Your heart pumps blood that has been enriched with oxygen to the rest of your body. The typical heart has two upper chambers, called atria, and two lower chambers, called ventricles. During a normal heartbeat, your heart’s natural electrical system triggers each atrium to contract and push blood into the ventricles. Then, the ventricles contract, which propels the blood out of your heart to your body.
When this process is happening smoothly, you have a normal “sinus rhythm” in which your heart beats between 60 to 100 times per minute.
With atrial fibrillation, or Afib, the atria contract chaotically and unevenly, and are out of sync with the ventricles. As a result, the heart beats irregularly and often very rapidly. Your heart rate may increase to 180 beats per minute or higher.
An irregular heartbeat is called an arrhythmia. Afib is the most common type of arrhythmia. An estimated 3 million to 6 million Americans have Afib. That number is expected to balloon to 12.1 million by 2030 as the population ages.
Let’s observe National Atrial Fibrillation Awareness Month by learning about its symptoms, risk factors, causes and treatments.
Some people with Afib don’t notice any symptoms. Those who do may experience palpitations (sensations of a rapid, fluttering or thumping heartbeat), lightheadedness, extreme fatigue, shortness of breath, faintness or confusion, weakness, dizziness, or chest pain or pressure.
NOTE: Chest pain or pressure may be signs of a heart attack. Call 911 immediately.
Anyone can develop Afib, but some factors put you at a higher risk. These include being older (it’s more common in people age 60 and older); having high blood pressure; having a family history of Afib; drinking alcohol, especially binge drinking; being obese; and having certain health conditions, such as heart disease, thyroid problems, chronic kidney disease, diabetes, asthma, sleep apnea or electrolyte imbalances.
There is no single cause of Afib. In most cases, its development is associated with another medical condition, such as cardiomyopathy, congenital heart disease, coronary artery disease, heart failure, heart valve disease, high blood pressure, pulmonary hypertension or chronic lung disease. It can also develop following heart surgery or after an infection.
In about 10 percent of cases, no underlying heart or lung disease is present. In these instances, the Afib may be caused by excessive alcohol or caffeine intake, stress, certain medications, electrolyte imbalances or genetic factors. Sometimes, no cause can be determined.
To diagnose Afib, your doctor will first ask you about your symptoms and family history. The doctor will likely use certain tests to evaluate the electrical activity in your heart. These tests may include:
• Imaging exams: Your doctor may use x-rays, CT or MRI scans to get clear pictures of your heart and lungs to look for abnormalities.
• Electrocardiogram (EKG): This test records how fast your heart is beating and the timing of the electrical signals as they pass through it.
• Echocardiogram: This test uses sound waves (echoes) to make a video of your heart as it beats.
• Exercise stress test: This test takes EKG measurements while you walk on a treadmill or ride a stationary bike.
• Holter monitor: This is a special machine that you wear for a few days while you engage in your normal activities. The monitor records your heart’s electrical activity 24/7 and captures any occurrences of Afib that your doctor can evaluate.
Treatment for Afib generally begins with medications. Your doctor may prescribe an antiarrythmic drug, which helps return your heart to normal sinus rhythm or maintain normal sinus rhythm. Rate control medications prevent the ventricles from beating too fast, and anticoagulant medications reduce the risk of blood clot formation.
If medication fails to control your Afib, you may need a procedure to treat the abnormal heart rhythm. One is electrical cardioversion, which uses an electrical shock to “reset” your heartbeat.
Ablation is a procedure that uses small burns or freezes to create scar tissue that interferes with the irregular electrical signals in your heart.
If your Afib persists after treatment with medication and ablation, you may be a candidate for surgery, specifically the Maze procedure. During the Maze procedure, your doctor will make a series of incisions or lesions in your right and left atria to confine the electrical signals to defined pathways. This prevents the atria from beating chaotically and causing the symptoms of Afib.
Afib by itself isn’t life-threatening, but it can lead to serious complications, including stroke. Afib is associated with an approximately five-fold increased risk of ischemic stroke. It causes about one in seven strokes. The risk increases because during Afib blood flows through the heart at a slower pace, making it much more likely to clot. If a clot gets pumped out of the heart, it can travel to the brain and cause a stroke.
Don’t take a chance. If you experience symptoms of Afib, see your health care provider and get checked out.