ST elevation myocardial infarction in a young population: do we find baseline and clinical differences in this population subgroup?

The incidence of STEMI increases with age, being less common in young population. Given the future morbidity and mortality associated with this condition in these population subgroups, it is useful to analyse the baseline and in-hospital characteristics of these patients (p).

Our objective is to analyse and compare baseline characteristics, cardiovascular risk factors, and in-hospital evolution in p aged between 40 and 50 and those under 40 admitted for STEMI to the CICU at our hospital.

We conducted a retrospective analysis of a total of 7,205 p admitted to the cardiovascular critical care unit (CICU) of our hospital, of which 3046 had a diagnosed of STEMI, analyzing those who were between 40 and 50 years old, as well as under 40, between the years 2012 and 2024.

A total of 385 p (56 p under 40 years (1,83%) and 329 between 40 and 50 years (10,8%) were included. The mean age was 35.5 ± 3.8 years and 45.8 ± 2.6, respectively, with a male predominance (85.7 and 86%). The <40 group had a higher percentage of diabetes (19.6 vs 14.3%), with greater insulin use (12.7 vs 5.2%); however, hypertension (HTN) and dyslipidaemia (DLP) were more frequent in the 40–50 group (34.3 vs 21.4% and 40% vs 33.9%). The <40 group had a higher percentage of smokers (83.9 vs 73.3%), cocaine users (28.6 vs 10.3%), and alcohol abuse (10.7 vs 9.1%). There was a higher prevalence of ischaemic heart disease (7.9 vs 3.6%) and stroke (3.3 vs 0) in the 40–50 group.

Most patients were admitted in Killip class I (69.6% in <40 years and 73.9% in 40–50 years). Most STEMIs involved single-vessel disease (70.9% in <40 years and 71.6% in 40–50 years). The most frequently implicated coronary artery was the LAD in 61.8% of cases in the <40 group and 53.5% in the 40–50, with 100% of patients receiving ASA and 57% of <40 patients and 65% of 40–50 patients receiving Prasugrel.

There was a higher percentage requiring DBT (14.3% vs 7.3%) in <40 years, with similar use of Noradrenaline (10.7 vs 9.7%) and IABP (3.6 vs 3%). A greater number of p in the <40 group required invasive mechanical ventilation (IMV) (8.9 vs 4.3%).

Ventricular fibrillation (VF) and/or primary ventricular tachycardia (VT) had a higher incidence in the <40 group (20 vs 7.6%), as well as developing paroxysmal AF (5.4 vs 3.6%). No deaths occurred during the CICU stay in the <40 group, unlike the 40–50 where 4 patients died.