An arrhythmia is a change in the rhythm of your heartbeat. When the heart beats too fast, it's called tachycardia. When it beats too slow, it's called bradycardia. An arrhythmia can also mean that your heart beats irregularly (skips a beat or has an extra beat).
Call your doctor if you have any of these symptoms, especially if you have heart disease or have had a heart attack.
At some time or another, most people have felt their heart race or skip a beat. These occasional changes can be brought on by strong emotions or exercise. They usually are not a cause for alarm. Arrhythmias that occur more often or cause other symptoms may be more serious and need to be discussed with your doctor.
In most people, arrhythmias are minor and are not dangerous. A small number of people, however, have arrhythmias that are dangerous and require treatment. Arrhythmias are also more serious if you have other heart problems. In general, arrhythmias that start in the lower chambers of the heart (called the ventricles) are more serious than those that start in the upper chambers (called the atria). Your doctor will talk with you about the type of arrhythmia you have and whether you need treatment.
The heart has 4 compartments, or chambers. The walls of the heart squeeze together (contract) to push blood through the chambers. The contractions are controlled by an electrical signal that begins in the heart's natural "pacemaker" (called the sinoatrial node). Nerve impulses and hormones in the blood influence the rate of the contractions. A problem in any of these can cause an arrhythmia.
Minor arrhythmias may be caused by excessive alcohol use, smoking, caffeine, stress or exercise. The most common cause of arrhythmias is heart disease, particularly coronary artery disease, abnormal heart valve function and heart failure. However, arrhythmias can occur for no known reason.
Your doctor will ask if you have any of the symptoms of arrhythmia. Your doctor may also do some tests. One of these tests is an electrocardiogram, also called ECG or EKG. During this test, your doctor will have you lie down so your heart can be monitored.
Your doctor may also ask you to walk on a treadmill while he or she monitors your heart, or may want to monitor your heart while you do your daily activities. One way to do this is to wear a machine, called a Holter monitor, that continuously records your heart's rhythms for 24 hours. If your doctor wants to monitor your heart for more than 24 hours, he or she might recommend an event-recorder, a machine that records samples of your heart's rhythms and can be worn for a couple of days or longer. Other tests, called electrophysiologic studies, may also give your doctor information about your heart.
Treatment depends on the type of arrhythmia you have. Some mild arrhythmias require no treatment. Other arrhythmias can be treated with medicines. If another health problem is causing the arrhythmia, treatment is aimed at taking care of that problem. In more serious cases, other treatments are available, such as the following:
Acute Management of Atrial Fibrillation: Part II. Prevention of Thromboembolic Complications by DE King, MD; LM Dickerson, PharmD; JL Sack, MD (American Family Physician July 15, 2002, http://www.aafp.org/afp/20020715/261.html)
Written by familydoctor.org editorial staff
Reviewed/Updated: 09/10
Created: 09/00