Myocardial revascularisation in high-risk subjects

### Learning objectives The synergistic effect of comorbidity, coronary artery lesion complexity and left ventricular (LV) systolic function can significantly increase the risk of adverse events at the time of myocardial revascularisation (figure 1). In patients with LV dysfunction and a large territory of ischaemia who have little reserve, further reductions in blood pressure can result in a spiral of haemodynamic compromise, culminating in cardiogenic shock or even death. In this article, we address factors that confer increased risk, current tools to quantify and guide revascularisation strategy in such patients; concluding with interventions to minimise risk including haemodynamic support devices, involvement of the heart team and technical considerations during procedural planning. Figure 1 Factors increasing the risk of myocardial revascularisation. LMS, left main stem; LV, left ventricle. ### Comorbidity An increasing number of revascularisation procedures are performed in patients over 70, despite poor representation in randomised controlled trials (RCT).1–3 Elderly patients are more likely to present with extensive coronary artery disease (CAD), higher lesion complexity and multiple comorbidities. Increasing age is associated with up to fourfold increased risk of death, myocardial infarction (MI), stroke, renal failure and bleeding, following percutaneous coronary intervention (PCI), in both the acute and elective setting.4 5 Older age is also a predictor of in-hospital mortality and stroke following coronary artery bypass grafting (CABG) surgery, with the worst outcomes in those following urgent and emergency surgery.3 6 7 There is often disparity between chronological and biological age, which is more difficult to quantify. ‘Frailty’, a syndrome of physical functional decline, malnourishment, cognitive impairment and reduced physical capacity to stressors, is itself associated with adverse outcomes.8 9 The Charlson comorbidity index attempts to address some of these additional factors and has been shown to predict 1-year mortality in cardiac …