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Return of the same impulse into a zone of heart muscle that it has recently activated, sufficiently delayed that the zone is no longer refractory, as seen in most ectopic beats, reciprocal rhythms, and most tachycardias.
reentry phenomenonCardiology The reexcitation of a region of the heart by a single electrical impulse, which may cause ectopic beats or tachyarrhythmia; RE is the common cause of paroxysmal atrial or supraventricular arrhythmia, which is coupled to premature ventricular depolarization
re·en·try phe·nom·e·non(rē-en'trē fĕ-nom'ĕ-non)
The return of a cardiac impulse to an area of muscle that it has already activated, after the refractory period of the area has expired, resulting in one or more ectopic beats or a sustained arrhythmia.