An update on internal mammary artery grafting for coronary artery disease

To describe recent results regarding the use of the internal mammary artery for coronary artery bypass grafting with emphasis on bilateral internal mammary artery grafting, patency, resistance to atherosclerosis, skeletonisation, composite arterial grafts, flow measurement, vasodilatation, and non-invasive imaging techniques.

Coronary artery bypass grafting plays an important part in coronary revascularisation and seems to be associated with a survival benefit in comparison with percutaneous coronary intervention. After 10 years, internal mammary arteries demonstrate better patency than vein grafts except when grafting moderately stenosed right coronary arteries. Bilateral internal mammary artery grafting increases survival further, but carries a higher risk of sternal complications. Skeletonisation may reduce this risk. The internal mammary arteries are used increasingly as composite arterial grafts and this technical solution should no longer be considered experimental. Perioperative flow measurement by the transit-time method is recommended while postoperative echocardiography represents an accurate method for evaluation of flow in internal mammary artery grafts. Multi-detector computed tomography allows for accurate assessment of all types of bypass conduits and native coronary arteries. At present, magnetic resonance imaging of internal mammary artery patency and flow is possible.

Newer studies confirm earlier data with respect to improved long-term survival when using internal mammary artery grafting, and this survival benefit is superior to percutaneous coronary intervention treatment. Bilateral internal mammary artery grafting improves survival further. Skeletonisation of the internal mammary artery provides extra length of grafts for complete arterial revascularisation. Non-invasive imaging techniques are increasingly sophisticated and may change the referral pattern for patients with coronary artery disease to either percutaneous coronary intervention or coronary artery bypass grafting.