Level and prognostic value of serum myeloperoxidase in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention

Background: This study tested the hypothesis that the baseline plasma level of myeloperoxidase (MPO) independently predicts risk of patients with ST-segment elevation (ST-se) acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI). Methods and Results: Plasma MPO levels in 128 patients were examined by ELISA. They were significantly higher in AMI patients than in normal controls (P<0.0001). Patients with a high plasma MPO level (≥1,150 ng/ml) had significantly higher white blood cell counts, a higher plasma level of oxidized low-density lipoprotein, higher peak MB fraction of creatine kinase level, significantly lower left ventricular ejection fraction, and significantly higher incidence of 30-day composite major adverse clinical events (MACE) (defined as Killip score ≥3, reinfarction, repeat PCI, or 30-day mortality) than those patients with low plasma MPO level (<1,150 ng/ml) (all P<0.001). Multiple stepwise logistic regression analysis demonstrated that high plasma MPO level (≥1,150 pg/ml) was the most independent predictor of 30-day MACE (P<0.0001). Conclusions: Plasma MPO level is a major independent inflammatory predictor of 30-day MACE in ST-se AMI patients. Evaluation of the circulating MPO level might improve the prediction of unfavorable clinical outcome following AMI.