Ajmaline Challenge in Young Individuals with Suspected Brugada Syndrome

Abstract

The clinical characteristics and the results of ajmaline challenge in young individuals with suspected Brugada syndrome (BS) have not been systematically investigated. Among a larger series of patients included in the BS database of our Department, 179 patients undergoing ajmaline challenge were included in the study and categorized in two groups according to age: group 1 (<18 years old) and group 2 (≥18 years old). Clinical features and results of the ajmaline challenge of each group were compared. Young individuals were more often asymptomatic compared to adult patients (P = 0.002). They showed a higher number of normal ECGs (P = 0.023), a lower percentage of Brugada type II electrocardiographic pattern compared to the adult population (P = 0.011), and a comparable amount of spontaneous Brugada type III electrocardiographic pattern (P = 0.695). Ajmaline provoked a higher degree of intraventricular conduction delay (P = 0.002) and higher degree of prolongation of the ventricular repolarization phase (P = 0.013) in young individuals but its pro-arrhythmic risk was comparable in the two groups (P = 0.684). Furthermore, inducibility of ventricular arrhythmias in young patients with a positive ajmaline test was comparable to that of the adults with a positive ajmaline test (P = 0.694). The present study demonstrates the low-risk profile of the ajmaline test in young patients when performed by experienced physicians and nurses in an appropriate environment.