Serum matrix metalloproteinases in patients resuscitated from cardiac arrest. The association with therapeutic hypothermia

Abstract: Aim: To study the systemic levels of matrix metalloproteinases (MMP) -7, -8 and -9 and their inhibitor TIMP-1 in cardiac arrest patients and the association with mild therapeutic hypothermia treatment on the serum concentration of these enzymes. Methods: MMP-7, -8 and -9 and tissue inhibitor of metalloproteinases-1 (TIMP-1) were analysed in blood samples obtained from 51 patients resuscitated from cardiac arrest. The samples were taken at 24 and 48h from restoration of spontaneous circulation (ROSC). The biomarker levels were compared between patients (N =51) and healthy controls (N =10) and between patients who did (N =30) and patients who did not (N =21) receive mild therapeutic hypothermia. Results: MMP-7 (median 0.47ng/ml), MMP-8 (median 31.16ng/ml) and MMP-9 (median 253.00ng/ml) levels were elevated and TIMP-1 levels suppressed (median 78.50ng/ml) in cardiac arrest patients as compared with healthy controls at 24h from ROSC. Hypothermia treatment associated with attenuated elevation of MMP-9 (p =0.001) but not MMP-8 (p =0.02) or MMP-7 (p =0.69). Concentrations of MMPs -7, -8 and -9 correlated with the leukocyte count but not with C-reactive protein (CRP) or neurone-specific enolase (NSE) levels. Conclusion: We demonstrated that the systemic levels of MMP-7, -8 and -9 but not TIMP-1 are elevated in cardiac arrest patients in the 48h post-resuscitation period relative to the healthy controls. Patients who received therapeutic hypothermia had lower MMP-9 levels compared to non-hypothermia treated patients, which generates hypothesis about attenuation of inflammatory response by hypothermia treatment. [Copyright &y& Elsevier]