Study of preventing venous graft restenosis by local application of simvastatin and mechanical preconditioning / 中国胸心血管外科临床杂志

@#Objective    To investigate the effect of simvastatin and mechanical pretreatment on intimal hyperplasia of venous graft and its mechanism. Methods    Twelve New Zealand rabbits were selected and randomly divided into 4 groups: a blank control group, a simvastatin topical treatment group, a mechanical precondition group and a combined group (n=3 in each group). Ultrasound was used to evaluate the changes of graft wall and blood flow velocity in the graft, and pathological section was used to evaluate the intimal hyperplasia. Human umbilical cord endodermal cells were cultured in vitro. A simvastatin group and a solvent control group were set to detect YAP phosphorylation, downstream target gene expression and cell proliferation. Results    Vascular ultrasound showed that except the simvastatin topical treatment group, the flow velocity in vein grafts in the other three groups significantly increased 21 days after surgery compared with 7 days after surgery (P<0.01). Pathological sections showed that the thickness of new intima in the simvastatin topical treatment group, mechanical precondition group, combined group and blank control group were 45.56±4.11 μm, 201.28±16.71 μm, 143.57±7.82 μm, 249.45±13.33 μm, respectively, and there were statistical differences compared with the blank control group (P<0.05). In vitro results showed that compared with the solvent control group, cell death was observed in high concentration simvastatin (5 mmol/L) group, cell proliferation was inhibited in low concentration simvastatin (2.5 mmol/L) group (P<0.05), the expression of YAP protein in the simvastatin group was unchanged, but the expression of phosphorylated YAP protein significantly increased (P<0.05), and the expression of downstream target gene ccn1 was down-regulated (P<0.001). Conclusion    Intravascular local application of simvastatin and mechanical preconditioning alone or in combination can inhibit intimal hyperplasia of venous graft. High concentration of simvastatin has cytotoxicity, while low concentration of simvastatin has inhibitory effect on cell proliferation. Simvastatin can inhibit the formation of new intima by inhibiting the entry of YAP into the nucleus and reducing the transcription of cell proliferation-related target gene ccn1.

The role of vein grafts in reconstructive head and neck microsurgery

Abstract Objective: Free tissue transfer is widely used for head and neck reconstruction. In certain circumstances, vein grafting is required to elongate free flap pedicles to connect them to appropriate recipient vessels. Because of controversy regarding the use of interposition vein grafts in free tissue reconstruction, this paper reports vein graft indications, techniques, safety, and outcomes for head and neck microvascular surgery. Methods: Twenty-six patients (23 men and 3 women) who underwent interposition vein grafting concurrent with free tissue transfer were included in this study. The most common reason for head and neck reconstruction with vein graft was tumor recurrence, followed by flap salvage. The interposition vein grafts were applied in two manners as temporary arteriovenous (A-V) loop and conduit to extend the length of the free flap for venous drainage. Results: The most common reconstructions were anterolateral thigh flaps (15 cases), followed by vastus lateralis myocutaneous (3 cases) and radial forearm (2 cases) flaps. The common recipient vessels were superior thyroid artery, superficial temporal artery and external jugular vein. The free flap loss rate was 7.7% with vein grafts and 4.9 without vein grafts (p = 0.380). The free flap complication rate was 50.0% and 16.8% in patients with and without vein grafts, respectively (p < 0.001). Radiation therapy, chemotherapy, prior neck dissection, and prior free flap transfer were more common in the vein graft group (all p < 0.001). The hospital stay was significantly longer for the vein graft group than for the non-vein graft group (29.5 vs. 19.0 days; p = 0.001). Conclusion: Overall free flap survival rates of 92.3% and 95.1% in the vein and non-vein graft groups, respectively - indicating the reliability of the vein grafts in challenging head and neck reconstructions, particularly in salvage cases and patients with multiple reconstructions. Level of evidence: Level 3.

Insights into the clinical studies related to cardiovascular surgery from the American Heart Association’s Scientific Sessions 2021: Part one / 中国胸心血管外科临床杂志

@#In the American Heart Association’s Scientific Sessions 2021, the results of six clinical trials related to cardiovascular surgery were revealed. The PALACS trial demonstrated that posterior left pericardiotomy during open heart surgery was associated with a significant reduction in postoperative atrial fibrillation; the EPICCURE study found that injection of mRNA encoding vascular endothelial growth factor (VEGF-A mRNA) directly into the myocardium of patients undergoing elective coronary artery bypass grafting (CABG) improved patients’ heart function; the VEST trial once again proved the safety and potential value of external stent for vein graft. This article will interpret the above-mentioned three studies.

Morphological Changes in Endothelial Cell Organelles in a No-Touch Saphenous Vein Graft

ABSTRACT Introduction: Improved long-term patency of the no-touch (NT) saphenous vein graft has been reported to result from the preservation of a healthy vascular microstructure, especially endothelial cells. However, the precise morphology of endothelial cells and their organelles in NT saphenous vein graft has not been fully investigated. In this study, we assessed the ultrastructure of preserved endothelial cells in saphenous vein graft using transmission electron microscopy. Methods: Intact control (IC) vein, NT saphenous vein graft, and conventional (CT) saphenous vein graft were harvested from a patient. After observation by light microscopy, the nuclei and mitochondria in the preserved endothelial cells were compared among IC, NT, and CT using transmission electron microscopy, and the endothelial organelles were assessed quantitatively. Results: Light microscopy showed that the preservation of endothelial cells was comparable in IC, NT, and CT. Subsequent transmission electron microscopy observation showed that the nuclei in preserved endothelial cells appeared more swollen in CT than that in NT. Quantitative analysis revealed that nuclear size and circularity of preserved endothelial cells in NT and IC were similar, but those in CT were larger and higher, respectively, than those in IC and NT. In addition, the mitochondrial size in preserved endothelial cells in CT was larger than that in IC and NT. Conclusion: Necrotic changes in endothelial organelles characterized by swelling of nuclei and mitochondria were prominent in CT saphenous vein graft. The normally maintained ultrastructure of preserved endothelial cells in NT saphenous vein graft could contribute to long-term patency.

Association between SYNTAX II Score and late saphenous vein graft failure in patients undergoing isolated coronary artery bypass graft surgery

SUMMARY OBJECTIVE: Coronary artery bypass graft (CABG) surgery is a well-established treatment modality for patients with multivessel coronary artery disease (CAD). Syntax II Score has been established as novel scoring system with better prediction of postprocedural outcomes. This study aimed to investigate the prognostic value of SYNTAX II Score for predicting late saphenous vein graft (SVG) failure in patients undergoing isolated CABG. METHODS: The records of 1,875 consecutive patients who underwent isolated CABG with at least one SVG were investigated. Those who underwent coronary angiography and SVGs angiography at least 1 year after the CABG were included. Patients were divided into two groups based on the presence or absence of SVG failure. For each group, predictors of late SVG failure and subsequent clinical outcomes were analyzed. RESULTS: According to this study, the presence of hypertension, higher rates of repeat revascularization, and higher SYNTAX II Scores were found to be independent predictors of late SVG failure. In addition, the prognostic value of SYNTAX II Score was found to be significantly higher than anatomical SYNTAX Score in terms of predicting late SVG failure and major adverse cardiovascular and cerebrovascular event. CONCLUSIONS: There was a strong association between SYNTAX II Score and late SVG failure in patients undergoing isolated CABG.

Revascularización de arteria humeral con vena safena invertida, en traumatismo vascular por arma blanca / Revascularization of the humeral artery with a vein saphenous inverted in vascular trauma by stabbing

Introducción: Los traumatismos vasculares de los miembros son muy frecuentes en la actualidad, cuando no reciben la atención requerida, pueden evolucionar a complicaciones graves: pérdida del miembro y muerte del paciente. Objetivo: Describir la técnica de reparación de la arteria humeral mediante el uso de vena safena, en un caso con traumatismo de la arteria humeral, con compromiso vascular. Caso clínico: Paciente de 37 años de edad con antecedentes de enfermedad psiquiátrica, con diagnóstico de herida por arma blanca con compromiso vascular en antebrazo izquierdo, de cuatro horas de evolución. Al ingreso se encontraba inestable, con choque hipovolémico, miembro cianótico y ausencia de pulsos distales. Se indicó, por vía parenteral, antibióticos, soluciones cristaloides y sangre. En el quirófano se encontró sección de total de la arteria humeral, se realizó revascularización con injerto de vena safena invertida. El paciente evolucionó favorablemente y egresó al tercer día. Once meses después se realizó ecografía dópler y se constató buena permeabilidad del injerto. Conclusiones: La técnica de revascularización con vena safena invertida contribuyó de forma satisfactoria en la supervivencia y calidad de vida del paciente tratado (AU)

Introduction: The vascular traumatisms of the limbs are very frequent at present. When these injuries do not receive the required care they can evolve to serious complications, which includes the loss of the limb or death. Objective: To describe the brachial artery repair technique using the saphenous vein in a case with brachial artery trauma with vascular compromise. Clinical case: 37-year-old patient with a history of psychiatric illness, with a diagnosis of a stab wound with vascular compromise in the left forearm of four hours of evolution. On admission, he was unstable, hypovolemic shock, with cyanotic limb and absence of distal pulses. Intravenous antibiotics, crystalloid solution and blood were indicated. The patient was transferred to the surgery and a total section of the brachial artery was found. The revascularization technique was performed with an inverted saphenous vein graft. The patient evolved favorably and was discharged on the third day. Eleven months later, Doppler ultrasound was performed and good graft patency was confirmed. Conclusions: The inverted saphenous vein revascularization technique contributed satisfactorily to the survival and quality of life of the treated case(AU)

Experimental study of adventitial collagen cross-linking by glutaraldehyde reducing intimal hyperplasia of vein graft / 中华胸心血管外科杂志

Objective:To evaluate the validity of adventitial collagen cross-linking by glutaraldehyde(GA) to reduce intimal hyperplasia of vein graft in a rabbit carotid artery bypass graft model.Methods:Harvesting 36 segments of the external jugular vein and 6 segments of the internal carotid artery with 3 cm length from the New Zealand white rabbits. The veins were randomly divided into 6 groups and underwent adventitial collagen cross-linking by 0.3% glutaraldehyde for 0 min, 1 min, 2 min, 3 min, 4 min, and 5 min, respectively. All vessel segments were subjected to biomechanical tests and pathological tests. Carotid artery bypass graft models were established in 24 New Zealand white rabbits including crosslinked group(n=12) and non-crosslinked group(n=12). The vein grafts were obtained for pathological examination 4 weeks after models feeding, and the intimal hyperplasia of vein graft was evaluated.Results:Adventitial cross-linking increased fiber density of adventitia significantly, and increased the stiffness of the veins as the time of cross-linking increased. And in the high strain region(strain ratio 1.4-1.8), the mechanical curve of veins receiving 3min cross-linking was similar to that of the carotid artery. The patent rate of the vein grafts of rabbit models was 100% after 4 weeks. Comparing with non-crosslinked group, the intimal and medial thickness of vein grafts in crosslinked group were reduced remarkably[(78.83±9.02)μm vs.(140.19±19.90)μm, (43.75±5.05)μm vs.(58.35 ± 8.61) μm, P<0.01). Conclusion:Adventitial collagen cross-linking by GA can enhance the mechanical strength of the jugular vein, and reduce the intimal hyperplasia of the jugular vein grafts in rabbit models.

Functional role and underlying mechanisms of neuropilin-1 in proliferation and migration of rat vascular smooth muscle cells / 中国胸心血管外科临床杂志

@#Objective    To investigate the role and potential mechanisms of neuropilin-1 (NRP1) in the pathogenesis of vein graft failure. Methods    The rat vascular smooth muscle cells (VSMCs) were transfected with NRP1-shRNA adenovirus and negative control adenovirus respectively. Cell counting kit-8, flow cytometry, Transwell and Western blot were used to investigate the effects of inhibition of NRP1 on VSMCs proliferation viability, apoptosis, migration capacity and its downstream signaling pathway protein expression. Results    The proliferation and migration of rat VSMCs could be inhibited after down-regulation of NRP1, and the increase of apoptosis was also observed. Moreover, inhibition of NRP1 significantly reduced Akt and NF-κB phosphorylation in rat VSMCs, but had little effect on activation of ERK1/2. Conclusion    NRP1 may promote vein graft hyperplastic remodeling by regulating the proliferation and migration of VSMCs through PI3K/Akt and NF-κB pathways, but further animal study is required.

Management of extensive nerve gaps of more than 5 cm by vein graft in three cases

The aim of this study was to evaluate the effectiveness of use of extensive vein grafts to manage nerve gap repair. The study on peripheral nerve injury has been carried out in this country as well as abroad for many years, but the use of veins as the conduit is more than three decades old and still in evolving phase for standard clinical procedure. Its application is simple and regeneration of nerve is quite satisfactory specially for nerve gap of less than 5 cm. However, the present study was done on extensive nerve gaps of more than 5 cm to 10 cm gaps specially of after long duration of injury to see the results. Inspite of poor results due to extensive nerve gap and treatment tried after long duration of injury, it is quite encouraging to see nerve growth in biopsy of one venous tube and it is great achievement for future study. As of now any vein tube applied for nerve gap of more than five cm is not successful. So successful use of venous tubes is still in infancy for nerve gap of more than 5 cm.

Numerical study on the mechanical coupling of external vascular stent and vein graft in coronary artery bypass surgery / 生物医学工程学杂志

External support stent is a potential means for restricting the deformation and reducing wall stress of the vein graft, thereby improving the long-term patency of the graft in coronary artery bypass surgery. However, there still lacks a theoretical reference for choosing the size of stent based on the diameter of graft. Taking the VEST (venous external support) stent currently used in the clinical practice as the object of study, we constructed three models of VEST stents with different diameters and coupled them respectively to a model of the great saphenous vein graft, and numerically simulated the expansion-contraction process of the vein graft under the constraint of the stents to quantitatively evaluate the influence of stent size on the radial deformation and wall stress of the vein graft. The results showed that while the stent with a small diameter had a high restrictive effect in comparison with larger stents, it led to more severe concentration of wall stress and sharper changes in radial deformation along the axis of the graft, which may have adverse influence on the graft. In order to solve the aforementioned problems, we ameliorated the design of the stent by means of changing the cross-sectional shape of the thick and thin alloy wires from circle into rectangle and square, respectively, while keeping the cross-sectional areas of alloy wires and stent topology unchanged. Further numerical simulations demonstrated that the ameliorated stent evidently reduced the degrees of wall stress concentration and abrupt changes in radial deformation, which may help improve the biomechanical environment of the graft while maintaining the restrictive role of the stent.

Intravenous transplantation of olfactory ensheathing cells at different time points for repairing spinal cord injury / 中国组织工程研究

BACKGROUND: Olfactory ensheathing cells promote axonal regeneration, provide nutritional support for the injured host cells and regulate inflammation reaction, which possess potential for spinal cord injury repair. OBJECTIVE: To explore the optimal time window for intravenous transplantation of olfactory ensheathing cells in the treatment of spinal cord injury. METHODS: Thirty male SPF level rats were used to establish the rat models of spinal cord injury by spinal cord hemisection. Rat models were then randomly divided into five groups: 1-, 3-, 7-and 10-day olfactory ensheathing cell transplantation and PBS groups. Olfactory ensheathing cells were labeled with fluorescent quantum dots. PBS was injected into the rats in the PBS group after spinal cord injury. The injured spinal cord was removed at 1 day after injection. A small animal imager was used to measure the fluorescence transferred to the lesion at different time points. The number of cells transferred to the lesion was measured based on the intensity of fluorescence. The Anti-p75 NGF Receptor antibody was used for immunohistochemistry detection of the injured spinal cord. The study was approved by the Ethics Committee of Animal Laboratory of Ningxia Medical University, No. 2017-073. RESULTS AND CONCLUSION: Fluorescent quantum dots could label olfactory ensheathing cells. Results of fluorescence assay and immunohistochemistry indicated that transplanted olfactory ensheathing cells were transferred to the lesion at 1, 3, 7 and 10 days. Most cells were transferred to the lesion at 7 days. Therefore, these results indicate that olfactory ensheathing cells transplanted at different time points after spinal cord injury can be transferred to the lesion, with a number peak at 7 days that is the best time window for cell transplantation.

Research progression of coronary artery bypass grafting and perioperative secondary prevention / 医学研究生学报

Coronary artery bypass grafting (CABG) has been a standard revascularization method for three-vessel disease and left main coronary artery disease since its development in the 1950s. In recent years, with the development of basic research, clinical diagnosis, surgical instruments, and interdisciplinary work, significant progress has been made in the surgical approaches, saphenous vein graft harvesting, and secondary prevention during the perioperative period. This article reviews the surgical methods of coronary artery bypass grafting, the development status and hot issues of perioperative secondary prevention.

Vein graft bridged free flap for lower extremity trauma reconstruction / 中华整形外科杂志

Objective@#To investigate the efficacy and the technical details of utilizing a long segment of vein graft to bridge the vascular defect when a free flap is used to repair extensive injuries in lower extremities.@*Methods@#For the reconstruction of extensive leg defect caused by serious composite injury, a local flap is unavailable or cannot fulfill the requirements. The main vessels of the leg could be damaged. It is challenging work to find an ideal recipient vessels for a free flap. The saphenous vein was harvested from the contralateral lower extremities and utilized to bridge the vascular gap between the recipient vessels and flap pedicle vessels. A latissimus dorsi myocutaneous or anterolateral thigh free flap was used to reconstruct the leg defect. The distal end of the grafted vein was anastomosed to the superficial femoral artery in an end-to-side fashion, and the proximal end to the artery of flap pedicle in an end-to-end fashion. When a vein insufficiency was present, the proximal and distal ends of the additional grafted vein were anastomosed to the recipient vein and vein of flap pedicle in an end-to-end fashion.@*Results@#From July 2010 to April 2019, 27 patients underwent reconstruction of leg using the above-mentioned method. There were 20 males and 7 females. The patients′ age ranged from 16 to 54 years with an average of 30.6 years. There were 19 latissimus dorsi myocutaneous flaps and eight anterolateral thigh flaps. The grafted saphenous vein was used to bridge the arterial gap in 21 cases and to bridge both the arterial and venous gaps in 6 cases. The length of the grafted vein for arterial and venous defects was ranged from 14 cm to 43 cm (mean, 24.8 cm) and 5 cm to 12 cm (mean, 8.6 cm), respectively. 26 flaps completely survived after surgery. Venous congestion occurred in the remaining one flap and the flap eventually lost. The patient eventually opted for amputation. All patients were followed up for 3 to 14 months with an average of 9 months. Functional and aesthetic outcomes were obtained in both the recipient and donor sites. No obvious edema of lower extremities was observed.@*Conclusions@#For patients with a severe and large soft-tissue defect of the leg, fining an ideal recipient vessels for a free flap is crucial for a successful reconstructive surgery. It is a reliable and an additional option to choose the superficial femoral artery and/ or saphenous vein as the recipient vessels by using the grafted vein to bridge the vascular gaps.

Exceso de mortalidad no cardíaca en pacientes sometidos a angioplastía de puentes coronarios / Excess non cardiac mortality in patients undergoing PCI of venous coronary bypass grafts

Resumen: Introducción Las fallas de los puentes venosos pueden llegar casi al 50% a 10 años y la angioplastía percutánea es el tratamiento de elección. Estos pacientes constituyen un grupo de muy alto riesgo cardiovascular con tasas de mortalidad cercanas al 30% en el mediano plazo. Objetivo Caracterizar a la población sometida a angioplastia de puentes coronarios (APC) y comparar su mortalidad con un grupo pareado de pacientes intervenidos con Infarto agudo al miocardio con elevación del segmento ST (IAMCEST). Métodos Estudio retrospectivo de tipo Caso-Control que incluyó a pacientes con APC entre los años 2010-2016 comparados con igual número de controles con IAMCEST pareados por edad y sexo. Se analizaron características clínicas del procedimiento y mortalidad, tanto global como de causa cardiaca usando T Student, Chi2 y curvas de Kaplan Meier. Resultados Se identificaron 63 pacientes sometidos a APC (total 76 procedimientos). Los puentes más comúnmente intervenidos fueron a la arteria circunfleja 48,7%. Hubo 18 (28,5%) pacientes fallecidos en el grupo APC y 6 (9,5%) pacientes en el grupo con IAM-CEST, lo que resultó en un exceso de mortalidad global en pacientes con APC (HR 3,02; IC 95% 1,11 - 8,22, p=0,02). Esta diferencia se debió a una mayor mortalidad de causa no cardiaca en el grupo APC (12,7% (n=8) vs 3,2% (n= 2) [p=0,04]). Conclusión Los pacientes sometidos a APC presentan una mortalidad 3 veces mayor que aquellos pacientes con IAMCEST, principalmente derivada de una mayor mortalidad no cardíaca.

Abstract: Background Failure rates of saphenous vein grafts can reach almost 50% at 10 years and percutaneous angioplasty is the treatment of choice. This is a group with a very high cardiovascular risk, with mid-term mortality rates close to 30%. Aim To describe the population undergoing coronary bypass angioplasty (CBA) and compare their mortality with an age and gender matched group of patients with acute myocardial infarction with ST segment elevation (STEMI) Methods This was a retrospective case-control study including patients with CBA between 2010-2016. This group was compared with the same number of controls with STEMI matched by age and sex. Clinical characteristics, procedure variables and overall mortality as well as cardiac mortality were analyzed using Student's T test, Chi squared test and Kaplan Meier curves (significance set at p <0.05). Results: We identified 63 patients undergoing CBA (76 procedures). The most commonly intervened bypasses were to the circumflex artery (48.7%). There were 18 (28.5%) patients who died in the CBA group and 6 (9.5%) patients in the STEMI group, which resulted in an excess of global mortality risk in patients with CBA (HR 3.02, 95% CI 1.11 - 8.22, p = 0.02). This difference was driven by a higher non-cardiac mortality in the CBA group (12.7% (n = 8) vs 3.2% (n = 2) [p = 0.04]) Conclusion Patients undergoing CBA have a mortality rate more than three times that of the STEMI patients, mainly due to a higher non-cardiac mortality.

Expression and role of neutrophil gelatinase-associated lipocalin (NGAL) signaling pathways in the early stage of vein graft restenosis of a pig model / 中国胸心血管外科临床杂志

@#Objective     To investigate the expression of neutrophil gelatinase-associated lipocalin (NGAL) signaling pathways in the early stage of porcine vein graft restenosis, and to explore the possible role and mechanism in the early vein graft restenosis after coronary artery bypass surgery. Methods     We selected 18 ordinary healthy pigs weighing 25-30 kg and collected samples of the vein graft of pigs at the preoperation and postoperative days 7, 14 and 30. Hematoxylin-eosin (HE) staining and Masson staining, immunohistochemical method were used to observe the neointimal hyperplasia, the migration of smooth muscle cells and and vascular remodeling of the vein bypass graft. The expression changes of NGAL, matrix metalloprotenase (MMP)9, MMP2 and tissue inhibitor of metalloproteinase (TIMP)1 in different periods of the vein bypass graft was tested. Results     By HE and Masson staining, with the passing of modeling time, degradation of collagen matrix in the vein graft, gradually thickening of muscle fibers and the migration to the inner membrance and vascular remodeling caused the vascular stenosis. By immunohistochemistry, NGAL, MMP9  and MMP2 of normal vein in the model were seldom expressed and even did not express. At 14 days after the modeling, NGAL expression in the membrane layer of blood vessels began to appear, peaked at postoperative 30 days, and began to appear in the inner membrance. MMP9, MMP2 expression began to appear at postoperative 7 days, peaked at postoperative 14 days, and tended to decline at postoperative 30 days. TIMP1 expression was less in normal vascular walls and at the 14 days after the modeling, expression peaked in the vein graft. Conclusion     NGAL, MMP9, MMP2 and TIMP1 may be involved in the formation of early vascular graft restenosis. NGAL as initiator, results in the expression of MMP9 and MMP2, and participates in the degradation of collagen matrix and the migration of smooth muscle cells in vein grafts. TIMP1 as a negative factor, may play an important role in maintaining their own balance.

The comparison of clinical outcomes of the first and the second-generation drug-eluting stents implanted in vein grafts after coronary artery bypass graft / 天津医药

@#Objective To compare the clinical outcomes of the first and the second-generation drug-eluting stents (DES) implanted in saphenous vein grafts (SVG) in patients after coronary artery bypass graft (CABG). Methods A total of 108 patients with coronary angiography and DES implanting in SVG due to ischemia symptoms after CABG were collected in this study, including 69 patients with the first-generation of DES (drug-eluting: sirolimus) and 39 patients with the secondgeneration of DES (drug-eluting: zotarolimus or everolimus). The success rate of stents and mortality in hospital were compared between two groups of patients. The major adverse cardiac events (MACE), such as all-cause death, target vessel revascularization (TVR) and acute myocardial infarction (AMI) in 2-year follow-up were also compared between the two groups of patients. The survival curve was drawn by Kaplan-Meier method, and the MACE free survival rates of two groups of patients were compared. Cox regression analysis was used to evaluate the risk factors for MACE in patients with SVG stent implantation. Results There were no significant differences in the success rate of stents and mortality in hospital between the two groups. In average 2-year follow-up, a total of 37 cases of MACE were performed. There was no statistical difference in the incidence of MACE between the two groups (34.8% vs. 33.3%, P＞0.05). The proportion of TVR was significantly lower in the second-generation group than that of the first-generation group (13.0% vs. 2.6%, P＜0.05). Kaplan-Meier survival analysis showed that there were no statistically differences in the survival rates of no-cumulative events between the two groups (81.2% vs. 79.5%, Log-rank χ2=0.029, P＞0.05). COX regression analysis showed that diabetes (HR=2.530, 95% CI: 1.008-6.345, P=0.041) and stent diameter (HR=1.143, 95% CI: 1.043-1.253, P=0.004) were independent predictors for the MACE in patients implanted stents in SVG. Conclusion There are no significant differences in mortality in hospital and the MACE in 2-year follow-up between the patients of two generations of DES implanting in the SVG after coronary artery bypass grafting. The proportion of TVR is lower in the second-generation DES group. Patients with diabetes and large diameter stents have a poor prognosis.

Construction of the model of intimal hyperplasia in vein graft in New Zealand rabbit / 上海交通大学学报（医学版）

Objective • To establish New Zealand rabbit autogenous vein graft model and observe the changes of intimal hyperplasia in vein grafts at different time after grafting. Methods • 35 female New Zealand rabbits of 10 weeks old were randomly divided into 5 groups (7 rats in each group), i.e. postoperative 7 d group, postoperative 14 d group, postoperative 28 d group, postoperative 60 d group and normal control group. An animal model of external jugular vein common carotid artery bypass grafting was established, and the model construction steps were elaborated and optimized. Hematoxylin-eosin (H-E) staining was used to observe the intimal thickness after surgery and immunofluorescence staining was used to observe the expression of α-smooth muscle actin (α-SMA), which was one of the vascular smooth muscle cell (VSMC) differentiation marker protein. The effect of model construction was finally evaluated. Results • In addition to the normal control group, the other 28 New Zealand rabbits were successfully completed the vein graft operation. All the grafted veins kept unblocked except for one graft in postoperative 7 d group developed thrombosis, and the success rate was 96.4% (27/28). H-E staining and immunofluorescence staining showed significant intimal hyperplasia after vein grafting. Compared with the normal control group, the intimal thickness of the vein grafts was significantly increased (all P=0.000) and the fluorescence intensity of α-SMA was significantly enhanced at each time group after surgery. Conclusion • New Zealand rabbit vein graft intimal hyperplasia modeling has an ideal success rate and good repeatability, which provides an ideal experimental model for studying the mechanism and prevention of restenosis after vein grafting.

Inhibitory effects of resveratrol on the proliferation, migration and angiogenesis of HUVECs through targeting mTORC2/Rictor / 基础医学与临床

Objective To investigate the effect of resveratrol on the proliferation, migration and angiogenic ability of HUVECs mediated by Rictor over-expression adenovirus.Methods The Rictor was obtained through PCR and cloned into GV314 plasmid to construct recombinant plasmid, then co-transfected 293T cells with helper plasmids to obtain Rictor overexpressing adenoviral particles(Ad-Rictor),the vector without target gene Ad-Null was set as the negative control group.Ad-Rictor and Ad-Null were infected HUVECs respectively,we also set up blank control group and resveratrol-intervention group(Ad-Rictor+Res). The expression of recombinant protein was detected by fluorescence microscopy and Western blot. CCK-8 assay,wound healing and matrigel assay were performed to as-sess the proliferation,migration and tube formation of HUVECs. Results We constructed Ad-Rictor and Ad-Null which may infect HUVECs and express Rictor protein efficiently. Ad-Rictor could significantly improve the prolifer-ation,migration and lumen formation (P<0.05), resveratrol intervention may significantly inhibit these functions induced by Ad-Rictor (P<0.05). Conclusions Resveratrol inhibits the proliferation, migration and angiopoietic ability of HUVECs through targeting mTORC2/Rictor.

Mosaic adeno-associated virus-mediated gene transfer of calcitonin gene-related peptide for prevention of inflammatory mediator expression, macrophage infiltration and neointimal hyperplasia in an experimental rabbit vein graft model / 中国胸心血管外科临床杂志

@#Objective    To investigate the effect and mechanism of calcitonin gene-related peptide (CGRP) on the prevention and treatment of transplant vein graft disease. Methods    The 25 New Zealand white rabbits were divided into three groups: an experimental group [n=8, the rabbit jugular veins transfected with adeno-associated virus vector tipe 2/1 containing CGRP gene (AAV2/1-CGRP)], a carrier group [n=9, transfected with mosaic adeno-associated virus vector tipe 2/1 containing LacZ gene (AAV2/1-LacZ)] and a control group (n=8, saline) and then the cervical veins were implantated into the ipsilateral carotid artery by reverse end-side anastomosis. At 4 weeks after surgery, the pathology of the specimens, CD68 immunohistochemistry, in situ β-galactosidase staining were obtained. The expression of CGRP gene was detected by reverse transcription-polymerase chain reaction (RT-PCR). Monocyte chemoattractant protein-1(MCP- 1), tumour necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS) and matrix metalloproteinase-9 (MMP-9) were detected by real-time polymerase chain reaction (real-time PCR). Results    The CGRP and LacZ gene expression was positive at postoperative 4 weeks. The intima/media ratio was significantly inhibited in the experimental group. Macrophage infiltration and expression of inflammatory mediators including MCP-1, TNF-α, iNOS and MMP-9 were also significantly inhibited in the experimental group. Conclusion    Transfection of AAV2/1-CGRP inhibits inflammatory mediator expression, macrophage infiltration and neointimal hyperplasia in experimental vein graft disease.

Effects of intraoperative expansion on expression of stenosis-related genes in saphenous vein graft / 局解手术学杂志

Objective To investigate the effect of high pressure distention on the expression of stenosis-related genes of saphenous vein graft(SVG) during the coronary artery bypass grafting(CABG).Methods The biopsy specimens of saphenous vein collected from 10 patients who have undergone CABG,were divided into expansion group and no-expansion group.Real-time PCR and immunohistochemical staining were performed for examination of mRNA and protein expression of VE-cad,Egr-1,VCAN respectively.Student's t and Chi-square test were used to do statistic analysis.Results The results of RT-PCR showed that the mRNA transcription of Egr-1,VCAN in the expansion group were statistically significantly higher than those in no-expansion group(P<0.05).The mRNA transcription VE-cad in expansion group was statistically significantly lower than that in the no-expansion group(P<0.05).The immunohistochemical staining results showed that the expression of Egr-1 and VCAN in expansion group were significantly stronger than those in no-expansion group,while the expression of VE-cad was significantly lower than no-expansion group.Conclusion The intraoperative expansion of SVG can increase the expression of stenosis-related genes Egr-1 and Versican,and decrease the expression of stenosis-related gene VE-cad,which may be related with the SVG stenosis after CABG.