Atrial fibrillation (AF) is often managed by general internal medicine physicians. Available data suggest that guidelines regarding AF management are often not followed, but the reasons for this remain unknown. The aim of this study was to assess the knowledge and beliefs of internists regarding strategies to treat AF. A national electronic survey of internal medicine physicians regarding their perceptions of optimal AF management, with an emphasis on the rationale for choosing a rhythm- or rate-control strategy, was conducted. One hundred forty-eight physicians from 36 different states responded (representing > or =19% of unique e-mails opened). Half the respondents reported managing their patients with AF independently without referral to cardiologists. Seventy-three percent of participants believed that a rhythm-control strategy conveys a decreased stroke risk, 64% believed that there is a mortality benefit to rhythm control, and 55% thought that it would help avoid long-term anticoagulation. Comparing those who preferred a rhythm-control strategy to everyone else, those who favored rhythm control statistically significantly more often believed that rhythm control reduces the risk for stroke (96% vs 67%, p = 0.009) and that rhythm control allows the discontinuation of anticoagulation therapy (76% vs 49%, p = 0.045). In conclusion, contrary to available data in clinical trials and recent guidelines regarding the rationale for choosing a rhythm-control strategy in treating patients with AF, most study participants believed that rhythm control decreases stroke risk, decreases mortality, and allows the discontinuation of anticoagulation therapy. These prevalent misconceptions may substantially contribute to guideline nonadherence.