Myocardial injury: the acute phase response and lipoprotein metabolism

Myocardial infarction and other types of tissue injury generate changes in plasma proteins known as the acute phase response. Variations in lipid and lipoprotein levels after acute myocardial infarction are manifest within 24 to 48 h after the onset of chest pain. Maximal postinfarction reductions in total cholesterol occur at days 4 to 5 with levels 47% below baseline; low and high density lipoprotein cholesterol fractions decrease to their nadir on day 7 to concentrations that are 48% and 32% below baseline, respectively. Triglyceride levels increase after acute myocardial infarction to a maximal level that is 58% above baseline on day 7. These alterations in lipid and lipoprotein levels generally stabilize by 2 months after the acute event. Screening for dyslipidemias in survivors of myocardial infarction requires clinical decision-making based on accurate and reliable measurements. The clinician must be familiar with characteristic changes in acute phase lipids and lipoproteins to ensure that patients receive appropriate, potentially life-saving therapy.