada Syndrome and Normal Electrocardiograms. JAMA. 2014;312(19):2039-2041. doi:10.1001/jama.2014.13752.