AIMS: The diagnostic ECG pattern in Brugada syndrome (BS) can transiently normalize and may be unmasked by sodium channel blockers such as ajmaline. Proarrhythmic effects of the drug have been well documented in the literature. A detailed protocol for the ajmaline challenge in Brugada syndrome has not yet been described. Therefore, we prospectively studied the risks of a standardized ajmaline test. METHODS AND RESULTS: During a period of 60 months, 158 patients underwent the ajmaline test in our institution. Ajmaline was given intravenously in fractions (10mg every two minutes) up to a target dose of 1mg/kg. In 37 patients (23%) the typical coved-type ECG pattern of BS was unmasked. During the test, symptomatic VT appeared in 2 patients (1.3%). In all other patients, the drug challenge did not induce VT if the target dose, QRS prolongation >30%, presence/appearance of the typical ECG, or the occurrence of premature ventricular ectopy were considered as end points of the test. A positive response to ajmaline was induced in 2 of 94 patients (2%) with a normal baseline ECG, who underwent evaluation solely for syncope of unknown origin. CONCLUSION: The ajmaline challenge using a protocol with fractionated drug administration is a safe method to diagnose BS. Because of the potential induction of VT, it should be performed under continuous medical surveillance with advanced life-support facilities. Due to the prognostic importance all patients with aborted sudden death or unexplained syncope without demonstrable structural heart disease and family members of affected individuals should presently undergo drug testing for unmasking BS.
AIMS: The diagnostic ECG pattern in Brugada syndrome (BS) can transiently normalize and may be unmasked by sodium channel blockers such as ajmaline. Proarrhythmic effects of the drug have been well documented in the literature. A detailed protocol for the ajmaline challenge in Brugada syndrome has not yet been described. Therefore, we prospectively studied the risks of a standardized ajmaline test. METHODS AND RESULTS: During a period of 60 months, 158 patients underwent the ajmaline test in our institution. Ajmaline was given intravenously in fractions (10mg every two minutes) up to a target dose of 1mg/kg. In 37 patients (23%) the typical coved-type ECG pattern of BS was unmasked. During the test, symptomatic VT appeared in 2 patients (1.3%). In all other patients, the drug challenge did not induce VT if the target dose, QRS prolongation >30%, presence/appearance of the typical ECG, or the occurrence of premature ventricular ectopy were considered as end points of the test. A positive response to ajmaline was induced in 2 of 94 patients (2%) with a normal baseline ECG, who underwent evaluation solely for syncope of unknown origin. CONCLUSION: The ajmaline challenge using a protocol with fractionated drug administration is a safe method to diagnose BS. Because of the potential induction of VT, it should be performed under continuous medical surveillance with advanced life-support facilities. Due to the prognostic importance all patients with aborted sudden death or unexplained syncope without demonstrable structural heart disease and family members of affected individuals should presently undergo drug testing for unmasking BS.
Authors: Kui Hong; Josep Brugada; Antonio Oliva; Antonio Berruezo-Sanchez; Domenico Potenza; Guido D Pollevick; Alejandra Guerchicoff; Kiyotaka Matsuo; Elena Burashnikov; Robert Dumaine; Jeffrey A Towbin; Vladislav Nesterenko; Pedro Brugada; Charles Antzelevitch; Ramon Brugada Journal: Circulation Date: 2004-11-01 Impact factor: 29.690
Authors: Christian Wolpert; Constanze Echternach; Christian Veltmann; Charles Antzelevitch; George P Thomas; Susanne Spehl; Florian Streitner; Juergen Kuschyk; Rainer Schimpf; Karl K Haase; Martin Borggrefe Journal: Heart Rhythm Date: 2005-03 Impact factor: 6.343
Authors: Sergio Dubner; Damián Azocar; Sebastián Gallino; Alfonso Rafael Cerantonio; Sergio Muryan; Juan Medrano; Carlos Bruno Journal: Ann Noninvasive Electrocardiol Date: 2013-05 Impact factor: 1.468
Authors: Jeffrey T Mindrebo; Charisse M Nartey; Yoshiya Seto; Michael D Burkart; Joseph P Noel Journal: Curr Opin Struct Biol Date: 2016-09-21 Impact factor: 6.809