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Sinus & atrial rhythms

Atrial flutter

Also calledAFL · A-flutter · aflutter · atrial flutter

Definition

A macroreentrant atrial tachycardia producing regular flutter waves; in typical cavotricuspid isthmus-dependent flutter they form a sawtooth pattern that is negative in the inferior leads (II, III, aVF) and positive in V1. The atrial rate is about 250 to 350 per minute (typically near 300, and slower with antiarrhythmic drugs or atrial scarring). Atrioventricular conduction is typically 2:1, giving a regular ventricular rate near 150 bpm; 4:1 is also common, and variable conduction makes the ventricular rhythm irregular.

Clinical noteA regular tachycardia near 150 bpm is a classic clue to atrial flutter with 2:1 conduction, in which the non-conducted flutter waves are often merged with, or mistaken for, T waves.

See it on 12-lead ECGsAtrial flutter in Rhythm Foundations: examples to step through, and how to identify it

Sources

  1. Page RL, Joglar JA, Caldwell MA, et al. 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia. Circulation. 2016;133(14):e506-e574. doi.org/10.1161/CIR.0000000000000311
  2. Goodacre S, Irons R. ABC of clinical electrocardiography: atrial arrhythmias. BMJ. 2002;324(7337):594-597. doi.org/10.1136/bmj.324.7337.594

Last reviewed 2 October 2026. Every definition in the EKG Dictionary cites the guideline, consensus statement or original paper it comes from.

More in Sinus & atrial rhythms

Atrial fibrillation Atrial tachycardia AV nodal reentrant tachycardia (AVNRT) AV reentrant tachycardia (AVRT) Multifocal atrial tachycardia Paroxysmal SVT Premature atrial contraction (PAC) Sick sinus syndrome Sinoatrial exit block Sinus bradycardia Sinus pause Sinus tachycardia Supraventricular tachycardia (SVT) Wandering atrial pacemaker

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