Why is my child's heart rhythm irregular?

Why is my child's heart rhythm irregular?

When a Provider describes a child's heart rhythm they may use words like "regular" or "irregular".  What they are trying to explain is if the beat of the heart is coming at a predictable rhythm or not.

You can think of "regular" as beating like a metronome in music.  There is same amount of time that passes between each beat, every time.  When a rhythm is described as "irregular" the time between each beat is different.  That means an "irregular" rhythm doesn't have a predictable beat.  

One of the most common reasons in childhood for an "irregular" rhythm is called sinus arrhythmia.

What is Sinus Arrhythmia?

While the name may sound scary beacuse of the arrhythmia, the word simply means "without rhythm" and it is a very normal finding in children.  

If you have ever felt their pulse, listened over their chest, or watched on a monitor you may have noticed that a child's heart beats seem to alternate between fast and slow.  You may 3-4 beats that are closer together followed by 3-4 beats that are further apart.  

What is happending is that your child's heart is simply making small adjustments in their heart rate depending on whether they are breathing in or breathing out.  This is why sometimes we call Sinus Arrhythmia instead Sinus Rhtyhm with Normal Respiratory Phase Variation on an EKG.  An EKG may be enough to verify this is what is being heard.

This is just one example of how a healthy heart and healthy lungs work together.  As we get older this interaction tends to become less obvious or even go away.  However in children and very fit individuals it is usually noticable and a normal finding.

When should we worry about an abnormal rhythm?

If your child has symptoms of palpitations, syncope (fainting), or problems during exercise you may want to have further evaluation.  An "irregular" rhythm can sometimes indicate Extra Beats (Ectopy) or an abnormal rhythm.  

We may recommend an EKG, Echocardiogram, Holter or Event monitor to further evaluate your child.