Reasons for occluded LIMA after a by-pass

[alitl1]

I need to know what could cause a LIMA to close after a by-pass?

[kenkeith]

Health insurance claims adjuster in another life.  Exposure to medical terminology, disease etiology and anatomy, legal issues, research, etc.  Computer hardware and software.

Hope my answer to your post provides an understanding to your question.

[alitl1]

Are you a Heart Surgeon?
I am not and I know the technical terms so I just wanted to ask.

[kenkeith]

The cause can be thrombosis (blood clot) and less likely a localized spasm.
Can be due to surgical technique; the most common location for impaired flow in a LIMA graft is the distal anastamotic (connection) site....this can be due to suboptimal surgical technique.

Early graft failure may also be caused by hemodynamic instability or sustained ventricular tachycardia. LIMA grafts achieve improved long-term integrity compared to saphenous vein grafts, which have a 10% incidence of closure within 60 days of CABG. However, LIMA graft failure can  occur due to injury during harvesting of the graft, technical problems with the anastomosis (connecting location), poor distal runoff in the grafted native vessel, extreme mechanical “kinking” of the graft, or undetected subclavian artery stenosis (narrowing).