Abstract: AIM: To evaluate the effects of medium dosage atorvastatin on coronary plaque recession and its components using IVUS gray-scale and virtual histology analysis.METHODS: 22 patients who had been preliminarily clinically diagnosed as coronary heart disease were performed coronary angiography.The selected patients must have at least one major coronary branch whose stenosis extent was 20 %-50 % by CAG examination with eye-measurement.The grayscale and virtual histology after selecting the stenosis aeteria coronaria as target vessel were recorded and the target blood vessel were examined by IVUS.All selected patients were treated with 20 mg atorvastatin lasting for 6 months after the performance and after 6 months the reexamination of the vessel by CAG and IVUS were performed.The LDL-C levels of patients before and after the treatment were compared ;meanwhile the target vessel MLD and DS variation using quantitative coronary angiography were analyzed.The plaque volume and composition variation using IVUS were also analyzed.RESULTS: After 6 months, the LDL-C level was decreased significantly from (3.48±0.49 )mmol/L to (2.25±0.32) mmol/L.The mean decreasing level was 1.23 mmol L and the level diminished 35.3 %(P<0.05) compared with the baseline.The volume of plaque was decreased from (362±167) mm3 to (314±136) mm3.It was decreased by 48.2 mm3 and compared with the baseline it diminished 13.3 % (P<0.05).The proportion of fiber was increased from 66.7 %±5.8 % to 69.8 %±4.4 % (P< 0.05) , and the proportion of necrosis core was decreased from 12.9 %±5.8 %to 9.8 %±4.2 % (P<0.05).The decreasing level of plaque volume was related to the LDL-C decreasing level (r=0.54, P<0.05) , not the proportion of necrosis core ecreasing level was related to the LDL-C decreasing level (r=0.07,P>0.05).CONCLUSION: Patients with mild coronary artery lesions were treated with medium dosage of atorvastatin for 6 months, the plaque recessed, the proportion of fiber increased and the proportion of necrosis core decreased, moreover, the plaque volume decreasing level was related to the LDL-C decreasing level.

Key words: atorvastatin, plaque, intravascular ultrasound, low density lipoprotein cholesterol