Abstract: Implantable leads of a cardiac stimulus system are disclosed, as well as methods for implanting leads of a cardiac stimulus system. The lead may be comprised of a proximal portion having a coupler for coupling to an implantable pulse generator, an intermediate portion comprising a plurality of electrodes disposed thereon, and a distal portion. The intermediate portion may have a first diameter and the distal portion may have a second diameter. The distal portion may also have an attachment feature for attaching to a lead pulling tool for delivery to an ITV and an intercostal vein. Methods may include pulling a lead from a first position to a second position within the vasculature, exiting the vasculature at the second location, and attaching a portion of the lead that exits the vasculature to an electrode or implantable device for use with the lead.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a guide extension catheter. The guide extension catheter may include a proximal shaft having a first outer diameter. A distal sheath may be attached to the proximal shaft and may have a second outer diameter greater than the first outer diameter. The distal sheath may be designed to extend past a coronary ostium and into a coronary artery so that another medical device can pass therethrough toward the coronary artery. An expandable balloon may be coupled to the distal sheath.