Coronary heart disease is set to become the leading worldwide cause of death by 2020. 1 Acute myocardial infarction is a major cause of such mortality and the best hope of salvaging viable myocardium is by rapid reperfusion of the ischaemic myocardium, either by thrombolysis or primary percutaneous coronary intervention. However, despite such effective reperfusion strategies the long-term benefit is suboptimal—only a third of the life-years lost by myocardial infarction are regained by reperfusion. 2 Potentially lethal reperfusioninduced injury might be involved here. 3 Treatments that directly target the reperfusion phase could provide novel cardioprotection. One such strategy, which might have substantial consequences for the future management of acute myocardial infarction, is ischaemic postconditioning, first described by Zhao and colleagues4 in dogs. Ischaemic postconditioning was achieved by very short repetitive periods of coronary occlusion and reperfusion in the early minutes of revascularisation of experimental myocardial infarction. 5 In a recent landmark clinical study, Patrick Staat and colleagues6, postconditioned the human myocardium in patients undergoing primary percutaneous coronary intervention by repetitively inflating and deflating an angioplasty balloon within minutes of stenting. Using simple enzyme release as an index of infarction, they found that infarct size was reduced by a third.