Atrial Fibrillation (AFib): Causes, Symptoms and Treatment

Atrial fibrillation, known as AFib or AF, is one of the most common arrhythmias, problems with the rate or rhythm of the heartbeat. In AFib the heart beats irregularly and sometimes much faster than normal, and its upper and lower chambers do not work together as they should. The lower chambers then do not fill completely or pump enough blood to the lungs and body, which can cause dizziness, fatigue and a pounding heartbeat. AFib may come in brief episodes or be permanent. Treating it is very important, because it raises the risk of stroke and other heart problems.

Causes

AFib is most often caused by changes in the heart's tissue or in the electrical signals that drive the heartbeat. These changes can come from high blood pressure, coronary artery disease, congenital heart defects, infections and aging. Sometimes the cause is unknown.

Who is at higher risk

• Age, especially over 65
• Family history and genetics: AFib, and heart disease that raises its risk, can run in families
• Lifestyle: heavy drinking, smoking, and illegal drugs such as cocaine and methamphetamines
• Health conditions: high blood pressure, diabetes, heart failure, heart valve disease, obesity, hyperthyroidism, chronic kidney disease, COPD and other lung diseases, and sleep apnea
• Ancestry: AFib is more common in people of European descent
• Recent surgery on the heart, lungs or esophagus, in the following days and weeks

Symptoms

Some people have no symptoms and do not know they have AFib. Others notice symptoms occasionally, frequently, or severely; heart disease makes symptoms more likely and can make them worse. Symptoms can include:

• extreme fatigue, the most common symptom
• palpitations: a feeling that the heart is skipping, fluttering, pounding, or beating too hard or fast
• trouble breathing, especially lying down or exercising
• chest pain
• dizziness or fainting
• low blood pressure

Complications

Untreated, AFib can lead to stroke, heart failure, blood clots, sudden cardiac arrest, and cognitive impairment and dementia. Contact a provider about symptoms; the sooner AFib is diagnosed and treated, the better.

Diagnosis

A provider will ask about symptoms, lifestyle, other conditions and family history, examine you, and may order blood tests. Heart tests such as an electrocardiogram (EKG or ECG) and echocardiogram are likely, and you may be asked to wear a monitor that records the heart's electrical activity.

Treatment

• Medicines: blood thinners to prevent clots, and medicines to control heart rate and rhythm
• Heart-healthy habits: an eating plan that limits saturated fat, salt and cholesterol, such as the DASH plan; limiting or avoiding alcohol, which can raise heart rate; a healthy weight; regular activity; managing stress; and quitting smoking
• Procedures: electrical cardioversion, which uses low-energy shocks to restore normal rhythm, and catheter ablation, which scars the tissue causing the arrhythmia so the scar blocks the abnormal signals
• Surgery: a pacemaker to help control the rhythm; a Maze procedure, which creates a maze-like pattern of scar tissue in parts of the heart; or left atrial appendage closure, surgery on a small sac in the wall of the left atrium that helps prevent clots and reduce stroke risk, for people who cannot take blood thinners

Prevention

You can lower your risk by following heart-healthy habits, avoiding illegal drugs such as cocaine and methamphetamines, treating conditions that raise the risk, and, before heart surgery, taking antiarrhythmic medicine if advised.

Sources

• MedlinePlus (National Library of Medicine), "Atrial Fibrillation," from the National Heart, Lung, and Blood Institute. https://medlineplus.gov/atrialfibrillation.html