Premature Atrial and Ventricular Contractions
The heart has its own electrical system that organizes the activity of the four pumping chambers. The sinus node is the natural pacemaker of the heart and usually sends signals at regular intervals to the rest of the conduction system.
Sometimes, other areas of the heart can send signals that can activate the electrical system earlier than the sinus node. These are referred to as premature or early beats.
Early beats that start in the atrium or upper chambers of the heart are usually called premature atrial contractions (PACs) or atrial premature beats.
Sometimes these early beats can come from the ventricles or lower chambers of the heart. These are called premature ventricular contractions or ventricular premature beats.
People with normal hearts can have these early beats often and not realize they are having them, while others are very aware of every extra beat of their heart.
Sometimes things that speed up your heart rate, like caffeine or stress, can make these premature beats occur more often.
Description of Heart Palpitations
In addition to single extra beats, runs of fast rhythms, or tachycardias, can be sensed as palpitations.
Some children, particularly young adults, are aware of rapid heartbeats that are due to the speeding up of the heart that naturally occurs in response to exercise or stress. This is called sinus tachycardia and is normal.
Some children have extra connections of the heart's electrical system that can lead to tachycardia in an abnormal fashion.
What happens if my child has palpitations?
Premature beats are typically not dangerous and are very common. There are some situations when these extra beats require further review.
If these beats are linked with other symptoms, particularly fainting, further study is typically recommended.
Diagnosis of Heart Palpitations
A good history and physical examination are helpful in finding the cause of the palpitations.
If the child has fainting along with the racing of the heart, this may indicate a more dangerous heart rhythm problem and should be evaluated by a physician right away.
Most children with palpitations will have a normal cardiac exam. If their exam is not normal, the patient may have a structural problem with the heart that may be causing the palpitations (i.e., hypertrophic cardiomyopathy).
The physical exam may also give clues as to the function of the heart, which may be strongly linked with the palpitations.
To diagnose the problem, documentation of the heart rhythm while the patient is having the palpitations will be required. An electrocardiogram done during an office visit may not show the rhythm disturbance but will help to rule out any structural reason for the problem.
Portable monitors that record the heart rhythm outside of the hospital (Holter monitor) are usually the most helpful to diagnose the rhythm.
If the symptoms occur during exercise, an exercise test may be helpful in making the diagnoses.
Treatment for Heart Palpitations
Premature atrial and ventricular contractions do not typically need any therapy except staying away from things that make it worse, like caffeine. If they happen so often that they disturb normal daily living, there are some medications or procedures that can be used to try to control them.
There are several medicine and non-medicine treatments for the other causes of palpitations. The key is to make the diagnosis, or at least to rule out any life-threatening rhythms.
If a child has palpitations in association with fainting, this should be evaluated promptly.