KCNJ2 and familial long QT syndrome: Such an overlapping clinical phenotype is also observed in calmodulin‐related inherited arrhythmia (Makita et al, 2014), as well as in KCNJ2 mutations causing Andersen‐Tawil syndrome, which can present as LQTS or CPVT phenocopies (Kimura et al, 2012).