What Causes Atrial Fibrillation

“Why Me?” 

Just last week one of my patients was in the office asking this important question.  Carl was a man in his forties, balding, portly with a belly that hung at least a foot over his belt.  (I’ve changed his identity.)  Carl worked as a supervisor for a local trucking company.  Office work kept him extremely busy and stressed out, but he wasn’t all that physically active.

Carl had been sent to a cardiologist after being newly diagnosed with Atrial fibrillation.  He suffered from fatigue and annoying skipped heartbeats that made it extremely difficult for him to fall asleep at night.   

Indeed, a very common complaint of people with Atrial Fibrillation is that they feel distressed because of severe palpitations when they lay down at bedtime. 

Because Carl was fairly young and saw himself in relatively good health, he was wondering why he had been afflicted with this common heart rhythm problem. 

“Why me doc?”  he asked.  “I don’t smoke.  I don’t have any real heart disease that I know about.  Why should I have this heart rhythm problem?” Although Carl didn’t suffer from significant heart problems, he did have high blood pressure and in addition consumed a moderate amount of alcohol on a weekly basis.

The question of why someone gets Atrial Fibrillation (AF) is a very good one. 
In my last blog post, I began this discussion about Atrial Fibrillation, because it troubles so many people.  It is estimated that one out of every 140 people in America has Atrial Fibrillation. (ACC/AHA/ESC 2006 Guidelines for the Management of Patients With Atrial Fibrillation).

Atrial Fibrillation is an extremely costly medical problem.  It is estimated that over 15 billion dollars are spent every year on Atrial Fibrillation in the US. 

Atrial Fibrillation is an irregular heart rhythm that can lead to strokes for people who go untreated.  Because the upper chambers of the heart lose their natural organized pumping ability, blood can stagnate in these chambers much like eddies in a river where leaves and branches in the water coalesce. Stagnation in this way can cause the formation of blood clots. 

Sometimes the blood flow is so slow that the blood can actually be seen to be swirling.  Cardiologists call this “smoke.”  Strokes can happen when blood clots break loose and travel to the brain.

Carl’s question, “Why Me?”  is a good one because the treatment of Atrial Fibrillation is often based on understanding why this rhythm has occurred. 

Before I go any further let me give you some definitions of Atrial Fibrillation that may come up in the way your doctor decides to treat your condition. 

Atrial Fibrillation can be considered “paroxysmal” when it happens intermittently and stops on its own without treatment.  It can also be “recurrent” happening again and again with 2 or more episodes of Atrial Fibrillation.   If the Atrial Fibrillation lasts more than 7 days it is called “persistent.” The duration of AF refers both to individual episodes and to how long a person has been troubled by the rhythm problem.