Overview

What Is Arrhythmia?

Your heart beats approximately 100,000 times every day, delivering the blood your body need. Each heartbeat begins with an electrical impulse within your heart's own electrical network, which is called the conduction system. Consisting of a group of specialized cells within the wall of your heart, the conduction system controls the pumping action of your heart. Each electrical impulse starts in the atria, or upper chambers of the heart, and travels down to the ventricles, or lower chambers of the heart. This action produces a heartbeat.

In a normal heart, these electrical impulses occur at regular intervals. When something is wrong with your heart's conduction system, your heart does not beat regularly. The irregular beating results in a heart rhythm disorder, or arrhythmia.

Minor variations in your heart rate can be normal. However, extreme and prolonged changes in heart rate are abnormal and can cause symptoms. The normal heart rate is usually between 60 and 100 beats per minute.

Atrial fibrillation may be episodic or continuous and may or may not be recognized when it occurs. Symptoms depend on how fast the heart is beating and how much blood is being pumped to the rest of the body. Arrhythmias can range from harmless to life-threatening.