Clinical characteristics and outcomes of young patients with acute myocardial infarction: YAMI registry

INTRODUCTION: Premature myocardial infarction (MI) is characterized by diverse pathophysiology. Despite its low prevalence, it bears serious health and social consequences. OBJECTIVES: The aim of the study was to evaluate young MI patients (≤45 years) in terms of clinical characteristics and long‑term outcomes. PATIENTS AND METHODS: This is an observational study including 221 patients aged 45 years or younger (women, 16.7%; mean SD age, 38.4 4.8 years) hospitalized due to acute MI between January 2017 and April 2023. Data were extracted from the Academic Repository of Clinical Cases of Medical University of Silesia. The young MI patients were compared with a representative MI cohort older than 45 years (n = 2256). The mean (SD) follow‑up was 648.7 (178.7) days. The primary end point was all‑cause mortality. RESULTS: The patients with MI aged up to 45 years were predominantly men (83.3%), and were characterized by lower mortality (7.2% vs 15%; log‑rank P = 0.01), shorter hospitalization time (median interquartile range, 4 3-6 vs 5 3-6 days; P = 0.03), and less pronounced cardiovascular risk factors than the older group. The Cox regression analysis showed that in the MI patients aged up to 45 years, occurrence of peri‑MI sudden cardiac arrest, Q wave presence, higher volume of contrast, and a lack of qualification for cardiac rehabilitation (CR) were independent predictors of mortality. In 15.8% of the younger cohort, MI was unrelated to ruptured atheroma. The patients with nonclassic MI pathophysiology were younger, more often female, more frequently presented with acute non-ST‑segment elevation MI, had lower prevalence of hyperlipidemia and hypertension, and were less often referred for percutaneous coronary intervention and CR, and more often for optical coherence tomography and cardiac magnetic resonance imaging, as compared with the individuals with classic MI. CONCLUSIONS: Young MI patients have a favorable prognosis and frequently present with atypical MI pathophysiology. Participation in CR is of utmost importance in mortality reduction regardless of patient age.