Abstract: Objective　To screen the most significantly changed metabolite in the sera of patients suffering from ischemic heart disease（IHD）, and investigate its clinical significance. Methods　A total of 10 biochemical parameters involved in the diagnosis of ischemic diseases or infarction were determined including alanine aminotransferase（ALT），aspartate aminotransferase（AST），gamma-glutamyltransferase（GGT），alkaline phosphatase（ALP），lactate dehydrogenase（LDH），alpha-hydroxybutyrate dehydrogenase（α-HBDH），creatine kinase-MB（CK-MB），creatine kinase（CK），C reactive protein（CRP） and cardiac troponin（cTnT） between 52 IHD patients and 45 controls. A strategy of high performance liquid chromatography-mass spectrometry（HPLC-MS） technique was used to explore the major metabolic changes in the sera of the 2 groups in view of metabolomics. The acquired data were subjected to the significance analysis to select and identify the most importantly changed metabolite. Results　The results showed that 4 ion fragments were found between the 2 groups，whose average mass charge ratios （m/z） were 496.33，478.34，184.13 and 991.71. They were finally confirmed to be originated from 1-palmitoyl-sn-glycero-3-phosphocholine（C16：0）. The concentration of this metabolite was （76.35±18.28）μmol/L in IHD patients，which was higher than that in the controls [（64.24±15.56）μmol/L，P＜0.001]. The 9 traditional serum parameters were not different between the patients and the controls（P＞0.05）, except the slightly elevated AST in the IHD group （P＜0.05）. Receiver operating characteristic（ROC） curve indicated that area under the curve of 1-palmitoyl-sn-glycero-3-phosphocholine（C16：0）（0.90±0.03） was larger than that of the other traditional biochemical parameters（P＜0.05）. Conclusions　1-palmitoyl-sn-glycero-3-phosphocholine（C16：0） has clinical significance for the diagnosis of IHD.

Key words: 1-palmitoyl-sn-glycero-3-phosphocholine, Ischemic heart disease, Liquid chromatography-mass spectrometry