Your heart never takes a break. Each day it beats about 100,000 times, pumping blood, with its life-giving oxygen and nutrients, throughout your body. In an average lifetime, we rely on this tireless organ to beat more than 2.5 billion times, so of course we get concerned when the beat appears irregular.

When a heart is in atrial fibrillation, it means the organ isn’t beating at its most efficient rate. There can be consequences to an irregular or rapid heartbeat: it means the blood isn’t flowing through the atria (two of the heart’s four chambers) as quickly as it needs to, making the blood more likely to clot.  If the blood clot travels to the brain, it can cause a stroke; in fact, A-fib increases a person’s risk of stroke by 500 percent.

Clots can also travel to other organs. But even without clots, A-fib can wear down the heart’s pumping ability over time and weaken it. Even though A-fib may not always pose an immediate danger, it’s important to recognize its symptoms and get a diagnosis and treatment.

When the Heart is A-flutter

Most people think of a racing or “fluttering” erratic heartbeat as the chief symptom of A-fib. Often, however, no symptoms are present at all, and a person can live with atrial fibrillation without ever suspecting they have the condition. Here are some other heart flutter facts:

  • Atrial flutter is closely related to atrial fibrillation. A person with A-flutter may feel the heart beating very fast but regularly.
  • Flutter is different from heart palpitations; with the latter condition, the person feels a sudden pounding, fluttering sensation or a racing heartbeat.
  • Yet a third, related condition usually affects older people and is known as sick sinus syndrome, in which the sinus node—the portion of the heart that regulates heart rhythm—stops working properly. Symptoms include both quickened and slower heartbeat. Most commonly, sick sinus syndrome is treated by inserting a pacemaker.
  • Skipped heartbeats aren’t quite what they appear to be. The heart doesn’t skip beats; it only feels that way when a beat occurs earlier than normal, followed by a pause that might feel more powerful than the previous beat. This is called premature atrial contraction (PAC) and isn’t really A-fib; it happens in healthy people from time to time. PACs often are brought on by caffeine, alcohol, stress and fatigue.

Vague symptoms can be serious, too.

As with many conditions, some of the most important symptoms of A-fib also resemble other disorders. Here are a few to know:

  • Syncope (pronounced, “syn-ko-pee”), or fainting, usually happens when a person’s blood pressure is too low (hypotension) and the brain isn’t getting enough oxygen. The most serious type of syncope is cardiovascular, and it always signals a need to see a doctor.
  • Lightheadedness, a decrease in blood pressure and confusion all can be related to A-fib and, consequently, too little oxygen reaching the brain.
  • Shortness of breath has many causes, including anxiety, obesity, and a host of heart-related illnesses. When shortness of breath occurs alongside other symptoms to be aware of, it might be a sign of A-fib.
  • Chest pain and sudden weakness are two primary symptoms of a heart attack, but they also can indicate a more ongoing (and treatable) condition, such as A-fib.

When To See a Doctor

It’s important to remember that atrial fibrillation might not be a chronic, or ongoing, condition. Some people experience A-fib only occasionally: symptoms last for a few minutes or hours, then stop for no apparent reason. This type of A-fib is called paroxysmal, but it calls for treatment nonetheless.

If you experience any symptoms of A-fib, or if your heart or chest simply “feels weird” in a way you can’t pinpoint, make an appointment to see your doctor. For chest pains, however, take action immediately and seek emergency medical attention to rule out the possibility that you’re having a heart attack.