Clinical and biochemical factors associated with prognosis after myocardial infarction at a young age.

OBJECTIVES: This study examined the effect of metabolic disturbances, hemostatic function, coronary artery disease severity and left ventricular function on the long-term prognosis after myocardial infarction in men < 45 years old.
BACKGROUND: Heavy smoking; dyslipoproteinemias involving very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL); a family history of premature coronary artery disease; hyperinsulinemic responses to oral and intravenous glucose challenges; and defective fibrinolytic function characterize the young postinfarction patient, but the influence of these features on the long-term prognosis is virtually unknown.
METHODS: Measurements of hemostatic function and metabolic and angiographic indicators of risk were included in a prospective cohort study of variables predictive of reinfarction, cardiac death and major coronary events within 6 to 9 years in 108 unselected nondiabetic men with a first myocardial infarction before age 45 years.
RESULTS: During follow-up, 20 patients had sudden cardiac death, and 53 had a major coronary event (reinfarction, sudden cardiac death, bypass surgery or intervention by catheterization). In multivariate analysis, VLDL and global coronary atherosclerosis score predicted reinfarction; plasma plasminogen activator inhibitor-1 (PAI-1) activity and global coronary stenosis score predicted cardiac death; and VLDL triglyceride levels, global coronary atherosclerosis score and age predicted any major coronary event.
CONCLUSIONS: This prospective cohort study shows that hypertriglyceridemia, impaired fibrinolytic capacity secondary to plasma PAI-1 activity elevation and extensive coronary artery disease increase the risk of recurrences in men with a first myocardial infarction before age 45 and contribute to the relatively poor long-term prognosis in this patient group.