Atrial Fibrillation (AFib)

Atrial Fibrillation (AFib) is the most commonly diagnosed arrhythmia (heart rhythm problem), affecting millions of Americans. It is characterized by fast and irregular heart rhythms caused by electrical abnormalities located in the pulmonary veins of the left atrium. Left untreated, AFib can lead to congestive heart failure and stroke.

In normal rhythm, the heartbeat starts in the atrium (the top part of the heart). When the atrium beats, the signal goes to the ventricle (bottom part of the heart) and the ventricle beats. Following this pattern, the heart beats top-to-bottom, top-to-bottom. In atrial fibrillation, the upper chambers go into a sustained chaotic rhythm causing three things to happen:

1. The Pulse Becomes Irregular
Irregularity is the hallmark of atrial fibrillation. In some people, the pulse may be too fast and medications can slow it down. In other people, the heart rate may be too slow and a pacemaker can speed it up.

2. The Heart Function Becomes Less Efficient
The contraction of the atrium helps the ventricles (main pumping chambers) work more efficiently and effectively. In Atrial Fibrillation, the heart functions less efficiently.

3. Blood Clots Form
When blood isn't getting pushed along briskly, it clots. If a clot forms and ends up going to the brain, that can cause a stroke. The risk of stroke can be estimated using specific criteria for each factor.

AFib is essential to detect, diagnose and treat as early as possible. However, AFib can be complex because individuals experience symptoms so differently. It can have multiple causes. For instance, thyroid abnormalities can cause AFib. It is also associated with congestive heart failure, structural heart disease, and heart valve problems.

Some people may not feel any symptoms, so their condition goes unnoticed until a physician detects it during a routine examination. Others may experience only minor symptoms, while some are sensitive to the slightest sensation. Symptoms commonly reported include shortness of breath, lightheadedness, irregular pulse, palpitations or chest discomfort, and fatigue.

Ask the Expert: Atrial Fibrillation

Stephen A. Gaeta, MD, PhD

Stephen A. Gaeta, MD, PhD

Learn about causes, symptoms and treatment options for AFib.

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According to HealthDay News, moderate drinking is often touted as heart-healthy, but a large new study finds that even one drink a day might raise the risk of an abnormal heart rhythm called atrial fibrillation.

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