The Medical Minute: Atrial Fibrillation -- What is It?
Atrial fibrillation (AF) is the most common heart rhythm disturbance in the United States and affects 2 to 4 million Americans. It is usually a disease of aging, however it can affect people of all ages -- 1 percent of people under age 60 and 10 percent of all people over age 80 have AF.
In AF, the normal electrical impulses are disorganized and originate from the atria and pulmonary veins, resulting in a fast and irregular heartbeat. This irregular heart beat may last from minutes to weeks, or may even be continuously present. The natural tendency of AF is to become a chronic condition. Some patients are not aware of the arrhythmia, while others experience incapacitating symptoms like palpitations, shortness of breath, dizziness, syncope and chest pain. People with AF also have an increased risk of stroke.
Other factors, besides age, that put individuals at risk for developing AF are high blood pressure, obesity, hyperthyroidism, chronic obstructive pulmonary disease, diabetes and heart disease. Most people can tell there is something wrong when they have AF because it causes symptoms of heart fluttering or racing, shortness of breath, fatigue and light headedness. However, there are some people that cant feel it at all and dont know anything is wrong. It is important to recognize and treat AF early. Atrial fibrillation is responsible for 25 percent of all strokes -- thats about 70,000 strokes each year. Other causes of death related to AF are congestive heart failure and myocardial infarction.
Atrial fibrillation is usually diagnosed by an EKG, or electrical tracings of the heart beat. Often it is found by your family doctor when he listens to your heart. Once an individual has been diagnosed with this, they may be referred to an electrophysiologist, who specializes in the treatment of AF. Other testing that is usually done is a noninvasive ultrasound study (echocardiogram) to analyze the size and function of the heart chambers and the function of the cardiac valves. A stress test also may be performed to help decide which medications can be used to treat the AF.
Patients at increased risk of stroke should receive warfarin or new anticoagulants drugs such as dabigatran. Patients with heart disease, high blood pressure, diabetes and a history of stroke are at a high risk. Patients who are a low risk for stroke can be treated with aspirin. Atrial fibrillation is usually treated with medications that either slow the heart rate or convert the heart rhythm back to normal. Sometimes an electrical cardioversion or shock to the heart can be used to restore a normal heart rhythm. There are also procedures called ablations that may be used to prevent the recurrence of AF in certain individuals.