Atrial flutter

Atrial flutter ( AFL ) is a supraventricular arrhythmia characterized by a fast atrial rate with a fixed or variable ventricular rate.

First described in 1887 by Mac WIlliam as faradic stimulation of the auricles which sets them into rapid flutter The atria depolarize at a regular rate of 250-350 beats / minute ( typically 300 beats ) The AV node cannot conduct at this high rate -this means that the ventricle may contract at 150 BPM( 2 :1 block ) and the ventricular rate may remain fixed 2 : 1 block is the most common one seenby extension if the atrial rate is 3003 : 1 conduction results in a VR of 100 BPM4 :1 in a rate of 75 BPM and5 :1 in a rate of 60 BPM1 : 1 conduction is rare but possible if a bypass tract is present This block may vary from moment to moment and can cause an irregular ventricular rhythm - this is called atrial flutter with variable conduction ( this can be difficult to distinguish from atrial fibrillation ) Various types have been described depending on the location of the short-circuit and the direction of the re-entry circuit Typical atrial flutter...