In this study, SCN10A-short (S10s), a short transcript encoding the carboxy-terminal domain of the human neuronal sodium channel, was evaluated as a gene therapy target to increase INa and prevent arrhythmias.<h4>Methods</h4>Adeno-associated viral vector overexpressing S10s was injected into wild type and Scn5a-haploinsufficient mice on which patch-clamp studies, optical mapping, electrocardiogram analyses, and ischaemia reperfusion were performed. The gene discussed is SCN5A; the disease is cardiac arrhythmia.