Which type of arrhythmia is characterized by a rapid beating of the heart due to reentry circuits?

The type of arrhythmia characterized by a rapid beating of the heart due to reentry circuits is supraventricular tachycardia. In this condition, the heart's electrical impulses are disrupted, leading to a reentrant circuit that causes the heart to beat quickly. This means that electrical signals travel in an abnormal loop within the heart, effectively increasing the heart rate to a level above that of normal sinus rhythm.

Supraventricular tachycardia typically originates above the ventricles, often within the atria or the AV node, making it distinct from other arrhythmias such as atrial fibrillation or ventricular tachycardia. In cases of atrial fibrillation, multiple reentrant circuits contribute to an irregularly rapid heartbeat, but it lacks the organized, rapid repetitive circuit characteristic of supraventricular tachycardia. On the other hand, ventricular tachycardia occurs due to reentry circuits in the ventricles themselves, leading to a different presentation and more serious implications. Atrial flutter also involves reentrant circuits, but it has a different mechanism and a characteristic "sawtooth" pattern seen on an ECG.

Thus, the defining feature of supraventricular tachycardia is the reentry