We also demonstrate that grafting lentivirus-transduced Connexin 43 overexpressing myofibroblasts into the lesion resulted in increased Connexin 43 protein content and strong protection against ventricular arrhythmias in vivo, as their incidence was reduced by ~ 50% at 2- and 8 weeks after myocardial infarction. The gene discussed is GJA1; the disease is Ventricular arrhythmia.