Jefferson University Hospitals

Frequently Asked Questions

What is atrial fibrillation?

Atrial fibrillation (AF) is the most common abnormality of heart rhythm, affecting more than two million Americans. In a normal rhythm, the heart beats between 60 and 100 times per minute; in AF, the upper chamber of the heart beats rapidly and irregularly, which can lead to an increased heart rate.

Who has AF?

AF is relatively rare in young, healthy people, although it can occur. It is found most often in people over age 65 and in those who have heart disease. AF's prevalence increases as the population ages; approximately 10 percent of patients over the age of 70 will develop it.

What does AF have to do with stroke?

In AF, the irregular contractions of the left atrium may cause blood to pool, which may result in the formation of blood clots. These clots can break loose and travel through the bloodstream to the brain, causing a stroke.

Clinical risk factors for stroke in patients with AF include advanced age, history of a previous stroke or transient ischemic attack (temporary paralysis, numbness, speech difficulty or other neurologic symptoms that start suddenly but from which the patient recovers within 24 hours), heart failure, diabetes and high blood pressure.

Patients who are under the age of 65 and have none of the other aforementioned risk factors are at low risk for stroke.

How can you tell if you have AF?

AF often has no strong outward symptoms. Some people with AF will experience heart palpitations - often described as a “pounding,” “racing” or “fluttering” heartbeat. In other people, the only symptom of AF may be dizziness, faintness or light-headedness. Others may experience chest pain ranging from mild to severe. And for some, AF has no symptoms at all.

The only way to know for sure if you have AF is to have your doctor perform a painless test called an electrocardiogram (ECG). During an ECG, sensitive electrodes are placed on your chest. These electrodes pick up the electrical impulses generated by your body that cause your heart to beat. The impulses are then transmitted to a device that records them on a piece of paper called an ECG strip. By examining the specific pattern of electrical impulses recorded on the ECG strip, your doctor can tell for certain whether you have AF.

What can I do if I have AF?

Doctors have several options for managing AF. Whenever possible, the first treatment efforts will be directed at cardioversion - restoring your heart's normal rhythm. This can be done either through the use of electrical stimulation (direct-current or DC cardioversion) or through pharmacologic (drug-based) therapy. For many people, one or the other of these measures will work to convert the heart to normal rhythm. Patients with recurrent AF may require long-term treatment with medication.

Those who fail drug therapy may be candidates for a procedure called radiofrequency (RF) catheter ablation. During this procedure, physicians insert small catheters into the heart and apply RF current to target or ablate areas that may trigger or sustain AF.

AF treatment also concentrates on protecting you from blood clots that may lead to stroke. Your doctor may prescribe a medication called an "anticoagulant" to prevent clots from forming or growing. Warfarin (brand-name Coumadin®) is the drug of choice for long-term anticoagulation in AF patients. Controlled trials of anticoagulation have demonstrated that warfarin significantly reduces the risk of stroke in patients with AF and clinical risk factors. Although bleeding is more common in patients treated with warfarin, careful monitoring by physicians minimizes the risk of bleeding.

If your doctor has prescribed AF medication for you, it's important to take your medication exactly as directed. Failure to take your AF medication properly can significantly increase your risk of stroke or bleeding.

For an appointment with a Jefferson physician, please call 1-800-JEFF-NOW (1-800-533-3669) or visit our Web site at

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