Palpitations and heart rhythm problems in children

The heart normally beats in a synchronised way, at regular intervals. Even then, heartbeat variations can occur, for example during exercise or sleep. While mostly harmless, some changes in heartbeat (known as heart palpitations) may indicate an underlying medical condition.

Here, Dr Martin Lowe, esteemed consultant adult and paediatric cardiologist, provides a detailed insight into palpitations and heart rhythm problems in children. He explains what are palpitations, what are the causes of palpitations in children, and when parents should seek medical attention for their child’s palpitations, among other important points.

Is it common for children to experience palpitations?

Palpitations, in many senses, are a normal thing. A heart palpitation is a feeling of having a stronger, irregular, fast or fluttering heartbeat, and can be similar to how the heart rate increases with exercise. With palpitations, an individual experiences an increasing awareness of the heart beating against the chest wall.

What is unusual, however, is to experience those symptoms at rest. For children who feel that their heartbeat is more prominent at rest, palpitations are an important symptom which may indicate an underlying heart rhythm disorder.

Palpitations can be a physiological (normal) response, because some young people have heart rates that are generally set a bit higher than average. As a result, they may be aware of their heart beating at rest, feeling as though they should be exercising, when in fact, they are not actually exercising. This can be normal, but any child who feels that their heart rate is excessively fast at rest and who is aware of palpitations at rest, should seek medical attention.

Why might my child have palpitations?

There are two main reasons for palpitations.

The first reason is that palpitations are representing a change in heart rhythm. This change may be a supraventricular tachycardia, which refers to an abnormal rhythm coming from the top chambers of the heart. Supraventricular tachycardias typically will present in childhood.

The second reason is that there may be an abnormality in blood pressure regulation. Often, the part of the nervous system that is responsible for controlling heart rate and blood pressure (called the autonomic nervous system) can become overactive in childhood, possibly leading to lower blood pressure than normal. As a consequence, the heart tries to compensate for that by beating faster, which might lead to an awareness of an increase in heart rate (palpitations). However, this can be in a completely normal heart rhythm; it is simply a faster heart rate than expected. This is quite a common cause of palpitations in childhood, particularly if children are going through a growth spurt or hormonal changes.

What serious medical conditions should my child be checked for if they have palpitations?

The main condition to be checked for is an abnormality of the heart itself, whether that is the heart muscle or the heart valves. This is because, sometimes, the first sign of something going wrong with how the heart is functioning is a change in heart rhythm, which can be felt as palpitations. Hence, one of the important investigations to look for that is an echocardiogram (an ultrasound of the heart) to look at both the heart muscle structure and the valve structure, making sure that the valves are not leaky or narrowed.

The other conditions to be checked for are those that affect the rhythm of the heart. There is one in particular, called Wolff Parkinson White Syndrome, that develops at birth and is thus, quite common in children.

Normally, the only way for the electrical impulse to get from the top chambers to the bottom chambers of the heart is through the junction box between the top and the bottom chambers, called the AV node. In Wolff Parkinson White Syndrome, there is an extra electrical connection that is able to bypass the normal electrical impulse. This can lead to a short circuit inside of the heart and a sudden change in heart rate and heart rhythm, with the heart beating in a rapid heart rhythm (perhaps at over 200 beats per minute). This is a potentially dangerous condition, because a rapid heartbeat can lead to a drop in blood pressure that results in collapse and, very occasionally, to a very dangerous heart rhythm that results in cardiac arrest. The latter is rare, but it is an important condition to pick up because it is readily treatable and curable with a technique called ablation.

Other children may also have a change in heart rhythm, but this is not due to Wolf Parkinson White Syndrome. Instead, it is usually because of an extra electrical connection in the heart or an irritable focus in the heart. These can be looked at and investigated further with an ECG echocardiogram recording and (where necessary) with an electrical study procedure, whereby catheters or electrodes are put inside of the heart itself via a keyhole technique, feeding them up from the vein at the top of the leg. This is an exploratory procedure that is performed as part of the overall ablation operation, when treatment is going to be recommended for these electrical abnormalities.

For definitive treatment, ablation offers cure in the vast majority of patients. It is also, certainly, more preferable in terms of treatment instead of lifelong medication, which used to be the treatment for heart rhythm problems before ablation was available.

When should I seek urgent medical attention for my child with palpitations?

Sometimes, it is not the child themselves that picks up or is aware of symptoms. Instead, it is the parent who, at times, notices their child’s heart beating against the chest wall and appearing to be excessively fast as a change in heart rate when their child is resting, inappropriate for the child’s resting state.

As a result, it is important to seek medical attention:

1. If a child feels that their heart beat is irregular, not beating in the normal way.
2. If a child complains of symptoms or is having unexplained symptoms, such as feeling dizzy or faint.
3. If a child feels that their heart rate is excessively high, particularly at rest.
4. If a parent notices something that is not quite right in their child’s heart rate, particularly at rest.
5. Certainly, if a child were to have an episode of collapse where they lose consciousness.

These would be the main symptoms leading to a referral.

Will my child's palpitations be lifelong?

Palpitations can be long-term, particularly if they relate to not a change in heart rhythm, but rather a normal heart rhythm yet elevated heart rate. An example of this is a heart rate that is perhaps higher than expected at times. A child with these symptoms may experience them for a long time, because they are not the result of an abnormality with the heart rhythm itself, but instead, how their heart as an individual works.

Palpitations that are due to a change in heart rhythm, on the other hand, are all treatable. Catheter ablation, which is the definitive treatment for heart rhythm issues, can be offered to any young person with a change in heart rhythm and it is highly effective.

If your child is experiencing recurrent palpitations, do not hesitate to visit Dr Lowe's Top Doctors profile today to receive the utmost cardiology treatment and care.