Cardioprotection: Chances and Challenges of Its Translation to the Clinic

Myocardial infarct size is a major determinant of prognosis. Ischaemic preconditioning with brief coronary occlusion and reperfusion before a sustained period of coronary occlusion with reperfusion delays infarct development. Ischaemic postconditioning uses repetitive brief coronary occlusion during early reperfusion of myocardial infarction and reduces infarct size. Remote ischaemic preconditioning uses brief ischaemia and reperfusion of a distant organ to protect the myocardium. These conditioning protocols recruit a complex signal cascade of sarcolemmal receptor activation, intracellular enzyme activation, and ultimately mitochondrial stabilisation and inhibition of death signalling. Conditioning protocols have been successfully used in patients undergoing elective coronary revascularisation and reperfusion after acute myocardial infarction. Pharmacological recruitment of cardioprotective signalling has also been used to reduce infarct size, but so far without prognostic benefit. Outcomes of cardioprotection are affected by age, sex, comorbidities, and drugs, but also by technical issues related to determination of infarct size and revascularisation procedure.