Case Report: Rare Variant of Masquerading Right Bundle Branch Block
Keywords:
Masquerading right bundle branch block, electrocardiogram, cardiac conduction disordersAbstract
Masquerading bundle branch block, also referred to as disguised bundle branch block, is an electrocardiographic pattern characterized by right bundle branch block in the horizontal plane leads associated with a left bundle branch block morphology in the frontal plane leads. It occurs predominantly in elderly patients and in those with structural heart disease. The main clinical presentations are syncope and heart failure. We present a 73-year-old patient with three syncopal episodes and no symptoms of heart failure. The electrocardiogram revealed a mixed or global variant of masquerading right bundle branch block with a normal echocardiogram. The possibility of an electrophysiological study and cardiac resynchronization therapy was considered
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