'Conditioning' the heart during surgery.

Coronary heart disease (CHD) is the leading cause of death worldwide. Coronary artery bypass graft (CABG) surgery remains the procedure of choice for coronary artery revascularisation in a large number of patients with severe CHD. However, the profile of patients undergoing CABG surgery is changing with increasingly higher-risk patients being operated upon, resulting in significant morbidity and mortality in this patient group. Myocardial injury sustained during cardiac surgery, most of which can be attributed to acute myocardial ischaemia-reperfusion injury, is associated with worse short-term and long-term clinical outcomes. Clearly, new treatment strategies are required to protect the heart during cardiac surgery in terms of reducing myocardial injury and preserving left ventricular systolic function, such that clinical outcomes can be improved. 'Conditioning' the heart to harness its endogenous cardioprotective capabilities using either brief ischaemia or pharmacological agents, provides a potentially novel approach to myocardial protection during cardiac surgery, and is the subject of this review article.