Abstract: A splittable occlusion balloon sheath includes a splittable sheath onto which an occlusion balloon has been secured near the distal end of the splittable sheath. A splittable hemostasis valve or a partitioned hemostasis valve system may also be secured within or to the splittable occlusion balloon sheath. This splittable occlusion balloon sheath is utilized to introduce a medical device, such as electrode leads, into the coronary sinus of the human heart. A dilator may also be used with the splittable occlusion balloon sheath for introduction of the medical devices. The splittable occlusion balloon sheath and/or the dilator may be precurved with a particular shape to assist in the introduction of the splittable occlusion balloon sheath and/or dilator into the coronary sinus. Also disclosed is a process of use of the splittable occlusion balloon system within the coronary sinus.