The role of markers of endothelial dysfunction, oxidative and cellular stress in the prediction of myocardial infarction in comorbid patients with stable coronary heart disease

Aim. To study the role of markers of endothelial dysfunction, oxidative and cellular stress in the prediction of myocardial infarction (MI) in comorbid patients with stable coronary heart disease (CHD).

Material and methods. The study involved 336 patients with a diagnosis of CHD. The presence of CHD was confirmed by diagnostic coronary angiography with the calculation of the Gensini index. All patients were divided into 2 groups: group 1–288 patients without a history of MI, group 2–48 patients with a history of MI. All patients were assessed for the levels of oxidized modified proteins, high-sensitivity C-reactive protein (hs-CRP), homocysteine, heat shock protein (HSP70), and superoxide dismutase activity.

Results. All patients were comparable in age. For other clinical and anthropometric characteristics, we saw significant differences (according to the Mann–Whitney criterion): patients with previous MI had higher BMI, waist circumference, and blood pressure. The correlation analysis revealed positive significant average strength relationships between past MI and the Gensini index, low-density lipoprotein level, total cholesterol level, homocysteine level, hs-CRP level, and the level of oxidized modified proteins; and negative significant average strength relationships between past MI and SOD activity level (r=-0.374, p=6.4 E-07) and HSP70 level (r=-0.563, p=2.6 E-15). The ROC analysis revealed that not all markers were significant in predicting the risk of MI. It is shown that the most expected characteristics were shown by the hs-СRP. However, further analysis of the predictive significance of the markers demonstrated that the addition of HSP70 to hs-CRP increases the predictive significance of hs-CRP in relation to the risk of developing MI.

Conclusion. We have demonstrated that a strategy using a cumulative risk assessment consisting of 2 biomarkers (individually involved in inflammation and stress-induced cellular responses) can identify patients with an established diagnosis of CHD who have an increased risk of acute MI.