Very Young Adults With Myocardial Infarction Undergoing PCI: Insights From the Houston Methodist Young‐MI PCI Registry

BACKGROUND: Cardiovascular risk prediction models and prevention guidelines, which primarily target adults > 40 years, may underestimate risk in very young patients (≤ 40 years). Data on angiographic characteristics and clinical outcomes in this population remain limited. AIMS: To compare angiographic characteristics and long-term outcomes in very young adults (≤ 40 years) with ACS treated with PCI versus adults aged 41-50 years. METHODS: We analyzed the Houston Methodist Young ACS-PCI Registry, a retrospective cohort of adults aged ≤ 50 years undergoing PCI for acute coronary syndrome (ACS) from 2010 to 2022, excluding those with known coronary artery disease. Clinical variables and angiographic findings were abstracted from electronic health records and catheterization review. Outcomes were major adverse cardiovascular events (MACE: all-cause mortality, myocardial infarction, or stroke) and all-cause mortality. Cox proportional hazards models estimated adjusted hazard ratios (HR) with 95% confidence intervals (CI), adjusting for sex, race, hypertension, dyslipidemia, diabetes, smoking, and obesity. RESULTS: Among 469 patients (median age 46 [42-50] years; 25% women), 78 (17%) were very young (≤ 40 years) and 391 (83%) were 41-50 years. Very young adults had lower hypertension prevalence (67% vs. 81%) and higher ST-elevation MI rates (33% vs. 15%). Multivessel disease prevalence was similar (28% vs. 25%), and the left anterior descending artery was the most common culprit (50%). Over a median follow-up of 3.0 years, mortality was 11% in very young adults and 9% in young adults (p = 0.62). There were no significant differences in adjusted all-cause mortality (HR 1.15; 95% CI 0.25-5.16) or MACE (HR 1.22; 95% CI 0.51-2.96). CONCLUSION: Very young adults comprised ~1 in 6 ACS patients undergoing PCI, presented more often with STEMI, and had a comparable angiographic burden and long-term outcomes to adults aged 41-50 years.