Objective:To explore the relationship between changes in levels of thrombomodulin (TM) and non high-density lipoprotein cholesterol (non-HDL-C) with ascending aortic elastic function and degree of coronary artery disease (CHD) in patients with coronary heart disease (CHD).Methods:A total of 147 patients with coronary heart disease diagnosed through coronary angiography at Yulin First Hospital from January 2018 to December 2022 were selected as the CHD group. In addition, 90 volunteers who underwent health examinations at our hospital and did not experience coronary artery disease were selected as the control group. Two groups were compared in terms of blood lipids [triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C)], ascending aortic elastic function parameters [arterial dilation (AD), arterial stiffness index (ASI)], TM, non HDL-C levels, and other indicators, and stratified analysis was conducted according to the number of coronary lesions. The linear correlation analysis method was used to analyze the relationship between TM, non-HDL-C, Gensini score, and ascending aortic elastic function parameters.Results:The serum levels of TG, TC, LDL-C, TM, and non HDL-C in the CHD group were significantly higher than those in the control group, while the HDL-C levels were lower than those in the control group, with statistical significance (all P<0.05). The ASI of the ascending aorta in the CHD group was significantly higher than that in the control group, while the AD was lower than that in the control group, and the differences were statistically significant (all P<0.05). The serum levels of TG, TC, LDL-C, TM, and non HDL-C in CHD patients with multiple coronary artery lesions were significantly higher than those in patients with dual or single coronary artery lesions, and the HDL-C levels were lower than those in patients with dual or single coronary artery lesions, with statistical significance (all P<0.05); The serum levels of TM and non HDL-C in CHD patients with dual coronary artery disease were significantly higher than those in single coronary artery disease patients, and the HDL-C levels were lower than those in single coronary artery disease patients, with statistical significance (all P<0.05). The ASI of CHD patients with multiple coronary artery lesions was significantly higher than that of patients with dual or single coronary artery lesions, and the AD was lower than that of patients with dual or single coronary artery lesions, with statistical significance (all P<0.05); The ASI of CHD patients with dual coronary artery disease was significantly higher than that of patients with single coronary artery disease, and the AD was lower than that of patients with single coronary artery disease, with statistical significance (all P<0.05). The TM, non HDL-C levels in CHD patients were significantly negatively correlated with AD (all P<0.05), and positively correlated with ASI and Gensini scores (all P<0.05). Conclusions:The levels of TM and non HDL-C in CHD patients significantly increase, and the ascending aortic elasticity function was decreased. TM and non HDL-C are related to coronary elasticity function and the severity of coronary artery disease.