Atrial fibrillation (AF) is a cardiac arrhythmia that arises from electrical and contractile dysfunction in the atria. Atrial function is regulated by a variety of intracellular signaling networks that facilitate rapid communication and coordinate responses of atrial myocytes. In this issue of the
Thomas J. Hund, Peter J. Mohler
Cardiac atrial signaling “hubs” regulate local calcium signaling.