Q: What is atrial fibrillation?

A: It is an abnormal heart rhythm that originates in the top of the heart. This causes the heart to race, potentially giving the patient a sensation of a rapid and irregular heartbeat, shortness of breath or weakness. Secondly, it thickens the blood and can potentially cause blood clots. This abnormal rhythm can be caused by factors such as chronic high blood pressure, lung disease and heart valve disease. Sometimes the cause is never known. It generally affects older individuals, but at times we see this in younger patients, even teenagers. Atrial fibrillation is diagnosed with an electrocardiogram (EKG), a painless way to measure the heart's electrical activity. We treat patients with medicine to slow the heart and relax it, and we also prescribe some form of blood thinner to protect against stroke, the most feared complication of thickened blood. On the correct medicine, patients usually have an excellent prognosis in regards to the atrial fibrillation.

- Dr. Michael Christian Allan, Diagnostic Cardiology Group; member, Chattanooga-Hamilton County Medical Society

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