Atrial Fibrillation

Atrial fibrillation is the most common abnormal heart rhythm. Normally the heart contracts and relaxes to a regular beat. The sinus node, located in the upper chamber (atria), is the heart's normal pacemaker. It sends electrical signals to the rest of the heart through the conduction system, which consists of the AV node, Bundle of His, bundle branches and Purkinje fibers.

In atrial fibrillation, the sinus node does not start the electrical signal. Erratic signals come in an erratic fashion from the atrial muscle instead. The heart normally beats between 60-80 times a minute at rest. Because the heart is not beating normally in atrial fibrillation, blood is not completely emptied from the atria with each contraction. This can result in blood clots forming in the heart. In some patients with atrial fibrillation, these blood clots can dislodge from the atria, resulting in a stroke. The American Heart Association estimates that over 70,000 strokes a year are caused by atrial fibrillation.

Symptoms

	Palpitations
	Irregular heart beat
	Shortness of breath
	Chest discomfort
	Weakness or fatigue
	Lightheadedness or dizziness

Treatments

It is important to realize that a patient's cardiologist will determine what the most appropriate form of treatment will be.

Medication

Digoxin, calcium channel blockers, beta blockers or other antiarhythmic drugs can help regulate the heart rhythm and rate.

Coumadin or other anticoagulants thin the blood and help prevent blood clots and strokes

Cardioversion - low energy electrical shock is applied through the skin to try and shock the heart back into a normal rhythm.

Ablation - after an electrophysiology study is done to map the heart and determine where the atrial fibrillation is coming from, low frequency radio waves are applied to the area, in effect "burning" the source of the arrhythmia so it does not reoccur. Some ablation techniques require a permanent pacemaker insertion.

Cox-Maze Surgery - A surgical procedure developed by James Cox, MD, that permanently repairs atrial fibrillation. Incisions are made in the atria that stop the formation and the conduction of errant electrical impulses and channels the normal electrical impulse in one direction, restoring normal sinus rhythm.