Ventricular Septal Defect (VSD)

What is a Ventricular Septal Defect?

A ventricular septal defect (or VSD for short) is a hole in the heart – specifically in the ventricular septum (the dividing wall between the right and left ventricles of the heart).

The ventricles are the lower pumping chambers of the heart.

A ventricular septal defect can be large or small, can happen on any part of the ventricular septum, and more than one can be present at one time.

In a normal heart, the pressure is naturally higher in the left hand side of the heart than the right. As a result, if your baby has a VSD, some oxygen-rich blood will pump into the right hand side of the heart, instead of flowing into the aorta. This means that the right ventricle has to work harder to pump the extra blood into the lungs and pulmonary artery. High blood pressure in the pulmonary artery is called Pulmonary Hypertension which can permanently damage the lungs if it isn’t treated.

At the same time, the left ventricle must work harder to compensate for the blood that moved into the right ventricle – ensuring that enough blood is reaching the rest of the body.

How can it be spotted?

The size of the VSD will affect the type of symptoms, the severity of symptoms, and the age at which they first occur.

Depending on the size of the ventricular septal defect, moderate to large VSD‘s can be detected during routine pregnancy scans. Our specialist fetal cardiac training helps sonographers to be better able to do this.

Babies with undetected large VSDs will usually begin to show symptoms within 4-8 weeks after birth. They will appear to be breathless and, because of the extra effort they are having to put into breathing, will not be interested in feeding. As a result, they will not be gaining weight as normal. They may also have frequent chest infections and appear to be always tired.

A VSD can often be picked up by listening to the heart – the noise of the extra blood flowing through the valve can be heard as a heart murmur.

To confirm the presence of a VSD, an echocardiogram (or echo) is usually conducted. This is an ultrasound scan of the heart – which can show the pattern of blood flow through the VSD, and determine how large the opening is, as well as much blood is passing through it.

How can it be treated?

Small VSDs often do not require treatment and will usually close naturally over a period of time.

Larger VSDs will need surgery to prevent permanent damage to the lungs and, ultimately, heart failure. The hole is closed using open heart surgery. There are various ways of doing this but the most common is to sew a piece of synthetic material over the hole. Your baby will be under general anaesthetic for the procedure, and, if all goes well, will only need to remain in hospital for a week or so after surgery.

For most babies, this procedure is low risk but it does depend on the general wellbeing of the child.

General advice/info for the future

Your cardiologist will advise you about any restrictions on activity that you should be aware of as your baby grows up, but they should be able to live a full and active life.

Your baby will have a scar down the middle of the chest, and there will be small scars where drain tubes were used, but these will fade over time.


Zareenah’s heart condition, pulmonary stenosis, was diagnosed at mum, Homaira’s 20 week scan. After she was born, doctors discovered Zareenah also had a VSD and an ASD. Read her story here: 

Pulmonary Stenosis: Zareenah's Story