What are the benefits of using the Internal Mammary Artery (IMA) for Coronary Artery Bypass Grafting (CABG)?
Using the Internal Mammary Artery (IMA) for Coronary Artery Bypass Grafting (CABG) has been shown to improve survival rates, reduce the incidence of late myocardial infarction (MI), hospitalization for cardiac events, need for reoperation, and recurrence of angina. Studies have also demonstrated improved morbidity and mortality rates when both IMAs are used for grafting. In addition, the IMA is resistant to the development of atherosclerosis due to the continuous internal elastic lamina that prevents smooth muscle cell migration and the release of prostacyclin and nitric oxide, potent vasodilators and inhibitors of platelet function, by the endothelium of IMAs. However, there are some potential drawbacks of using the IMA, such as the possibility of spasm and eventual atrophy if used to bypass a coronary artery without a flow-limiting stenosis.  