Atrial fibrillation, or AFib, is the most common type of irregular heartbeat. About 2.7 million Americans have it. AFib happens when the electrical activity of the heart isn’t working the way it’s supposed to. That causes the heart to quiver and beat in an unpredictable rhythm. AFib can cause the heart to work harder to pump blood through the body. That can lead to heart failure. Because blood doesn’t move through the heart the way it should, blood can pool and form a clot. That can raise your risk of a stroke.
Some AFib risk factors, such as high blood pressure and heart disease, may seem obvious. But other conditions may seem unlikely to affect your AFib risk. Among them are endocrine disorders. Those are conditions caused by unusually high or low levels of certain hormones.
The endocrine system is made up of glands and organs that produce and control hormones that affect everything from metabolism to mood. The effects of too much or too little of certain hormones can affect the heart in ways that increase the chances for AFib or other abnormal heart rhythms (arrhythmias).
What’s the AFib-Endocrine Connection?
There are dozens of endocrine disorders, but a few are considered especially strong risk factors for AFib. They include:
Diabetes. It’s the most common endocrine disorder in the U.S. Type 1 diabetes means the pancreas doesn’t produce enough of the hormone insulin to control blood glucose (sugar) levels in your blood. With type 2 diabetes, the body doesn’t respond to insulin the way it should, so the pancreas keeps producing more until it can no longer keep up with demand. The reasons diabetes is a risk factor for AFib aren’t completely understood. But, one theory suggests that poorly controlled glucose levels can scar the atria (the upper chambers of the heart), interfering with their electrical activity.
Thyroid disease. The thyroid gland releases a hormone that affects metabolism, heart rate, and many more functions. Both an overactive thyroid (hyperthyroidism) and an underactive thyroid (hypothyroidism) are linked to greater AFib risk. But, hyperthyroidism contributes to AFib more often. Unusually high levels of thyroid hormone in the blood can raise the heart rate and cause arrhythmias, such as AFib.
Adrenal gland disorders. The adrenal glands produce a few different hormones, including aldosterone, cortisol, and adrenaline. High or low levels of these hormones can negatively affect the heart. For example, too much aldosterone — the hormone that controls electrolytes such as sodium and potassium — can greatly raise the risk of AFib, as well as stroke and heart attack. Alcohol, tobacco, and caffeine in large amounts can cause the adrenal glands to produce too much adrenaline, which can also increase the risk of AFib.
What Should You Do if You Have Hormone Issues?
If you have been diagnosed with an endocrine disorder – or have changing hormone levels because of menopause or other reasons – talk with your doctor about how your heart may be affected. Endocrine disorders can increase the risk of other cardiovascular problems, not just AFib.
You may be advised to have electrocardiograms (ECGs) from time to time to check for arrhythmias. This is a test that records the electrical activity in your heart. Your doctor may also recommend having your cholesterol and blood pressure checked more often. You may want to add a cardiologist (heart doctor) to your health care team, even if your heart appears to be healthy at the moment.
Other AFib Risk Factors
Endocrine disorders aren’t the only factors that raise your odds for getting AFib. Some of these things you can control. Others you can’t. Major AFib risk factors include:
Age. AFib in children and young adults is rare. The risk of getting AFib increases as you get older.
Alcohol consumption. Drinking too much alcohol is associated with a higher risk of AFib. Even just one drink appears to raise the risk of AFib.
Family history. If you have a close relative – such as a parent or sibling – with AFib, you could get AFib at a younger age.
High blood pressure. Long-term, poorly controlled high blood pressure can cause changes in the structure of the atria, which can lead to AFib.
Other heart conditions. Valve disease and coronary heart disease, as well as recent heart surgery, can raise the risk of AFib.
If you have been diagnosed with any type of heart condition, be sure to talk with your doctor about your risk for AFib.
What Are the Symptoms of AFib?
AFib happens when the heart’s upper chambers (atria) stop beating in a steady, predictable rhythm in coordination with the lower chambers (ventricles).
But how do you know if you have AFib? In some cases, the symptoms may be so mild, you’re never aware. Your doctor may notice an unusual pattern of heartbeats when listening to your heart during a routine exam.
For many people, the feeling of a fluttering heart is hard to ignore. You may feel that your heart is beating faster than normal or that you have an irregular heartbeat. Other common symptoms can include:
- Lightheadedness – you feel faint or dizzy
- Shortness of breath
AFib can be present all the time or it may come and go. It can last anywhere from a few minutes to a few days. When you have AFib, then your heart goes back to normal rhythm, it’s called paroxysmal atrial fibrillation. If it lasts longer than 7 days, it’s called persistent AFib. In that type, your heart doesn’t go back to normal on its own, and requires treatment.
Treating AFib When You Have an Endocrine Disorder
It can often be challenging to treat any condition when you have other medical issues that require medications or other therapies. Generally, though, standard AFib treatments shouldn’t get in the way of managing an endocrine disorder.
The most appropriate AFib treatment depends on how serious the arrhythmia is, and on other factors, such as your age and overall health. Medications are often the first-line treatments. Commonly prescribed AFib medications include:
Anticoagulant medications to reduce the risk of blood clots. You may take:
Rate-control medications to keep the ventricles from beating too quickly. Those may include:
- Beta-blocker, such as:
- Calcium channel blockers, including:
- Digoxin, which slows down electrical currents going from the atria to the ventricle
Rhythm-control medications to help restore a healthy, normal rhythm. Some examples:
Another common AFib treatment is ablation. This procedure uses a catheter that can deliver energy to destroy the small amount of heart tissue that may be causing the arrhythmia. Ablation has been shown to be an effective treatment for people with diabetes and hyperthyroidism.
Electrical cardioversion is another common treatment. It delivers low-energy shocks from outside the chest to reset to a normal rhythm. Cardioversion is often only a temporary solution.
What’s the Prognosis for AFib?
Research suggests that, on average, AFib shortens life expectancy by about 2 years compared with individuals who don’t have AFib. Though AFib can lead to life-threatening consequences, such as stroke and heart failure, it can also be a manageable condition. With proper treatment and a heart-healthy lifestyle, you may be able to live a long and active life with AFib.