---
title: Focal atrial tachycardia
description: What focal atrial tachycardia and its multifocal form are, why a focus in the atrium sets a fast rhythm, how it is recognised on the ECG, which treatment approaches clinical guidelines describe and when urgent help is needed.
type: disease
preset: focal-atrial-tachycardia
aliases:
  - ectopic atrial tachycardia
  - focal AT
  - multifocal atrial tachycardia
  - chaotic atrial tachycardia
  - MAT
sources:
  - tier: guideline
    org: minzdrav-rf
    title: Наджелудочковые тахикардии
    year: 2025
    doi: 10.15829/1560-4071-2025-6448
    url: https://cr.minzdrav.gov.ru/view-cr/619_3
  - tier: guideline
    org: esc
    title: 2019 Рекомендации ESC по лечению пациентов с наджелудочковыми тахикардиями
    year: 2020
    doi: 10.15829/1560-4071-2020-3864
    url: https://doi.org/10.15829/1560-4071-2020-3864
  - tier: reference
    org: msd-manuals
    title: Ectopic Supraventricular Arrhythmias (MSD Manual Professional Version)
    year: 2024
    url: https://www.msdmanuals.com/professional/cardiovascular-disorders/specific-cardiac-arrhythmias/ectopic-supraventricular-arrhythmias
  - tier: review
    title: 'Management of patients with atrial tachycardia: a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, endorsed by the Heart Rhythm Society (HRS), the Asia Pacific Heart Rhythm Society (APHRS), the Latin American Heart Rhythm Society (LAHRS), and the Association for European Paediatric and Congenital Cardiology (AEPC)'
    year: 2025
    doi: 10.1093/europace/euaf324
    url: https://doi.org/10.1093/europace/euaf324
sources_checked: 2026-10-14
review: null
---

Focal atrial tachycardia (AT) is a fast rhythm set not by the sinus node but by a separate focus in the wall of an atrium.<Cite n={[2, 3, 4]} /> It is one of the types of supraventricular tachycardia.<Cite n={1} /> Episodes in which the impulse circles through a loop involving the AV node are covered in the article on [supraventricular tachycardia](../supraventricular-tachycardia/), and atrial tachycardia with a large circuit of excitation in the article on [atrial flutter](../atrial-flutter/).<Cite n={1} /> A fast rhythm from the sinus node itself is sinus tachycardia; one unusual form of it is described in the article on [inappropriate sinus tachycardia](../inappropriate-sinus-tachycardia/).<Cite n={1} />

There is also multifocal atrial tachycardia: then there are several foci, and they fire at random.<Cite n={[1, 3]} /> The sections on causes, symptoms, diagnosis and treatment have separate paragraphs about it.

<Diagram name="focal-atrial-tachycardia">
  <p slot="normal">
    Normally the <Structure id="sa-node">sinus node</Structure> sets the rhythm, and the P waves on
    the ECG have the usual, sinus shape.<Cite n={[1, 3]} /> How the impulse then travels across the
    atria to the <Structure id="av-node">AV node</Structure> and the ventricles is explained in the
    article on the [conduction system of the heart](../../anatomy/conduction-system/).
  </p>
  <p slot="disease">
    In focal atrial tachycardia the impulses are sent rapidly by a single focus in an atrium,
    separate from the sinus node, and the wave of excitation spreads from it in all directions over
    both atria.<Cite n={[2, 4]} /> The rhythm is fast and usually regular.<Cite n={3} /> How many
    impulses reach the ventricles depends on conduction through the AV node.<Cite n={[1, 2]} />
  </p>
</Diagram>

## Why it happens

<Patient>

The cells of the focus fire rapidly.<Cite n={3} /> There are three mechanisms: abnormal automaticity, triggered activity and re-entry — a very small circuit of excitation.<Cite n={[1, 3]} /> The focus can arise anywhere in the atria, but it is most often found at the crista terminalis, around the rings of the mitral and tricuspid valves and at the openings of the pulmonary veins.<Cite n={[1, 2]} />

This tachycardia occurs both in a healthy heart and in heart disease.<Cite n={1} /> The MSD Manual says that it usually occurs in people with a structural heart disorder.<Cite n={3} />

It can be favoured by alcohol and recreational drugs, endocrine diseases such as [thyrotoxicosis](../thyrotoxic-heart-disease/) and [phaeochromocytoma](../pheochromocytoma/), excess weight, sleep apnoea, and disturbances of the salt and acid–base balance of the blood, including low potassium.<Cite n={1} /> Another cause is an overdose of cardiac glycosides, medicines used to treat the heart.<Cite n={[1, 3]} /> According to MSD, irritation of the atria, for example in [pericarditis](../pericarditis/), can also cause the tachycardia.<Cite n={3} />

Multifocal AT occurs most often in people with long-standing lung disease and "pulmonary heart disease" (cor pulmonale), for example in chronic obstructive pulmonary disease.<Cite n={[1, 3]} /> Less often it complicates [heart failure](../heart-failure/), an acute [heart attack](../myocardial-infarction/) or [pulmonary hypertension](../pulmonary-hypertension/), or occurs with a low magnesium level or an overdose of certain medicines.<Cite n={[1, 2]} /> It is also seen in healthy children under one year old, and with a healthy heart the outlook is good.<Cite n={1} />

</Patient>

<Student>

The Russian Ministry of Health guideline defines focal AT as an organised atrial rhythm with a rate of 100 to 250–300 per minute with regular or irregular conduction to the ventricles; the ESC defines it as an organised atrial rhythm ≥100 per minute arising from a discrete origin and spreading centrifugally over both atria.<Cite n={[1, 2]} /> The ventricular rate depends on AV nodal conduction.<Cite n={[1, 2]} /> According to MSD, the heart rate is usually 150–200 per minute, but with a very fast atrial rate, AV nodal dysfunction or cardiac glycoside toxicity there may be AV block with a slower ventricular rate.<Cite n={3} /> The EHRA consensus defines focal AT as atrial activation emanating from a discrete focus separate from the sinus node and spreading centrifugally.<Cite n={4} />

According to the Ministry guideline and the ESC, the prevalence of focal AT is 0.34% in asymptomatic patients under 50 and 0.46% in patients with symptomatic arrhythmia.<Cite n={[1, 2]} /> According to the ESC, no difference in prevalence between men and women has been found.<Cite n={2} />

According to the Ministry guideline, multifocal AT is usually associated with significant structural disease of the atria (atrial cardiomyopathy); its causes include overdose of sympathomimetics, cardiac glycoside toxicity and other toxic influences, including hypomagnesaemia.<Cite n={1} /> The ESC adds coronary artery disease and valvular heart disease.<Cite n={2} /> According to MSD, accompanying hypoxia and acidosis are particularly important in lung disease.<Cite n={3} />

</Student>

<HeartModel highlight={['right-atrium', 'left-atrium']} />

## Symptoms

<Patient>

Usually these are episodes of a fast heartbeat (palpitations); there may be shortness of breath, chest discomfort or pain and dizziness, and rarely feeling faint or fainting.<Cite n={[1, 2, 3]} /> Episodes are more often short but can also be prolonged.<Cite n={[1, 2]} /> Short episodes are often found on [Holter monitoring](../../diagnostic/holter-monitoring/), and the person usually does not notice them.<Cite n={1} />

The outlook is usually good.<Cite n={1} /> But if the tachycardia hardly ever stops, it can weaken the heart: the ventricles enlarge and pump less well, up to heart failure.<Cite n={[1, 3]} /> This is called arrhythmia-induced cardiomyopathy; in many cases it improves partly or fully once the arrhythmia is eliminated.<Cite n={1} />

Multifocal AT is often not felt at all: the pulse is not very fast.<Cite n={1} />

</Patient>

<Student>

The Russian Ministry of Health guideline defines arrhythmia-induced cardiomyopathy (AiCM) as ventricular dilatation and reduced systolic function that most likely arose or worsened because of an arrhythmia; in focal AT it can result from incessant, recurring forms.<Cite n={1} /> According to the ESC, in patients under 18 focal AT is the most common cause of tachycardia-induced cardiomyopathy.<Cite n={2} /> In multifocal AT, AiCM develops rarely.<Cite n={1} />

</Student>

## How it is diagnosed

<Patient>

The key step is to record an [ECG](../../diagnostic/ecg/) during an episode: in focal AT the P waves differ in shape from the usual, sinus ones.<Cite n={[1, 2, 3]} /> If episodes are short, the rhythm is recorded for a long time: with 24-hour or multi-day Holter monitoring, or with a wearable or implantable recorder.<Cite n={1} /> [Echocardiography](../../diagnostic/echocardiography/) is done to assess the size and function of the heart chambers, and blood tests, including the hormone that controls the thyroid gland (TSH).<Cite n={1} />

From the shape of the P wave the doctor can suggest which atrium, and which part of it, holds the focus.<Cite n={[1, 2]} /> On an ordinary ECG it can be hard to tell focal tachycardia from tachycardia with a large circuit of excitation.<Cite n={[1, 2]} />

In multifocal AT the rhythm is irregular and the P waves have different shapes, so it is important to distinguish it from [atrial fibrillation](../atrial-fibrillation/); a 12-lead ECG is needed for this.<Cite n={[1, 2, 3]} />

</Patient>

<Student>

The key sign is P′ waves that differ from sinus P waves, with isoelectric intervals between them; depending on AV conduction and rate they may be hidden in the QRS complexes or T waves.<Cite n={[1, 2]} /> Monomorphic P′ waves with a stable cycle length help exclude AF; the diagnosis is obvious when P′ waves clearly outnumber QRS complexes.<Cite n={[1, 2]} /> A gradual rise in rate after onset ("warm-up") and a gradual fall before termination ("cool-down") point to increased activity of an ectopic focus and are not typical of AVNRT and AVRT.<Cite n={1} /> If the P waves do not differ from sinus P waves, the ESC advises considering sinus tachycardia, including inappropriate sinus tachycardia, sinus node re-entrant tachycardia, or focal AT arising close to the sinus node.<Cite n={2} />

Localisation by P′: a negative P′ in I and aVL points to the left atrium; a negative P′ in V1 to the lateral wall of the right atrium, and a biphasic or positive one to the interatrial septum; negative P′ waves in the inferior leads point to an inferior (caudal) source, positive ones to a superior source.<Cite n={1} /> Distinguishing focal AT from macro-re-entrant AT on the surface ECG is not always possible; an isoelectric line does not exclude re-entry, especially in significant heart disease or after extensive catheter ablation.<Cite n={[1, 2]} /> The most common macro-re-entrant AT is atrial flutter.<Cite n={1} />

Multifocal AT is diagnosed when there are P′ waves of three or more morphologies.<Cite n={[1, 2, 3]} /> According to the Ministry guideline, they have different coupling intervals, and the PP, PR and RR intervals vary.<Cite n={1} /> Unlike AF, there is an isoelectric line between the P waves.<Cite n={2} />

</Student>

## How it is treated

<Patient>

If during an episode the blood pressure drops sharply, the person loses consciousness or has chest pain and severe shortness of breath (an unstable condition), doctors restore the rhythm with electrical cardioversion — a shock synchronised with the heartbeat.<Cite n={[1, 2]} /> But the tachycardia often comes back after it.<Cite n={1} /> In a stable condition doctors try to stop the episode with intravenous medicines that slow conduction through the AV node; among them are beta-blockers and calcium channel blockers, which can stop the tachycardia or slow the ventricles.<Cite n={[1, 2]} /> If the tachycardia was caused by cardiac glycosides, the doctor stops that medicine.<Cite n={3} />

If episodes keep coming back, especially if the tachycardia is almost continuous or has already weakened the heart, catheter ablation is considered the treatment of choice: the doctor finds the focus at the site of earliest activation and destroys it precisely.<Cite n={[1, 2, 3]} /> It is done in experienced centres.<Cite n={1} />

If ablation is undesirable or not possible, long-term medicines are prescribed; the Russian Ministry of Health guideline names calcium channel blockers and beta-blockers as first-line.<Cite n={1} /> There are few studies of long-term treatment.<Cite n={2} /> Medicines are chosen and prescribed by a doctor; do not start, stop or change them on your own.

In multifocal AT the main thing is to treat the underlying disease, most often a lung disease.<Cite n={[1, 2, 3]} /> Antiarrhythmic drugs help little; treatment often comes down to medicines that slow the ventricles.<Cite n={[1, 2]} />

</Patient>

<Student>

The Russian Ministry of Health guideline recommends synchronised electrical cardioversion for focal AT with haemodynamic instability, noting that the tachycardia often recurs.<Cite n={1} /> According to the ESC, if the arrhythmia is incessant and due to enhanced automaticity, it starts again, and repeated shocks are not appropriate.<Cite n={2} /> The ESC allows acute treatment to start with beta-blockers or calcium channel blockers, which may terminate the AT or slow the ventricular response.<Cite n={2} /> In the ESC and Ministry recommendation tables for haemodynamically stable patients, they are the second step, if a drug that briefly blocks AV conduction has not helped.<Cite n={[1, 2]} />

The Ministry guideline recommends catheter ablation of the focus, especially for recurrent AT or AiCM, in experienced centres with navigation mapping systems (class I, level B on the ESC scale); ablation success is 75–100%.<Cite n={1} /> Mapping and ablation are based on locating the site of earliest activation.<Cite n={2} /> MSD calls transcatheter ablation effective, reasonably safe and the preferred approach for chronic prophylaxis.<Cite n={3} /> Data on long-term drug therapy are limited; beta-blockers and non-dihydropyridine calcium channel blockers may be effective with few side effects.<Cite n={[1, 2]} />

In multifocal AT the ESC considers antiarrhythmic drugs ineffective, and the Ministry guideline considers them generally insufficiently effective.<Cite n={[1, 2]} /> For patients with LV systolic dysfunction due to recurrent multifocal AT refractory to drug therapy, the ESC recommends AV node ablation followed by permanent pacing (IIa C).<Cite n={2} />

</Student>

## When to call an ambulance

The outlook in focal AT is usually good.<Cite n={1} /> But episodes can bring chest pain, shortness of breath, feeling faint and fainting, and an unstable condition needs urgent electrical cardioversion.<Cite n={[1, 2]} />

**Call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK)** if an episode of fast heartbeat comes with fainting or feeling faint: sudden darkening of vision, weakness, dizziness, cold sweat.<Cite n={1} /> The Russian Ministry of Health guideline also names chest pain, acute heart failure with severe shortness of breath and a suspected heart attack as signs of an unstable condition in which the person must be admitted to hospital — call an ambulance in these cases too.<Cite n={1} />

**See a doctor** if episodes of palpitations keep coming back or the feeling of a fast pulse hardly goes away: continuous tachycardia can weaken the heart.<Cite n={[1, 3]} />

As with any heart or blood vessel condition, call an ambulance for fainting, chest pain or severe breathlessness: this is the site's general safety rule, repeated at the bottom of every page.

<Quiz />