The number of very old patients admitted to an intensive care unit (ICU) for acute coronary syndrome (ACS) has increased gradually but these patients are underrepresented in randomised clinical trials.

The aim of this study was to analyse mortality of nonagenarians as compared to octogenarians admitted to an ICU for ACS, to describe their management, and to identify prognostic factors.

Patients≥80 years admitted to the ICU (Croix-Rousse University Hospital, Lyon) with a diagnosis of ACS from 1st January 2013 to 31st December 2016 were retrospectively included. After exclusion of type 2 ACS, the data for 311 octogenarians and 92 nonagenarians were analysed using Kaplan–Meier curves and a multivariate Cox-regression model.

More than 70 % of patients received renin-angiotensin-system blockers, beta-blockers, and statins, without significant difference between nonagenarians and octogenarians. Nonagenarians were significantly less treated by ticagrelor than octogenarians (P=0.028). Overall, 97.8 % of patients underwent a coronary angiogram, and 80.4 % percutaneous coronary intervention. At 5 years of follow-up, the survival rate was 62.8 % for nonagenarians as compared to 73.1 % for octogenarians (P=0.007) but no significant difference was observed for cardiovascular mortality (P=0.171). GRACE score and increased age were significantly associated with higher mortality rate, while renin-angiotensin-system blockers, statins, and ticagrelor were protective factors.

Although, overall mortality is higher in patients≥90 years than in those<90 years, the overall survival reported herein remains acceptable. On top of the effect of age, the difference in prognosis according to age may be partly explained by a non-optimal treatment strategy for older patients.