Atrial fibrillation is the most common heart arrhythmia in the U.S. Often going undiagnosed, AFib prevalence estimates vary between 2.7 million and 6.1 million Americans.
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Prevalence of Diagnosed Atrial Fibrillation in Adults: National implications for rhythm management and stroke prevention: the AnTicoagulation & Risk Factors in Atrial Fibrillation (ATRIA) study. JAMA. 2001; 285(18). http://jama.jamanetwork.com/article.aspx?articleid=193807