Figure 9b. Preoperative assessment of the existing RIMA graft in a 67-year-old man scheduled for CABG surgery. (a) Axial image shows the portion of the RIMA graft as it crosses near the sternum (arrow). (b) Curved axial MPR image shows the full course of the RIMA graft (arrow) as it crosses the midline to pass directly behind the sternum (S) and anastomose to the circumflex artery (arrowhead). A = transverse aortic arch.