---
title: Total anomalous pulmonary venous return
description: What total anomalous pulmonary venous return is, why a newborn with this defect depends on an opening between the atria to survive, how it is found, how surgery corrects it and when urgent help is needed.
type: disease
aliases:
  - TAPVR
  - TAPVC
  - Total anomalous pulmonary venous connection
  - Total anomalous pulmonary venous drainage
sources:
  - tier: guideline
    org: minzdrav-rf
    title: Тотальный аномальный дренаж легочных вен
    year: 2024
    url: https://cr.minzdrav.gov.ru/view-cr/34_3
  - 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: Total Anomalous Pulmonary Venous Return (TAPVR)
    year: 2023
    url: https://www.msdmanuals.com/professional/pediatrics/congenital-cardiovascular-anomalies/total-anomalous-pulmonary-venous-return-tapvr
  - tier: reference
    org: msd-manuals
    title: Total Anomalous Pulmonary Venous Return (TAPVR) (Consumer Version)
    year: 2025
    url: https://www.msdmanuals.com/home/children-s-health-issues/birth-defects-of-the-heart/total-anomalous-pulmonary-venous-return-tapvr
sources_checked: 2026-10-13
review: null
---

Total anomalous pulmonary venous return (TAPVR) is a congenital heart defect in which none of the <Structure id="pulmonary-veins">pulmonary veins</Structure> connects directly to the <Structure id="left-atrium">left atrium</Structure>.<Cite n={[1, 3]} /> Instead, all the blood from the lungs takes an abnormal route to the <Structure id="right-atrium">right atrium</Structure>.<Cite n={[1, 4]} />

This blood can reach the left side of the heart, and from there the rest of the body, only through an opening in the wall between the atria — a patent foramen ovale or an [atrial septal defect](../atrial-septal-defect/).<Cite n={[1, 3]} /> So a newborn's survival depends on whether there is such an opening and how large it is.<Cite n={1} /> The defect can be treated only with surgery; without it, according to the paediatric Russian Ministry of Health guideline, only 20% of babies born with TAPVR live to the age of one year.<Cite n={1} />

<Diagram name="total-anomalous-pulmonary-venous-return">
  <p slot="normal">
    Normally four pulmonary veins, two from each lung, carry oxygen-rich blood into the left
    atrium.<Cite n={1} /> Only oxygen-poor blood from the body arrives in the right
    atrium.<Cite n={4} />
  </p>
  <p slot="disease">
    The diagram shows one type of the defect, the supracardiac type, which is the most
    common.<Cite n={1} /> The pulmonary veins do not drain into the left atrium but join a common
    confluence behind the heart.<Cite n={[1, 3]} /> From there the blood rises through a vertical
    vein into the superior vena cava or one of its tributaries, such as the innominate vein, and
    reaches the right atrium.<Cite n={[1, 3]} /> There it mixes with oxygen-poor
    blood.<Cite n={4} /> The mixed blood reaches the left side of the heart only through the opening
    between the atria, from right to left.<Cite n={[1, 3]} /> The right atrium and right ventricle
    receive extra blood and become enlarged.<Cite n={[1, 4]} />
  </p>
</Diagram>

## Why it happens

<Patient>

The defect forms before birth: in the embryo, the pulmonary veins fail to connect to the back wall of the future left atrium.<Cite n={1} /> Why this happens is not fully understood.<Cite n={1} /> It is a rare defect: according to the paediatric Russian Ministry of Health guideline, it occurs in 0.5–1.1 per 10,000 live births.<Cite n={1} />

Usually the pulmonary veins join into a common vessel, the confluence, and this connects to veins that carry blood to the right atrium.<Cite n={[1, 3]} /> The types of the defect depend on where it drains:<Cite n={[1, 3]} />

- **supracardiac** — the confluence drains into the superior vena cava or its large tributaries;
- **cardiac** — into the coronary sinus or straight into the right atrium;
- **infracardiac** — the confluence runs down through the diaphragm and drains into the veins of the liver or the inferior vena cava;
- **mixed** — the veins drain into several places at once.

What matters most is whether this route is narrowed. If it is, blood backs up in the lungs and the pressure in them rises, so the lungs cannot work properly.<Cite n={[1, 4]} /> Narrowing can occur with any type of the defect and makes the outlook worse.<Cite n={1} />

</Patient>

<Student>

In all forms of TAPVR, pulmonary venous return joins systemic venous return and enters the right atrium; the viability of the fetus and newborn depends on the presence and size of the interatrial communication, through which a right-to-left shunt occurs.<Cite n={1} /> This is usually a patent foramen ovale, but it may be combined with a secundum or primum ASD.<Cite n={1} /> Typical morphological features are enlargement of the right ventricle and right atrium, dilatation of the pulmonary artery and small left heart chambers, depending on the size of the interatrial communication.<Cite n={1} />

The paediatric Russian Ministry of Health guideline uses the Darling classification: supracardiac form 44–49%, cardiac 16–21%, infracardiac 26–28%, mixed 5–9%.<Cite n={1} /> Obstruction of the confluence occurs in 45% of cases with the supracardiac form and in 20% of patients with the cardiac form, and its risk is highest with the infracardiac form (85%).<Cite n={1} /> The mixed form is often associated with other complex congenital heart defects and heterotaxy syndrome.<Cite n={1} />

Obstruction is accompanied by pulmonary venous hypertension, which increases as pulmonary vascular resistance naturally falls after birth.<Cite n={1} /> Without obstruction, pulmonary blood flow is increased, and [pulmonary hypertension](../pulmonary-hypertension/) develops because of the shunting of blood.<Cite n={1} /> TAPVR may be associated with other defects, such as [tetralogy of Fallot](../tetralogy-of-fallot/), single ventricle or heterotaxy syndrome.<Cite n={1} />

The share of TAPVR among all congenital heart defects is 0.4–0.9% according to the paediatric Russian Ministry of Health guideline<Cite n={1} />, and 1–2% according to MSD Manuals.<Cite n={3} />

</Student>

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

The 3D model shows a normal heart: highlighted are the pulmonary veins, which normally drain into the left atrium, both atria and the <Structure id="interatrial-septum">wall between them</Structure>.<Cite n={1} />

## Symptoms

<Patient>

If there is no narrowing, there are no symptoms at birth.<Cite n={1} /> Soon, half of the children develop breathlessness, a cough, feeding difficulties, frequent colds and signs of [heart failure](../heart-failure/), and the rest do so by the age of one year.<Cite n={1} /> The child breathes faster, develops swelling, and gains weight and grows poorly.<Cite n={1} /> The lips and nails may turn bluish (cyanosis); the blueness can appear at any age and is mild at first.<Cite n={1} /> Some children with the defect without narrowing may have no symptoms at all.<Cite n={[3, 4]} />

If the route of blood from the lungs is narrowed, the baby has difficulty breathing soon after birth, and the skin becomes noticeably blue.<Cite n={[3, 4]} /> This is a life-threatening condition: according to the paediatric Russian Ministry of Health guideline, without surgery children with this form of the defect die between 2 days and 4 months of age.<Cite n={1} />

</Patient>

<Student>

In the obstructive form, symptoms usually do not appear in the first 12 hours of life, which helps distinguish the defect from respiratory distress syndrome; this is followed by progressive dyspnoea, feeding difficulties and heart failure.<Cite n={1} /> Signs of right ventricular failure (hepatomegaly, peripheral oedema) appear in the first week of life in the obstructive form and at 3–7 weeks in the non-obstructive form.<Cite n={1} /> With infracardiac drainage, cyanosis and dyspnoea worsen with exertion and swallowing because of increased intra-abdominal pressure or compression of the confluence by the oesophagus.<Cite n={1} />

With obstruction, there is a parasternal heave, a single loud second heart sound and no significant murmur.<Cite n={3} /> Without obstruction, the second heart sound is split and does not vary with respiration, the pulmonary component is accentuated, and a soft systolic murmur is heard over the pulmonary artery.<Cite n={1} />

</Student>

## How it is diagnosed

<Patient>

The defect can be detected before birth: on a fetal ultrasound scan, as early as 18 weeks of pregnancy.<Cite n={1} /> After birth, doctors suspect it from a chest X-ray, a heart murmur or a low blood oxygen level on pulse oximetry.<Cite n={4} />

The diagnosis is confirmed by a heart ultrasound ([echocardiography](../../diagnostic/echocardiography/)).<Cite n={[1, 3, 4]} /> To see the anatomy more precisely before surgery, a contrast CT scan of the heart and vessels is done, sometimes an MRI.<Cite n={[1, 3]} /> An [ECG](../../diagnostic/ecg/) is also done.<Cite n={1} /> According to MSD Manuals, cardiac catheterisation is rarely needed.<Cite n={3} />

</Patient>

<Student>

Transthoracic echocardiography is recommended for all patients with suspected TAPVR (grade of recommendation B, level of evidence 3).<Cite n={1} /> In the supracardiac form, a dilated superior vena cava with accelerated turbulent flow is seen; turbulence, increased velocity and loss of phasic variability of flow indicate obstruction.<Cite n={1} /> CT angiography is recommended to clarify the anatomy when planning surgery (grade of recommendation C, level of evidence 5).<Cite n={1} />

On the chest X-ray, with drainage into the left innominate vein, a "figure-of-eight" shadow is seen<Cite n={1} />; MSD Manuals compares it to a "snowman".<Cite n={3} /> The ECG shows signs of right heart overload: tall peaked P waves, right ventricular hypertrophy, often in the form of incomplete right bundle branch block<Cite n={1} />, and right axis deviation.<Cite n={3} />

</Student>

## How it is treated

<Patient>

A diagnosis of TAPVR is in itself an indication for surgery.<Cite n={1} /> If the route of blood from the lungs is narrowed, the operation is done as an emergency, and a temporary improvement is no reason to delay it.<Cite n={[1, 3]} /> If there is no narrowing, the operation is done in the first 6 months of life.<Cite n={1} />

Before the operation, doctors support the child: they treat heart failure with medicines and, if the child is very unwell, put them on a ventilator.<Cite n={[1, 4]} /> If the opening between the atria is too small and urgent surgery is not possible, it can be widened with a special procedure, balloon atrial septostomy; in the most severe cases ECMO is used, a machine that adds oxygen to the blood.<Cite n={1} /> The doctor decides which of these measures are needed.

During the operation, the surgeon redirects the pulmonary veins into the left atrium: makes a wide connection between the confluence and the back wall of the left atrium, closes off the extra route to the body's veins and closes the opening between the atria with a patch.<Cite n={[1, 3]} /> The details of the operation depend on the type of the defect.<Cite n={1} />

Most children have good long-term results.<Cite n={1} /> But after surgery, narrowing where the veins join the left atrium, heart rhythm problems and residual pulmonary hypertension can occur.<Cite n={1} /> So the child is followed up by a cardiologist: at least once every 6 months after the operation, and after that as the doctor decides; in the first year, a heart ultrasound is done at least once every 3 months and an ECG at every visit.<Cite n={1} /> Some children need antibiotics before dental treatment and certain procedures to protect against endocarditis; the doctor decides whether this is needed.<Cite n={[1, 4]} />

The European guidelines classify adults with this defect, whether they have had surgery or not, as patients with a congenital heart defect of moderate complexity.<Cite n={2} />

</Patient>

<Student>

In anatomical repair, regardless of type, it is recommended to direct pulmonary venous return into the left atrium: create an unobstructed communication between the confluence and the left atrium, interrupt the connection of the confluence with the systemic veins and close the ASD (grade of recommendation C, level of evidence 5).<Cite n={1} /> Ligation of the vertical vein prevents a postoperative left-to-right shunt<Cite n={3} />; according to the Russian Ministry of Health guideline, the vertical vein is closed off if, on test clamping, left atrial pressure does not rise and arterial pressure does not fall.<Cite n={1} />

In the cardiac form, "unroofing" of the coronary sinus is recommended.<Cite n={[1, 3]} />

After repair, residual pulmonary hypertension, sick sinus syndrome, supraventricular tachycardias and residual obstruction of the pulmonary venous pathways occur.<Cite n={1} /> Postoperative pulmonary vein obstruction is the main cause of reoperation in TAPVR.<Cite n={1} /> The main risk factors for early and late mortality are pulmonary vein obstruction and associated cardiac anomalies.<Cite n={1} />

</Student>

## When to call an ambulance

The obstructive form of TAPVR is an indication for emergency hospital admission.<Cite n={1} /> If a newborn or infant is breathing fast and with difficulty, the skin or lips turn blue, or the baby cannot feed, call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK).<Cite n={[1, 3, 4]} />

After surgery, a sudden worsening of the child's condition, increasing breathlessness or an irregular heartbeat are also a reason to seek urgent help: if the child is very unwell, call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK).<Cite n={1} />

<Quiz />