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). 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. Arrythmias that occur more often or cause symptoms (see the box below) may be more serious and need to be discussed with your doctor.
What are the symptom arrhythmias?
Call your doctor if you have any of these symptoms, especially if you have heart disease or have had a heart attack:
Palpitations or rapid thumping in your chest
Feeling tired or light-headed Passing out
Shortness of breath
The heart has 4 chambers. The walls of the heart 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). The rate of the contractions is influenced by nerve impulses and hormones in the blood. 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.
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.
Your doctor will ask if you have any of the symptoms listed in the box above. Your doctor may also do some tests. One of these tests is an electrocardiogram, also called ECG. 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 for you to wear a Holter monitor for 24 hours. If your doctor wants to monitor your heart for more than 24 hours, he or she might recommend an event-recorder, which you wear for a couple of days or longer. Other tests, called electrophysiologic studies, may also give your doctor information about your heart.
What are some of the types of arrhythmias?
Atrial fibrillation The heart beats too fast and irregularly. This type of arrhythmia requires treatment and can increase your risk of stroke.
Paroxysmal atrial tachycardia The heart has episodes when it beats fast, but regularly. This type of arrhythmia may be unpleasant but is usually not dangerous.
Ectopic beats The heart has an extra beat. Treatment usually is not needed unless you have several extra beats in a row and/or other problems with your heart (such as heart disease, congenital heart failure).
Ventricular tachycardia and ventricular fibrillation The heart beats too fast and may not pump enough blood. These types of arrhythmias are very dangerous and need immediate treatment.
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:
An artificial pacemaker
An electronic device placed under the skin on the chest. It helps the heart maintain a regular beat, especially when the heart beats too slowly. Cardiac defibrillation (very brief electric shock) Can be used to stop an abnormal rhythm and restore a normal one. Surgery
Can correct certain types of arrhythmias. For example, arrhythmias caused by coronary artery disease may be controlled by bypass surgery. When an arrhythmia is caused by a certain area of the heart, sometimes that part of the heart can be destroyed or removed.