---
title: Ventricular septal defect
description: What a ventricular septal defect is, why it strains the heart and lungs, how it is found and which treatment approaches clinical guidelines describe.
type: disease
aliases:
  - VSD
sources:
  - tier: guideline
    org: minzdrav-rf
    title: Дефект межжелудочковой перегородки
    year: 2024
    url: https://cr.minzdrav.gov.ru/view-cr/806_1
  - 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: statpearls
    title: Ventricular Septal Defect
    year: 2024
    url: https://www.ncbi.nlm.nih.gov/books/NBK470330/
sources_checked: 2026-10-12
review: null
---

A ventricular septal defect (VSD) is a congenital heart defect: there is a hole in the <Structure id="interventricular-septum">wall (septum) between the right and left ventricles</Structure>.<Cite n={1} /> It is the most common congenital heart defect.<Cite n={[1, 3]} />

<Diagram name="ventricular-septal-defect">
  <p slot="normal">Normally the wall between the ventricles is intact, and blood from the <Structure id="left-ventricle">left ventricle</Structure> does not pass into the right.<Cite n={1} /></p>
  <p slot="disease">With a VSD, blood flows through the hole from the left ventricle into the right. Because of this, the pulmonary artery, the <Structure id="left-atrium">left atrium</Structure> and the left ventricle are overloaded with extra blood volume and become enlarged.<Cite n={1} /></p>
  <p slot="treated">After the procedure the hole in the wall between the ventricles is closed: during surgery it is stitched or covered with a synthetic patch, and through a catheter it is closed with an occluder.<Cite n={[1, 2]} /> The doctor chooses the closure method. A residual shunt through the wall may remain after the defect is closed.<Cite n={[1, 2]} /></p>
</Diagram>

## Why it happens

<Patient>

A VSD is a congenital defect: the hole in the wall between the ventricles is already there at birth.<Cite n={1} /> Blood flows through it from the left ventricle into the right.<Cite n={1} /> As a result, the blood vessels of the lungs receive extra blood and the left ventricle is overloaded.<Cite n={1} />

If the overload lasts a long time, the pressure in the lung blood vessels rises.<Cite n={1} /> Small defects often close on their own.<Cite n={[1, 3]} />

</Patient>

<Student>

VSD accounts for 20–32% of congenital heart defects.<Cite n={1} /> The Russian Ministry of Health guideline classifies defects by location as perimembranous (bordered on one side by the central fibrous body), muscular (all margins muscular) and subarterial (the upper margin is formed by the semilunar valves); perimembranous and muscular defects are further divided into inlet, trabecular and outlet defects.<Cite n={1} />

Except in the end stage, VSD is characterised by a left-to-right shunt.<Cite n={1} /> The persistent shunt from the LV to the RV leads to pulmonary circulation overload (hypervolaemia) and LV volume overload; the pulmonary artery, left atrium and left ventricle are volume-overloaded, which leads to their dilatation.<Cite n={1} /> Long-standing volume overload of the pulmonary circulation increases pulmonary vascular resistance and raises pressure in the pulmonary artery and right ventricle, that is, it leads to pulmonary hypertension (PH).<Cite n={1} /> As the disease progresses, usually in adulthood, irreversible changes develop.<Cite n={1} /> Severe PH and a right-to-left shunt through the defect are features of Eisenmenger syndrome.<Cite n={[1, 3]} />

</Student>

<HeartModel highlight={['interventricular-septum']} />

## Symptoms

<Patient>

A child with a small defect usually feels well and has no symptoms.<Cite n={1} /> With a large defect, signs of heart failure appear: the child copes less well with activity, is breathless, has a fast heartbeat, often has chest infections and gains weight poorly.<Cite n={1} /> With a significant defect, heart failure often develops in early childhood.<Cite n={3} />

Most adults whose defect was repaired in childhood, and adults with a small unrepaired defect, usually have no symptoms.<Cite n={1} /> If the pressure in the lung blood vessels has become very high and Eisenmenger syndrome has developed, a bluish tint of the skin and lips, breathlessness, tiredness, coughing up blood and fainting appear.<Cite n={1} />

</Patient>

<Student>

Children with a restrictive VSD are usually asymptomatic; a non-restrictive defect causes signs of heart failure: delayed physical development, reduced exercise tolerance, dyspnoea, tachycardia and frequent bronchopulmonary disease.<Cite n={1} /> Eisenmenger syndrome is systemic-level pulmonary hypertension with a veno-arterial or bidirectional shunt; its clinical picture includes central cyanosis, dyspnoea, fatigue, haemoptysis and syncope.<Cite n={1} />

Auscultation reveals a moderate- or high-intensity (grade 3–5/6) holosystolic or early systolic murmur along the lower half of the left sternal border.<Cite n={[1, 3]} /> A systolic thrill is usually best felt at about the middle of the sternum.<Cite n={1} /> In small defects the murmur is harsh and loud, whereas in larger defects it tends to be softer and less intense.<Cite n={3} />

In patients with a subarterial VSD, a diastolic murmur of aortic regurgitation may be heard.<Cite n={1} /> In infundibular (supracristal) defects, aortic valve prolapse and regurgitation frequently develop.<Cite n={3} />

</Student>

## How it is diagnosed

<Patient>

The doctor listens to the heart: a murmur is usually heard with a VSD.<Cite n={[1, 3]} /> The key test is an ultrasound scan of the heart (echocardiogram) with Doppler.<Cite n={[1, 3]} /> An ECG and a chest X-ray are also done.<Cite n={1} /> If the ultrasound shows markedly raised pressure in the pulmonary artery, children over 6–12 months old with a large defect have a test of the heart chambers using a catheter to measure pressures and assess blood flow.<Cite n={1} />

</Patient>

<Student>

Echocardiography with colour Doppler is recommended for all patients; colour Doppler transthoracic echocardiography is the most valuable diagnostic tool for VSD.<Cite n={[1, 3]} /> The European guideline notes that in shunt lesions, including VSD, 3D echocardiography enables an en face view of the defect.<Cite n={2} />

An ECG is recommended for all patients to assess overload of the left and right heart, and a frontal chest X-ray to detect lung disease.<Cite n={1} /> Cardiac catheterisation is recommended in patients with a non-restrictive VSD older than 6–12 months when echocardiography shows markedly elevated pulmonary artery pressure, to assess PH and calculate haemodynamic parameters (shunt direction and size, PVR, pulmonary-to-systemic flow ratio); it is not used routinely to diagnose an isolated VSD.<Cite n={1} /> According to the ESC, in patients with shunt lesions and non-invasive signs of elevated pulmonary artery pressure, invasive measurement of pulmonary vascular resistance (PVR) is mandatory.<Cite n={2} />

</Student>

## How it is treated

<Patient>

If the defect is small, there are no symptoms and the pressure in the lung blood vessels is not raised, the outlook is usually excellent without any procedure.<Cite n={3} /> In babies with signs of heart failure, the doctor may prescribe treatment that eases its symptoms.<Cite n={1} />

Surgery is recommended, for example, when there are signs of heart failure or a significant shunt overloading the left side of the heart, as long as the changes in the lung blood vessels are still reversible.<Cite n={1} /> In babies in the first six months of life with a large defect, surgery is recommended if heart failure does not respond to medicines.<Cite n={1} /> During surgery the hole is stitched closed or covered with a patch of special material.<Cite n={1} /> In some patients the defect is closed with a catheter instead of surgery; whether this method is suitable depends on the type of defect.<Cite n={[1, 2]} /> If the pressure in the lung blood vessels has become very high and blood oxygen levels drop during exercise, closing the defect is not recommended.<Cite n={2} /> Whether to close the defect, and how, is decided by the doctor together with the patient or the parents.

</Patient>

<Student>

In infants in the first weeks and months of life with pulmonary hypervolaemia and heart failure, symptomatic therapy is recommended.<Cite n={1} /> Surgery is recommended in the presence of clinical symptoms of heart failure, a significant arteriovenous shunt and left heart overload on imaging, aortic valve prolapse, or a history of infective endocarditis, provided there is no irreversible pulmonary vascular disease.<Cite n={1} /> In infants in the first six months of life, primary repair is recommended for large (non-restrictive) defects with heart failure that does not respond to medical therapy.<Cite n={1} /> Surgical repair is also recommended separately for aortic valve prolapse with progressive aortic regurgitation.<Cite n={1} /> An isolated VSD is closed by direct suture or with a certified medical device (a synthetic patch or an occluder).<Cite n={1} />

The guidelines give PVR thresholds in different units. The Russian Ministry of Health guideline recommends surgical VSD closure in children with pulmonary hypertension when the PVR index is < 6 WU·m² and the PVR/SVR ratio is < 0.3.<Cite n={1} /> The ESC, when Qp:Qs > 1.5, gives defect closure class I with PVR < 3 WU, class IIa with 3–5 WU, and class IIb with PVR ≥ 5 WU (careful individual decision in expert centres).<Cite n={2} /> Desaturation on exercise is a contraindication to closure; shunt closure is not recommended in severe pulmonary arterial hypertension (PVR ≥ 5 WU) with desaturation on exercise.<Cite n={2} />

Transcatheter closure has become an alternative to surgery in selected patients, particularly in residual VSDs and in muscular defects located centrally in the septum.<Cite n={[2, 3]} /> When transcatheter closure is planned, the type of defect must be determined: muscular defects, perimembranous defects more than 4 mm from the aortic rim, and residual defects after repair are the most suitable.<Cite n={1} />

</Student>

## When to see a doctor

Take a child to a doctor if they are breathless or have a fast heartbeat, cope poorly with activity, gain weight poorly or often have chest infections.<Cite n={1} /> An adult with a VSD should see a cardiologist if they develop a bluish tint of the skin and lips, breathlessness, tiredness or coughing up blood: these can be signs of Eisenmenger syndrome.<Cite n={1} />

As with any heart condition, call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK) for fainting, chest pain or severe breathlessness: this is the site's general safety rule, repeated at the bottom of every page.

<Quiz />