Atrial Septal Defect (ASD)

Great Ormond Street Hospital for Children NHS Foundation Trust: Information for Families

Atrial septal defect (ASD)

This information sheet from Great Ormond Street Hospital explains the causes, symptoms and treatment of an atrial septal defect and where to get help.

The atrial septum is the wall of tissue and This type of heart problem can occur on muscle between the upper two chambers its own, but may also occur together with (atria) of the heart. An atrial septal defect other forms of congenital heart disease. (ASD) is a hole in this wall. There different types of atrial septal A hole or defect such as this allows both defect, depending on the location of the upper chambers of the heart (atria) to hole in the atrial wall: communicate and permits an abnormal Central defects of the atrial wall flow of blood from one chamber to the (secundum type defects) This is the most other. This means that the oxygen-rich and common type of ASD. All babies have the oxygen-poor blood, instead of being a small hole in the atrial septum while kept separate, are allowed to mix and flow in the womb, covered by a small flap from the heart to the body and lungs. called the foramen ovale. If the hole remains after birth, it is called a patent foramen ovale (PFO). Low defects of the atrial wall (primum ASD) This type of ASD occurs together with an abnormality of the one-way valve between the upper and lower left heart (the mitral valve). It can also be part of a more complex type of heart problem called an atrioventricular Atrial septal defect (AVSD). septal High defects of the atrial wall (sinus defect venosus ASD) This type of ASD is commonly seen together with an abnormal position of the right upper pulmonary vein (one of the blood vessels bringing oxygenated blood back to the heart).

Sheet 1 of 3 Ref: 2013F1103 © GOSH NHS Foundation Trust October 2013 What causes How is atrial septal atrial septal defect? defect diagnosed? Atrial septal defect is a congenital heart Your child will have an echocardiogram, defect (present when your child was born). a non-invasive, high frequency The exact cause of congenital heart defects ultrasound scan of the heart. It allows isn’t often clear. Most heart problems in doctors to the see the structure of the children are present from birth due to an atrial valve and assess any abnormal anomaly in the way the heart forms during blood flow through the heart, as well as the very early stages of pregnancy. the overall performance of the heart and circulatory system. The reasons for this may be due to a number of factors, such as genetics, They may also have an electrocardiogram environmental factors or infection. The (ECG). This measures electrical activity in the likelihood that a heart problem will heart to see how well it is working. Doctors have been caused directly by anything will look to see whether the right side of you have done during pregnancy or the heart has thickened and whether it is early life is very rare. working harder than it should be.

What are the signs How is atrial septal and symptoms of defect treated? atrial septal defect? The treatment your child needs will Children with an atrial septal defect (or depend on the severity of the defect. PFO) may only show mild symptoms of Small, central atrial defects can close having a heart condition, or may not have spontaneously after a few years, and your any symptoms at all. child may only require regular supervision Frequent chest infections can be a sign in an outpatient clinic. that the oxygenation process is not If the defect is slightly larger, and working efficiently due to extra blood surrounded by good margins of heart flow to the lungs. tissue, a key hole procedure known as Large defects can cause extra strain on the cardiac catheterisation can be used to heart causing the right-hand side of the close the hole. This is usually undertaken heart to dilate (stretch). Babies with large as a day-case procedure. defects may be breathless and struggle to Large central defects or other types of feed and gain weight. Older children may ASD may require open-heart surgery for show a reduced tolerance for exercise. repair. The type of operation depends The extra flow of blood to the lungs upon the position of the defect and any usually produces heart murmurs in associated tissue damage (lesions). children (an abnormal heart sound) that This type of child heart surgery is the can be detected on routine health checks. most straightforward type of operation This is a common reason for referral. that our surgeons perform.

Sheet 2 of 3 Ref: 2013F1103 © GOSH NHS Foundation Trust October 2013 What happens next? Further information The long-term outlook for central types and support of atrial septal defect (ASD) is very good, Our Cardiorespiratory Unit regularly refers regardless of whether they require cardiac to information published by the British catheterisation or heart surgery. Heart Foundation (BHF) and the Children’s Children with low defects of the atrial Heart Federation when explaining atrial wall (known as primum defects) will septal defect (ASD) to our patients and usually require regular check-ups as an their families. outpatient to monitor their progress. Download the BHF atrioventricular However, most children do not need septal defect factsheet (PDF) further surgery, and go on to lead normal Read about atrial septal defect on the healthy lives. Children’s Heart Federation website

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Compiled by the Web team in collaboration with the Child and Family Information Group

Great Ormond Street Hospital for Children NHS Foundation Trust Great Ormond Street London WC1N 3JH

www.gosh.nhs.uk