Recovery of Left Ventricular Systolic Function and Clinical Outcomes in Young Adults With Myocardial Infarction

BackgroundLeft ventricular ejection fraction (EF) recovery is associated with better long-term outcomes after myocardial infarction (MI). However, the association between long-term outcomes and EF recovery among young MI patients has not been investigated.ObjectivesThis study sought to evaluate the prevalence of left ventricular systolic dysfunction among patients who experience their first MI at a young age and to compare outcomes between those who recovered their EF versus those who did not.MethodsThe YOUNG-MI registry is a retrospective cohort study of patients who experienced an MI at ≤50 years of age. EF at the time of MI and within 180 days post-MI were determined from all available medical records. The primary outcomes were all-cause and cardiovascular mortality.ResultsThere were 1,724 patients with baseline EF data: 503 (29%) had EF <50%, whereas 1,221 (71%) had a normal baseline EF. Patients with lower EF were more likely to have experienced ST-segment elevation MI, have higher troponin values, and have more severe angiographic coronary artery disease. Among patients with abnormal baseline EF, information on follow-up EF was available for 216, of whom 90 (42%) recovered their EF to ≥50%. Patients who experienced EF recovery had less severe angiographic disease, lower alcohol use, and a lower burden of comorbidities. Over a median follow-up of 11.1 years, EF recovery was associated with an ∼8-fold reduction in all-cause mortality (adjusted hazard ratio: 0.12; p = 0.001) and a ∼10-fold reduction in cardiovascular mortality (adjusted hazard ratio: 0.10; p = 0.025).ConclusionsNearly one-third of young patients presented with left ventricular dysfunction post-MI. Among them, EF recovery occurred in more than 40% and was independently associated with a substantial decrease in all-cause and cardiovascular mortality.