Abstract: Objective　To investigate the early diagnosis and risk stratification significance of the determination for serum heart-type fatty acid-binding protein (H-FABP) and myeloperoxidase (MPO) in elderly patients with non-ST-segment elevation acute coronary syndrome (NSTE ACS).   Methods　The 107 patients with NSTE ACS were classified into 2 groups according to the severity of patient′s condition，unstable angina pectoris (UAP) group (38 cases) and non-ST-segment elevation myocardial infarction (NSTEMI) group (69 cases). According to the coronary narrow degree, they were classified into mild narrow group (49 cases)，moderate narrow group (24 cases) and severe narrow group (34 cases). The 107 patients were classified into 3 groups: single-vessel disease group (37 cases)，double-vessel disease group (30 cases) and multi-vessel disease group (40 cases) according to the coronary lesion involving range. The 107 patients were classified into 3 groups： low risk group (51 cases)，average risk group (40 cases) and high risk group (16 cases) according to the global registry of acute coronary event (GRACE) risk score. The levels of serum H-FABP and cardiac troponin I (cTnI) in the 107 patients with NSTE ACS and 31 healthy controls were detected by bidirectional lateral flow immunoassay, and the levels of serum MPO were detected by enzyme-linked immunosorbent assay. The high sensitive C reaction protein (hs-CRP) was determined by latex enhanced immuno-trubidimetry. Results　The levels of serum H-FABP，MPO, cTnI and hs-CRP in NSTEMI group were significantly higher than those in UAP group and the healthy control group (P＜ 0.05), and the levels in UAP group were significantly higher than those in the healthy control group (P＜0.05). In the NSTE ACS group, the levels of serum H-FABP and MPO had close relations with the coronary narrow degree，the coronary lesion involving range and GRACE risk score. The higher the levels of serum H-FABP, MPO and hs-CRP in the NSTE ACS group were，the higher the coronary narrow degree，the coronary lesion involving range and GRACE risk score were. The serum H-FABP, MPO and hs-CRP levels had statistical significance between the groups (P＜0.01), and the levels of H-FABP, MPO and hs-CRP in the coronary narrow degree, the coronary lesion involving range and GRACE risk score groups were higher than those in the healthy control group (P＜0.01). There was a positive correlation of H-FABP with MPO and hs-CRP in the NSTE ACS patients (r=0.555 0 and 0.526 0，P＜0.01). Conclusions　The H-FABP and MPO levels are the biomarkers in NSTE ACS patients. The levels of serum H-FABP and MPO in the NSTE ACS patients have close relations with the coronary narrow degree，the coronary lesion involving range and GRACE risk score. The H-FABP and MPO have the early diagnosis and risk stratification significance in elderly patients with NSTE ACS.

Key words: Heart-type fatty acid-binding protein, Myeloperoxidase, Non-ST-segment elevation acute coronary syndrome