Short Lesson on Arrhythmias

Arrhythmias are any abnormalities or disturbances in the normal rhythm of the heart. As a part of the circulatory system, the heart continuously pumps blood throughout the body, carrying oxygen and nutrients to all organs and tissues and also picking up waste products from the body’s cells. This muscular organ beats an average of 100,000 times a day or 60-100 beats per minute. When arrhythmias occur, the heart performs less efficiently which affects the entire body.

The heart pumps blood to the rest of the body in a regulated sequence of contractions within its four chambers. The two upper chambers are called the left atrium and right atrium. The lower chambers are the left ventricle and right ventricle. An electrical signal triggers the heart to beat (or contract and expand) and this action sends blood to the various chambers. The signal begins in the sino-atrial node located in the upper right atrium. The S.A. node is a natural pacemaker or electrical system that produces the signal that makes the heart beat. After the initial discharge of this signal, it travels to the lower chambers. Four valves each located in one of the four chambers, open and close to keep the blood flowing in one direction. This sequence of events is necessary for the heart to perform normally.

Arrhythmias can occur at any point along this sequence. A faulty pacemaker maybe the cause or the electrical discharge starts in an area other than the S.A. node. There are many reasons for this abnormality.

Arrhythmias can cause the heart to beat too fast or too slow. Under normal conditions, the heart may beat slower during sleep or beat faster during physical activity or emotional stress. The symptoms of both deviations are similar. A slow heart rhythm can be revealed in fatigue, lightheadedness, dizziness, or fainting. A too fast rhythm produces palpations, rapid heartbeat, dizziness, lightheadedness or fainting.

An examination by a doctor can determine the type of arrhythmia present. Performing a series of tests, including an EKG, can help make an initial diagnosis. There is also the Holter Monitor, a small battery operated devise that monitors the heart rate over a 24-hour period. The noninvasive procedure can be done in a hospital if severe arrhythmias are suspected. Usually, the device is worn as people go about their daily routine.

Treatment of arrhythmias, depending on the area of the heart where the disturbances occur, can be medication or an artificial pacemaker. These pacemakers can be temporary or permanent and are placed near the heart wall in a short invasive procedure. The artificial pacemaker is battery operated and gives an electrical signal to the heart to get it to beat in the normal progression of events.

Arrhythmias can be benign, life threatening or fatal, but with proper diagnosis, these disturbances can be counteracted to allow the heart to continue pumping at its normal and most effective rate.