The heart scan
Fetal cardiology scans can be performed from 13–14 weeks of gestation in specialist centres. However, in most cases the fetal cardiology scan is performed between 18 and 23 weeks.
It is similar to the routine scans you have while you are pregnant, although in this scan the fetal cardiologist concentrates on your baby’s heart. We use ultrasound to take pictures of the heart, which allows us to see how it is developing and how the blood flows around it. In many cases this confirms that the heart has developed normally.
Fetal heart scanning can detect most structural abnormalities of cardiac function. It can also detect disturbances in the rhythm of the heart. However, some abnormalities may not be seen, or only become evident after birth.
What we cannot diagnose before birth:
- Patent ductus arteriosus (PDA) – a fetal blood vessel, present in all babies before birth, that does not close properly and allows blood to mix between the aorta and pulmonary artery
- Atrial septal defect (ASD) – sometimes referred to as a a "hole in the heart", this is when the wall between the atria (upper chambers of the heart) does not close completely. This is present in all babies before birth
After the scan
We will explain the results of the scan to you as soon as it is over. If we find a problem we will explain all the options available to you and whether your baby is likely to need medical or surgical treatment after birth.
One baby in every 10 who is found to have a heart condition will have problems with other organs or with genes that are responsible for the development of these organs (a genetic problem). If we think this may be the case with your baby, we will offer advice and counselling and, if appropriate, refer you to a specialist obstetrician for further scans or tests such as amniocentesis.
If you would like a second opinion regarding the heart condition we can arrange this.
In the case of a cardiac diagnosis you will be offered follow-up cardiac scans so we can monitor your baby’s heart condition.
The fetal cardiology consultant and clinical nurse specialist will maintain contact with your local obstetrician, GP and midwife, to provide information on your ongoing care and delivery plans. They will also receive a copy of your scan report.
We will discuss with you the best place for you to deliver your baby. This could be at your local hospital or it may be a maternity unit closer to Royal Brompton Hospital so your baby can be transferred here soon after birth.