Lipoprotein(a). Clinical approach to a unique atherogenic lipoprotein

SELECTED CASE A 42-YEAR-OLD man was referred because of premature coronary artery disease (CAD). He had been healthy until 3 months earlier, when he sustained a non—Q wave myocardial infarction. Cardiac catheterization revealed severe triple-vessel coronary disease, and he underwent coronary artery bypass grafting. He was not a smoker and had no history of diabetes mellitus or hypertension. Family history was remarkable for a father who died of an acute myocardial infarction at the age of 54 years. Three weeks after surgery, a random serum cholesterol level was 5.38 mmol/L. Physical examination of the patient at the National Institutes of Health revealed no corneal arcus, normal liver and spleen size, and no evidence of palmar, tuberoeruptive, or tendon xanthomas. Laboratory values included a normal fasting blood glucose, normal serum urea nitrogen, and normal serum tests of liver and thyroid function. Fasting plasma lipid and lipoprotein values included the following: triglycerides,