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Atrial Fibrillation

Atrial fibrillation (AF or A-Fib) is the most common abnormal heart rhythm. It is a fast, complex, and chaotic rhythm of the upper chambers, or the atria. During AF, the typical rhythm is between 350 and 600 times per minute. At that rate, the upper chambers are not contracting normally. At first they quiver, but eventually there is mechanical standstill. The lower chamber, or the ventricles, also have an irregular and fast rhythm during AF. The AV node (aventricular node) acts as a filter, resulting in a ventricular rate between 100-200 beats per minute. 

Because the upper chambers are not contracting normally, the blood pools in these chambers and clots. The result of a dislodged clot is a stroke. The American Heart Association (AHA) estimates that of the 700,000 strokes occurring each year in the U.S., 15 percent -- about 105,000 -- occur in people with atrial fibrillation. Apart from the major side effect, it can result in symptoms causing a fair amount of morbidity. 

AF has traditionally been treated with antiarrhythmic medications in conjunction with blood thinners. The most common blood thinner prescribed is coumadin or warfarin. Electrical cardioversion is another technique frequently used to temporarily correct this problem.

Atrial Fibrillation Treatment at McLaren Port Huron

How is it treated?

  • Medications are used to slow down rapid heart rate associated with AF and other medications are used to thin the blood to reduce the formation of blood clots.
  • Electrical Cardioversion may be used to restore normal heart rhythm with an electric shock, when medication doesn't improve symptoms.
  • Cardiac ablation or Radiofrequency Ablation may be effective in some patients when medications do not work.