Atrial flutter is an AV node-independent intra-atrial macro-reentry rhythm, in which the atrial anatomy sustains a loop of continuous depolarization, often around the tricuspid valve annulus in the right atrium. Atrial flutter can be paroxysmal or chronic and may be associated with extremely rapid ventricular response rates. Variable degrees of AV block often modify AV conduction, which changes between 1:1 and 3:1 or 2:1. Atrial flutter often induces electrical remodeling and thereby can serve as a precursor to atrial fibrillation.

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