Acute ST-elevation myocardial infarction in young patients: 15 years of experience in a single center

Abstract

Background: There have been few studies done regarding young patients with ST-elevation myocardial infarction (STEMI). The purpose of this study was to investigate the clinical characteristics and coronary angiographic features in young patients with STEMI.

Methods: We collected data on 849 consecutive patients with STEMI from 1992 to 2006. Baseline clinical characteristics, coronary anatomy, and outcome were compared in young (< or =45 yrs) and older patients (>45 yrs).

Results: Young patients presented 11.6% of all patients with STEMI. These patients were predominantly male (92.9% vs 80.3%, P < 0.001), more likely to smoke (75.8% vs 47.2%, P < 0.001), obese (48.2% vs 27.9%, P = 0.002), have higher triglyceride levels (176.9 +/- 153.8 mg/dL vs 140.7 +/- 112.7 mg/dL, P = 0.005), and lower high-density lipoprotein cholesterol (37.1 +/- 7.9 mg/dL vs 42.8 +/- 14.3 mg/dL, P = 0.005) than older patients. Also, younger patients had a shorter hospital stay (7.1 +/- 4.9 d vs 8.5 +/- 6.7 d, P = 0.04), less in-hospital morbidity (29.3% vs 39.7%, P = 0.02), and mortality (3.0% vs 12.3%, P = 0.002). Killip class III or IV could predict in-hospital morbidity and mortality in young patients. Both groups had similar rates of repeated percutaneous coronary intervention (PCI; 45.5% vs 41.5%, P = 0.23) and reinfarction (6.1% vs 3.2%, P = 0.32). Mortality rate during follow-up was significantly lower in younger patients (3.0% vs 19.6%, P < 0.001).

Conclusion: Cigarette smoking, obesity, and dyslipidemia were the most important modifiable risk factors in young patients with STEMI. These patients had a better outcome than older patients without differences in repeated PCI and reinfarction between them. Only Killip class III or IV could predict in-hospital morbidity and mortality in young patients with STEMI.