Heart palpitations: The signals of arrhythmia
A cardiologist looks at what's normal and abnormal palpitations
Sensations that come from the heart can be scary. Though our hearts are constantly beating, we are seldom aware of it; and when we do become aware of it - it can cause a great deal of concern.
“Palpitations” is a word that we use when we become aware of the beating of our own hearts. Like many things in medicine, palpitations can be both normal and abnormal. Who of us cannot remember feeling our heart race after we have been scared or excited? This sensation is typically normal. Our bodies respond to emotional stimuli by secreting hormones and activating nerves that tell our hearts to beat faster and harder (perhaps to get ready to run away from danger).
However, palpitations are not always normal sensations. Palpitations can also be felt when we experience an “arrhythmia.” The heart’s beating is controlled by electricity. Typically, the electrical impulses start in a specific location in the top chambers of the heart (the “sinus node”) before traveling down specialized conduction pathways (like “wires”) to activate the rest of the heart. Most arrhythmias in children come from a short circuit in the wiring of the heart. Instead of the sinus node dictating how fast the heart beats, it is the characteristic of the circuit that dictates how fast the heart beats.
Palpitations occur frequently in kids. Older children and adolescents typically have no problem describing their symptoms (feeling that their heart is “racing”, or “beating out of their chests”). However, young children cannot often accurately describe what they are feeling. Some may say “my heart is beeping,” but others might indicate that their chest or heart is “hurting” or “feeling funny.” It is not uncommon for children to “feel their heart beat in their neck.” Babies, of course, cannot tell us anything about the way they are feeling. Frequently, all that we notice in babies with arrhythmias are actually signs of heart failure (which occurs after about 24-48 hours of arrhythmia), such as poor feeding, trouble breathing, lethargy or fussiness.
How can we know the difference between normal sensations and those of an arrhythmia? Here are a few tips:
1.Onset and termination: Because arrhythmias are “short circuits,” they tend to start and stop suddenly. Often patients can remember the exact moment when the sensation started and stopped. Palpitations that come from anxiety, fear, excitement, etc. tend to start and stop more gradually.
2.Heart “beating in the neck:” Many arrhythmias alter not only how fast the heart beats, but how it squeezes, making it less efficient. Instead of all of the blood traveling forwards, some may travel backwards to the blood vessels in the neck, causing this strange sensation.
3.Associated symptoms: Arrhythmias are frequently accompanied by symptoms such as chest pain, shortness of breath, and dizziness.
4.Signs of heart failure in babies: Poor feeding, trouble breathing, lethargy, or fussiness could indicate an arrhythmia in babies and should prompt parents to seek immediate medical attention.
However, even with these tips, the difference between normal sensations and those coming from arrhythmias can be difficult to tease out. The only way to know for sure is to monitor the electrical activity of the heart (using an “electrocardiogram” or “EKG”) during symptoms. There are now many types of devices that can aid diagnosis in this way, and your cardiologist may send you home with one.
The good news-arrhythmias in children are typically very treatable-either with medicines or with a procedure called an “ablation.” Either way, the goal is for the child can carry on with normal life … without a beeping heart.