Understanding Atrial Fibrillation

Atrial fibrillation causes, diagnosis, treatment and prevention

/ Author:  / Reviewed by: Robert Carlson, M.D

"AFib" may sound like a little white lie, but it’s actually a serious medical condition. Atrial fibrillation, or AFib, is the most common type of heartbeat rhythm problem.

According to the Centers for Disease Control and Prevention (CDC), as many as 6.1 million US adults are currently living with AFib.

AFib occurs when the heart’s electrical system doesn’t send the correct signals to the upper two heart chambers. This can cause the chambers (called the atria) to fibrillate, or to contract very quickly and irregularly. Instead of pumping blood correctly, AFib allows blood to pool in the atria. This can cause clots that can lead to stroke or heart attack.

Sumeet Chhabra, MD, a cardiologist at The Heart Hospital Baylor Plano, told dailyRx News a little more about AFib.

"While most AFib patients are 70 or older, we actually can see AFib in all age populations," Dr. Chhabra said. "There’s also a rare form of AFib that many young people can get."

Causes and Risk Factors

A disruption in the heart’s electrical system is the primary cause of AFib.

Patients with high blood pressure, heart disease or heart failure are more likely to develop AFib, according to the National Heart, Lung, and Blood Institute (NHLBI). Obesity, excessive alcohol and caffeine use, hyperthyroidism, sleep apnea and high stress levels may also contribute to AFib risk. Genetic factors also may play a role in AFib.

According to a 2009 study published in the journal Gender Medicineafter age 75 (the average age for AFib onset), around 60 percent of all patients with AFib are women. Women also have a high risk of AFib-related stroke and are more likely to live with stroke-related disability than men.


The most common symptom of AFib is a feeling like the heart is skipping, fluttering or beating too hard inside the chest.

AFib patients may also feel short of breath, find it difficult to exercise or exert themselves, feel dizzy or faint or have chest pain. However, many patients with AFib don’t have any symptoms at all.


Stroke and heart attack are among the most serious AFib complications. When blood pools in the atria, clots can form and be carried to the brain or to the heart.

According to the NHLBI, the risk of stroke is five times greater for AFib patients than it is for the general population. Women are also at a higher risk of stroke from AFib than men, which is concerning because stroke is the fourth leading cause of death in women.

AFib can also cause heart failure (the heart can't pump enough blood to meet the body's needs). In AFib, the ventricles are beating too fast and can't completely fill with blood. This may mean they're not be able to pump enough blood to the lungs and rest of the body.


A doctor can diagnose AFib based on a patient's symptoms, a physical exam, lab tests or diagnostic procedures.

In patients without symptoms, AFib may show up when a doctor listens to the heart or during a routine electrocardiogram (EKG). An EKG shows the electrical pattern of the heart. Some patients may need to wear a portable EKG monitor for 24 hours or longer to confirm the diagnosis.

Other possible options include a stress test or an echocardiogram. A stress test is an exercise test done while wearing a heart monitor, which shows how a patient's heart reacts to exercise. Echocardiograms use sound waves to create a moving picture of the heart.


According to Dr. Chhabra, AFib patients without symptoms may not need treatment. Others may not tolerate treatment well, such as "patients who are very elderly, patients who are very sick and some patients who cannot tolerate powerful blood thinners."

For those who do need treatment, there are four main goals: to prevent clots from forming, to control the number of heart beats per minute, to restore a normal heart rhythm and to treat any other problems — such as heart failure, hyperthyroidism or diabetes.

"There are many different ways to treat atrial fibrillation from an electrophysiological standpoint," Dr. Chhabra said.

To prevent clots, doctors typically prescribe anticoagulants like warfarin (brand name Coumadin), heparin or aspirin. These medications don’t actually thin the blood, but instead slow down the clotting process.

For rhythm control, doctors may prescribe medications or perform a procedure called a cardioversion. In cardioversion, a low-energy electrical shock is applied to the heart to jolt it back into a normal rhythm.

Dr. Chhabra noted that a procedure called ablation is also another option.

"There are two main kinds of [heart] ablations we use for atrial fibrillation," Dr. Chhabra said. "One is traditional kind — the burning kind — where a small catheter delivers small localized energy [to the heart muscle] to fix spots. The other kind of ablation is cryoablation [which] delivers cooling to localized spots to freeze cells and cure abnormal circuits."


Patients may be able to prevent AFib by following a healthy diet, not smoking, limiting caffeine and alcohol intake, exercising regularly and maintaining a healthy weight.

According to Dr. Chhabra, treatment is very effective in most cases, but ongoing medical care is important.

Review Date: 
September 10, 2015