[Quantitative ultrasonic integrated backscatter of the intima-media complex, serum level of matrix metalloprotease-9 and simvastatin in hyperlipemia patients].

Objective: To determine the diagnostic value of the integrated backscatter (IBS) technique for carotid artery atherosclerosis (AS), to investigate the correlation between IBS of carotid artery and the serum level of matrix metalloprotease-9(MMP-9), and to explore the effect of simvastatin on the IBS value of the carotid artery and serum MMP-9 level in hyperlipemia patients.

Methods: Fifty-eight patients with hyperlipemia and 26 normal controls were enrolled in this study. Patients with hyperlipemia were randomly divided into 2 groups: a simvastatin treatment group (20 mg/d) and a control group (without simvastatin treatment). Twenty-six healthy people were served as normal control group(n=26).The corrected IBS values(C-IBS) in carotid arteries,the intima-media thickness (IMT), and the serum MMP-9 levels were measured in the normal control group and the patients with hyperlipemia before and 8 weeks after the simvastatin therapy.

Results: The C-IBS of the simvastatin treatment group and the control group was significantly lower than that in the normal control group (all P<0.05). The IMT and MMP-9 in the simvastatin treatment group and the control group were significantly higher than those in the normal control group (all P<0.05). There was a negative correlation between the C-IBS of carotid arteries and the serum MMP-9 levels in the patients with hyperlipemia (r=-0.76,P<0.05). Eight weeks after the simvastatin treatment, the serum MMP-9 levels decreased significantly(P<0.05).

Conclusion: There is a negative correlation between the decreased C-IBS of carotid arteries and the increased serum MMP-9 levels in patients with hyperlipemia.The decreased C-IBS of carotid arteries and the increased serum MMP-9 levels may be the early indicators of atherosclerosis in hyperlipemia patients. The anti-atherosclerosis effect of simvastatin may partly attribute to its ability to lower the serum MMP-9.