Serum myeloperoxidase level predicts reperfusion in patients with myocardial infarction receiving thrombolytic therapy

Abstract

Polymorphonuclear leukocytes play a central role in all stages of the atherothrombotic inflammatory process. The atherothrombotic activity of polymorphonuclear leukocytes is exerted by mediators such as myeloperoxidase (MPO). Although the role of MPO has been studied with respect to the development of adverse cardiac events in acute coronary syndromes (ACS), the association of this molecule with effectiveness of reperfusion in patients receiving thrombolysis is not yet known. The study population consisted of a total of 158 patients with acute coronary syndromes. Final diagnosis was ST-segment elevation myocardial infarction in 86 patients, 80 of whom received thrombolysis. Blood samples were drawn at presentation of the patients and serum myeloperoxidase levels were measured. Reperfusion was defined in terms of electrocardiographic ST-segment resolution. The serum levels of MPO were found to be correlated with rates of in-hospital adverse events including death (P < 0.001), reinfarction (P < 0.001), recurrent ischemia (P < 0.001), arrhythmias (P < 0.001), clinical heart failure (P < 0.001), and cardiogenic shock (P < 0.001). There was a significant difference in serum MPO levels between subjects with three-vessel disease and two- or one-vessel disease (P < 0.001). Pre-lytic serum high-sensitivity C-reactive protein levels in patients with successful reperfusion were lower than in patients with failed reperfusion (P < 0.001). Analysis of patients with ST segment elevation myocardial infarction receiving thrombolytic therapy revealed that pre-lytic serum MPO levels in patients with successful reperfusion were significantly lower than those of patients with failed reperfusion (P < 0.001). In the present study, serum MPO levels were found to be a strong predictor of response to thrombolytic treatment in patients with ST-segment elevation myocardial infarction. Therefore the level of inflammatory activity in acute coronary syndromes seems to influence the effectiveness of fibrinolysis.

Response to Letter Regarding Article, “High Levels of Systemic Myeloperoxidase Are Associated With Coronary Plaque Erosion in Patients With Acute Coronary Syndromes: A Clinicopathological Study”

“…In our study, we used serum collection tubes as they had been used in a previous large observational study enrolling patients with acute coronary syndromes where MPO levels were found to predict the clinical outcome. 4 Similar studies have also reported an association between serum MPO levels and myocardial reperfusion after thrombolysis 5 and systemic inflammation after a primary percutaneous coronary intervention, 6 thus indicating that MPO measured in serum is clinically meaningful. Finally, the findings in our clinical study are consistent with those in our postmortem tissues from sudden coronary deaths that showed a higher density of MPO-positive cells in thrombi overlying eroded lesions relative to plaque rupture.…”

Myeloperoxidase: New Roles for an Old Molecule

“…In these patients, baseline MPO was an independent predictor of in-hospital mortality (OR 3.9, 95% CI, 1.8-7.5). Only one study (42) exa mined the association of the serum MPO level and the response to thrombolytic treatment in 158 patients with ST-segment MI. MPO levels before thrombolysis were significantly lower in patients with successful reperfusion.…”