Question:

What happens when a left internal mammary artery (LIMA) fails to mature?

If a LIMA fails to mature, are there likely to be any side effects, or will I need future treatment for this? If so what types?

Submitted by Bryan from Kentucky on 07/21/2017

Answer:
by James J. Livesay, MD

The LIMA has the best long term patency and effects late survival better than any other treatment for coronary artery disease. Unfortunately, the LIMA is not perfect in all patients. Failure of the LIMA to provide adequate flow has been shown in 5 to 10% of late angiographic studies at 10 years. This may be because the native artery is not significantly narrowed and there is too much competitive flow from the native artery, or because there is severe occlusive plaque in the distal artery which limits flow to the territory of muscle supplied by the diseased artery. In some cases, the LIMA is injured during the original operation in taking it down. If the LIMA is not functioning, the alternatives are the same as before, either a coronary stent placed in the native artery or another bypass graft procedure using a new graft.