Background The rates of very elderly patients (>85 years old) undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) are rapidly increasing. They are under-represented in clinical trials, and those who are included may not reflect the real-world population. We aim to review the clinical characteristics of very elderly patients undergoing PCI for ACS and identify factors associated with adverse outcomes. Method All very elderly patients undergoing PCI for ACS in the Auckland region between January 2014 to December 2016 were included. Baseline clinical and procedural details were obtained, and the primary endpoint was all-cause mortality measured up to a maximum of 4 years. Secondary endpoints include recur rent myocardial infarction, unplanned revascularisation, stroke and major bleeding. Results A total of 186 patients were included for analysis (mean age 87.6 +/- 2.8 years, 51.6% male). Indications for PCI were ST-elevation myocardial infarction (STEMI) in 74 (39.8%), non-ST elevation myocardial infarction (NSTEMI) in 97 (52.2%) and unstable angina in 15 patients (8.1%). Successful PCI was completed in 180 patients. At a maximal follow-up of 4 years (mean 23.4 mo), the rates of all-cause mortality and recurrent myocardial infarction were 22.0% and 14.0% respectively. The risk of mortality was increased by the presence of diabetes (44.8% vs 17.8%, HR=3.0, 95%CI: 1.6-5.9, p=0.001), STEMI (33.8% vs 13.5%, HR=3.1, 95%CI: 1.6-5.9, p=0.001), and reduced eGFR (every -10 mL/min/1.73m(2), HR=1.7, 95%CI: 1.3-2.1, p<0.0001). Major bleeding events while on dual antiplatelet therapy as defined by Bleeding Academic Research Consortium score >= 3 occurred in 14 patients (7.5%; 8 on ticagrelor, 6 on clopidogrel). Conclusion Very elderly patients who undergo PCI for ACS have acceptable survival outcomes. STEMI, diabetes and impaired renal function were predictive of mortality in this elderly cohort.