The usefulness of myeloperoxidase in prediction of in-hospital mortality in patients with ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention.

BACKGROUND: The predictive value of myeloperoxidase (MPO) in ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (PCI) has not been established. The aim of the present study was to investigate MPO as a predictor of in-hospital mortality in STEMI patients treated by primary PCI.

METHODS: Study population consisted of 189 STEMI patients having undergone primary PCI. Plasma MPO level was measured 24 hours after symptom onset using chemiluminescent microparticle immunoassay (Abbott Diagnostics, Germany). The Receiver Operating Characteristic analysis was performed to identify the most useful MPO cut-off level for the prediction of in-hospital mortality. The patients were divided into two groups according to the cut-off MPO level: high MPO group (> or = 840 pmol/L, n = 65) and low MPO group (< 840 pmol/L, n = 124).

RESULTS: The high MPO group had significantly more frequent anterior wall infarctions (p < 0.001) and Killip class > 1 on admission (p = 0.013) as well as lower left ventricular ejection fraction (LVEF) (p = 0.011) and higher B-type natriuretic peptide (BNP) (p = 0.029) than the low MPO group. The incidence of in-hospital mortality was 5.8% and was significantly higher in the high MPO group (13.8%) than in the low MPO group (1.6%) (p = 0.001). Multiple logistic regression analysis identified the plasma MPO level as an independent predictor of in-hospital mortality (OR 3.88, 95% CI 1.13 - 13.34, p = 0.031).

CONCLUSIONS: Plasma MPO level independently predicts in-hospital mortality in STEMI patients treated by primary PCI.