Abstract
A young man with baseline early repolarization was initiated on flecainide and diltiazem for symptomatic atrial arrhythmias. A treadmill stress test induced a type 1 Brugada electrocardiogram pattern at higher heart rates. Flecainide was discontinued. Genetic testing revealed no SCN5A mutations, and a 3-generation pedigree revealed no events of concern. In this case report, we review the use-dependent properties of flecainide. We also discuss how this property can be exploited during exercise stress testing to provoke the diagnostic type 1 Brugada pattern at higher heart rates.