Increased High Mobility Group Box-1 Protein Levels are Associated With Impaired Cardiopulmonary and Echocardiographic Findings After Acute Myocardial Infarction

BackgroundSeveral markers of systemic inflammation seem to play an active role in the pathophysiology of acute coronary syndrome and its evolution. High mobility group box-1 (HMGB-1), a ubiquitous nuclear protein constitutively expressed in quiescent cells, was recently recognized as a newer critical mediator of inflammatory diseases. The present study aimed to evaluate the possible association between HMGB-1 levels and structural and functional indices of cardiovascular performance such as cardiopulmonary and Doppler-echocardiography indices in patients after acute myocardial infarction (MI).Methods and ResultsFifty-four consecutive patients (mean age 58.3 years, 83% males) recovering from acute MI were included in the study protocol. All patients underwent Doppler-echocardiography, cardiopulmonary exercise, and HMGB-1 assay. HMGB-1 levels in acute MI patients were significantly higher compared with age- and body mass index–matched controls (14.8 ± 6.8 vs. 2.3 ± 1.0 ng/mL, P < .0001, respectively). Postinfarction patients showed oxygen consumption at peak exercise (VO2peak) = 14.4 ± 4.2 mL·kg·min and a slope of increase in ventilation over carbon dioxide output (VE/VCO2slope) = 32.1 ± 6.2, whereas Doppler-echocardiography values were: left ventricular end-diastolic volume (LVEDV) = 53.4 ± 8.2 mL/m2; left ventricular ejection fraction (LVEF) = 41.7 ± 7.0%. Multiple linear regression analysis (stepwise method) showed that VO2peak (β = –0.276, P = .012), VE/VCO2slope (β = 0.244, P = .005), LVEDV (β = 0.267, P = .018), peak creatine kinase-MB (β = 0.339, P = .004), peak Troponin I (β = 0.244, P = .002), and LVEF (β = –0.312, P = .021) were significantly associated with HMGB-1 levels.ConclusionsThe present study demonstrated that in postinfarction patients, HMGB-1 levels were significantly higher compared with controls, and significantly correlated with cardiopulmonary and Doppler-echocardiography parameters.