A medical system including an implantable medical, the lead comprising a lead body and a helical electrode at least one of extending or extendable from a distal end of the lead body. The medical system including a hemostasis valve coupled to the lead body proximal the distal end of the lead body, the hemostasis valve configured to slide along the lead body. The distal end of the lead body is configured for insertion into an introducer hub positioned in an opening into a vasculature of a patient and the lead body configured for subsequent advancement through the introducer hub to facilitate securing the hemostasis value to the introducer hub. The hemostasis valve is configured for slidable advancement of the lead body therethrough for continued advancement of the lead body through the introducer hub.