It may feel like your heart skipped a beat, added a beat, is "fluttering," or is beating too fast (which doctors call tachycardia) or too slow (called bradycardia). Or, you might not notice anything, since some arrhythmias are "silent."
If you have an irregular heartbeat (called an arrhythmia), your doctor might suggest a treatment called cardioversion to help get your heart back into a normal rhythm.
If your heart beats too fast or unevenly, it can be dangerous. Your heart may not be pumping enough blood to meet your body's needs. An irregular heartbeat also can lead to a stroke or a heart attack.
Arrhythmias can be an emergency, or they may be harmless. If you feel something unusual happening with your heartbeat, call 911 so doctors can find out why it's happening and what you need to do about it.
Causes and Types of of Arrhythmias
You could have an arrhythmia even if your heart is healthy. Or it could happen because you have:
Premature atrial contractions. These are early extra beats that start in the heart's upper chambers, called the atria. They are harmless and generally don't need treatment.
Premature ventricular contractions (PVCs). These are among the most common arrhythmias. They're the "skipped heartbeat" we all occasionally feel. They can be related to stress or too much caffeine or nicotine. But sometimes, PVCs can be caused by heart disease or electrolyte imbalance. If you have a lot of PVCs, or symptoms linked to them, see a heart doctor (cardiologist).
Atrial fibrillation. This common irregular heart rhythm causes the upper chambers of the heart to contract abnormally.
Paroxysmal supraventricular tachycardia (PSVT). A rapid heart rate, usually with a regular rhythm, starting from above the heart's lower chambers, or ventricles. PSVT begins and ends suddenly.
Accessory pathway tachycardias. You can get a rapid heart rate because there is an extra pathway between the heart's upper and lower chambers. It's just like if there was an extra road on your way home as well as your usual route, so cars can move around faster. When that happens in your heart, it can cause a fast heart rhythm, which doctors call tachycardia. The impulses that control your heart rhythm travel around the heart very quickly, making it beat unusually fast.