Objective To analyze and explore the risk factors of secondary tricuspid regurgitation (TR) after left-sided valve surgery (left cardiac valve replacement or valvuloplasty) using meta-analysis, so as to provide evidence for clinical diagnosis and treatment of secondary TR. Methods We electronically searched databases including PubMed, MEDLINE, CBM, CNKI, VIP, for literature on the risk factors of secondary TR after left-sided valve surgery from 1995 to 2012. According to the inclusion and exclusion criteria, we screened literature, extracted data, and assessed methodological quality. Then, meta-analysis was performed using RevMan 5.0 software. Results A total of 6 case-control studies were included, involving 437 patients and 2 102 controls. The results of meta-analysis showed that, the risk factors of progressive exacerbation of secondary TR after left-sided valve surgery included preoperative atrial fibrillation (OR=3.90, 95%CI 3.00 to 5.07; adjusted OR=3.04, 95%CI 2.21 to 4.16), age (MD=5.36, 95%CI 3.49 to 7.23), huge left atrium (OR=5.17, 95%CI 3.12 to 8.57; adjusted OR=1.91, 95%CI 1.49 to 2.44) or left atrium diameter (MD=4.85, 95%CI 3.18 to 6.53), degradation of left heart function (OR=2.97, 95%CI 1.73 to 5.08), rheumatic pathological change (OR=3.06, 95%CI 1.66 to 4.68), preoperative TR no less than 2+ (OR=3.52, 95%CI 1.26 to 9.89), and mitral valve replacement (MVR) (OR=2.35, 95%CI 1.68 to 3.30). Sex (OR=1.54, 95%CI 0.94 to 2.52) and preoperative pulmonary arterial hypertension (OR=1.28, 95%CI 0.77 to 2.12) were not associated with secondary TR after left-sided valve surgery. Conclusion The risk factors of progressive exacerbation of secondary TR after left-sided valve surgery include preoperative atrial fibrillation, age, huge left atrium or left atrium diameter, degradation of left heart function, rheumatic pathological change, preoperative TR no less than 2+, and MVR. Understanding these risk factors helps us to improve the long-time effectiveness of preventing and treating TR after left-sided valve surgery.
Objective To develop a tissue engineering scaffold by using 4arm branched polyethylene glycol-VS (PEG-VS) crosslinked with decellularized valved conduits (DVC), and to research on its mechanical and biological functions. Methods The valved aortic conduits of rabbits were taken and decellularized by trypsin method and then were crosslinked with 4arm branched PEG-VS to construct the composite scaffolds (CS). The functions of decellularized valved conduits and the composite scaffolds were tested by mechanics test system. Thirty New Zealand white rabbits were equally and randomly assigned to one of the three groups: the control group, the DVC group, and the CS group. Valved aortic conduits, decellularized valved conduits and composite scaffoldswere transplanted into the common carotid artery of the abovementioned three groups of rabbits respectively. Twentyeight days after the operation, patency of the transplants was tested by Color Doppler ultrasound; micromorphology and inflammatory infiltration were observed by hematoxylin eosin（HE） staining andscanning electron microscope (SEM)，and endothelialization of composite scaffolds was detected by immunofluorescent staining. Results A series of biomechanical analyses revealed that the composite scaffolds had highly similar mechanical properties as fresh tissue, and had superior elastic modulus (P=3.1×10-9) and tensile strength (P=1.1×10-6) compared with decellularized valved conduits. Color Doppler ultrasound revealed that the graft patency for the CS group was better than the control group (P=0.054) and the DVC group (P=0.019), and the intraaortic thrombosis rate and distortion rate decreased significantly. HE staining and SEM showed that the endothelialization of composite scaffolds in the CS group was significantly higher than the other two groups with the endothelial cells evenly distributed on the scaffolds. The [CM(159mm]immunofluorescent staining indicated that the positive rate of the endothelial cell marker CD34 was higher than the other two groups. Conclusion The composite scaffolds using 4arm branched PEGVS crosslinked with DVC have great mechanical and biological properties.
Abstract: Objective To induce calcification in aortic valvular interstitial cells (VICs) in vitro and observe the shift of cellular phenotype during the process. Methods Porcine aortic VICs were isolated and expanded by collagenase methods. Fluorescent staining was performed to identify the interstitial cells. VICs at 48 passages were used for experiments. The cells were divided into two groups: the experimental group in which cells were cultured in osteogenic media supplemented with βglycerophosphate, vitamin C and dexamethasone, and the control group in which cells were cultured in normal media. After 2 weeks, calcified nodules were quantified. Calcium deposit was stained and measured by Alizarin Red S staining and assay. Real time reverse transcription polymerase chain reaction (RTPCR) was performed to measure expression of alpha smooth muscle actin (α-SMA) and calcification related factors such as osteocalcin, osteopontin and Corebinding factor α1/Runx2 (Cbfα1/Runx2). Results VICs were successfully harvested from porcine aortic valves, identified by positive staining of α-SMA, vimentin and negative staining of Von Willebrand factor (vWF). VICs could calcify after 2 weeks of osteogenic induction with calcified nodules formed. Quantification of calcified nodules and calcification deposit were significantly higher (Plt;0.05) in the experimental group than those in the control group (156.25±17.38 vs. 2.50±1.29, 17.52±2.04 vs. 1.00±0.22). Real Time RT-PCR indicated that expression of α-SMA, as well as calcification related markers like osteocalcin, osteopontin and Cbfα1/Runx2 was much higher in the experimental group than those in the control group (Plt;0.05). Conclusion VICs are activated during the progress of calcification with phenotype shifting to contraction and ossification, which might be the pathological basis of valvular calcification.
Abstract: Objective Using Amplex red fluorometric assay to detect the lysyl oxidase (LOX) enzyme activity in tissue engineered heart valve (TEHV). Methods Porcine aortic valves were decellularized with trypsin+ethylene diaminetetraacetic acid(EDTA), TritonX-100, and RNaseⅠ＋DNaseⅠ, then they were seeded by myo-fibroblasts that harvested from rats. Then they were fed with Dulbecco’s modified Eagle medium (DMEM) which contained high glucose for 27 days, they were fed with phenol red-free and serumfree DMEM for 24 hours, and the medium was harvested and used for LOX enzyme activity assays with the Amplex red fluorometric assay. And reverse transcription-polymerase chain reaction (RT-PCR) technique was used to analyze the expression of LOXmRNA in TEHV. Results All the samples produced measurable amounts of active LOX enzyme. The fluorescence units were 45.60±1.66, and the corresponding concentration of LOX enzyme were 0.123±0.003μg/ml. At the same time, all the samples expressed LOXmRNA. The expression of LOXmRNA was corresponding to the results of the Amplex red fluorometric assay. Conclusion It is feasible to detect the LOX enzyme activity in TEHV with the Amplex red fluorometric assay. And this assay gives a way to reflect that LOX plays an important role in collagen cross-linking of extracellar matrix in TEHV.
Objective To observe whether Cyclo-RGDfK (Arg-Gly-Asp-D-Phe-Lys) could enhance the adhesion of myofibroblast to decellularized scaffolds and upregulate the expression of Integrin αVβ3 gene. Methods Myofibroblast from the rat thoracic aorta was acquired by primary cell culture. The expression of Vimentin and α-smooth muscle actin(α-SMA) has been detected by immunoflurescent labeling. Decellularized valves have been randomly divided into three groups (each n=7). Group A (blank control): valves do not receive any pretreatment; Group B: valves reacted with linking agent NEthylN(3dimethylaminopropyl)carbodiimide hydrochloride (EDC) for 36 hours before being seeded; Experimental group: Cyclo-RGD peptide has been covalently immobilized onto the surface of scaffolds by linking agent EDC. The fifth generation of myofibroblast has been planted on the scaffolds of each group. The adhesion of myofibroblast to the scaffolds was evaluated by HE staining and electron scanning microscope. The expression of Integrin αVβ3 was quantified by halfquantitative reverse transcriptionpolymerase china reaction (RT-PCR). Results We can see that myofibroblast has exhibited b positive staining for Vimentin and α-SMA. Besides, it has been shown that the expression of Integrin αVβ3 was much higher in the experimental group than that of the group A and group B(Plt;0.05). There was no statistically difference in group A and group B (P=0.900). Conclusion RGD pretreatment does enhance the adhesive efficiency of seeding cells to the scaffolds and this effect may be related to the upregulation of Integrin αVβ3.
With the development of social economy and medicine, degenerative heart valve disease has become the major part in heart valve disease. Calcific aortic valve disease (CAVD) is one of the most representative manifestations of degenerative valvular disease. Aortic valve calcification (AVC) has been found to be a strong predictor of major cardiovascular events, which makes it necessary to identify an effective way to evaluate the degree of AVC. Numerous methods of quantitative assessment of AVC have been reported. Here, we discuss these methods from the aspects of pathology and imageology.
Infective endocarditis (IE) is a disease with severe complications and high mortality. It is heterogeneous in etiology, clinical manifestations, and course. At the same time, there are many disputes on the clinical practice of antibiotic treatment, surgical indications and timing. In this review, we discuss the epidemiology, diagnosis, treatment, and prevention of IE, especially the latest advances in surgical treatment after the release of European Society of Cardiology and American Heart Association guidelines in 2015.
In recent years, the number of interventions for valvular heart disease has been increasing day by day, and it has become a hot topic in the field of cardiovascular surgery. Given the aging global population and trends in the prevalence of valvular disease and the broadening of indications for transcatheter aortic valve replacement (TAVR), a breakthrough of 130000 TAVR procedures is expected by 2026. In the new technology development period, the development potential and technical advantages of heart valve interventional therapy should be faced squarely. This paper focuses on key issues such as comparison of outcomes after TAVR versus surgical aortic valve replacement (SAVR), prosthetic valve endocarditis after TAVR, and broadening of indications for TAVR, as well as recommendations on how surgeons face the era of TAVR. We hope that this article will help and attract the attention of cardiac surgeons.
Valve transplantation is often used in the treatment of aortic valve insufficiency. However, after surgery, the reconstructed aortic roots have an expansion phenomenon, in which the lack of valve height causes the aortic valve to close again. In this paper, the effects of different aortic valve height design on valve opening and closing performance were studied. The optimal surgical plan was obtained by in vitro numerical simulation, providing technical support and theoretical basis. In this paper, six groups of three-dimensional geometric models with a valve height increment of ± 0.5 mm were established with a root diameter of 26.0 mm and a valve height of 14.0 mm. Through the structural mechanics calculation and analysis of the parameters such as maximum stress, valve area and contact force of the model, reasonable geometrical dimensions are obtained. The study found that the maximum stress values of the six groups of models ranged from 640 to 690 kPa, which was consistent with the results of the literature; the three-group models with valve heights of 13.5 mm, 14.0 mm, and 14.5 mm were within a reasonable range. The contact force value of the 6 groups of leaflets increased with the increase of valve height. Studies have shown that the height of the aortic valve has an effect on the aortic valve closure performance. A valve height that is too small or too large will reduce the aortic systolic valve area and affect the aortic function.
Implantable left ventricular assist device (LVAD) has become an essential treatment for end-stage heart failure, and its effect has been continuously improved. In the world, magnetic levitation LVAD has become mainstream and is increasingly used as a destination treatment. China has also entered the era of ventricular assist device. The continuous improvement of the ventricular assist device will further improve the treatment effect. This article reviews the current situation and development trend of LVAD treatment in China and abroad.