KCNH2 and Familial short QT syndrome: Initial analysis of the family 1 index patient using a targeted Next Generation Sequencing (NGS) gene panel including the SQTS genes, known to be associated with SQTS at that time (CACNA1C, CACNB2, KCNH2, KCNQ1, and KCNJ2, Supplementary Table 2) revealed no pathogenic mutations.