The measurement of plasma lipid levels is now commonly used to assess the risk of coronary heart disease (CHD). Several epidemiological studies have shown that there is a signiﬁcant positive relationship between blood cholesterol levels and deaths associated with CHD (1-3). In the Multiple Risk Factor Intervention Trial (MRFIT), Stamler et al. (4) showed that in a sample of 356,222male subjects, increased blood cholesterol levels were associated with a progressive increase in CHD mortality. However, despite the fact that numerous studies have shown this relationship, Genest et al. (5) have reported that nearly 50% of patients having ischemic heart disease (IHD) have plasma cholesterol levels equal to or even lower than those of healthy subjects.