When a person suffers from atrial fibrillation, the upper chambers of his heart contract too quickly or at an irregular pace. The causes of atrial fibrillation usually include damage to the heart, either from a heart attack or high blood pressure. Heart defects, valve abnormalities, or a problem with the sinus node or pacemaker are other common causes of atrial fibrillation. A person can suffer from atrial fibrillation as a result of alcohol abuse or from using tobacco. In some cases, the causes of atrial fibrillation are unknown.
During a normal heartbeat, the sinus node sends a signal for the heart to pump blood. The signal tells the upper right chamber, or atrium, to pump blood into the left chamber and then down to the lower chambers, or ventricles. The ventricles then pump the blood into the lungs and through the rest of the body. This process usually happens 60 to 100 times a minute. In a person with atrial fibrillation, it can occur up to 175 times a minute.
Some sort of damage to the heart is a common cause of atrial fibrillation. A heart attack can lead to atrial fibrillation. People with heart failure or another form of heart disease can also suffer from atrial fibrillation. High blood pressure also increases a person's risk.
Other causes of atrial fibrillation include sick sinus syndrome. When someone has sick sinus syndrome, the sinus node doesn't function the way it should, disrupting the heart's rhythm. Although symptoms are not common, a person can feel tightness in his chest or shortness of breath. Usually, a person will have to have an artificial pacemaker installed to control the condition.
The causes of atrial fibrillation may not specifically relate to the heart. For instance, hyperthyroidism can cause atrial fibrillation, as can diabetes and sleep apnea. Stress can also lead to atrial fibrillation.
Binge drinking puts stress on the body and can disrupt the heart's rhythm. Depending on how sensitive a person is, even moderate alcohol intake can cause rhythm problems. Stimulants such as nicotine or caffeine can also disrupt the heart's rhythm.
Strain due to infections such as pneumonia or a virus can lead to atrial fibrillation as well. Recovering from surgery increases a person's risk of the condition. If a person undergoes steroid therapy for another condition, such as asthma, she may increase her risk of getting atrial fibrillation.
Someone can lower his risk of getting atrial fibrillation by reducing his intake of stimulants, including those found in some over-the-counter medications and in alcohol. Eating a healthy diet high in vegetables and fruits can also prevent atrial fibrillation. Controlling conditions such as diabetes and high blood pressure that can cause atrial fibrillation can also help to prevent it.