Coronary Artery Bypass Graft (CABG) Surgery


  • most common cardiothoracic surgical case seen in ICU
  • Depending on number of vessels (RCA, LAD or LCx) involved patient is described as having
    • Single-vessel disease
    • Double-vessel disease
    • Triple-vessel disease
  • Prognosis depends on
    • Number of vessels involved
    • Left ventricular function
  • can be performed off pump or on pump


  • Usually requires severe stenosis (>70%) with left main stem or triple vessel disease
  • No improved survival seen in patients with single or double-vessel disease
  • Improved survival seen in those with poor left ventricular function
  • Similar survival seen in patients undergoing angioplasty for multi-vessel disease


  • Chest is entered via a median sternotomy
  • Left internal mammary artery (LIMA) is dissected
  • Long saphenous vein can be harvested and prepared by second surgeon
  • Heart is cannulated and patient is placed on bypass
  • Aorta is cross clamped
  • Injury to heart reduced by cardioplegic solutions
  • Cardioplegia can be either warm (37 degrees) or cold (4 degrees)
  • Recent advances include
    • Off-pump coronary artery surgery
    • Minimally invasive direct coronary artery surgery
  • Both can avoid either bypass or median sternotomy


  • Conduits can be either venous or arterial
  • LIMA and long saphenous vein are most common

Long saphenous vein

  • Long saphenous vein is easy to harvest by a second surgeon
  • Allows multiple grafts to be fashioned
  • Patency rate of 60% at 10 years


  • Left internal mammary artery (LIMA) can be used to graft the left anterior descending (LAD) – only need to divide one end (remains attached to LSCA)
  • Patency rate of 90% at 10 years
  • see Factors determining LIMA Flow


  • Bleeding
  • Pericardial tamponade
  • Graft failure (e.g. kinking, disconnection)
  • Atrial fibrillation
  • Wound infection
  • Poor cardiac function
  • Stroke
  • subclavian-coronary steal (if LIMA graft and proxinal left subclavian artery stenosis)

References and Links


CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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