The study of serum apoprotein levels as indicators for the severity of angiographically assessed coronary artery disease.

Serum apoprotein A-I (Apo A-I) and B (Apo-B) concentrations were determined in 40 subjects undergoing coronary angiography for past myocardial infarction and angina pectoris, and the authors studied the relationship between the apoprotein concentrations and the severity of coronary artery disease (CAD). During this study, serum total cholesterol, triglyceride, and high-density lipoprotein, low-density lipoprotein, and very low density lipoprotein cholesterol concentrations were determined to control analysis. The results showed that the decrease in serum Apo A-I levels was the best indicator distinguishing CAD from non-coronary artery disease; the Apo B/Apo A-I ratio had the most consistent association with the severity of CAD as assessed by angiography; Apo B/Apo A-I values ranging from 0.98 to 1.00 might be considered critical values for early CAD.