Rizo RGO

Language: Spanish
References: 21
Page: 266-270
PDF size: 419.80 Kb.

ABSTRACT

ST alternans reflects changes in action potential duration with increased electrical heterogeneity proportional to the alternation intensity. Although the mechanisms of ST and T alternans are still largely unknown, four mechanisms have been proposed: a) calcium overload, b) effect of chemicals from sustained ischemia, c) stimulation of the 5-HTreceptor and d) inhomogeneous blockade of sodium channels. Propafenone is a class IC sodium channel blocker, frequently used in the pharmacological cardioversion of atrial fibrillation, and has a use-dependence of heart rate phenomenon that can induce a Brugada pattern and electrical alternans. In this article, a clinical case demonstrating these two phenomena is presented.

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