Effects of Coronary Artery Lesion Characteristics on Myocardial Ischemia / 医用生物力学

Objective To investigated the effect of stenosis characteristics (vascular elasticity and plaque properties) on myocardial ischemia. Methods An ideal geometric multi-scale coronary stenosis model based on fluid-structure interaction was established, and the fractional flow reserve (FFR) was simulated to evaluate myocardial ischemia. The effects of vascular elastic wall (elastic modulus of 1 MPa) and rigid wall, plaque types (lipid-rich plaque and calcified plaque) and plaque volume on myocardial ischemia were considered separately. Results The FFRCT simulation result of vessels with elastic wall was larger than that with rigid wall under all stenosis situations. The FFRCT of vessels in lipid-rich lesions was higher than that of calcified plaque (P=0.001). The trapezoidal plaque volume was larger than the cosine plaque volume, and the FFRCT of vessels in trapezoidal plaque was smaller than that of cosine plaque (P=0.001). Conclusions Vascular elasticity is a critical factor to simulate vascular hemodynamics. In moderate stenosis, calcified plaques are more likely to induce myocardial ischemia due to the larger luminal deformation and dilation of rich lipid plaque. When the stenosis is constant, the smaller the plaque volume, the higher the FFRCT and the smaller the possibility of myocardial ischemia.

Retrospective cohort study of early and mid-term results of HCR and MICS-CABG in coronary artery disease patients with low ejection fraction and non diabetes mellitus / 中华胸心血管外科杂志

Objective:To compare the early and mid-term results of hybrid coronary revascularization (HCR) and minimally invasive multivessel coronary artery bypass grafting (MICS-CABG) in coronary artery disease patients with low left ventricular ejection fraction and non diabetes mellitus, and to explore the indication of HCR and MICS-CABG.Methods:A retrospective cohort analysis of HCR and MICS-CABG cases with preoperative left ventricular ejection fraction less than 0.40, and without diabetes mellitus were conducted in Xijing Hospital from January 2015 to December 2019. 36 cases in HCR group and 17 cases in MICS group were included in this study. For HCR procedure, minimally invasive left internal mammary artery(LIMA) to the left anterior descending artery (LAD) bypass surgery were performed, and followed by percutaneous coronary intervention (PCI) to treat non LAD lesion 1 to 4 weeks later. MICS-CABG procedure was performed through left anterior small thoracotomy minimally invasive direct coronary artery bypass grafting for multiple diseased vessels.Results:The preoperative SYNTAX score in MICS group was significantly higher than that in HCR group ( P<0.05). There was no perioperative death in both groups. Troponin I, postoperative drainage volume, blood transfusion volume and ventilator ventilation time in MICS group were significantly higher than those in HCR group ( P<0.05). After 12 months follow-up, no patient died in both groups. Furthermore, all LIMA grafts were patency. The stenosis rate of drug-eluting stents in HCR group was similar to that of great saphenous vein grafts in MICS group. LVEF and left ventricular end diastolic diameter of both groups were significantly improved 12 months after operation ( P<0.05). Conclusion:HCR and MICS-CABG are minimally invasive and safe treatment for multivessel coronary artery disease patients with low ejection fraction and non diabetese mellitus. The early and mid-term therapeutic effects are satisfactory. If coronary artery lesions other than LAD are suitable for PCI, HCR should be the preferred treatment.

Preliminary report of preclinical trial of multi-genome engineering pig-to-macaque heart, liver and kidney transplantation / 器官移植

Objective To investigate the application prospect of the most extensive genome engineering pig internationally in preclinical xenotransplantation. Methods Porcine endogenous retrovirus (PERV) knockout combined with 3 major heterologous antigen gene knockouts and 9 humanized genes for inhibition of complement activation, regulation of coagulation disorders, anti-inflammatory and anti-phagocytosis were transferred into a pig (PERV-KO/3-KO/9-TG) as a donor, and the heart, liver and kidney were obtained and transplanted to 3 Rhesus macaque recipients respectively to establish a preclinical research model of pig-to-Rhesus macaque xenotransplantation. The functional status of xenografts after blood flow reconstruction was observed and the survival of recipients was summarized. The hemodynamics of xenografts were monitored. The change of hematological indexes of each recipient was compared. The histopathological manifestation of xenografts was observed. Results After the blood flow was reconstructed, all xenografts showed ruddy color, soft texture and good perfusion. The transplant heart, liver and kidney showed full arterial and venous blood flow and good perfusion at 1 d after operation. The postoperative survival time of heart, liver, and kidney transplant recipients was 7, 26, and 1 d, respectively. The levels of creatine kinase, creatine kinase isoenzyme, and lactate dehydrogenase increased in heart transplant recipient at 1 d after operation, and gradually recovered to near normal levels at 6 d after operation. All indexes increased sharply at 7 d after operation. The level of aspartate aminotransferase increased in liver transplant recipients at 2 d after operation, and the alanine aminotransferase basically returned to normal at 10 d after operation, but the total bilirubin continued to increase. Both aspartate aminotransferase and alanine aminotransferase increased at 12 d after operation, and reached a peak at 15 d after operation. The kidney transplant recipient developed mild proteinuria at 1 d after operation, and died of sudden severe arrhythmia. Histopathology showed that the tissue structure of cardiac and renal xenografts was close to normal, and liver xenografts presented with patchy necrosis, the liver tissue structure was disordered, accompanied by inflammatory damage, interstitial hemorrhage and thrombotic microangiopathy. Conclusions PERV-KO/3-KO/9-TG pig shows advantages in overcoming hyperacute rejection, mitigating humoral rejection and coagulation dysregulation. However, whether it can be used as potential donor for clinical xenotransplantation needs further evaluation.

Preliminary exploration of the domestic balloon-expandable valve in the treatment of degenerated tricuspid bioprosthetic valve via transcatheter "valve-in-valve" technology / 中国胸心血管外科临床杂志

@#Objective    To discuss the operation skill and clinical effects of using domestic balloon-expandable Prizvalve® transcatheter "valve-in-valve" to treat the degenerated bioprosthesis in the tricuspid position. Methods    All the admitted surgical tricuspid valve bioprosthetic valve replacement patients were evaluated by computerized tomography angiography (CTA), ultrasound, and 3D printing technology, and 2 patients with a degenerated bioprosthesis were selected for tricuspid valve "valve-in-valve" operation. Under general anesthesia, the retro-preset Prizvalve® system was implanted into degenerated tricuspid bioprosthesis via the femoral vein approach under the guidance of transesophageal echocardiographic and fluoroscopic guidance. Results    Transcatheter tricuspid valve implantation was successfully performed in both high-risk patients, and tricuspid regurgitation disappeared immediately. The operation time was 1.25 h and 2.43 h, respectively. There was no serious complication in both patients, and they were discharged from the hospital 7 days after the operation. Conclusion    The clinical effect of the degenerated tricuspid bioprosthetic valve implantation with domestic balloon-expandable valve via femoral vein approach "valve-in-valve" is good. Multimodality imaging and 3D printing technology can safely and effectively guide the implementation of this innovative technique.

The therapeutic effect and mid-term follow-up of 154 patients of multiple valvular surgery through right anterolateral intercostal thoracotomy: A retrospective cohort study / 中国胸心血管外科临床杂志

@#Objective    To investigate the therapeutic effect, safety and effectiveness of multiple valvular surgery through right anterolateral intercostal thoracotomy, as well as the mid-term follow-up results and surgeon's learning curve. Methods    The clinical data of 154 patients with multiple valvular disease were performed minimally invasive cardiac surgery in the Department of Cardiovascular Surgery, The First Affiliated Hospital of Air Force Medical University, from 2015 to 2019 were retrospectively analyzed. There were 103 males and 51 females, aged 23-68 years. Closed cardiopulmonary bypass was established through femoral artery and femoral vein, and the thoracic cavity was entered through a 6 cm transverse incision in the fourth intercostal space on the right side of sternum. Baseline and perioperative characteristics and postoperative outcomes were reviewed. Results    There was no perioperative death. The average cardiopulmonary bypass time was 159.3±39.4 min, and the aortic clamping time was 102.3±20.3 min. One patient underwent thoracotomy during the operation, and two patients underwent second thoracotomy for hemostasis. During the follow-up period of 10-55 months, 1 patient died, 2 patients developed mild perivalvular regurgitation, 6 patients developed moderate tricuspid regurgitation, and no serious cardiovascular events occurred in the rest of the patients. Conclusion    Our findings demonstrate that multiple valvular surgery through right anterolateral intercostal thoracotomy is safe, and in an acceptable risk of complication. The early and middle follow-up results are satisfactory. The minimally invasive cardiac surgery can also meet the requirements of cosmetology, and is conducive to the recovery of patients' mental and physical health. This method is worthy of application in medical centers with rich experience in routine cardiac surgery.

Interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma: A systematic review and meta-analysis / 中国胸心血管外科临床杂志

@#Objective    To evaluate the prognosis of interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma by single-arm meta-analysis. Methods    Related studies on treating retrograde Stanford type A aortic dissection and intramural hematoma with covered stent graft were retrieved from the databases by computer, including PubMed, EMbase, The Cochrane Library, Wanfang Data, VIP, CNKI and CBM, from inception to January 2020. Literatures were screened by researchers step by step according to the predefined inclusion and exclusion criteria. Quality of the enrolled literatures was evaluated, and data were extracted from the included studies. Afterwards, single-arm meta-analysis was carried out by the R3.6.3 software. Results    A total of 12 English and 5 Chinese studies were included, which were all case series, and the quality of all literatures was moderate evaluated by Newcastle-Ottawa Scale (NOS). After analyzing the clinical prognosis of 260 patients, the 30-day mortality was 6% (95%CI 0.04 to 0.11, P=0.97), the late mortality was 8% (95%CI 0.05 to 0.14, P=0.78), the incidence of endoleak was 21% (95%CI 0.16 to 0.29, P=0.06), the incidence of stroke was 5% (95%CI 0.03 to 0.09, P=0.99), the incidence of new aortic dissection was 7% (95%CI 0.04 to 0.11, P=0.96), the incidence of dissection progression was 10% (95%CI 0.07 to 0.16, P=0.24), and the absorption rate of intramural hematoma was 84% (95%CI 0.37 to 1.00, P<0.01). Conclusion    Interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma can obtain good early treatment results for some patients, and can be used as a safe and effective treatment for aged patient with high risk who cannot tolerate surgery. Endoleak, stroke and new aortic dissection are the early serious complications of this method.

Protective effect of growth differentiation factor 11 on myocardial injury in type II diabetic mice / 中国实验动物学报

Objective To observe the protective effect of growth differentiation factor 11(GDF11) on myocardial injury and the changes of myocardial apoptosis in type 2 diabetic C57BL/6J mice.Methods Sixty male C57BL/6J mice weighing 20-25 g were randomly divided into three groups: control group (control), type 2 diabetes mellitus group (DM) and GDF11 intervention group (DM + GDF11).To establish mouse model of type 2 diabetes, the mice were fed with high fat and high sugar diet for 4 weeks, and i.p.injected consecutively three times of streptozotocin (STZ) in a dose of 60 mg/kg.After the continuous high-fat and high-sugar diet for 4 weeks, the cardiac function was detected by small animal ultrasound, TUNEL staining was used to detect the apoptosis in myocardium, and the expressions of cleaved-caspase-3, Bcl-2, Bax were measured.Results Diabetic injury significantly reduced the left ventricular ejection fraction and left ventricular short axis shortening rate, and increased myocardial apoptosis.Recombinant GDF11 protein significantly improved cardiac function and reduced myocardial apoptosis.Conclusions Exogenous GDF11 can significantly reduce myocardial apoptosis and improve heart function after diabetic injury.

Clinical study of the appropriate range of warfarin anticoagulant therapy intensity in patients after heart valve replacement / 中国综合临床

Objective To explore the best range of international normalized ratio for anticoagulation treatment after mitral valve replacement (MVR) and double valve replacement (DVR).Methods We conducted a follow-up study involving 1592 patients who received the warfarin anticoagulant therapy after MVR or DVR in our hospital.Clinical data was collected including the admission information,the dose of warfarin and the INR level,and the occurrence of bleeding and thrombosis were recorded.The patients were divided into 2 (MVR and DVR) groups in terms of the different valve prostheses,and then each group was assigned to four subgroups according to their INR level ( A:INR=1.4-1.7;B:INR=1.7-2.0;C:INR=2.0-2.3;and D:INR=2.3-2.6) to compare the incidence of bleeding and thrombosis among these subgroups.Results The analysis of the incidence of bleeding:In MVR group,the subgroups with different INR levels had significant difference with participants with INR level at D having higher incidence of bleeding than the other 3 groups (Group A:x2=17.991,Group B:x2=13.436,Group C:x2=7.186;P＜0.01 ).We observed significant difference in DVR groups (x2=19.067,P＜0.01 ) with the increased incidence of bleeding of INR level at D compared with the other three groups ( Group A:x2=16.736,Group B:x2=10.486,Group C:x2=7.773;P＜0.01 ).The analysis of the occurrence of thrombosis;The groups of MVR and DVR had no significant differenceson in the incidences of thrombosis in all the levels of INR ( P ＞ 0.05 ).No significant statistical differences were found on the incidence of bleeding and thrombosis at INR level 1.4-2.3 ( P ＞ 0.05 ) Conclusion The present study suggestes that the level of INR at 1.4-2.3 is appropriate after the anticoagulation therapy in the MVR and DVR groups.

Influence of emergency PCI in different time windows to cardiac scar and cardiac function after myocardial infarction / 中国综合临床

Objective To observe the influence of emergency PCI in different time windows to cardiac scar and cardiac function after myocardial infarction. Methods One hundred and twenty-seven patients with acute myocardial infarction, who were treated in different time windows by emergency PCI, were enrolled into this study. The cases were divided into two groups according to the time when they took PCI after onset;group 3 hPCI included 66 patients had PCI at 3 h after onset and group 6 hPCI included 61 patients had PCI at 6 h. At 4th, 8th and 12th weeks, the fragmented QRS (fQRS) were observed by twelve synchronization cardiogram; ventricle wall movement strain rate were determined by cardiac speckle tracking imaging;left ventricular ejection fraction (LVEF)were measured by cardiac ultrasound to evaluate cardiac events and cardiac function after myocardial infarction. Results At 4th,8th and 12th weeks,the fQRS positive leads were significantly more in 6 hPCI group than 3 hPCI group ( P ＜ 0. 05 respectively ) . The ventricle wall movements strain rate and LVEF improved significantly in 3 hPCI group compared with 6 hPCI group (P ＜ 0. 05 ). Conclusions The earlier emergency PCI treatment was applied and the earlier the"criminal"blood vessels were opened ,the more ischemic myocardial cells were restored. Combination use of fQRS、 STI and LVEF examination could improve the diagnosis of cardiac scar formation and direct protective therapy.

Assessment of carotid atherosclerotic plaques using ultrasonographic elastography / 中华超声影像学杂志

Objective To evaluate the features of carotid atherosclerotic plaques on ultrasonographic elastography. Methods A total of 45 atherosclerotie plaques of the carotid artery in 33 patients were found with routine ultrasonography, all the 45 atherosclerotic plaques were divided into soft plaque, fibrous plaque, mixed plaque and calcified plaque. The elastograms of the plaques were oberseved and the strain contrast(stiffness ratio) of blood tissue in common carotid artery to plaques were calculated. Results Seventeen soft plaques, 15 mixed plaques and 13 calcified plaques were founded using routine ultrasonography, but 0 fibrous plaques were founded. The soft plaques were shown in green, the mixed plaques were showen as mosaic of green and blue and the calcified plaques were showen in blue by ultrasonographic elastography. The strain contrast in patients with calcified plaques and mixed plaques were significantly higher when compared with the soft plaques group(P 0. 001, P <0.05). The strain contrast in patients with calcified plaques was significantly higher than the mixed plaques group (P < 0.001). Conclusions Ultrasonographie elastography could be used in carotid arteries atherosclerotic plaques. Various of acoustic characteristics plaques has different elastography and strain contrast.

Prolongation of allograft survival by donor mesenchymal stem cells infusion in rat heart transplantation / 中华器官移植杂志

Objective To investigate the immunomodulatory effect of mesenchymal stem cells (MSCs) and their role in prolonging allograft survival in rat heart transplantation. Methods Inbred Wistar rats were used as donors, and Fisher 344 as recipients. MSC were isolated from femur and tibia bone marrow of donors and cultured in vitro. Mixed lymphocyte reaction assays were performed to assess the immunosuppressive effects of different concentrations of MSC on allogeneic T cell proliferation. Cardiac allograft model was established and according to different intervention measures recipients were divided into two groups (MSC treatment group and control group) (n=8 in each group). In MSC treatment group, recipients were infused with 2×106 MSC via the tail vein at designated intervals (one week before operation, during operation and consecutive three days postoperation), while in control group, the recipients were treated with Ringer's solution at the same interval& At day 5 posttransplantation real-time PCR was used to detect the changes in the expression of Thl and Th2 cytokine genes in transplanted hearts. Results In vitro allogeneic T cell response was greatly suppressed by MSC in a dose-dependent manner. Real-time PCR revealed that IL-1β,IFN-γ, IL-4 and IL-10 were expressed in MSC treatment group, while IL-4 and IL-10 were not expressed in control group but with significantly higher expression of IL-1β and IFN-γ. As compared with control group, survival of MSC-treated allografts was markedly prolonged as compared with control group (mean survivaldays: 12.4±5.3 vs 6.4±2.0, P＜0.05). Conclusion Intravenous adrninistmtion of MSC can prolong the survival of transplanted heart possibly by induction of allograft tolerance through changing Th1/Th2 balance.

Cytotoxicity study of heparin coated polyvinyl chloride material / 生物医学工程学杂志

In this study, heparin ionically coated polyvinyl chloride (PVC) material was prepared by heparin-benzalkonium chloride complex (Group A), heparin-benzalkonium bromide complex (Group B) and heparin-polyethyleneimine compound (Group C). Cytotoxicity evaluation was conducted by direct cell contact evaluation and MTT colorimetry method. The results showed Group A and Group B caused L-929 cells to die out while Group C showed good compatibility with cells. The OD levels of Group A and B were lower than that of the Group C in MTT test. Method A and method B of heparin coating had remarkable cytotoxicity, while method C had little cytotoxicity and could be further studied for clinical use.

Clinical analysis of the children with multiple ventricular septal defects / 中华外科杂志

<p><b>OBJECTIVE</b>To review the experiences in surgical management and diagnosis for the children with multiple ventricular septal defects (VSDs).</p><p><b>METHODS</b>The clinical data of 21 children with multiple VSDs (8 males, 13 females) were analysed retrospectively. Multiple muscle defects in all patients were repaired by left ventricle incision and their near future clinical outcome was investigated.</p><p><b>RESULTS</b>The accuracy of diagnosis was 95.2% and the mortality was 9.5%. No residual shunts were found. Complete atrioventricular block was found early in 2 patients postoperation.</p><p><b>CONCLUSIONS</b>The operative outcome of children with multiple VSDs is satisfied. For these patients detailed preoperative color flow mapping and careful observation during operation are essential to increase the accuracy of diagnosis and prevention of residual shunts.</p>

The mechanical properties of a new Ti-Nb-Zr-Sn alloy with low elastic modulus for dental use / 实用口腔医学杂志

Objective:To study the mechanical properties of a new titanium alloy with lower elastic modulus for prosthodontic use.Methods:Samples of a newly developed Ti-Nb-Zr-Sn alloy with low elastic modulus were prepared.The microstructure,microhardness profile of the specimen cross section were measured by microhardness test meter and metallurgical microscope.Results:The data of the tensile strength(MPa),yield strength(MPa),elongation(%),elastic modulus(GPa) and microhardness(Hv)of Ti-Nb-Zr-Sn alloy were 681.7,410,6,42.1 and 453 respectively.The microstructure was with fine crystal grains.Conclusion: The microstructure and microhardness profile of the Ti-Nb-Zr-Sn alloy may meet the requirement for dental applications.

Comparison of endoscopic and conventional great saphenous vein harvesting in coronary artery bypass grafting / 中国微创外科杂志

Objective To observe the clinical effects of endoscopic great saphenous vein harvesting(ESVH) in coronary artery bypass grafting. Methods Endoscopic great saphenous vein harvesting was performed in 89 patients undergoing coronary artery bypass grafting(CABG) from April 2004 to May 2005.An incision 2 cm in length was made on the knee joint and the great saphenous vein was harvested using the VasoView-5 system.Clinical data of the 89 patients(Endoscopic Group) were compared with another 38 patients undergoing conventional great saphenous vein harvesting for CABG from April 2003 to March 2005(Conventional Group) in respect of complications of the leg, the recovery time to walking,and the patency rate at 6 postoperative months.Results The number of harvested vein grafts in the Endoscopic Group was 2~3(mean,2.6).Complications of the leg were significantly less in the Endoscopic Group(6/89) than in the Conventional Group(8/38)(?~2=4.197,P=0.040).The occurrence of pain and numbness of the leg was 7/89 in the Endoscopic Group and 36/38 in the Conventional Group(?~2=89.740,P=0.000).The occurrence of swelling of the leg was 9/89 in the Endoscopic Group and 30/38 in the Conventional Group(?~2=59.299,P=0.000).The recovery time to walking was significantly shorter in the Endoscopic Group(2.3?0.9 d) than in the Conventional Group(3.4?1.6 d)(t=-4.952,P=0.000).There was no significant difference in the patency rate at 6 postoperative months between the Endoscopic Group(96.0%,48/50) and the Conventional Group(95.3%,19/20)(?~2=0.000,P=1.000).Conclusions Use of endoscopic vein harvesting in coronary artery bypass grafting decreases the incidence of postoperative leg-wound infections,post-operative pain,and length of hospital stay.

A study of cytotoxicity of membrane material of cardiac assist pump / 解放军医学杂志

Objective To study the cytotoxicity of the membrane material of heart assist pump. Methods The membrane materials tested incladed polyurethane (group A) and medical polychloroethylene (group B),and a blank control group with none of the material. L-929 cells (the mouse fibroblasts) were cultured on either material in groups A and B,and 6 cell cultures were without any material. After 24,48 and 72 hours,the growth of cell in groups A,B and the control was observed,and the number was counted. Educts of two materials used in groups A and B was respectively added to culture medium,then the OD was measured every 24h and proliferation rate was determined by MTT test. Results L-929 cells grew very well in groups A and B with less death. The cell counts showed no difference between 2 groups at each time. The OD of group A was always higher than that of group B after 24,48 and 72h ( P

Pulmonany Carcinoma :the Analysis of Therapeutic Effect of Dual Interventional Therapy / 实用放射学杂志

Objective To evaluate the therapeutic effect of pulmonary carcinoma by bronchical arterial infusion (BAI) and bronchical arterial infusion with the addition of pulmonary arterial infusion (PAI).Methods Totally 69 cases with pulmonany cancinoma were treated by intervention therapy .Of them ,38 cases were undergone the bronchical arteriography and arterial infusion and 31 cases were undergone the brochical pulmonany arterial dual infusion.Results The bronchical arteryies taken part in the blood supply of neoplasmin all cases ,while the pulmonany artery only in 77% of cases .The effective ratio of BAI +PAI was 87%, and BAI was 65.7%,there were markly different (?