Atrial Fibrillation
(Afib)
Causes
It’s estimated that about 2.7 million people in the U.S. are living with atrial fibrillation (Afib).1 While the root cause of Afib is the misfiring of electrical signals in the heart, which causes an irregular heartbeat, certain risk factors heighten the chance that Afib will occur.
Risk factors
Risk factors for Afib include the following:
- High blood pressure (hypertension) – Blood pressure is defined as the force with which blood presses against the artery walls as it circulates through the body. High blood pressure means the heart has to pump harder in order to circulate this blood. If you have Afib and high blood pressure, then you’re at a greater risk for stroke.
- Coronary artery disease (CAD) – CAD is a buildup of fat and cholesterol deposits, called plaque, in the arteries that supply blood to your heart. Plaque grows slowly, clogging the heart’s arteries. If a heart artery is severely blocked, it reduces blood flow to the heart and can cause chest pain or even a heart attack.
- Heart valve problems – Your heart’s valves are essential for proper circulation because they regulate the direction that your blood flows and play an important part in delivering necessary oxygen to your body. Heart valves that don’t work properly can put your heart and other organs at risk.
- Heart attack – A heart attack is the result of a sudden and complete blockage in an artery that supplies blood to your heart. CAD is the cause of these blockages in the arteries.
- Lung disease – While lung disease is one of the risk factors for Afib; it’s a general term for a number of medical problems relating to the lungs, including the following:
- Asthma
- Chronic obstructive pulmonary disease (COPD)
- Cystic fibrosis
- Pneumonia
- Tuberculosis (TB)
- Pulmonary edema
- Lung cancer
- Acute respiratory distress syndrome (ARDS)
- Pneumoconiosis
- Pulmonary hypertension
- Pulmonary embolism (PE)
- Stimulants – In general, anything that stimulates the heart to beat more rapidly can increase the risk of Afib. Alcohol, caffeine, certain medications (including over-the-counter cold medicines), and tobacco are all substances that can increase your heart rate and bring on episodes of arrhythmia. Illegal drugs such as amphetamines, methamphetamines, and cocaine (among others) may also produce Afib.
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Sleep apnea – Sleep apnea, which is caused by a temporary blockage of your breathing airway, is a risk factor for Afib. In fact, sleep apnea affects many people who have cardiovascular disease. If you have sleep apnea, your breathing may pause and restart several times while sleeping, which taxes the cardiovascular system. In addition to preventing you from getting restful sleep and contributing to exhaustion and difficulty concentrating during the day, sleep apnea can contribute to the misfiring of the electrical impulses in the heart and to episodes of Afib.
Sleep apnea is also very strongly linked to obesity (a body mass index, or BMI, >30), and if people are heavy snorers or their partner tells them they stop breathing at night or they find themselves falling asleep frequently during the day, they should ask their doctor about a sleep study, which can often be done at home now. - Cardiomyopathy – Cardiomyopathy is a general term that refers to diseases of the heart muscle. In cardiomyopathy, the heart becomes enlarged, thick, or tough, meaning it doesn’t beat as well and is less able to pump blood effectively, thus making it more prone to arrhythmias, including Afib.