KCNA1 and atrial fibrillation: kcna1–/– mice exhibited increased susceptibility to atrial fibrillation [44] and recent studies from kcna1–/– mice and isolated cardiac myocytes demonstrated that Kv1.1 channels can control heart rhythm both indirectly, through the parasympathetic nervous system, and directly, by contributing to the outward potassium current that promotes cardiac repolarization [44,45,46].