Globally, about 100 million adults have non-cardiac surgery each year. In the United States, perioperative cardiac complications occur in 0.5-1%, so around one million patients risk cardiac complications and about a quarter will die each year.1 2 Outcomes in Europe are similar to the US.3 Anaesthetists have progressively changed the emphasis on reducing perioperative cardiovascular risk from assessing preoperative coronary artery anatomy to understanding the pathophysiology of perioperative myocardial ischaemia. Despite efforts to identify risk factors for perioperative myocardial ischaemia and potential therapeutic options in the perioperative period, the benefit of giving β blockers and statins at this time remains unclear.2 4 5

Since the early studies that incorrectly attributed survival benefits to perioperative treatment with β blockers,6 rigorous meta-analysis confirmed the need for a large multicentre randomised placebo controlled trial.5 Since then, 1520 patients have been randomised to three studies that have shown no benefit from perioperative metoprolol.7 8 9

The diabetic …