Variation in plasma apolipoprotein A-1 and B concentrations following myocardial infarction.

Measurements of plasma apolipoprotein A-1 and B concentrations are increasingly used for the laboratory assessment of risk of coronary artery disease (CAD). This study of 22 patients investigated the response of plasma apolipoprotein A-1 and B levels for up to 20 days following a myocardial infarction. Seven of these patients participated in a clinical trial using the drug Tissue Plasminogen Activator (TPA). We established that, unlike many other plasma proteins, apolipoproteins do not display a classic acute phase response following myocardial infarction, although large variations in plasma apolipoprotein levels were observed in the patients investigated. Our studies also show that the measurement of plasma apolipoproteins A-1 and B to assess future CAD risk in myocardial infarction patients should be deferred for a minimum of at least 14 days post-infarction. No significant difference was observed in the pattern of apolipoprotein response between patients receiving TPA and those not given this drug.