ALDH7A1 and atrial fibrillation: Our study shows that AF is associated with (1) a cAMP/PKA-dependent reduction of the ICa,L density, (2) the upregulation of cAMP/PKA-dependent stimulation of SR Ca2+ release events large enough to produce ITI, and 3) PDE-dependent specific cAMP signaling in each relevant compartment for Ca2+-handling regulation.