The mechanistic basis for these cardiac arrhythmias remains essentially unknown since preliminary studies suggest that human ether-a-go-go potassium channel (Kv11.1) protein (HERG) blockade develops only in the supra micromolar range for LBH-589 and VOR (Giles et al., 2006; Kerr et al., 2010). This evidence concerns the gene KCNH2 and cardiac rhythm disease.