Transcatheter Mitral Valve Intervention for Chronic Mitral Regurgitation: A Plethora of Different Technologies

Numerical modeling for efficiency and endurance assessment of an indirect mitral annuloplasty device

In recent years, several transcatheter systems have been introduced for treatment of common mitral regurgitation (MR). Such a system that is based on indirect mitral annuloplasty (IMA) is currently indicated for functional MR. Very few clinical studies have been performed to assess the efficiency and durability of such devices, despite their high risk of fracture resulting from ongoing exposure to large cyclic deformations. In this study, numerical models of moderate primary MR were created to test the implantation procedure of a customized IMA device and its sealing efficiency. The ability of the implanted device to reduce systolic leakage was evaluated and affirmed with a model of a more generic device. The long-term durability of the device was tested using a range of Nickel Titanium material properties. Our results demonstrated a considerable reduction in leakage for both the simplified generic device and the more detailed customized device models. The device met different fatigue criteria, confirming its resiliency and safety even after 10 years, even under the harsher conditions of primary MR. This is the first study to assess the performance and fatigue risk of IMA devices for the treatment of more complicated MR conditions. These findings may pave the way for further research to ultimately consider the device in selective cases of PMR.

Numerical biomechanics modelling of indirect mitral annuloplasty treatments for functional mitral regurgitation

Mitral valve regurgitation (MR) is a common valvular heart disease where an improper closure leads to leakage from the left ventricle into the left atrium. There is a need for less-invasive treatments such as percutaneous repairs for a large inoperable patient population. The aim of this study is to compare several indirect mitral annuloplasty (IMA) percutaneous repair techniques by finite-element analyses. Two types of generic IMA devices were considered, based on coronary sinus vein shortening (IMA-CS) to reduce the annulus perimeter and based on shortening of the anterior-posterior diameter (IMA-AP). The disease, its treatments, and the heart function post-repair were modelled by modifying the living heart human model (Dassault Systèmes). A functional MR pathology that represents ischaemic MR was generated and the IMA treatments were simulated in it, followed by heart function simulations with the devices and leakage quantification from blood flow simulations. All treatments were able to reduce leakage, the IMA-AP device achieved better sealing, and there was a correlation between the IMA-CS device length and the reduction in leakage. The results of this study can help in bringing IMA-AP to market, expanding the use of IMA devices, and optimizing future designs of such devices.

Comparison of different transcatheter interventions for treatment of mitral regurgitation: A protocol for a network meta-analysis

BACKGROUND

The arrival of transcatheter mitral valve therapies has provided feasible and safe alternatives to medical and surgical treatments for mitral regurgitation. The aim of this study is to estimate the relative efficacy and safety of different transcatheter mitral valve therapies for mitral regurgitation patients through network meta-analysis.

METHODS

A systematic search will be performed using PubMed, EMBASE, the Cochrane Library, Web of Science, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure to include random controlled trials and nonrandom controlled trials comparing the efficacy and safety of different transcatheter mitral valve techniques. The risk of bias for the included nonrandom controlled studies will be evaluated according to Risk of Bias in Non-randomized Studies - of Interventions. For random controlled trials, we will use Cochrane Handbook version 5.1.0 as the risk of bias tool. A Bayesian network meta-analysis will be conducted using R-4.0.3 software. Grading of recommendations assessment, development, and evaluation will be used to assess the quality of evidence.

RESULTS

The results of this network meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This study will provide broad evidence of efficacy and safety of different transcatheter mitral valve therapies for treatment of mitral regurgitation and provide suggestions for clinical practice and future research.

PROTOCOL REGISTRATION NUMBER

INPLASY2020110034.

Transcatheter management of valvular regurgitation beyond the aortic valve (mitral - tricuspid valve): Literature overview and future perspectives

The growth of the available transcatheter treatment approaches for the mitral and tricuspid position was accompanied by important clinical trials and studies through the last years. The selection of appropriate candidates for transcatheter techniques requires significant insight into anatomical limitations of each patient undergoing clinical evaluation. Furthermore, technological characteristics of the available devices, and risks and benefits of each potential therapy, play the most important role in a physician's decision. This knowledge should be valuable to both interventional cardiologists and researchers. This paper aims to offer a concise overview of the technological advances in this field of Interventional Cardiology. Trials and studies announced at the major interventional cardiology congresses during 2018 and 2019 were systematically reviewed. Moreover, a literature search in PubMed for the same period identified an amount of publications eligible for inclusion, based on their relevance to the subject, and their potential impact on current guidelines of good clinical practice.