Atrial flutter is an abnormal heart rhythm that occurs in the atria of the heart. When it first occurs, it is usually associated with a fast heart rate or tachycardia, and falls into the category of supra-ventricular tachycardias. While this rhythm occurs most often in individuals with cardiovascular disease and diabetes, it may occur spontaneously in people with otherwise normal hearts. It is typically not a stable rhythm, and frequently degenerates into atrial fibrillation. However, it does rarely persist for months to years.
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