Human embryonic stem cell derived cardiac myocytes detect hERG-mediated repolarization effects, but not Nav1.5 induced depolarization delay

The functional data indicate that hESC-CM are sensitive for detecting repolarization delay induced by hERG channel blockade, and AP prolongation correlated with potency in the hERG channel and IRH assays. However, hESC-CM were less sensitive for detecting depolarizing delay by Na+ channel blockers, and unable to detect delayed repolarization caused by IKs blockade.