【Abstract】 Objective To reduce restenosis in vein grafts after coronary artery bypass grafting, to investigate theeffect of human tissue factor pathway inhibitor(TFPI) gene del ivery on neointima formation. Methods The eukaryotic expressed plasmid vector pCMV-(Kozak) TFPI was constructed. Forty-eight Japanese white rabbits were randomly divided into 3 groups with 16 rabbits in each group: TFPI group, empty plasmid control group and empty control group. Animal model of common carotid artery bypass grafting was constructed. Before anastomosis, vein endothel iocytes were transfected with cationic l iposome containing the plasmid pCMV- (Kozak) TFPI (400 μg) by pressurizing infusion (30 min) in TFPI group. In empty plasmid control group, vector pCMV- (Kozak) TFPI was replaced by empty plasmid pCMV (400 μg). In empty control group, those endothel iocytes were not interfered. After operation, vein grafts were harvested at 3 days for immunohistochemical, RTPCR and Western-blot analyses of exogenous gene expression and at 30 days for histopathology measurement of intimal areas, media areas and calculation of intimal/media areas ratio. Luminal diameter and vessel wall thickness were also measured byvessel Doppler ultrasonography and cellular category of neointima was analyzed by transmission electron microscope at 30 days after operation. Results Human TFPI mRNA and protein were detected in TFPI group. The mean luminal diameter of the TFPI group, empty plasmid control group and empty control group was (2.68 ± 0.32) mm, (2.41 ± 0.23) mm and (2.38 ± 0.21) mm respectively. There were statistically significant differences between TFPI group and control groups (P lt; 0.05). The vessel wall thickness of the TFPI group, empty plasmid control group and empty control group was (1.09 ± 0.11) mm, (1.28 ± 0.16) mm and (1.34 ± 0.14) mm respectively. There were statistically significant differences between TFPI group and other control groups (P lt; 0.01). The mean intimal areas, the ratio of the intimal/media areas of the TFPI group were (0.62 ± 0.05) mm2and 0.51 ± 0.08 respectively, which were reduced compared with those of the two control groups(P lt; 0.05). The mean media areas had no significant differences among three groups (P gt; 0.05). Through transmission electron microscope analyses, no smoothmuscle cells were seen in neointima of TFPI group in many visual fields, but smooth muscle cells were found in neointima of two control groups. Conclusion Human TFPI gene transfection reduced intimal thickness in vein grafts.
ObjectiveTo analyze the effectiveness of in vitro fenestration versus bypass surgery techniques in the treatment of type B aortic dissection involving the left subclavian artery by thoracic endovascular aortic repair (TEVAR).MethodsAmong the 53 patients with type B aortic dissection involving the left subclavian artery admitted to our center from January 2017 to October 2020, 23 underwent in vitro fenestration + TEVAR (a fenestration group with 18 males and 5 females aged 53.6±5.3 years), and 30 patients underwent left common carotid artery-left subclavian artery bypass + TEVAR (a bypass group with 24 males and 6 females aged 51.8±3.8 years). The effectiveness and safety between the two groups were compared.ResultsThe surgical success rate was 100.0% in both groups. And there was no death within postoperative 30 days and during the follow-up. There was no endoleak immediately postoperatively and during 1-year follow-up in the two groups. The operation time and hospitalization expenses in the fenestration group was less or shorter than those in the bypass group (P<0.05). The reduction in blood pressure of the left upper limb in the fenestration group was greater than that in the bypass group (P<0.05). There was no symptom of left upper limb ischemia, dizziness or hoarseness in both groups.ConclusionThe two methods of reconstruction of the left subclavian artery are safe and effective. In vitro fenestration can reduce surgical trauma and costs, and bypass surgery can provide better forward blood flow for the left subclavian artery.