An extrasystole is a type of irregular heartbeat pattern. It occurs when the lower chambers of the heart called the ventricles contract sooner than they are supposed to in a normal heart rhythm. The premature contraction is followed by a short pause and then a fast beat of the rest of the heart. Minor extrasystoles are fairly common and usually do not cause symptoms, though a very pronounced extrasystole can lead to palpitations, chest pains, trouble breathing, and other dangerous symptoms. Treatment typically consists of taking daily medications to regulate heart activity and control other underlying conditions.
A heartbeat cycle is usually triggered by an electrical signal from the sinoatrial node, located in the right ventricle. In the case of an extrasystole, cells in the ventricles emit their own electrical signals to begin a beat, while the sinoatrial node remains silent. Many different factors can contribute to electrical abnormalities in the heart, including congenital defects, heart disease, thyroid disorders, trauma, and extreme stress. People may be at an increased risk if they smoke, drink alcohol, and use stimulant drugs such as cocaine and methamphetamine. In some cases, no underlying causes or risk factors can be detected.
Symptoms of extrasystole may be related to the heartbeat problem itself or more closely tied to the underlying cause. In most cases, people do not notice changes in the way their hearts beat. Some patients do feel as if their hearts are skipping beats or going too slow. Other symptoms may include sharp pains in the chest, hyperventilating, lightheadedness, fatigue, and possibly fainting.
Doctors run a series of diagnostic tests whenever an extrasystole is suspected. A physical exam may allow the physician to hear and feel the abnormal heartbeat. Blood tests are important in checking for the presence of high cholesterol, infection, toxins, and chemical imbalances. An electrocardiogram, a test of electrical activity in the heart, is perhaps the most important diagnostic tool. It allows doctors to see exactly how and where abnormal contractions are occurring and how threatening they appear to be.
A patient who experiences severe symptoms may need to be hospitalized to receive oxygen and intravenous medications. Drugs called antiarrhythmics are often administered to stabilize electrical activity in the sinoatrial node and block signals from the ventricles. Once patients are stable, they are usually prescribed medications to take daily at home and instructed to make important lifestyle changes. Getting regular exercise, eating smart, and avoiding drugs and tobacco are essential for long-term heart health following an extrasystole scare.