A surgical instrument is configured to aid in performing a procedure of detaching an internal mammary artery (IMA) and the like, from the connecting tissues and side branch vessels which surround the artery in its native location, wherein the detaching procedure is preliminary to the performing of a coronary artery bypass grafting procedure and wherein the IMA is detached via a minimally invasive thoracotomy. To this end, an elongated slender rod includes a handle at its proximal end and an artery engaging loop, arc, fork configuration, or hook at its distal working end. Embodiments may incorporate electrosurgical capability or electrical insulation. A surgeon thus has means for harvesting an intact and undamaged graft vessel from its native location through a minimally invasive incision with enhanced speed, visibility, and freedom of motion.