Spontaneous alternans in Brugada ST-segment morphology within minutes.

Brugada syndrome is an inherited, life-threatening, cardiac channelopathy where the electrocardiogram (ECG) characteristically depicts a classic pattern of complete or incomplete right bundle-branch block with ST-segment elevation in the right precordial leads V(1) to V(3). These, almost inalienable, ECG patterns may be dynamic, where changes may resolve to baseline or one particular type may evolve into another. Such alternans has been described with fever, electrolyte imbalances, atrial pacing, glucose and/or insulin administration, psychotropic drugs, beta-adrenergic blocker use, class IA and IC antiarrhythmic provocation testing, such as with ajmaline, procainamide, or flecainide, and even large meals, that is, "full stomach sign." However, spontaneous alternans between the different types of Brugada ECG patterns (types) have not been reported within minutes, in the absence of previously described precipitating factors. We present a novel case where classic, type 2, Brugada-like ECG pattern evolved spontaneously to type 1 before returning to type 2 within minutes of presentation.