A look of concern, maybe even fear flashed across the face of the young woman.  I had just told her mother, a spry woman of 73 years, that she had an abnormal cardiac arrhythmia called Atrial Fibrillation.  She and the daughter were in my office together inquiring why she felt fatigued all the time. 

“What does that mean, Atrial Fibrillation?”  the woman asked.  “It sounds serious.  Is this going to interfere with my mother’s independence?  She lives alone.”

The daughter’s question is a common one raised by both patients and family when they have been diagnosed with this most common cardiac rhythm problem, and of course hearing you have an abnormal heart rhythm naturally makes them afraid.

Atrial Fibrillation is the most common heart rhythm problem in adults.   One out of every 100 people (1%) over the age of 60 has Atrial Fibrillation.  In people over 69 years old, 5% have Atrial Fibrillation.  (Braunwald’s Textbook of Cardiology online).

Atrial Fibrillation is an irregular heart rhythm that produces feelings of a jumpy pulse, palpitations, shortness of breath, and even a sensation of anxiety.  Many people are first aware that they have Atrial Fibrillation because of feelings of fatigue.  They feel “pooped out” all the time and wonder why?

My patient above came in with just this complaint.  She had been feeling exhausted all the time.  Her family wondered if she might be anemic or were afraid she might have cancer.

In fact, she had the typical presentation of Atrial Fibrillation, racing of the pulse.  Normally, our heart beat averages 50-80 beats a minute.  In Atrial Fibrillation it can race up to 160 or 180 times a minute.

A rapid chaotic beating of the upper chambers of the heart causes Atrial Fibrillation.  Our hearts have 4 chambers.  Two lower main pumping chambers called the Left and Right Ventricles, and two upper chambers called the Left and Right Atriums.  These upper chambers are “priming” chambers.  Much like a fuel injector system of a car, they usually work in sync with the lower chambers to make a more effective pumping of blood to the body.

In Atrial Fibrillation this natural sync is lost and in many patients the effective pumping of the heart is reduced by up to 25%.    In Atrial Fibrillation electrical activity in the upper chambers is very fast, 350-600 times a minute.

Luckily our hearts don’t beat this fast. A natural protective action occurs at the AV Node (an electrical center that acts much like a junction box) that slows the pulse down to a more manageable rate of 120-180 a minute.

Yet even this rate can be troublesome for some people.

Should you be worried if you have Atrial Fibrillation?

Atrial Fibrillation itself is rarely fatal, but serious side effects can occur.  Due to the lack of a well-organized heartbeat in the upper chambers, blood can stagnate and blood clots can form inside a pouch off the Atria called the Left Atrial Appendage.