A system and method for navigating coronary vasculature involves use of a guide catheter system which includes a guide catheter, a navigator catheter longitudinally displaceable within the guide catheter, and a deflection arrangement provided at a distal end of the navigator catheter. The guide catheter is advanced to at least a patient's coronary sinus ostium, and the navigator catheter is extended from the guide catheter to a location proximate or within an angled vein distal to the coronary sinus ostium. Using the deflection arrangement, a guide wire passing through the navigation catheter is directed into the angled vein. A lead having an open lumen is advanced over the guide wire to direct the lead to an implant site within the angled vein.