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        find Keyword "Heart" 199 results
        • APPLICATION OF SLEEVE ANASTOMOSIS IN DEVELOPMENT OF CERVICAL HEART TRANSPLANTATION IN RATS

          Objective To simplify surgical technique andincrease postoperative survival rate, sleeve anastomosis technique combined cuff technique was used in developing the model of cervical heart transplantation in rats. Methods In this model, the hearts from 25 male SD rats were transplanted into the neck of Wistar rats by anastomosing the donor innominate artery to the recipient right common carotid artery by use of sleeve technique, and the donor pulmonary artery to the recipient right external jugular vein by use of cuff technique. After operation,the rats were treated with cyclosporine A (1.5mg/kg, q.d.), transplanted hearts were followed by daily inspection or palpation and the allograft survival time was more than 3 days as the standard of successful operation. Results The mean operative time was (48.7±3.4) min, with a successful rate of 88%(22/25). Complications were anastomotic hemorrhage( 1 case) and thrombosis(2 cases). During the followup period, 6 rats died of pulmonary infection, abscess in the neck,liver or bladder tumor. The remaining 16 transplanted hearts survived more than3 months. Conclusion The modified operation have advantages ofless operative procedure, shorter operation and ischemia time and easier monitoring of graft function. 

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        • Cryopreserved Homograft Pericardium Patch in Staged Repair of Tetralogy of Fallot

          Objective To compare the difference of effect while using homograft pericardium patch and Gore- tex patch in staged repair of tetralogy of Fallot(TOF) to enlarge the right ventricular outflow tract (RVOT). Methods Twenty-eight patients with TOF who underwent the staged complete repair were divided into 2 groups according to the date of surgery. Gore-rex group, 13 cases, their RVOT were enlarged with Gore-tex patches. Cryopreserved homograft pericardium patch group, 15 cases, their RVOT were enlarged with cryopreserved homograft pericardium patches. Clinical results and follow-up results were compared. Results There were 1 operative death in Gore-tex patch group (7. 7%), and 1 early postoperative death in cryopreserved homograft pericardium patch group (6. 7%). Hemostasia time, the pericardial cavity drainage volume in cryopreserved homograft pericardium patch group were less than those in Gore-tex patch group (P〈0. 01). All patients were followed-up for 0.8-4.5years. The residual obstruction rate at RVOT level in Gore-tex patch group was higher than that in cryopreserved homograft pericardium patch group by echocardiography (P〈0.01). No calcification shadow was found on the chest X-ray. Conclusion Homograft pericardium is the tissue with high density and intensity, its elasticity and compliance are good. Using homograft pericardium patch may be helpful to decrease the residual obstruction of RVOT after operation. It can be adapted as a repairing material in heart surgery.

          Release date:2016-08-30 06:26 Export PDF Favorites Scan
        • Progress of the Third Generation Blood Pumps

          Abstract: The ventricle assist device has emerged as an important therapeutic option in the treatment of both acute and chronic heart failure. The blood pumps which are the major components of ventricle assist devices have also progressed to the third generation. The magnetic and/or liquid levitation technologies have been applied into the third generation blood pumps. The impellers which drive blood are levitated in the blood pumps. The third generation blood pumps are mainly composed of the levitation system and the driving system. The development of the third generation blood pumps has three stages: the stage of foreign motor indirectly driving the impeller with the levitation and driving system separated, the stage of motor directly driving the impeller with the levitation and driving system separated, and the stage of levitation system integrated with the driving system. As the impellers do not contact with other structures, the third generation blood pumps possess the advantages of low thrombosis, less hemolysis and high energy efficiency ratio. Currently most of the third generation blood pumps are in the research stage, but a few number of them are used in clinical trials or applying stage. In this article, the history, classification, mechanism and research situation of the third generation blood pumps are reviewed.

          Release date:2016-08-30 06:02 Export PDF Favorites Scan
        • A Randomized Controlled Trial of Concomitant Tricuspid Annuloplasty for Patients Underwent Mitral Valve Replacement: UCG Evaluation 2 Years After Surgery

          Objective To evaluate the right ventricular function of the patients 2 years after surgery by ultrasonic cardiography (UCG) who underwent mitral valve replacement (MVR) concomitant tricuspid annuloplasty (TAP). Method We finally identified 36 patients required MVR with tricuspid valve annular dilation concomitant merely mild tricuspid regurgitaion (TR) based on preoperative UCG in our hospital between April and November 2012 year. All patients were randomly divided into two groups by digital table including a tricuspid annuloplasty group (a TAP group, n=18, 7 males and 11 females at age of 45.67±12.49 years) and a no-tricuspid annuloplasty group (a NTAP group, n=18, 6 males and 12 females at age of 45.44±10.48 years). General clinical data and extracorporeal circulation data were recorded. UCG evaluation was practiced preoperation, alone with 1 week, 6 months, and 2 years after surgery. Results Two years postoperative maximal long-axis of RA (RAmla), mid-RA minor distance (RAmmd), right ventricle dimension-1(RVD1) , right ventricular fractional area change (RVFAC), 3D RV end-systolic volume (3DRVESV), tricuspid valve annular end-diastolic dimension (TVAEDD), tricuspid valve annular end-systolic dimension (TVAESD) of patients were all smaller in the TAP group than those in the NTAP group. Yet right ventricular ejection fraction (RVEF), percent shorting of tricuspid valve annulus (PSTVA) were greater in the TAP group than those in the NTAP group, although there was no statistical difference between the two groups in two years postoperative 3D RV end-diastolic volume (3DRVEDV). The patients in the TAP group had a superior trend than that of the NTAP group. Moreover, the patients' TR constituent ratio in the TAP group was much better than that of the NTAP group in 2 year after operation. Conclusions Concomitant tricuspid annuloplasty for patients with tricuspid valve annulus dilation and mild TR underwent MVR is favorable for the recovery of their 2 years postoperative function of tricuspid valve and right ventricle. It is benefit to reduce patient's long term postoperative TR residues and exacerbation.

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        • Combination Transplantation of Bone Marrow Mesenchymal Stem Cells and Hepatocyte Growth Factor Gene in the Treatment of Chronic Ischemic Heart Disease in Pigs

          Abstract: Objective To investigate the effects of hepatocyte growth factor(HGF)gene transfected bone marrow mesenchymal stem cells (MSCs)transplantation in pigs with chronic ischemic heart disease. Methods MSCs were isolated from pig bone marrow by density gradient centrifugation and adherent cell culture, purified, and determined by cellsurface antigens(CD34, CD44, CD71, Ⅷ factor and desmin). MSCs were transfected by adenovirus expressing hepatocyte growth factor(AdHGF), and the influence of HGF on the biological characteristics of MSCs was tested. The pig model of chronic myocardial ischemia was established by placing Ameroid ring inside the left circumflex coronary artery via leftthoracotomy. A total of 40 pigs were randomly divided into 5 groups (n=8) and were injected 5×106/ml MSCs+ 4×109 pfu 200 μl AdHGF (MSCs+ AdHGF group), 4×109 pfu 200 μl AdHGF (AdHGF group), 5×106/ml MSCs 200 μl(MSCs group),4×109 pfu 200 μl AdNull (AdNull group)and 1 ml saline(control group) into the ischemic myocardiumrespectively. Echocardiogram, digital subtraction angiography (DSA) of coronary artery, single photon emission computed tomography(SPECT) myocardial perfusion imaging and cardiomyocyte apoptosis were examined after 4 weeks. Results Positive CD44 and CD71 and negative CD34, Ⅷ factorand desmin were detected in MSCs by flow cytometer. HGF had a b influence on stimulating the proliferation and differentiation of MSCs. Echocardiogram examination showed that left ventricular end-diastolic volume(LVEDV),left ventricular ejection fraction(LVEF),fractional shortening(FS)of MSCs+ AdHGF group were significantly increased after treatment (P< 0.05). DSA detection showed that ischemic neovascularization of MSCs+ AdHGF group was significantly higher than those of AdHGF group and MSCs group (P< 0.05). SPECT showed that the left ventricular myocardium of MSCs+ AdHGF group appeared thickened,myocardial perfusion was significantly improved and the myocardial motion was significantly increased (P< 0.05). Vascular density of MSCs+ AdHGF group was significantly higher than those of AdHGF group and MSCs group by HE stain of myocardium [(39.4±1.2)/ HPF vs. (36.5±1.4)/ HPF and(34.5±1.7)/ HPF,P< 0.05]. Cardiomyocyte apoptosis rate of MSCs+ AdHGF group was significantly lower than those of AdHGF group and MSCs group by TUNEL stain (P< 0.05). Conclusion Combination transplantation can promote the angiogenesis of chronic ischemic myocardium, inhibit cardiomyocyte apoptosis and improve heart function in pigs with chronic ischemic heart disease. The effect of HGF gene transfected MSCs transplantation is better than that of MSCs or HGF transplantation alone.

          Release date:2016-08-30 05:50 Export PDF Favorites Scan
        • Progress in Early Diagnosis and Treatment of Severe Heart and Great Vessel Injury

          Severe heart and great vessel injuries were a fatal traumatic entity. How to improve the survival rate of these victims still was a challenge to date. This paper included: the pathogenesis and resuscitation of commotio eordis ; traumatic pericardial rupture associated with heart luxation and/or diaphragmatocele in pericardial cavity; indication selection of emergency room thoracotomy for severe heart injury and traumatic aortic disruption treated with endovascular stent graft. For the purpose of increasing our recognition of the severe trauma and making the early diagnosis and management as early as possible. The main relative references published in recently 5 years were reviewed.

          Release date:2016-08-30 06:22 Export PDF Favorites Scan
        • In vitro experience in tissue engineering heart valve with poly-hydroxybutyrate-co-hydroxyvalerate

          Objective To evaluate the feasibility to fabricate tissue engineered heart valve leaflet with poly hydroxybutyrate co hydroxyvalerate (PHBV) scaffold. Methods Constructive characteristics of PHBV were observed by scanning electron microscope. PHBV was implanted subcutaneously in rabbit and extirpated at 2,4,6,8, and 10 weeks in order to study its biocompatibility and biodegradability. Cell growth curve, smooth muscle α actin and ultra microscopic characteristics were observed in canine aortic valve interstitial cells. The cells were seeded on the PHBV and their function of prostaglandin I 2 (PGI 2) synthesis was determined. Results Porous diameter of PHBV was 130μm, PHBV had good biocompatibility and completely degraded at the end of the 10th week. Smooth muscle α actin were expressed in canine aortic valve interstitial cells and grew well. Cells implanted on PHBV grew well, PGI 2 were synthesized and secreted( P lt;0.05). Conclusion It is feasible to fabricate a tissue engineering heart valve leaflet in vitro with PHBV scaffold.

          Release date:2016-08-30 06:27 Export PDF Favorites Scan
        • Research on bark-frequency spectral coefficients heart sound classification algorithm based on multiple window time-frequency reassignment

          The multi-window time-frequency reassignment helps to improve the time-frequency resolution of bark-frequency spectral coefficient (BFSC) analysis of heart sounds. For this purpose, a new heart sound classification algorithm combining feature extraction based on multi-window time-frequency reassignment BFSC with deep learning was proposed in this paper. Firstly, the randomly intercepted heart sound segments are preprocessed with amplitude normalization, the heart sounds were framed and time-frequency rearrangement based on short-time Fourier transforms were computed using multiple orthogonal windows. A smooth spectrum estimate is calculated by arithmetic averaging each of the obtained independent spectra. Finally, the BFSC of reassignment spectrum is extracted as a feature by the Bark filter bank. In this paper, convolutional network and recurrent neural network are used as classifiers for model comparison and performance evaluation of the extracted features. Eventually, the multi-window time-frequency rearrangement improved BFSC method extracts more discriminative features, with a binary classification accuracy of 0.936, a sensitivity of 0.946, and a specificity of 0.922. These results present that the algorithm proposed in this paper does not need to segment the heart sounds and randomly intercepts the heart sound segments, which greatly simplifies the computational process and is expected to be used for screening of congenital heart disease.

          Release date:2024-04-24 09:40 Export PDF Favorites Scan
        • Detection method of early heart valve diseases based on heart sound features

          Heart valve disease (HVD) is one of the common cardiovascular diseases. Heart sound is an important physiological signal for diagnosing HVDs. This paper proposed a model based on combination of basic component features and envelope autocorrelation features to detect early HVDs. Initially, heart sound signals lasting 5 minutes were denoised by empirical mode decomposition (EMD) algorithm and segmented. Then the basic component features and envelope autocorrelation features of heart sound segments were extracted to construct heart sound feature set. Then the max-relevance and min-redundancy (MRMR) algorithm was utilized to select the optimal mixed feature subset. Finally, decision tree, support vector machine (SVM) and k-nearest neighbor (KNN) classifiers were trained to detect the early HVDs from the normal heart sounds and obtained the best accuracy of 99.9% in clinical database. Normal valve, abnormal semilunar valve and abnormal atrioventricular valve heart sounds were classified and the best accuracy was 99.8%. Moreover, normal valve, single-valve abnormal and multi-valve abnormal heart sounds were classified and the best accuracy was 98.2%. In public database, this method also obtained the good overall accuracy. The result demonstrated this proposed method had important value for the clinical diagnosis of early HVDs.

          Release date:2023-12-21 03:53 Export PDF Favorites Scan
        • The Development of an Animal Model of Cyanotic Heart Diseases

          Abstract:  The cyanotic congenital heart defect remains a focal point to study in congenital heart diseases. A successfully developed model of cyanotic congenital heart defect can contribute to a profound advancement of clinical diagnosis and treatment. Various kinds of animal models simulating cyanotic heart diseases have been created and improved step by step , such as experimental pulmonary arteriovenous fistulas, inferior vena cava-left atrium shunt, pulmonary artery-left atrium shunt and breeding animals in mionect ic environment. As an important means, they are used to investigate the animal’s pathophysilolgocal characteristics in cyanotic and hypoxic state. However, it need a further exploration since these models are not fully perfect yet.

          Release date:2016-08-30 06:08 Export PDF Favorites Scan
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          2. 射丝袜