Background and Objective:
The outcome of patients with acute myocardial infarction (AMI) may vary substantially based on baseline risk. This work aims to analyse the impact of gender, age and heart failure (HF) on mortality trends, based on a nationwide, comprehensive and universal administrative database of AMI.

Methods:
This is a nationwide cohort study enrolling patients admitted with AMI from 2009 to 2018 in all Italian hospitals. The main outcomes were in-hospital mortality rate (I-MR) and 1-year post-discharge mortality rate (1-Y-MR).

Results:
Among the 1,000,965 AMI events included in the analysis, 43.6% occurred in patients aged ≥75 years, 34.7% in females and 21.8% in AMI complicated by HF at the index hospitalization. Both I-MR and 1-Y-MR significantly decreased over time (from 8.87% to 6.72%; mean annual change − 0.23%; confidence intervals (CI): − 0.26% to − 0.20% and from 12.24% to 10.59%; mean annual change − 0.18%; CI: − 0.24% to − 0.13%, respectively). This trend was confirmed in younger and elderly AMI patients, in both sexes. Since I-MR has decreased more than 1-Y-MR, the ratio between 1y PD-MR and I-MR increased over time. In AMI patients complicated by HF, both I-MR and 1-Y-MR were markedly high, regardless of age and gender.

Conclusions:
This contemporary, nationwide study suggests that I-MR and 1-Y-MR are still elevated, albeit decreasing over time. Elderly patients and those with HF at the time of index admission, present a particularly high risk of fatal events, regardless of gender.