Murphy A, et al. - In a large established multicentre registry (the Melbourne Interventional Group registry), the prognostic significance of established coronary artery disease (CAD) was investigated in consecutive patients who presented with acute coronary syndromes (ACS) and had percutaneous coronary intervention (PCI) between 2005 and 2015. The established CAD cohort used in this study included patients with a history of MI (myocardial infarction), PCI or coronary artery bypass graft surgery (CABG). Assessments were made for 12-month mortality and 12-month major adverse cardiovascular events (MACE), primary endpoints. This study included overall 12,878 ACS patients, of whom, 3542 (28%) patients had established CAD. The most prominent presentation in the established CAD cohort (45.1%) was non-ST elevation myocardial infarction (NSTEMI). In the de novo CAD cohort, the most prominent presentation was ST-elevation myocardial infarction (STEMI). Findings revealed a higher rate of MACE at 12 months in patients with a history of myocardial infarction or previous revascularisation, but these subjects did not appear to have higher mortality.