Atrial tachycardia
Also calledAT · atrial tach · atrial tachycardia · ectopic atrial tachycardia · EAT · focal atrial tachycardia
Definition
A supraventricular tachycardia arising from a localized atrial site outside the sinus node (by automaticity, triggered activity or microreentry), with regular, organized atrial activity: discrete P waves whose morphology differs from the sinus P wave, typically separated by an isoelectric baseline. The atrial rate is usually 100 to 250 bpm. The AV node may conduct 1:1 or with block, so the ventricular rate can be lower than the atrial rate. Multifocal atrial tachycardia is a distinct variant defined by an irregular rhythm with at least 3 P-wave morphologies and an atrial rate over 100 bpm.
Sources
- 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
- Samesima N, God EG, Kruse JCL, et al. Brazilian Society of Cardiology guidelines on the analysis and issuance of electrocardiographic reports - 2022. Arq Bras Cardiol. 2022;119(4):638-680. doi.org/10.36660/abc.20220623
- 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.