What Is Atrial Fibrillation?
Atrial fibrillation, often referred to as "afib", is an irregular heartbeat, a rapid heartbeat, or a quivering of the upper chambers of the heart, called the atria. Atrial fibrillation is due to a malfunction in the heart's electrical system, and is the most common heart irregularity, or cardiac arrhythmia. For more detail about how the heart works and what happens to the heart when it is in atrial fibrillation, see About the Heart.
What Does Atrial Fibrillation Feel Like?
Different patients have different symptoms. Some patients describe afib as feeling like skipped heartbeats, followed by a thud and a speeding up or racing of the heart. Others describe it as an erratic heartbeat, strong heart palpitations, or simply a rapid heart rate. For still others, it feels like fluttering, butterflies, or even a flopping fish in the chest. Others have chest and throat pressure that mimics a heart attack, or constriction around the left bicep.
The first time, it's really scary, and you wonder, "Is this a heart attack?" It may leave you dizzy, faint, light-headed, anxious, breathless, weak, or just plain exhausted. After it stops, you may feel drained.
For some people, afib doesn't stop, and may continue on for hours, days, weeks, months, or even years.
For Mellanie True Hills, founder of StopAfib.org, the first afib incident started with a skipped heartbeat, followed by her heart racing. During one episode while she was out for a walk, within seconds her heart rate more than tripled on her heart rate monitor, reaching over 300 beats per minute. She always became so dizzy, nauseous, and lightheaded that she feared passing out with each episode.
Occasionally she is asked, "How can you tell when you have a rapid heart rate or skipped heartbeats?" Her answer usually is, "It's hard to miss when your heart literally feels as though it is going to leap out of your chest." Generally, afib is overt, but for some afib patients, the symptoms can be subtle.
Is Atrial Fibrillation Serious?
While atrial fibrillation may not sound serious, and is often considered to be a minor health issue, it can actually be quite risky and potentially even life threatening.
Since the blood doesn't properly move from the atria into the ventricles and then on to the rest of the body, it can starve the body of oxygen-rich blood, leaving you feeling weak, tired, or even incapacitated.
Even more serious is that the blood that remains in the atria can pool and create blood clots, which may get spawned to the rest of the body, causing a stroke. Stroke is not only the number three killer, it is the number one cause of permanent disability.
Afib can also overwork the heart, and over a long period of time can cause heart failure.
How Big a Problem is Atrial Fibrillation?
As we age, the incidence of atrial fibrillation increases. As Baby Boomers continue to age, we can expect to see the atrial fibrillation epidemic worsen. Today afib impacts more than 5.1 million people in the United States, with expectations of 15.9 million by 20501. These numbers, from the Mayo Clinic, only reflect those with atrial fibrillation confirmed by an electrocardiogram, and don't include many more with symptoms but who cannot be confirmed. There are possibly also many more who don't yet know they have it.
The increase in obesity and stress in our society can be expected to accelerate the incidence of atrial fibrillation as well.
To learn what happens when the heart is in atrial fibrillation, see About the Heart.