Heart Rhythm (Arrhythmia)

An arrhythmia is an abnormal heart rhythm.

Some arrhythmias can cause problems with contractions of your heart chambers by:

• Not allowing the lower chambers (ventricles) to fill with enough blood, because an abnormal electrical signal is causing your heart to pump too fast or too slow.
• Not allowing enough blood to be pumped out to your body, because an abnormal electrical signal is causing your heart to pump too slowly or too irregularly.
• Not allowing the top chambers (atria) to work properly.

An arrhythmia can occur in the sinus node, the atria, or the atrioventricular node. These are called supraventricular arrhythmias. A ventricular arrhythmia is caused by an abnormal electrical focus within your ventricles. This results in abnormal conduction of electrical signals within your ventricles. Arrhythmias can also be listed as slow (bradyarrhythmia) or fast (tachyarrhythmia). “Brady-” means slow, and “tachy-” means fast.

In any of these situations, your body’s vital organs may not get enough blood to meet their needs.

What causes an arrhythmia?

An arrhythmia occurs when there is a problem with the electrical system that is supposed to control a steady heartbeat. With a problem in the electrical system, your heart may beat too fast, too slow, or irregularly.

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