---
title: Early repolarisation
description: How the common and usually harmless early repolarisation pattern on the ECG differs from the rare early repolarisation syndrome, how they are detected, which treatment approaches guidelines describe and when to call an ambulance.
type: disease
aliases:
  - early repolarization syndrome
  - early repolarization pattern
  - early repolarisation syndrome
  - early repolarisation pattern
  - early repolarization
  - ERS
  - ERP
  - J-wave syndrome
sources:
  - tier: guideline
    org: esc
    title: 2022 ESC Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death
    year: 2022
    doi: 10.1093/eurheartj/ehac262
    url: https://doi.org/10.1093/eurheartj/ehac262
  - tier: guideline
    org: minzdrav-rf
    title: Желудочковые нарушения ритма сердца. Внезапная сердечная смерть
    year: 2025
    doi: 10.15829/1560-4071-2025-6670
    url: https://cr.minzdrav.gov.ru/view-cr/569_2
  - tier: reference
    org: msd-manuals
    title: Early Repolarization Syndrome (MSD Manual Professional Version)
    year: 2026
    url: https://www.msdmanuals.com/professional/cardiovascular-disorders/arrhythmogenic-cardiac-disorders/early-repolarization-syndrome
  - tier: reference
    org: msd-manuals
    title: Athlete's Heart (Exercise-Induced Cardiac Remodeling) (MSD Manual Professional Version)
    year: 2026
    url: https://www.msdmanuals.com/professional/cardiovascular-disorders/sports-and-the-heart/athlete-s-heart
  - tier: reference
    org: statpearls
    title: ST Segment
    year: 2023
    url: https://pubmed.ncbi.nlm.nih.gov/29083566/
sources_checked: 2026-10-14
review: null
---

"Early repolarisation" covers two different things. The **early repolarisation pattern** is a feature of the [ECG](../../diagnostic/ecg/): the J point, where the QRS complex turns into the ST segment, is raised in the inferior or lateral leads.<Cite n={[1, 3]} /> This pattern is common, and in a person without symptoms and without sudden deaths in the family it needs neither further tests nor treatment.<Cite n={[1, 3]} /> **Early repolarisation syndrome** is a genetic disorder of the ion channels of heart cells (a channelopathy): the term means the same pattern in a person who has had a dangerous ventricular arrhythmia or cardiac arrest.<Cite n={[1, 2, 3]} /> Each section below describes the pattern and the syndrome separately.

<Diagram name="early-repolarization-syndrome">
  <p slot="normal">
    The diagram shows one ECG complex. Normally the ST segment is an electrically neutral interval
    between the QRS complex and the T wave, and it usually runs along the baseline.<Cite n={5} /> The
    J point is where the QRS complex ends and the ST segment begins.<Cite n={3} />
  </p>
  <p slot="disease">
    In the early repolarisation pattern the J point is raised above the baseline in adjacent
    inferior or lateral leads; the end of the QRS complex may be notched or slurred, but this is not
    needed for the diagnosis.<Cite n={[1, 3]} /> The dashed line shows the usual ST segment and T
    wave for comparison. This pattern is common, and in a person without symptoms and without sudden
    deaths in the family it is most often a harmless finding that needs no treatment.<Cite n={[1, 3]} />
    The syndrome is diagnosed when a person with this pattern has had unexplained ventricular fibrillation or polymorphic ventricular tachycardia.<Cite n={[1, 3]} />
  </p>
</Diagram>

## Why it happens

<Patient>

**The pattern.** Early repolarisation on the ECG is common, especially in men, young people, athletes and Black people.<Cite n={3} /> In athletes, ST elevation consistent with early repolarisation counts as a normal finding if there are no symptoms and no family history of sudden death or inherited heart disease.<Cite n={4} /> More in the article on [athlete's heart](../athletes-heart/). Similar ECG changes also have other causes, for example a raised or very low body temperature, a low calcium level or a high potassium level in the blood.<Cite n={3} />

**The syndrome.** Early repolarisation syndrome is a disorder of the ion channels of heart cells, through which charged particles move into and out of the cells.<Cite n={[2, 3]} /> Because of it, the heart is prone to dangerous arrhythmias: [ventricular tachycardia](../ventricular-tachycardia/) and [ventricular fibrillation](../ventricular-fibrillation/).<Cite n={3} /> The syndrome appears to be inherited, but specific gene changes are rarely found.<Cite n={3} /> An arrhythmia episode can be brought on by a shortage of blood to the heart muscle (ischaemia).<Cite n={3} />

</Patient>

<Student>

**The pattern.** According to the MSD Manual, in a meta-analysis of studies in adults the prevalence of the early repolarisation pattern was 8.9%, with a study-specific range of 0.5% to 24.8%; it is more common in males, younger patients, athletes and Black people.<Cite n={3} /> At the same time, the pattern is substantially more common in survivors of apparently idiopathic ventricular fibrillation and is associated with a higher follow-up probability of sudden cardiac death.<Cite n={3} /> In a meta-analysis the relative risk of sudden cardiac death with an isolated pattern was 1.7, but the absolute increase in risk was only 70 per 100,000 patient-years.<Cite n={3} /> The Russian Ministry of Health guideline notes that in acute coronary syndrome early repolarisation is associated with an increased risk of ventricular arrhythmias and sudden cardiac death.<Cite n={2} />

**The syndrome.** The Russian Ministry of Health guideline lists early repolarisation syndrome among the congenital syndromes (channelopathies) in which ventricular arrhythmias occur without overt structural heart disease.<Cite n={2} /> According to the MSD Manual, the syndrome appears to result from mutations that produce a gain of function of outward potassium currents or a loss of function of inward sodium or calcium currents; this magnifies the transmural voltage gradients during the plateau phase of the action potential, which produces a J wave and J-point elevation on the ECG and predisposes to polymorphic VT that can degenerate into VF.<Cite n={3} /> The changes resemble those of [Brugada syndrome](../brugada-syndrome/) but appear in the inferior or lateral leads rather than the right precordial leads; both are grouped as J-wave syndromes.<Cite n={3} /> Disease-specific mutations are rarely identified, suggesting that the disorder is often polygenic.<Cite n={3} /> The MSD Manual estimates that the syndrome is responsible for 2 to 3% of cases of survived sudden cardiac death.<Cite n={3} /> Before a VT/VF episode the pattern may become more exaggerated; an episode may be precipitated by myocardial ischaemia.<Cite n={3} />

</Student>

## Symptoms

<Patient>

**The pattern** is a finding on the ECG. If a person with it has no symptoms and no sudden deaths in the family, no further tests are needed.<Cite n={3} />

**The syndrome** shows itself through ventricular arrhythmias, which can cause palpitations and cardiac arrest.<Cite n={3} /> Fainting can also happen but is uncommon, because ventricular tachycardia in this syndrome rarely stops on its own.<Cite n={3} />

</Patient>

<Student>

Early repolarisation syndrome predisposes to polymorphic VT, VF and sudden death.<Cite n={3} /> The arrhythmias cause palpitations and/or cardiac arrest; syncope may occur but is uncommon, because VT in this syndrome rarely self-terminates.<Cite n={3} />

</Student>

## How it is diagnosed

<Patient>

**The pattern** is found on the ECG: the J point is raised in adjacent inferior or lateral leads.<Cite n={[1, 3]} /> Changes in the ST segment can be a harmless variant or a sign of damage to the heart muscle, so a doctor reads the ECG.<Cite n={5} /> If there are no symptoms and no sudden deaths in the family, no further tests are needed; the European guideline advises against routinely examining people who have this pattern without symptoms.<Cite n={[1, 3]} /> If there has been a faint that looks like it was caused by an arrhythmia, or there are other risk features, the doctor may offer an implantable loop recorder for long-term ECG recording (more on long-term recording in the article on [ECG monitoring](../../diagnostic/holter-monitoring/)).<Cite n={1} />

**The syndrome**, according to the European guideline, is diagnosed when a person with this pattern has been resuscitated after unexplained ventricular fibrillation or polymorphic ventricular tachycardia.<Cite n={[1, 3]} /> The doctor also makes sure there is no structural heart disease.<Cite n={3} /> Close relatives of a person with the syndrome are advised to be examined, including with an ECG.<Cite n={[1, 3]} /> A genetic test may be considered, but gene changes are rarely found.<Cite n={[1, 3]} />

</Patient>

<Student>

**The pattern (ESC 2022).** It is recommended that the early repolarisation pattern is diagnosed as J-point elevation of ≥ 1 mm in two adjacent inferior and/or lateral ECG leads (I C).<Cite n={1} /> The MSD Manual specifies ≥ 1 mm (≥ 0.1 mV) in ≥ 2 contiguous inferior (II, III, aVF) or lateral (I, aVL, V4–V6) leads; a slurred or notched terminal QRS and ST elevation or depression may be present but are not necessary for the diagnosis.<Cite n={3} /> Clinical evaluation is not recommended routinely in asymptomatic subjects with the pattern (III C).<Cite n={1} /> An implantable loop recorder should be considered in individuals with the pattern and at least one risk feature or arrhythmic syncope (IIa C).<Cite n={1} />

**The syndrome (ESC 2022).** It is recommended that the syndrome is diagnosed in a patient resuscitated from unexplained VF/polymorphic VT in the presence of the pattern (I C).<Cite n={1} /> In a sudden cardiac death victim with a negative autopsy and medical chart review and an antemortem ECG showing the pattern, the diagnosis of the syndrome should be considered (IIa C).<Cite n={1} /> First-degree relatives should be considered for clinical evaluation for the pattern with additional high-risk features (IIa B); genetic testing in patients with the syndrome may be considered (IIb C).<Cite n={1} /> According to the MSD Manual, in addition to the pattern the diagnosis requires symptoms of VT/VF, cardiac arrest, presumed arrhythmic syncope or sustained VT in the absence of structural heart disease.<Cite n={3} /> The MSD Manual also describes the syndrome in the absence of other causes of early repolarisation (hyperthermia or hypothermia, hypocalcaemia, hyperkalaemia).<Cite n={3} /> High-risk ECG features according to the MSD Manual are J waves > 2 mm (0.2 mV), dynamic changes in the J point and a horizontal or descending ST segment; high-risk clinical features are these ECG features, a family history of sudden cardiac death before 40 years of age and a family history of early repolarisation syndrome.<Cite n={3} />

</Student>

## How it is treated

<Patient>

**The pattern** without symptoms and without sudden deaths in the family needs no treatment: the risk in such people is very low.<Cite n={3} /> An implantable cardioverter-defibrillator is not recommended for people who have only the pattern and no symptoms.<Cite n={1} /> The exception is rare people without symptoms whose ECG shows the pattern with high-risk features and who have had unexplained sudden deaths at a young age in the family: an arrhythmia specialist may discuss an ICD or drug treatment with them.<Cite n={[1, 3]} />

**The syndrome.** A person with the syndrome who has survived cardiac arrest is advised to have an implantable cardioverter-defibrillator (ICD).<Cite n={[1, 3]} /> If ventricular fibrillation recurs, drug treatment may be added to the ICD; during many episodes in quick succession (an "electrical storm") a medicine may be given into a vein; if the episodes are triggered by the same extra beat and medicines do not help, catheter ablation may be done.<Cite n={[1, 3]} /> In selected cases without cardiac arrest — a faint that looks like it was caused by an arrhythmia, together with other risk features — an ICD or drug treatment may be considered; the arrhythmia specialist decides.<Cite n={[1, 3]} />

</Patient>

<Student>

An ICD is not recommended in asymptomatic patients with an isolated pattern (ESC, III C).<Cite n={1} /> ICD implantation is recommended in patients with early repolarisation syndrome who have survived cardiac arrest (I B).<Cite n={1} /> For recurrent VF in patients with the syndrome, drug treatment in addition to an ICD should be considered (IIa B); the MSD Manual explains that when frequent ICD shocks need to be suppressed, a particular antiarrhythmic drug may be effective because it blocks the outward potassium current that may be increased in this syndrome; the choice of drug is for the arrhythmia specialist.<Cite n={[1, 3]} /> For electrical storm, an intravenous drug infusion should be considered (IIa B), and for recurrent VF episodes triggered by a similar premature ventricular complex that does not respond to medical treatment, ablation of that premature ventricular complex should be considered (IIa C).<Cite n={1} /> An ICD or drug treatment may be considered in individuals with the pattern and arrhythmic syncope plus additional risk features, and in asymptomatic individuals with a high-risk pattern and a family history of unexplained sudden death at a young age (IIb C).<Cite n={1} />

</Student>

## When to call an ambulance

Early repolarisation syndrome can show itself as ventricular tachycardia, ventricular fibrillation and cardiac arrest.<Cite n={3} /> The Russian Ministry of Health guideline advises calling an ambulance if an arrhythmia episode comes with dizziness, weakness, feeling faint, loss of consciousness or a fast heartbeat, and also for episodes of feeling faint or loss of consciousness.<Cite n={2} /> An ambulance is also called when an implanted cardioverter-defibrillator has delivered a shock.<Cite n={2} /> Call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK).

In cardiac arrest outside hospital, people nearby are recommended to start cardiopulmonary resuscitation straight away.<Cite n={1} /> How to recognise cardiac arrest and what to do step by step is in the article on [ventricular fibrillation](../ventricular-fibrillation/).

<Quiz />