Left Internal Mammary Artery as an Endocrine Organ: Insights Into Graft Biology and Long-term Impact Following Coronary Artery Bypass Grafting

Mayo Clin Proc. 2023 Jan;98(1):150-162. doi: 10.1016/j.mayocp.2022.10.003.


The left internal mammary artery (LIMA) is considered the criterion standard vessel for use in coronary artery bypass grafting. In recent decades, countless studies have documented its superiority over other arterial and venous coronary artery bypass grafting conduits, although the full mechanisms for this superiority remain unknown. A growing body of literature has unveiled the importance of extracellular vesicles known as exosomes in cardiovascular signaling and various pathologic states. In this review, we briefly compare the clinical longevity of the LIMA relative to other conduits, explore the effects of varying grafting techniques on clinical and angiographic outcomes, and provide physiologic insights into graft function on a cellular and molecular level. Finally, we explore exosome signaling as it pertains to atherosclerosis in support of the LIMA as an "endocrine organ."

Publication types

  • Review

MeSH terms

  • Angiography
  • Biology
  • Coronary Artery Bypass / adverse effects
  • Coronary Artery Bypass / methods
  • Coronary Vessels / surgery
  • Humans
  • Mammary Arteries* / transplantation