Background In cardiomyocytes, phosphodiesterases (PDEs) type 3 and 4 are the predominant enzymes that degrade cAMP generated by β-adrenergic receptors (β-ARs), impacting notably regulation of L-type Ca2+ current (ICa,L). Cardiac hypertrophy (CH) is accompanied a reduction in PDE3 PDE4, however, whether this affects dynamic cytosolic ICa,L not known. Methods Results CH was induced rats thoracic ...