Accessory Pathway-Mediated Tachycardias: Precision Electrocardiology Through Standard and Advanced Electrocardiogram Recording Techniques

摘要

Reentry is the pathophysiologic mechanism behind accessory pathway (AP)-mediated arrhythmias. A reentry is a circuit where continuous propagation can be functionally or anatomically determined. A functional reentry does not need a well-defined anatomic circuit, and the arrhythmia is principally maintained by the refractory period of the myocardium: the head of the activation wave immediately follows the tail of the previous beat and there is no excitable gap in the circuit. In contrast, the anatomic reentry as in AP-mediated arrhythmias is based on a well-determined circuit where its boundaries determine the path where the activation wave can propagate; in this type of circuit, an excitable gap usually exists between the head and the tail of the activation wave front. The Mines law states that, to maintain a reentry, the wavelength (velocity times refractory period) must be shorter than the circuit length.