Proteomic analysis of blood samples was performed using 2D electrophoresis after purification from albumin and immunoglobulin G. It was found that a low level of haptoglobin and its isoforms in blood plasma, as well as the presence of its α2-α2 genotype, are associated with a more severe class of heart failure and a negative prognosis of the myocardial infarction course. This evidence concerns the gene HP and myocardial infarction.