GJC1 and atrioventricular block: While this study primarily emphasizes Cx43’s contribution to ventricular electrical conduction, the pathogenesis of atrioventricular block may involve dysregulation of other connexins (e.g., Cx40, Cx45) or ion channels (Hagendorff et al., 2001; Cruz et al., 2024; Li et al., 2021).