ABSTRACT
In the typical form of atrial flutter the atria discharge at a rate between 240 and 350 beats/min. Usually, the atrial rate is close to 300 beats/min. The arrhythmia is caused by a re-entrant circuit within the right atrium. Usually, the impulse circulates in an inferior direction along the lateral border of the right atrium and returns in a superior direction along the interatrial septum (Figure 7.1). The left atrium is activated by the impulses arising from the right atrium.
