Objective To study the change of neutrophil myeloperoxidase index(MPXD in acute coronary syndrome(ACS) and its clinical application. Methods 57 cases of MPXI from May to August 2011 were selected and divided into the unstable angina pectoris(UAP) group(20 cases),non-ST-elevation myocardial infarction(NSTEMI) group(20 cases) and the ST-elevation myocar- dial infarction(STEMI) group(17 cases). Contemporaneous 20 individuals with healthy physical examination were selected as con- trols. The indexes such as MPXI and cardiac troponin ...