In-stent Restenosis Of Coronary Artery Imaging Assessment And Mechanism Of Genetic Interference Inhibition

PARTⅠComparative study of Dual-source CT coronary angiography and X-ray coronary angiography in coronary artery stenosisObjective The aim of this study was to assess the diagnostic accuracy of dual-source computed tomography(DSCT) in the evaluation of coronary artery disease(CAD) compared with X-ray coronary angiography (CAG). Methods 47 cases of probability CAD(35 male,12 female, mean age 63.32±10.41 years,mean heart rate 76.2±14.8bpm)were carried out DSCT inspection without heart rate control. Multi-planar reconstruction(MPR), curved projection reconstruction(CPR), maximum intensity projection(MIP) and volume rendering techniques(VRT) reconstruction of DSCT data were performed respectively. CAG was served as the standard of reference and was performed within two weeks after the DSCT coronary angiography. All DSCT and CAG data sets were double-blindly evaluated by 2 observers. Results In all of the DSCT angiography images , 94.98%(625/658) segments could be evaluated compared with SCA images. 95.52%(597/625) segments were good image quality. Without heart rate control, the diagnostic sensitivity, specificity, positive predictive value and negative predictive value of DSCT evaluating coronary artery stenosis were 91.8%,97.7%,94.3%,97.5%, respectively. The diagnostic sensitivity and specificity were more than 95% in the left main coronary artery, left anterior descending(LAD) and right coronary artery(RCA), respectively. But the diagnostic sensitivity of the diagonal branch, the branch of left circumflex coronary artery(LCX) and distal RCA branches were only 86%,71.4%,76.9%, respectively. Conclusions DSCT coronary artery angiography could be used as a reliable method in the diagnosis of CAD without heart rate control. DSCT could be widely used in screening patients with CAD, the preoperative evaluation and postoperative follow-up of coronary artery surgery/stent implantation.PARTⅡDual-source CT coronary angiography assessment in stent restenosis of coronary arteryObjective The aim of this study was to assess the diagnostic accuracy of dual-source computed tomography(DSCT) in the evaluation of coronary artery in-stent restenosis(ISR) compared with coronary angiography (CAG). Methods 62 cases,implanted 117 stents,carried out inspection DSCT with heart rate control(<75bm). In all cases checking stent the axial view images,multi-planar reconstruction(MPR), curved projection reconstruction (CPR), maximum intensity projection(MIP) and volume rendering techniques (VRT) reconstruction of DSCT data were respectively performed. CAG was served as the standard of reference and was performed within two weeks after the DSCT coronary angiography. All DSCT and CAG data sets were double-blindly evaluated by 2 observers. Results In all of the DSCT angiography images,86.3%(101/117) stentss could be evaluated compared with CAG images. Twelve of 16 stents with ISR were correctly diagnosed by DSCT. With heart rate control, the diagnostic sensitivity, specificity, positive predictive value and negative predictive value of DSCT evaluating coronary artery ISR were 80%,95.3%,85.7%,96.4%, respectively. In all stents, the diameter≥3.5mm were assessable, but the diameter≤2.75mm was not good. Conclusions DSCT may be useful to detect in-stent restenosis with heart rate control, especially in stents with a relatively large diameter.PARTⅢEffect of RNA interference inhibition endothelial cells of IL-6 expression on vascular smooth muscle cells migrationObjective To investigate the effects of interference endothelial cells(EC) expression IL-6 by siRNA on the migration of smooth muscle cells(SMC),in the co-culture model which ECs were seeded on the lower chamber and SMCs on the upper chamber. Methods The time gradient and concentration gradient of the IL-6 mRNA expression, which were stimulated to EA.HY926 cells by lipopolysaccharide(LPS), were detected by RT-PCR. The small hairpin RNA(shRNA) eukaryotic expression vector targeting IL-6 gene, named pGensil-1.1-IL-6, was constructed and transfected into EA.HY926 cells by lipofectamine 2000 for intervention IL-6 expression. The inhibition effects on IL-6 gene determined by RT-PCR and ELISA. In co-cultue system, the MMP-9 mRNA and MMP-9 protein, expressed by human vascular smooth muscle cells(HUVSMC), were detected by RT-PCR and Western Blot respectively. Then the HUVSMC were stained by viola crystalline and the migration number of HUVSMC was detected. Results The highest IL-6 mRNA expression was stimulated EA.HY926 cells by 100mg/L LPS in 8-hour. The IL-6.1siRNA interference group stimulation EA.HY926 cells IL-6 expression was decreased 60% compared with LPS group (152±16.3/372±37.8pg / mL, P <0.01). Comparing with LPS stimulation EA.HY926 cells group in co-culture model, the HUVSMC expression of MMP-9mRNA and protein in siRNA interference EA.HY926 cells group was decreased. The number of cells migration was reduced too. Conclusions MMP-9 expression in SMC were reduced, by inhibition EC IL-6 expression with siRNA, and then weakening the ability of smooth muscle cells to migrate. The aim to IL-6 gene interference therapy probably will be a new way of inhibition in-stent restenosis.