PRKAG2 and disorder of glycogen metabolism: Most cases of WPW have been linked to pathogenic variants in PRKAG2 or MYH6, glycogen storage disorders, mitochondrial syndromes, or congenital heart diseases such as septal defects, Ebstein malformation of the tricuspid valve, or HCM (Bowles et al., 2015; Ehtisham & Watkins, 2005).