Disclosed herein is a catheter for delivering an implantable medical lead to an implantation site near an ostium leading to a proximal region of a coronary sinus. The catheter includes a distal end, a proximal end opposite the distal end, a tubular body extending between the distal and proximal ends, an atraumatic fixation structure defining a distal termination of the distal end, and a lead receiving lumen. The atraumatic fixation structure is configured to enter the ostium and passively pivotally anchor with the proximal region of the coronary sinus. The lead receiving lumen extends along the tubular body from the proximal end to an opening defined in a side of the tubular body near the distal end and proximal the atraumatic fixation structure.