Atrial Flutter

Excerpt

Supraventricular arrhythmias are a diverse group of atrial arrhythmias. Atrial fibrillation and atrial flutter are the most common of these atrial arrhythmias, and the other less common supraventricular arrhythmias are atrial tachycardias, atrioventricular reentrant tachycardia, atrioventricular nodal tachycardia, and others (see Image. Atrial Flutter, ECG). This topic summarizes the management of atrial flutter.

Atrial flutter is 1 of the most common arrhythmias. It is characterized by an abnormal cardiac rhythm that is fast, with an atrial rate of 300 beats/min and a ventricular rate that can be fixed or variable that can, causing palpitations, fatigue, syncope, and embolic phenomenon.

Atrial flutter is a macro-reentrant tachycardia and, depending on the site of origin, can be a typical or atypical atrial flutter. Electrocardiographic findings of atrial flutter are flutter waves without an isoelectric line between the QRS complex. The electrical axis of the flutter waves can help determine the atrial flutter's origin.

Typical or cavotricuspid isthmus (CTI) dependent is the most common type of atrial flutter; this rhythm originates in the right atrium at the level of the tricuspid valve annulus. Typical atrial flutter is seen in the electrocardiogram as continuous negative modulation in inferior leads (II, III, and AVF) and flat atrial deflections in leads I and aVL; this is due to the way of propagation and activation of the macro-reentrant circuit as described in the pathophysiology section.

The atypical atrial flutter is independent of the CTI, and the arrhythmia's origin can be in the right or left atrium. Less commonly, atrial activation can be clockwise; thus, electrocardiographic appearance is different; one cannot differentiate it easily from non-isthmus-dependent atrial flutter.