Abstract: Objective To investigate the correlation between quantitative parameters of ultrafast pulse wave velocity (ufPWV) technique and serum galectin-3 (Gal-3) and interleukin-33 (IL-33) levels in patients with metabolic syndrome. 
Methods In total, 150 patients with metabolic syndrome were selected as the observation group and divided into three groups: group Ⅰ: 50 patients with normal carotid intima-media thickness (IMT) (＜1.0 mm), group Ⅱ: 50 patients with thickened carotid IMT (1.0 mm ≤ IMT ＜1.5 mm) and group Ⅲ: 50 patients with carotid IMT ≥ 1.5 mm.Another 50 healthy physical examinees during the same period were selected as controls. The general data, quantitative parameters of ufPWV technique, including pulse wave velocity at the beginning of systole (PWV-BS), pulse wave velocity at the end of systole (PWV-ES), and the measurement of Gal-3 and IL-33 were compared. Gal-3 and IL-33 were detected, to evaluate the diagnostic value of quantitative parameters of ufPWV technique and serum Gal-3 and IL-33 levels for metabolic syndrome. In addition, the correlation between quantitative parameters of ufPWV technique and serum Gal-3 and IL-33 levels, and the correlation of quantitative parameters of ufPWV technique and serum Gal-3 and IL-33 levels with carotid IMT were analyzed. The impact of quantitative parameters of ufPWV technique, Gal-3 and IL-33 on the risk of carotid atherosclerotic plaque (CAP) was analyzed. 
Results Heart rate, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL-C) and low-density lipoprotein (LDL-C) were higher in the observation group than in the control group (P＜0.05).The quantitative parameters of ufPWV technique, including PWV-BS and PWV-ES, and serum Gal-3 and IL-33 levels were higher in the observation group than in the control group (P＜0.05). The quantitative parameters of ufPWV technique, including PWV-BS, PWV-ES, and serum Gal-3 and IL-33 levels were lower in group Ⅰ than in group Ⅱ, and lower in group Ⅱ than in group Ⅲ (P＜0.05). The area under the receiver operating characteristic (ROC) curve (AUC) of quantitative parameters of ufPWV technique and serum Gal-3 and IL-33 levels for the diagnosis of metabolic syndrome was 0.836, 0.802, 0.818 and 0.823, respectively, and the AUC for the combined diagnosis was 0.901, which was significantly higher than the diagnostic value of each index alone; The quantitative parameters of ufPWV technique,including PWV-BS and PWV-ES had a positive correlation with serum Gal-3 and IL-33 levels, and the quantitative parameters of ufPWV technique, PWV-BS and PWV-ES, as well as serum Gal-3 and IL-33 levels, were positively correlated with carotid IMT (P＜0.05). The risk of CAP development was 2.490, 2.490, 2.698, and 2.212 times higher in those with high levels of the quantitative parameters of ufPWV technique, Gal-3, and IL-33, respectively, than in those with low levels. 
Conclusion In patients with metabolic syndrome,quantitative parameters of ufPWV technique, PWV-BS and PWV-ES, are positively correlated with serum Gal-3 and IL-33 levels, and their levels are related to the development of metabolic syndrome and atherosclerosis, which can indicate the occurrence of carotid plaque and provide a reference basis for clinical diagnosis and treatment. 

Key words: metabolic syndrome, carotid artery diseases, ultrafast pulse wave technique