Athscl unsp type bypass of the extrm w gangrene, left leg

This code signifies the presence of atherosclerosis affecting a bypass graft in the left leg, which has progressed to the point of causing gangrene. It indicates a severe form of peripheral artery disease where a previously placed graft to restore blood flow has become diseased and led to tissue death in the lower extremity.

Use this code when documentation clearly states atherosclerosis of a bypass graft in the left leg with associated gangrene. This typically applies to patients with critical limb ischemia following a prior revascularization procedure, where the graft itself has failed due to atherosclerotic changes. Supporting documentation would include physician notes detailing the graft involvement, the specific limb affected, and the presence of gangrene.

• Ensure the documentation specifies "bypass graft" and not a native vessel atherosclerosis.
• Verify the laterality is explicitly "left leg" and that gangrene is present.
• Sequence this code as a primary diagnosis when it is the main reason for the encounter, or as a secondary diagnosis if the gangrene is a complication of another primary condition.