Transcatheter aortic valve replacement (TAVR) as a mature technology has been widely applied in Western countries. In China, with the first two domestic prostheses being approved for commercial use, the technology now is expecting a fast development. In this article, we reviewed the features of Chinese aortic stenosis patients, the early Chinese experience of TAVR, the application of domestic prostheses and remaining problems.
In 2020, due to the impact of the novel coronavirus epidemic, the development of transcatheter heart valve therapy has been shown to slow down, but there are still many aspects worth noting. The indication of monoclonal antibody after transcatheter aortic valve replacement (TAVR) should be further clarified. Low surgical risk patients were included in TAVR relative indications. Mitraclip G4 was approved by CE. The indication of atrial septal occlusion after mitraclip should be further clarified. The technique of coaptation augmentation is expected to become a new method of mitral valve interventional repair. Tendyne transcatheter mitral valve was approved by European Union. Transcatheter tricuspid valve treatment equipments, TriClip and PASCAL obtained CE mark. TAVR technology is being popularized rapidly in China, and what’s more, balloon dilated valve Sapien 3 and new recyclable repositioning valve system-Venus plus have entered the domestic market. A number of mitral valve therapeutic instruments have appeared one after another, and China's first tricuspid valve lux has completed its FIM research. Finally, with the improvement of devices and technology in the future, interventional therapy of heart valve is expected to benefit more patients.
Mitral regurgitation (MR) is the most common heart valve disease. In recent years, the rise of interventional therapy has expanded the indications of interventional treatment for patients with MR, but the epidemiological characteristics of MR (especially the number of patients with MR requiring treatment) in China are still unclear. In this paper, we analyzed and estimated the number of MR patients in China based on three epidemiological studies in Europe and America, and referring to the patients population surveys from Zhongshan Hospital Affiliated to Fudan University, the Second Affiliated Hospital Zhejiang University School of Medicine and Beijing Fuwai Hospital. Our analysis estimated that about 7.5 million patients with MR need intervention in China, including about 5.5 million patients with severe MR.
Atrial functional mitral regurgitation has been referred to patients with atrial fibrillation related functional mitral regurgitation without left ventricular dysfunction and it has nowadays received remarked attention in structural heart disease field. Significant dilation of mitral annulus and left atrium, insufficient leaflet remodeling, iatrogenic leaflet tethering, reduced annular contractility and increased valve stress by flattened saddle shape of the annulus might be important triggers of atrial functional mitral regurgitation. Recently, several studies indicated that transcatheter edge-to-edge mitral valve repair could be an effective strategy for atrial functional mitral regurgitation. In this review, the definition, mechanism together with efficacy and safety of transcatheter edge-to-edge mitral valve repair in atrial functional mitral regurgitation are discussed.
Transcatheter edge-to-edge repair (TEER) originated from surgical edge-to-edge repair. MitraClip is the first mature TEER device, and the TEER based on MitraClip is far ahead of many transcatheter mitral valve repair (TMVr) technologies in terms of safety, effectiveness and popularity, so it is named separately in the latest guidelines. The TEER has the following advantages: consistent with basic medical principles, few implants, precise target, less invasive and repeatable. However, there are also some shortcomings, such as the relatively complex design of transfemoral device, target single and relatively narrow indications. At present, the main clinical data of TEER are mainly from the clinical practice of MitraClip. Based on the three-year outcomes of COAPT study, both 2020 ACC/AHA guideline and 2020 ACC expert consensus decision pathway on the management of mitral regurgitation recommend in patients with chronic heart failure with left ventricular dysfunction and severe mitral regurgitation in nonresponders to medicine treatment. Edward's PASCAL, another TEER device, has two models. Among the domestic TEER devices, the ValveClamp of Hanyu medical technology has many distinct advantages, such as simple operation, large clamping area, high clamping efficiency and no need of X-ray. DragonFly, another domestic TEER device, has also completed its feasibility study. There are five trends of TEER in the future: further expansion of indications, combination with other interventional techniques, repeatable operations, transcatheter mitral valve replacement after TEER, and continuous improvement and innovation of equipment.
Mitral regurgitation is one of the most common heart valve diseases. Transcatheter edge-to-edge repair (TEER) is currently the most developed and commonly used interventional technique for mitral regurgitation and is recommended by the latest European and American guidelines for patients who are at high surgical risk. TEER device usually consists of a clamping device and a delivery system. The trajectory of the clamping device is called the trajectory, and the trajectory can be well established with the five dimensions movement of the delivery system: left-right oscillation, anterior-posterior oscillation, overall parallel movement, the clamping device's own clockwise rotation, and vertical up-and-down movement. The delivery system's anteroposterior and lateral oscillations are concentrated on the virtual puncture site. Furthermore, the location of the septal puncture site has a significant impact on the establishemnt of the trajectory. The evulation of three variables and adherence to the "4M principles" are necessary for the successful TEER. The three variables are: the position of the clip in the center of the regurgitation,the arm orientation of the clip perpendicular to the boundary of anterior and posterior leaflets, as well as the appropriate length of clamping. The "4M principles" include favorable valve morphology, residual mitral regurgitation below grade 2+, mean transvalvular pressure≤5 mm Hg, and an appropriate amount of leaflets clamping. Patients' baseline situation, the degree of mitral regurgitation and ventricular remodeling, as well as the valve morphology and the outcome of the procedure, are the factors determining the prognosis of patients after TEER.
Transcatheter edge-to-edge repair (TEER) for mitral regurgitation (MR) is known as M-TEER. Its strengths include: precise targets and fewer implants; simple and clear principles for catheterization; originating from dependable medical concepts and broad applicability. Furthermore, TEER offers advantages in real-time hemodynamic and effectiveness measurement throughout the procedure over surgical edge-to-edge repair (SEER). When it comes to patients with degenerative mitral regurgitation , M-TEER should aim to deliver more optimum procedural outcomes. In functional mitral regurgitation, a modest transvalvular gradients or moderate residual shunt can be tolerated with M-TEER, which reduces the risk of problems and has no bearing on the patient's prognosis.
Mitral regurgitation (MR) is a kind of valvular heart disease with a complicated pathogenesis. However, the current clinical understanding of MR mostly stays in a purely spatial perspective. We suggest that the evaluation of MR should break through the limited thinking of the area of a two-dimensional single frame, and transfer to a comprehensive evaluation of three-dimensional space-time integration (i.e. four-dimensional space-time). Secondly, it is of significance to pay attention to the time mechanism and time thinking of the occurrence of MR. The amount of MR may be different in different cardiac cycles or within the same cardiac cycle. Finally, changes in the time dimension of cardiac contraction can lead to the occurrence of MR and sometimes it is necessary to understand MR from time thinking rather than spatial thinking.
ObjectiveTo study the hemocompatibility of bioprosthetic heart valve materials respectively based on glutaraldehyde and non-glutaraldehyde treatment. MethodsFresh bovine pericardium was treated with glutaraldehyde or non-glutaraldehyde after adipose tissue was removed. To evaluate the hemocompatibility of the two bioprosthetic heart valve materials, hemolysis test, in vitro fibrinogen adsorption experiment, platelet adhesion experiment, thrombin-antithrombin complex (TAT) test, complement activation assay and ex vivo circulation experiment were performed. ResultsThe hemolysis test results demonstrated that both of the materials showed hemolytic rates lower than 5%. The results of TAT test and complement activation assay showed no statistical differences among the two materials and the blank control group. Compared to the bioprosthetic heart valve materials with glutaraldehyde-based treatment, the materials with non-glutaraldehyde-based treatment showed significantly decreased fibrinogen adsorption, platelet adhesion and thrombosis. ConclusionCompared to the bioprosthetic heart valve materials with glutaraldehyde-based treatment, the materials with non-glutaraldehyde-based treatment show better hemocompatibility.
Transcatheter mitral valve edge-to-edge repair (TEER) has become an important treatment opinion for patients with severe mitral regurgitation (MR) at high risk for surgery. The devices and procedural techniques of TEER are complex and require excellent team cooperation. However, there is still a lack of standardized clinical pathways in China. Based on the latest evidence, the expert group wrote this clinical pathway to guide and optimize TEER therapy in clinical practice. It demonstrates the following key issues of clinical concern: (1) TEER team building; (2) preoperative clinical evaluation of TEER patients; (3) imaging assessment before TEER procedure; (4) standardized procedures for TEER; (5) TEER for complex MR; (6) the standard process of perioperative comprehensive management; and (7) full life-cycle rehabilitation and follow-up. This clinical pathway might be helpful to facilitate the standardized development of TEER therapy and application, and promote the improvement of management and life quality for patients with MR.