---
title: Ebstein anomaly
description: What Ebstein anomaly is, how the displaced leaflets of the tricuspid valve change the work of the right heart, how the defect shows itself and is found, what approaches to treatment clinical guidelines describe, and when urgent help is needed.
type: disease
aliases:
  - Ebstein's anomaly
  - Ebstein malformation
sources:
  - tier: guideline
    org: minzdrav-rf
    title: Аномалия Эбштейна
    year: 2024
    doi: 10.24022/1810-0686-2025-22-2-127-154
    url: https://cr.minzdrav.gov.ru/view-cr/92_2
  - tier: guideline
    org: esc
    title: 2020 ESC Guidelines for the management of adult congenital heart disease
    year: 2020
    doi: 10.1093/eurheartj/ehaa554
    url: https://doi.org/10.1093/eurheartj/ehaa554
  - tier: reference
    org: msd-manuals
    title: Ebstein Anomaly
    year: 2023
    url: https://www.msdmanuals.com/professional/pediatrics/congenital-cardiovascular-anomalies/ebstein-anomaly
sources_checked: 2026-10-12
review: null
---

Ebstein anomaly is a congenital heart defect in which the leaflets of the <Structure id="tricuspid-valve">tricuspid valve</Structure> (the valve between the <Structure id="right-atrium">right atrium</Structure> and the <Structure id="right-ventricle">right ventricle</Structure>) are abnormally formed and displaced downwards, towards the apex of the right ventricle.<Cite n={[2, 3]} /> As a result, part of the right ventricle works as an atrium and the working part of the ventricle becomes smaller; the valve also often lets blood leak backwards.<Cite n={[2, 3]} />

It is a rare defect: according to the Russian Ministry of Health guideline, it accounts for 0.7 to 1% of all congenital heart defects, and both sexes are affected equally often; the guideline's authors note that these figures are somewhat out of date.<Cite n={1} /> Severity varies widely: from severe heart failure in newborns who need surgery soon, to valve changes found by chance on a heart ultrasound in older people.<Cite n={1} />

<Diagram name="ebstein-anomaly">
  <p slot="normal">
    Normally the leaflets of the tricuspid valve are attached to its ring (annulus), at the border
    between the right atrium and the right ventricle.<Cite n={[2, 3]} />
  </p>
  <p slot="disease">
    In Ebstein anomaly the anterior leaflet usually starts at the annulus but is enlarged and
    sail-like, while the septal and posterior leaflets are displaced towards the apex of the right
    ventricle and are often stuck to its wall.<Cite n={2} /> So between the annulus and the
    displaced valve there is an atrialised part of the right ventricle that works as an atrium,
    and the functional ventricle below the valve is smaller.<Cite n={[2, 3]} /> When the ventricle
    contracts, blood often flows back through the valve into the atrialised part and the right
    atrium, which then enlarge; the right atrium is drawn larger.<Cite n={[1, 2]} />
  </p>
</Diagram>

## Why it happens

<Patient>

It is a developmental defect: the heart forms abnormally before birth, and the defect is sometimes found on ultrasound during pregnancy.<Cite n={1} /> Cases in several members of one family have been described.<Cite n={1} /> The chance of the defect in a baby is much higher if the mother took lithium medicines in the first months of pregnancy.<Cite n={[1, 3]} />

Ebstein anomaly often comes with an opening between the atria — an [atrial septal defect](../atrial-septal-defect/) or a patent foramen ovale — and with extra electrical pathways, as in [WPW syndrome](../wpw-syndrome/).<Cite n={[1, 2, 3]} /> If the pressure in the right atrium becomes higher than in the left, some blood passes through this opening from right to left, and a bluish colour of the skin (cyanosis) appears.<Cite n={3} />

</Patient>

<Student>

Ebstein anomaly is a developmental defect of all the right heart structures: the right atrium (RA), the right ventricle (RV) and the tricuspid valve (TV); pulmonary valve disease and conduction pathway anomalies are possible.<Cite n={1} /> The primary abnormality is adherence of parts of the septal and posterior (inferior) TV leaflets to the RV endocardium: the effective valve orifice is displaced distally, the functional size of the RV is reduced, and an atrialised portion of the RV remains proximal to the orifice.<Cite n={3} />

An interatrial connection permits a left-to-right shunt or, especially during exercise, a right-to-left shunt; the anomaly may result in a chronically low systemic cardiac output.<Cite n={2} />

</Student>

<HeartModel highlight={['tricuspid-valve', 'right-atrium', 'right-ventricle']} />

## Symptoms

<Patient>

How the defect shows itself depends on age and severity. A newborn with a severe form may be markedly blue, a child mildly blue, a teenager may tolerate exercise poorly, and in an adult who has never had symptoms the defect may first show itself as attacks of a fast heartbeat.<Cite n={3} /> With a mild form a person may not know about the condition for decades.<Cite n={2} />

The main complaints are attacks of palpitations due to heart rhythm problems, breathlessness, tiredness, poor exercise tolerance, chest pain and a bluish colour of the skin.<Cite n={2} /> In most people breathlessness appears only during exercise.<Cite n={1} /> In a child, especially a baby, signs of the defect may include breathlessness, frequent respiratory infections, poor weight gain, sweating during feeds, refusing the breast and a fast heartbeat.<Cite n={1} />

Over time, with any form of the defect, [heart failure](../heart-failure/) can develop, and the risk of heart rhythm problems grows with age.<Cite n={1} />

</Patient>

<Student>

Key symptoms are arrhythmias (atrioventricular reentrant tachycardia, AVRT, is most common), dyspnoea, fatigue, poor exercise tolerance, chest pain, and peripheral and/or central cyanosis.<Cite n={2} /> According to the Russian Ministry of Health guideline, the prevalence of supraventricular tachycardias in Ebstein anomaly is 26–65%, and 10–45% of patients have right-sided accessory pathways, sometimes two or more.<Cite n={1} /> In patients with accessory pathways, atrial fibrillation (AF) or another supraventricular tachycardia with rapid conduction to the ventricles is potentially life-threatening because of the risk of degeneration into ventricular fibrillation.<Cite n={1} /> Multiple accessory pathways in conjunction with atrial tachycardia and AF are associated with sudden cardiac death (SCD).<Cite n={2} />

Typical complications include high-grade tricuspid regurgitation (TR), RV dysfunction and failure, liver cirrhosis, cerebral abscesses, paradoxical embolism, [pulmonary embolism](../pulmonary-embolism/), tachyarrhythmias, SCD and [infective endocarditis](../infective-endocarditis/).<Cite n={2} />

</Student>

## How it is diagnosed

<Patient>

When listening to the heart, the doctor may hear a widely split first heart sound — the "sail sound": the enlarged anterior leaflet closes later than usual; a murmur caused by blood leaking back through the valve is also often heard.<Cite n={[1, 3]} />

The main test is a [heart ultrasound (echocardiography)](../../diagnostic/echocardiography/). It confirms the diagnosis and helps to assess how severe the defect is and the outlook.<Cite n={1} /> The ultrasound shows how the leaflets are formed, how much blood leaks back through the valve, the size of the working and atrialised parts of the ventricle, and whether there are openings in the walls between the chambers.<Cite n={1} />

The [ECG](../../diagnostic/ecg/) in Ebstein anomaly is usually abnormal.<Cite n={3} /> If heart rhythm problems are suspected, [Holter monitoring](../../diagnostic/holter-monitoring/) is done.<Cite n={1} /> A chest X-ray shows an enlarged heart.<Cite n={[1, 3]} /> Cardiac MRI assesses the size and function of the right ventricle most accurately and helps to plan surgery.<Cite n={[1, 3]} />

</Patient>

<Student>

What distinguishes Ebstein anomaly from other TV anomalies is apical displacement of the septal leaflet of ≥ 8 mm/m² body surface area relative to the mitral annulus, measured on transthoracic echocardiography in the apical four-chamber view; the ESC gives the same threshold for adults (≥ 0.8 cm/m²) for the septal or posterior leaflet.<Cite n={[1, 2]} />

The ECG may show RA hypertrophy, a prolonged PR interval, right bundle branch block (often with a splintered QRS complex), deep Q waves in II, III, aVF and V1–V4, pre-excitation, low voltage, and supraventricular and ventricular arrhythmias.<Cite n={2} /> The P wave is usually tall and peaked (the "Himalayan" P wave).<Cite n={1} /> On the chest X-ray the cardiac silhouette has a typical globular or "inverted bowl" shape.<Cite n={1} /> MRI is the gold standard for assessing RV volume and function.<Cite n={1} /> An invasive electrophysiological study (EPS) is recommended for patients with arrhythmia symptoms and/or pre-excitation on the ECG.<Cite n={1} />

The Carpentier classification (1988) is based on the functional size of the RV and the state of the anterior TV leaflet, which matter for planning surgery: type A — anterior leaflet of normal morphology, RV size adequate; B — abnormal chordae of the anterior leaflet with preserved mobility, RV reduced but adequate; C — restricted mobility of the anterior leaflet, small RV with a large atrialised component; D — the leaflets form a fibrous "tricuspid sac" fused to the RV wall.<Cite n={1} />

</Student>

## How it is treated

<Patient>

Treatment is chosen according to the symptoms.<Cite n={2} /> Medicines, for example water tablets (diuretics) for swelling, relieve symptoms and help to prepare for surgery, but they do not remove the cause: the main way to treat and prevent heart failure with this defect is surgery.<Cite n={[1, 2]} /> Only the treating doctor decides which medicines are needed and when to change them.<Cite n={1} />

Surgery is recommended for severe regurgitation if there is heart failure, if tests show that exercise tolerance is getting worse, or if the right ventricle starts to contract less well.<Cite n={[1, 2]} /> With severe regurgitation, surgery is also considered without symptoms if the right side of the heart is gradually enlarging or right ventricular function is declining.<Cite n={1} />

Where possible, the valve is repaired rather than replaced with a prosthesis.<Cite n={[1, 2]} /> The modern method is the "cone reconstruction": the leaflets are shaped into a cone-shaped valve and attached to the true valve ring.<Cite n={[1, 3]} /> The opening between the atria is closed during the same operation.<Cite n={[1, 3]} /> The operation should be done by a surgeon with experience in exactly this kind of surgery.<Cite n={2} /> If the valve cannot be repaired, it is replaced with a prosthesis.<Cite n={1} /> Sometimes another operation is needed later.<Cite n={2} />

Attacks of tachycardia are preferably treated with catheter ablation.<Cite n={[1, 2]} /> If the ECG shows signs of pre-excitation, it is recommended soon.<Cite n={1} /> After valve surgery it can be harder to reach the right places with a catheter, so ablation is done before the operation where possible.<Cite n={[1, 2]} /> People who have had a paradoxical embolism or who have atrial fibrillation are recommended medicines that reduce blood clotting.<Cite n={[1, 2]} />

Follow-up by a cardiologist is needed for life, including after surgery; for adults, in centres that treat adults with congenital heart disease.<Cite n={[1, 2]} /> Dental and other procedures that break the skin or mucous membranes must be agreed with the cardiologist in advance.<Cite n={1} />

</Patient>

<Student>

There is no convincing evidence of benefit from ACE inhibitors, angiotensin II receptor blockers, beta-blockers or ivabradine in Ebstein anomaly; heart failure has an anatomical basis, so surgical correction of the defect is the main way to treat and prevent it.<Cite n={1} />

In the Russian Ministry of Health guideline, surgery for severe TR with heart failure, objectively reduced exercise tolerance or progressive RV systolic dysfunction is class I, level C, and surgery for progressive right heart dilatation or reduced RV function regardless of symptoms is class IIa, level C.<Cite n={1} /> TV repair is preferred over replacement; the modern technique is the cone reconstruction (da Silva, 2007): the leaflets are mobilised, the atrialised portion is plicated or resected, and a cone-shaped valve is created at the anatomically correct level.<Cite n={[1, 3]} /> An ASD or patent foramen ovale is closed at the same operation.<Cite n={[1, 2]} /> If the RV is too small for repair or marked RV dysfunction has developed, an additional bidirectional cavopulmonary (Glenn) anastomosis is created during the repair, provided LV function is preserved and left atrial pressure and LV end-diastolic pressure are not elevated.<Cite n={[1, 2]} /> In failed repair or severe biventricular dysfunction, heart transplantation may be the only option.<Cite n={2} /> In specialised centres operative mortality has fallen from more than 25% to less than 6%, and over 90% of patients operated on by an experienced surgeon survive more than 10 years.<Cite n={2} />

Radiofrequency ablation is first-line therapy and preferable to long-term drug therapy when there is a limited ablatable substrate; with pre-excitation on the ECG or EPS it is recommended soon (class I, level C, in the Russian guideline).<Cite n={1} /> Oral anticoagulation is recommended after paradoxical embolism or with a history of AF.<Cite n={[1, 2]} />

In neonates with severe cyanosis and inadequate pulmonary blood flow, the [ductus arteriosus](../patent-ductus-arteriosus/) is kept open with prostaglandins until pulmonary vascular resistance falls; some neonates with a very severe form need palliative surgery.<Cite n={3} /> Follow-up is at least yearly in specialised adult congenital heart disease centres.<Cite n={2} />

</Student>

## When to call an ambulance

A newborn with a severe form of the defect may be markedly blue or have an attack of fast heartbeat; such babies are admitted to hospital as an emergency straight after birth.<Cite n={[1, 3]} />

In people with accessory pathways, atrial fibrillation or another supraventricular tachycardia with rapid conduction to the ventricles can be life-threatening, because it can turn into ventricular fibrillation.<Cite n={1} /> An attack of supraventricular tachycardia that doctors cannot stop with antiarrhythmic drugs is a reason for emergency admission to hospital.<Cite n={1} /> When to call an ambulance during an attack of palpitations is explained in the article on [WPW syndrome](../wpw-syndrome/).

The Russian Ministry of Health guideline advises seeing a cardiologist as soon as possible, outside the usual schedule, if any of these appear or suddenly get worse: breathlessness, tiredness, a bluish colour of the skin, swelling, heart rhythm problems, fainting, or signs of nervous system damage — loss of vision, hearing or speech, numbness or weakness of an arm or leg, even if brief.<Cite n={1} /> If there are signs of a stroke (sudden weakness or numbness on one side of the body, difficulty speaking, a drooping face), call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK) straight away. As with any heart 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 />