Prediction of short-term clinical outcome of percutaneous coronary intervention in patients with acute coronary syndrome through myeloperoxidase levels

BACKGROUND The present study assessed the significance of troponin and myeloperoxidase levels in the prediction of major adverse cardiac events (MACE) during the 1st month after percutaneous coronary intervention (PCI). METHODS This prospective, longitudinal study included 100 patients with acute coronary syndrome who underwent PCI. The participants' characteristics were recorded in a questionnaire. Blood samples were obtained before and 24 h after PCI, and troponin, and myeloperoxidase levels were measured. During the 1st month after PCI, death, myocardial reinfarction, and revascularization during admission were investigated through weekly phone calls. The value of troponin and myeloperoxidase levels before and after PCI in predicting MACE was evaluated using Cox regression. RESULTS Considering the obtained methods and the short duration of the study, 99% of the patients completed the study. Moreover, one death and four cases of myocardial infarction and revascularization were reported. Cox regression did not show significant relations between the incidence of MACE and myeloperoxidase levels before (hazard ratio = 1.12; 95% confidence interval 0.9, 1.39) and after PCI (hazard ratio = 0.86; 95% confidence interval = 0.43, 1.71), or troponin levels before (hazard ratio = 0.97; 95% confidence interval = 0.81, 1.17) and after PCI (hazard ratio = 1.03; 95% confidence interval = 0.96, 1.11). CONCLUSION It seems that the few cases of MACE, due to the small sample size and short duration of follow-up, had been insufficient for determining the predictive value of troponin and myeloperoxidase levels before and after PCI. Therefore, further studies with larger sample size and longer follow-up duration are recommended.