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Trilayer anisotropic structure versus randomly oriented structure in heart valve leaflet tissue engineering 被引量:1
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作者 Yuriy Snyder Soumen Jana 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第4期423-438,共16页
It has been hypothesized that leaflet substrates with a trilayer structure and anisotropicmechanical properties could be useful for the production of functional and long-lasting tissue-engineered leaflets.To investiga... It has been hypothesized that leaflet substrates with a trilayer structure and anisotropicmechanical properties could be useful for the production of functional and long-lasting tissue-engineered leaflets.To investigate the influence of the anisotropic structural and mechanical characteristics of a substrate on cells,in this study,we electrospun trilayer anisotropic fibrous substrates and randomly oriented isotropic fibrous substrates(used as controls)from polycaprolactone polymers.Consequently,the random substrates had higher radial and lower circumferential tensile properties than the trilayer substrates;however,they had similar flexural properties.Porcine valvular interstitial cells cultured on both substrates produced random and trilayer cell-cultured constructs,respectively.The trilayer cell-cultured constructs had more anisotropic mechanical properties,17%higher cellular proliferation,14%more extracellular matrix(i.e.,collagen and glycosaminoglycan)production,and superior gene and protein expression,suggesting that more cells were in a growth state in the trilayer constructs than in the random constructs.Furthermore,the random and radial layers of the trilayer constructs had more vimentin,collagen,transforming growth factor-beta 1(TGF-ß1),transforming growth factor-beta 3(TGF-ß3)gene expression than in the circumferential layer of the constructs.This study verifies that the differences in structural,tensile,and anisotropic properties of the trilayer and random substrates influence the characteristics of the cells and ECM in the constructs. 展开更多
关键词 heart valve leaflet TRILAYER Tissue engineering Fiber ELECTROSPINNING
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Application of Decellularized Scaffold Combined with Loaded Nanoparticles for Heart Valve Tissue Engineering in vitro 被引量:4
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作者 邓诚 董念国 +5 位作者 史嘉玮 陈思 徐磊 史峰 胡行健 张先正 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2011年第1期88-93,共6页
The purpose of this study was to fabricate decelluarized valve scaffold modified with polyethylene glycol nanoparticles loaded with transforming growth factor-β1(TGF-β1),by which to improve the extracellular matri... The purpose of this study was to fabricate decelluarized valve scaffold modified with polyethylene glycol nanoparticles loaded with transforming growth factor-β1(TGF-β1),by which to improve the extracellular matrix microenvironment for heart valve tissue engineering in vitro.Polyethylene glycol nanoparticles were obtained by an emulsion-crosslinking method,and their morphology was observed under a scanning electron microscope.Decelluarized valve scaffolds,prepared by using trypsinase and TritonX-100,were modified with nanoparticles by carbodiimide,and then TGF-β1 was loaded into them by adsorption.The TGF-β1 delivery of the fabricated scaffold was measured by asing enzyme-linked immunosorbent assay.Whether unseeded or reseeded with myofibroblast from rats,the morphologic,biochemical and biomechanical characteristics of hybrid scaffolds were tested and compared with decelluarized scaffolds under the same conditions.The enzyme-linked immunosorbent assay revealed a typical delivery of nanoparticles.The morphologic observations and biological data analysis indicated that fabricated scaffolds possessed advantageous biocompatibility and biomechanical property beyond decelluarized scaffolds.Altogether this study proved that it was feasible to fabricate the hybrid scaffold and effective to improve extracellular matrix microenvironment,which is beneficial for an application in heart valve tissue engineering. 展开更多
关键词 heart valve tissue engineering polyethylene glycol nanoparticle transforming growth factor-β1 decellularized scaffold
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Effect of L-carnitine on Cardiomyocyte Apoptosis and Cardiac Function in Patients Undergoing Heart Valve Replacement Operation 被引量:1
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作者 向道康 孙宗全 +3 位作者 夏家红 董念国 杜心灵 陈新忠 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2005年第5期501-504,共4页
Summary: The effects of L-carnitine, as an ingredient of cardioplegia solution, on cardiac function and cardiomyocyte apoptosis in patients undergoing heart valve replacement operation were investigated. Twenty-three... Summary: The effects of L-carnitine, as an ingredient of cardioplegia solution, on cardiac function and cardiomyocyte apoptosis in patients undergoing heart valve replacement operation were investigated. Twenty-three cases undergoing heart valve replacement with cardiopulmonary bypass (CPB) were randomly allocated into two groups: L-carnitine group (n=12, 12 g/L L-carnitine was put in the ST. Thomas cardioplegia) and control group (n=11, identical to the L-carnitine group except that normal saline was administered instead of L-carnitine). Serum cardial troponin I (cTnI) levels, the left ventricular ejection fraction (LVEF), and cardiac index (CI) were measured perioperatively. A bit of myocardial tissue obtained from right atria was taken before CPB and by the end of intracardiac procedure to undergo electron microscopy examination and estimate apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). From the end of CPB to 3 days after operation, the serum levels of cTnI in the L-carnitine group was significantly lower than that in the control group (P〈0.05). Heart color ultrasonogram showed that the CI index and LVEF at 7th day postoperatively in the L-carnitine group were significantly higher than in the control group (P〈0.05). Compared to the control group, L-carnitine significantly alleviated the morphologic changes of cardiac muscle cells (electron microscopy examination) and decreased the amounts of apoptotic cardiac muscle cells (TUNEL). Furthermore, the dosage of vasoactive drugs used after operation was significantly less in the L-carnitine group (P〈0.01). It was concluded that L-carnitine cardioplegia solution could improve cardiac function in patients undergoing heart valve replacement operation and alleviate CPB-mediated apoptosis of cardiac muscle cells. 展开更多
关键词 heart valve replacement operation cardioplegia solution cardiac function APOPTOSIS L-CARNITINE
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Univariate Risk Factors for Prolonged Mechanical Ventilation in Patients Undergoing Prosthetic Heart Valves Replacement Surgery 被引量:1
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作者 Ommari Baaliy Mkangara 张凯伦 +2 位作者 杨运海 Saumu Tobbi Mweri Theresia.M.Kobelo 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第6期693-695,共3页
Data from 736 patients undergoing prosthetic heart valve replacement surgery and concomitant surgery (combined surgery) from January 1998 to January 2004 at Union Hospital were retrospectively reviewed. Univariate l... Data from 736 patients undergoing prosthetic heart valve replacement surgery and concomitant surgery (combined surgery) from January 1998 to January 2004 at Union Hospital were retrospectively reviewed. Univariate logistic regression analyses were conducted to identity risk factors for prolonged mechanical ventilation. The results showed that prolonged cardiopulmonary bypass duration, prolonged aortic cross clamp time and low ejection fraction less than 50 percent (50 %) were found to be independent predictors for prolonged mechanical ventilation. Meanwhile age, weight, and preoperative hospital stay (days) were not found to be associated with prolonged mechanical ventilation. It was concluded that. for age and weight, this might be due to the lower number of old age patients (70 years and above) included in our study and genetic body structure of majority Chinese population that favor them to be in normal weight, respectively. 展开更多
关键词 prolonged mechanical ventilation prosthetic heart valves replacement SURGERY
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Development of Biofunctionalized Cellulose Acetate Nanoscaffolds for Heart Valve Tissue Engineering 被引量:1
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作者 Eirini Chainoglou Varvara Karagkiozaki +3 位作者 Theodora Choli-Papadopoulou Charisios Mavromanolis Argiris Laskarakis Stergios Logothetidis 《World Journal of Nano Science and Engineering》 2016年第4期129-152,共25页
Currently-used mechanical and biological heart valve prostheses have a satisfactory short-term performance, but may exhibit several major drawbacks on the long-term. Mechanical prostheses, based on carbon, metallic an... Currently-used mechanical and biological heart valve prostheses have a satisfactory short-term performance, but may exhibit several major drawbacks on the long-term. Mechanical prostheses, based on carbon, metallic and polymeric components, require permanent anticoagulation treatment, and their usage often leads to adverse reactions, e.g. thromboembolic complications and endocarditis. In recent years, there is a need for a heart valve prosthesis that can grow, repair and remodel. The concept of tissue engineering offers good prospects into the development of such a device. An ideal scaffold should mimic the structural and purposeful profile of materials found in the natural extracellular matrix (ECM) architecture. The goal of this study was to develop cellulose acetate scaffolds (CA) for valve tissue regeneration. After their thorough physicochemical and biological characterization, a biofunctionalization process was made to increase the cell proliferation. Especially, the surface of scaffolds was amplified with functional molecules, such as RGD peptides (Arg-Gly-Asp) and YIGSRG laminins (Tyrosine-Isoleucine-Glycine-Serine-Arginine-Glycine) which immobilized through biotin-streptavidin bond, the strongest non-covalent bond in nature. Last step was to successfully coat an aortic metallic valve with CA biofunctionallized nanoscaffolds and cultivate cells in order to create an anatomical structure comparable to the native valve. Promising results have been obtained with CA-based nanoscaffolds. We found that cells grown successfully on the biofunctionalized valve surface thereby scaffolds that resemble the native tissues, elaborated with bioactive factors such as RGD peptides and laminins not only make the valve’s surface biocompatible but also they could promote endothyliazation of cardiac valves causing an anti-coagulant effect 展开更多
关键词 heart valve Tissue Engineering Cellulose Acetate Scaffolds NANOMATERIALS POLYMERS Atomic Force Microscopy
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In vitro calcification studies on bioprosthetic and decellularized heart valves under quasi-physiological flow conditions
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作者 Cristian C.D’Alessandro Andreas Dimopoulos +4 位作者 Sofia Andriopoulou Gerasimos A.T.Messaris Sotirios Korossis Petros Koutsoukos Dimosthenis Mavrilas 《Bio-Design and Manufacturing》 SCIE EI CSCD 2021年第1期10-21,共12页
The lifespan of biological heart valve prostheses available in the market is limited due to structural alterations caused by calcium phosphate deposits formed from blood plasma in contact with the tissues.The objectiv... The lifespan of biological heart valve prostheses available in the market is limited due to structural alterations caused by calcium phosphate deposits formed from blood plasma in contact with the tissues.The objective of this work is to present a comparative methodology for the investigation of the formation of calcium phosphate deposits on bioprosthetic and tissue-engineered scaffolds in vitro and the influence of mechanical forces on tissue mineralization.Based on earlier investigations on biological mineralization at constant supersaturation,a circulatory loop simulating dynamic blood flow and physiological pressure conditions was developed.The system was appropriately adapted to evaluate the calcification potential of decellularized(DCV)and glutaraldehyde-fixed(GAV)porcine aortic valves.Results indicated that DCV calcified at higher,statistically nonsignificant,rates in comparison with GAV.This difference was attributed to the tissue surface modifications and cell debris leftovers from the decellularization process.Morphological analysis of the solids deposited after 20 h by scanning electron microscopy in combination with chemical microanalysis electron-dispersive spectroscopy identified the solid formed as octacalcium phosphate(Ca8(PO4)6H2·5H2O,OCP).OCP crystallites were preferentially deposited in high mechanical stress areas of the test tissues.Moreover,GAV tissues developed a significant transvalvular pressure gradient increase past 36 h with a calcium deposition distribution similar to the one found in explanted prostheses.In conclusion,the presented in vitro circulatory model serves as a valuable prescreening methodology for the investigation of the calcification process of bioprosthetic and tissue-engineered valves under physiological mechanical load. 展开更多
关键词 Reactors CALCIFICATION Constant composition reactor heart valve In vitro Mechanical load Tissue engineering
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Fabrication of a Novel Hybrid Scaffold for Tissue Engineered Heart Valve
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作者 洪昊 董念国 +4 位作者 史嘉玮 陈思 郭超 胡平 齐宏旭 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第5期599-603,共5页
The aim of this study was to fabricate biomatrix/polymer hybrid scaffolds using an electrospinning technique. Then tissue engineered heart valves were engineered by seeding mesenchymal stromal cells (MSCs) onto the ... The aim of this study was to fabricate biomatrix/polymer hybrid scaffolds using an electrospinning technique. Then tissue engineered heart valves were engineered by seeding mesenchymal stromal cells (MSCs) onto the scaffolds. The effects of the hybrid scaffolds on the proliferation of seed cells, formation of extracellular matrix and mechanical properties of tissue engineered heart valves were investigated. MSCs were obtained from rats. Porcine aortic heart valves were decellularized, coated with poly(3-hydroxybutyrate-co-4-hydroxybutyrate) using an electrospinning technique, and reseeded and cultured over a time period of 14 days. In control group, the decellularized valve scaffolds were reseeded and cultured over an equivalent time period. Specimens of each group were examined histologically (hematoxylin-eosin [HE] staining, immunohistostaining, and scanning electron microscopy), biochemically (DNA and 4-hydroxyproline) and mechanically. The results showed that recellularization was comparable to the specimens of hybrid scaffolds and controls. The specimens of hybrid scaffolds and controls revealed comparable amounts of cell mass and 4-hydroxyproline (P〉0.05). However, the specimens of hybrid scaffolds showed a significant increase in mechanical strength, compared to the controls (P〈0.05). This study demonstrated the superiority of the hybrid scaffolds to increase the mechanical strength of tissue engineered heart valves. And compared to the decellularized valve scaffolds, the hybrid scaffolds showed similar effects on the proliferation of MSCs and formation of extracellular matrix. It was believed that the hybrid scaffolds could be used for the construction of tissue engineered heart valves. 展开更多
关键词 tissue engineered heart valve hybrid scaffold ELECTROSPINNING mesenchymal stem cells
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Imaging of pannus formation in patients with mechanical heart valves
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作者 Sabahattin Gündüz Mehmet Ozkan Mahmut Yesin 《World Journal of Cardiology》 CAS 2015年第11期822-823,共2页
Patient-prosthesis mismatch(PPM) should be recognized in patients with elevated transprosthetic gradients but without leaflet immobility, since the treatment strategy may differ in either etiology. However, thrombus a... Patient-prosthesis mismatch(PPM) should be recognized in patients with elevated transprosthetic gradients but without leaflet immobility, since the treatment strategy may differ in either etiology. However, thrombus and/or pannus formation should be excluded before a diagnosis of PPM is made. Particularly, pannus formation may not be diagnosed with 2-dimensional transesophageal echocardiography. Electrocardiographically gated 64-section multidetector computed tomography(MDCT) may be a promising tool in diagnosing or excluding pannus formation. Our report underlines the utility of MDCT in this regard and also emphasizes the importance of recognition of PPM as a differential diagnosis in such patients. 展开更多
关键词 Multidetector computed tomography Pannus formation Patient prosthesis mismatch Prosthetic heart valves Transesophageal echocardiography
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Body-temperature circadian rhythm in 67 patients after heart valve replacement surgery secondary to valvular heart disease
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作者 Xiao-Ying Jiang Cong Wang 《International Journal of Nursing Sciences》 2014年第1期64-68,共5页
Purpose:Patient body temperature was monitored after cardiac valve replacement,in order to explore the characteristics of body-temperature circadian rhythm and the factors influencing that rhythm.Methods:A cohort of 6... Purpose:Patient body temperature was monitored after cardiac valve replacement,in order to explore the characteristics of body-temperature circadian rhythm and the factors influencing that rhythm.Methods:A cohort of 67 patients who received cardiac valve replacement in a Fuzhou,Fujian province,China,general hospital underwent temperature measurements and analysis(by cosine curve)of their body-temperature circadian rhythm.A biological rhythm model was established through principal component analysis and evaluation of biological rhythm features.Multiple circadian parameters were included through linear regression analysis.Results:Patients’temperature after cardiac valve replacement exhibited circadian characteristics(p<0.05),among which the scores of temperature mesor,amplitude,and acrophase were respectively(37.610.08),(0.100.09),and33(e355,e119).Body-temperature rhythms were influenced by both gender and cardiopulmonary bypass time(p<0.05).Conclusion:Although some patients’circadian characteristics disappeared after cardiac valve replacement,circadian rhythms remained intact for most patients.Measures that were found to mitigate body-temperature circadian rhythm disruption included building a natural rhythm of light/darkness and decreasing cardiopulmonary bypass time. 展开更多
关键词 Body temperature Circadian rhythm heart valve replacement Rheumatic heart disease
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Pathogenic Mineralization of Calcium Phosphate on Human Heart Valves
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作者 王慧 冯庆玲 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期150-152,共3页
When calcium phosphate forms in soft tissues such as blood vessels and heart valves, it causes disease. The abnormal formation of calcium phosphate is called pathogenic mineralization or pathogenic calcification. Cas... When calcium phosphate forms in soft tissues such as blood vessels and heart valves, it causes disease. The abnormal formation of calcium phosphate is called pathogenic mineralization or pathogenic calcification. Cases of rheumatic heart disease (RHD) always occur with fibrotic and calcified tissue of heart valve. In this article, samples taken from calcified human heart wdves were studied. The characterization was performend by scanning electronic microscope, X-ray Diffraction and transmission electron microscopy with selective diffraction patterns. It is found for the first time that calcium phosphate grains existing in the calcified human heart valves contain octacalcium phosphate ( OCP ). 展开更多
关键词 CALCIFICATION heart valve octacalcium phosphate (OCP)
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VALVE REPLACEMENT WITH BILEAFLET HEART VALVE PROSTHESIS: FOLLOW-UP OF 170 CASES
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作者 许锁春 黄庆恒 +2 位作者 李光志 耿希刚 孙立 《Journal of Pharmaceutical Analysis》 CAS 1997年第1期66-69,73,共5页
From Feb. 1989 to May 1996, 170 patients underwent valve replacement with bileaflet heart valve prosthesis. There were 13 early deaths (mortality of 7-65% ), and 6 late deaths. The Preoperative cardiac function (NYHA)... From Feb. 1989 to May 1996, 170 patients underwent valve replacement with bileaflet heart valve prosthesis. There were 13 early deaths (mortality of 7-65% ), and 6 late deaths. The Preoperative cardiac function (NYHA) was grade Ⅱ in 96 cases, Ⅳ in 35 cases and Ⅲ to Ⅳ in 77. 1%.Follow-up of the survivors from 3 to 87 (average 39) months showed that most of them could do light and moderate physical labor, and cardiac function was restored to grade Ⅰ~ Ⅱ in 96. 4%. Anti-coagulating bleeding is a common complicaion. However, severe embolism and valve dysfunction had not been found- The authors analysed the causes of death and follow-up data, then emphasized that it was necessary that valve replacement be performed as early as possible, and bileaflet heart valve substitute was the best choice. Furthermore, therapy of little dose anti-coagulating drug(warfarin 1.5~3- 0mg/d) is safe and dependable to most of the patients. 展开更多
关键词 Bileaflet heart valve prosthesis valve replacement HEMODYNAMICS
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Effect of Psychological Nursing on the Mental State and Quality of Life of Patients After Heart Valve Replacement for Rheumatic Heart Disease
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作者 Lijuan Wu Liping Feng Hui Chen 《Journal of Clinical and Nursing Research》 2021年第5期142-146,共5页
Objective:To explore the effect of psychological nursing on the mental state and quality of life of patients after heart valve replacement for rheumatic heart disease.Methods:Seventy-four patients with rheumatic heart... Objective:To explore the effect of psychological nursing on the mental state and quality of life of patients after heart valve replacement for rheumatic heart disease.Methods:Seventy-four patients with rheumatic heart disease that underwent heart valve replacement in Zhenjiang First People's Hospital from January 2017 to May 2020 were selected as the research subjects.Thirty-seven patients that were treated from January 2017 to September 2018 were included in the control group.Routine care was provided for the patients in the control group.From October 2018 to May 2020,the Department of Cardiothoracic Surgery improved their preoperative and postoperative psychological care.Thirty-seven patients that were treated during this period were included in the research group.The research group received psychological nursing care in addition to routine care.The efiects of different nursing modes on the quality of life and postoperative mental state of the patients were determined.Results:The scores for depression,anxiety,somatization,and compulsion in the research group were significantly lower than those in the control group(p<0.05);the scores for the quality of life of patients in the research group were significantly higher than those in the control group(p<0.05).Conclusions:Strengthening psychological nursing for patients with rheumatic heart disease is helpful to improve their quality of life and mental state after heart valve replacement. 展开更多
关键词 Psychological nursing Rheumatic heart disease heart valve replacement Quality of life
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Isolated mitral valve replacement with Guangdong-Ⅰ porcine bioprostheses in rheumatic heart valve disease: analysis of 166 cases with long-term follow-up
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作者 张镜芳 《外科研究与新技术》 2003年第2期110-110,共1页
Objective To study the long-term effects of mitral valve replacement with bioprostheses in rheumatic heart valve disease. Methods 166 patients with rheumatic heart valve disease underwent isolated mitral valve replace... Objective To study the long-term effects of mitral valve replacement with bioprostheses in rheumatic heart valve disease. Methods 166 patients with rheumatic heart valve disease underwent isolated mitral valve replacement from Jan. 1978 to Dec. 1985. 79 Patients were male and 87 female. Patients’ age ranged from 11 to 53 years [mean (29.4 ± 9.9) years]. The patients were classified into two groups: group 1 (age【 30 years) included 84 patients, group 2 (age≥30 years) 82 cases. Mean CTR is 0.68 *0.08. Most patients were in NYHA function class Ⅲ-Ⅳ. 76. 3% of patients had atrial fibrillation. 6 patients had pre-operative cerebral vascular accidents. Postoperative deaths were excluded. Follow-up extended from 0.4 year to 19.4 years. Results Actuarial estimate of survival rate at 14 years is (52.5 ± 7.0)%. Heart function was improved to class Ⅰ - Ⅱ in most of patients. Late structural valve deterioration occurred in 89 patients. Among them, 59 were re-operated. Actuarial estimate of freedom from 展开更多
关键词 with porcine bioprostheses in rheumatic heart valve disease analysis of 166 cases with long-term follow-up Isolated mitral valve replacement with Guangdong
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Low-intensity anticoagulation therapy in the pregnant women with mechanical heart valves:a report with 56 cases
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作者 董力 《外科研究与新技术》 2011年第3期174-175,共2页
Objective To evaluate the method of low-intensity anticoagulation therapy in the pregnant women who had received mechanical heart valve replacemant,and the effects of warfarin on the pregnant women and their fetus. Me... Objective To evaluate the method of low-intensity anticoagulation therapy in the pregnant women who had received mechanical heart valve replacemant,and the effects of warfarin on the pregnant women and their fetus. Methods This retrospective study involved 56 pregnant women (61 pregnancies) who had received mechanical heart valve replacement. Their pregnant status,delivery, and anticoagulation therapy were observed 展开更多
关键词 Low-intensity anticoagulation therapy in the pregnant women with mechanical heart valves
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Recent progress in functional modification and crosslinking of bioprosthetic heart valves
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作者 Cheng Zheng Li Yang Yunbing Wang 《Regenerative Biomaterials》 SCIE EI CSCD 2024年第1期1-16,共16页
Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high mortality.Heart valve replacement surgery has been r... Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high mortality.Heart valve replacement surgery has been recognized as golden standard for the treatment of VHD.Owing to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of VHD.However,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune response.To prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of SVD.In this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs. 展开更多
关键词 bioprosthetic heart valves MODIFICATION CROSSLINKING anticalcification ANTITHROMBOSIS
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Bioinspired polymeric heart valves derived from polyurethane and natural cellulose fibers 被引量:1
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作者 Feng Guo Rizheng Han +3 位作者 Jishan Ying Zeping Zhang Rui Yang Xing Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第13期178-187,共10页
In this work,bioinspired anisotropic polymeric heart valves were fabricated using composite materials from polyurethane(PU)and natural cellulose fiber bundles.Cellulose fibers with good alignment were obtained from ba... In this work,bioinspired anisotropic polymeric heart valves were fabricated using composite materials from polyurethane(PU)and natural cellulose fiber bundles.Cellulose fibers with good alignment were obtained from balsa wood by a top-down process,which were then distributed in polyurethane to pre-pare cellulose fiber bundles reinforced polyurethane(CPU)by hot pressing.The storage modulus of the CPU along the direction parallel to the fiber alignment was 16.70±0.80 MPa,whereas that along the direction perpendicular to the fiber alignment was 8.41±0.94 MPa by dynamic mechanical analysis(DMA)tests at 1 Hz,comparable to aortic valve leaflets.Moreover,2-methacryloyloxyethyl phosphoryl-choline(MPC)was grafted onto the CPU surface(CPU-MPC)to improve hemocompatibility.With MPC modification,the water contact angle decreased significantly from 54.58°±2.98°to 26.42°±3.50°,and the platelet adhesion was reduced by 92%,compared to the original CPU.In vitro cell culture proved that both CPU and CPU-MPC samples did not show any cytotoxicity.Furthermore,the CPU composites were used to fabricate polymeric heart valves,which showed excellent hydrodynamic performance with a large orifice area(1.70 cm 2)and low regurgitation fraction(0.7%),meeting the requirements of ISO 5840-2 standard. 展开更多
关键词 Polymeric heart valve ANISOTROPY Cellulose fibers POLYURETHANE
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Construction of tissue-engineered heart valves by using decellularized scaffolds and endothelial progenitor cells 被引量:13
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作者 FANG Ning-tao XIE Shang-zhe WANG Song-mei GAO Hong-yang WU Chun-gen PAN Luan-feng 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第8期696-702,共7页
Background Tissue-engineered heart valves have the potential to overcome the limitations of present heart valve replacements. This study was designed to develop a tissue engineering heart valve by using human umbilica... Background Tissue-engineered heart valves have the potential to overcome the limitations of present heart valve replacements. This study was designed to develop a tissue engineering heart valve by using human umbilical cord blood-derived endothelial progenitor cells (EPCs) and decellularized valve scaffolds. Methods Decellularized valve scaffolds were prepared from fresh porcine heart valves. EPCs were isolated from fresh human umbilical cord blood by density gradient centrifugation, cultured for 3 weeks in EGM-2-MV medium, by which time the resultant cell population became endothelial in nature, as assessed by immunofluorescent staining. EPC-derived endothelial cells were seeded onto the decellularized scaffold at 3 × 10^6 cells/cm^2 and cultured under static conditions for 7 days. Proliferation of the seeded cells on the scaffolds was detected using the MTT assay. Tissue-engineered heart valves were analyzed by HE staining, immunofluorescent staining and scanning electron microscopy. The anti-thrombogenic function of the endothelium on the engineered heart valves was evaluated by platelet adhesion experiments and reverse transcription-polymerase chain reaction (RT-PCR) analysis for the expression of endothelial nitric oxide synthase (eNOS) and tissue-type plasminogen activator (t-PA).Results EPC-derived endothelial cells showed a histolytic cobblestone morphology, expressed specific markers of the endothelial cell lineage including von Willebrand factor (vWF) and CD31, bound a human endothelial cell-specific lectin, Ulex Europaeus agglutinin-1 (UEA-1), and took up Dil-labeled low density lipoprotein (Dil-Ac-LDL). After seeding on the decellularized scaffold, the cells showed excellent metabolic activity and proliferation. The cells formed confluent endothelial monolayers atop the decellularized matrix, as assessed by HE staining and immunostaining for vWF and CD31. Scanning electron microscopy demonstrated the occurrence of tight junctions between cells forming the confluent monolayer. Platelets adhesion experiments suggested that the neo-endothelium was non-thrombogenic. The expression levels of eNOS and t-PA genes in the neo-endothelium were quite similar to those in human umbilical vein endothelial cells. Conclusions EPCs isolated from the human umbilical cord blood can differentiate into endothelial cells in vitro and form a functional endothelium atop decellularized heart valve scaffolds. Thus, EPCs may be a promising cell source for constructing tissue-engineered heart valves. 展开更多
关键词 endothelial progenitor cell tissue-engineered heart valve decellularized matrix platelet adhesion
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Clinical risk score for postoperative pneumonia following heart valve surgery 被引量:1
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作者 Da-Shuai Wang Xiao-Fan Huang +2 位作者 Hong-Fei Wang Sheng Le Xin-Ling Du 《Chinese Medical Journal》 SCIE CAS CSCD 2021年第20期2447-2456,共10页
Background:Postoperative pneumonia(POP)is one of the most common infections following heart valve surgery(HVS)and is associated with a significant increase in morbidity,mortality,and health care costs.This study aimed... Background:Postoperative pneumonia(POP)is one of the most common infections following heart valve surgery(HVS)and is associated with a significant increase in morbidity,mortality,and health care costs.This study aimed to identify the major risk factors associated with the occurrence of POP following HVS and to derive and validate a clinical risk score.Methods:Adults undergoing open HVS between January 2016 and December 2019 at a single institution were enrolled in this study.Patients were randomly assigned to the derivation and validation sets at 1:1 ratio.A prediction model was developed with multivariable logistic regression analysis in the derivation set.Points were assigned to independent risk factors based on their regression coefficients.Results:POP occurred in 316 of the 3853 patients(8.2%).Multivariable analysis identified ten significant predictors for POP in the derivation set,including older age,smoking history,chronic obstructive pulmonary disease,diabetes mellitus,renal insufficiency,poor cardiac function,heart surgery history,longer cardiopulmonary bypass,blood transfusion,and concomitant coronary and/or aortic surgery.A 22-point risk score based on the multivariable model was then generated,demonstrating good discrimination(C-statistic:0.81),and calibration(Hosmer-Lemeshowχ^(2)=8.234,P=0.312).The prediction rule also showed adequate discriminative power(C-statistic:0.83)and calibration(Hosmer-Lemeshowχ^(2)=5.606,P=0.691)in the validation set.Three risk intervals were defined as low-,medium-,and high-risk groups.Conclusion:We derived and validated a 22-point risk score for POP following HVS,which may be useful in preventive interventions and risk management.Trial Registration:Chictr.org,ChiCTR1900028127;http://www.chictr.org.cn/showproj.aspx?proj=46932. 展开更多
关键词 Postoperative pneumonia heart valve surgery Risk factor Prediction model Risk score
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Low standard oral anticoagulation therapy for Chinese patients with St.Jude mechanical heart valves 被引量:4
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作者 孙晓刚 胡盛寿 +1 位作者 祁国奇 周玉燕 《Chinese Medical Journal》 SCIE CAS CSCD 2003年第8期1175-1178,共4页
Objective To study the efficacy of the low standard oral anticoagulation therapy following St Jude Medical (SJM) valve implantation for Chinese patients.Methods Totally 805 patients with a mean age of 42.70±11... Objective To study the efficacy of the low standard oral anticoagulation therapy following St Jude Medical (SJM) valve implantation for Chinese patients.Methods Totally 805 patients with a mean age of 42.70±11.09 years,enrolled into this study. Among them,230 underwent aortic valve replacements (AVR),381 mitral valve replacements (MVR),189 double valve replacements (DVR) and 5 tricuspid valve replacememts (TVR). All patients received postoperative oral anticoagulation therapy based on a low standard of international normalized ratio (INR,2.0-2.5). Of the 805 patients,710 were followed up for 0.25-13 years (a median,4.15 years). Results Postoperatively,17 adverse events occurred. Operative mortality was 2.11%. The most frequent cause of operative mortality was a low cardiac output. During follow-up,there were 47 anticoagulant-induced hemorrhages [1.59%/patient-year (pt-yr)],10 cases of thromboembolism (0.34%/pt-yr),and 3 mechanical valve thromboses (0.19%/pt-yr). There were 44 late deaths and the linearized late mortality rates were 0.51%pt-yr. Estimates of actuarial survival for all patients at 5 and 10 years was 97.45% (0.70%) and 77.96% (17.44%),respectively.Conclusions A low target INR range of 2.0-2.5 is preferable for Chinese patients so as to reduce the severe bleeding complications in those with conventionally higher levels of INR. The long-term results were satisfactory in terms of the numbers of those who suffered thrombosis,embolism and bleeding. 展开更多
关键词 heart valve prosthesis·anticoagulants·international normalized ratio·hemorrhage·thromboembolism
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Is the European System for Cardiac Operative Risk Evaluation useful in Chinese patients undergoing heart valve surgery? 被引量:4
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作者 ZHENG Shuai ZHENG Zhe +1 位作者 FAN Hong-guang HU Sheng-shou 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第20期3624-3628,共5页
Background The European System for Cardiac Operative Risk Evaluation (EuroSCORE) is one of the most widely used risk models for the predicting mortality after cardiac surgery. The aim of this study was to validate t... Background The European System for Cardiac Operative Risk Evaluation (EuroSCORE) is one of the most widely used risk models for the predicting mortality after cardiac surgery. The aim of this study was to validate the EuroSCORE model for predicting operative mortality in heart valve surgery on a Chinese multicenter database and comparing the performance of EuroSCORE with our new risk stratification system, the Sino System for Coronary Operative Risk Evaluation (SinoSCORE). Methods Data from patients undergoing heart valve surgery between January 2007 and December 2008 were retrospectively collected, from 43 hospitals in China. The EuroSCORE and the SinoSCORE were calculated for each patient. Mortality was defined as any in-hospital death. Area under the receiver operating characteristics curve (AUC) was used to study the discriminatory abilities of the models. The Hosmer-Lemeshow (H-L) goodness-of-fit test was used to study the calibration of the predictive models. Results A total of 15 367 patients were analyzed. For the entire cohort, the observed mortality was 2.34%, the predicted mortality was 3.71% (additive), 3.19% (logistic) and 3.66% (SinoSCORE). AUC was 0.747 for SinoSCORE, 0.699 additive and 0.696 for logistic EuroSCORE. Calibration of SinoSCORE and additive EuroSCORE was good (H-L: P=-0.250 and P=0.051, respectively), but the logistic EuroSCORE model had a poor calibration (H-L: P〈0.05). The discriminatory ability and calibration of the SinoSCORE were good in low- and high-risk patients, However, the discriminatory ability of the EuroSCORE model was poor in all risk deciles. Conclusions The EuroSCORE does not accurately predict mortality in Chinese patients with heart valve surgery, and the SinoSCORE is superior to the EuroSCORE at predicting in-hospital mortality in Chinese heart valve surgery patients. 展开更多
关键词 risk evaluation European System for Cardiac Operative Risk Evaluation heart valve surgery
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