Hi - I am trying to help a student with the following question........
I am rusty on ICD-9 procedures, so I need some help:

The patient was taken to OR where he underwent a saphenous vein graft to the obtuse marginal and posterior descending and an internal mammary graft to the left anterior descending. During the surgery, the second obtuse marginal was dissected free but deemed unbypassable because it was less than 1 mm. The patient tolerated the procedure and came off the cardiopulmonary bypass pump without problems.

36.12, 36.15, 39.61 - Are the codes I came up with - but I am not sure if I am on the right track.

Any help you could provide would be appreciated!