Atrial ectopic tachycardia (AET) is a rare arrhythmia; however, it is the most common form of incessant supraventricular tachycardia (SVT) in children. Atrial ectopic tachycardia is believed to be secondary to increased automaticity of a nonsinus atrial focus or foci. This arrhythmia, which is also known as ectopic atrial tachycardia or automatic atrial tachycardia, has a high association with tachycardia-induced cardiomyopathy. Atrial ectopic tachycardia is often refractory to medical therapy and is not usually responsive to direct current (DC) cardioversion.
The diagnosis of atrial ectopic tachycardia is based on the presence of a narrow complex tachycardia (in the absence of aberrancy or preexisting bundle branch block) with visible P waves at an inappropriately rapid rate. The rates range from 120 to 300 beats per minute (bpm) and are typically higher than 200 bpm, although physiologic rates may be observed (see Electrocardiography).
Patients with atrial ectopic tachycardia may present with circulat ory collapse similar to patients with cardiomyopathy. Immediate rate control is desired in these cases. Three options are available for long-term treatment of patients with atrial ectopic tachycardia: medication to suppress the arrhythmia or control the ventricular response, catheter ablation, or, uncommonly, surgery (see Treatment and Management).