Mitral valve TEER in the UK: what you need to know as TEER becomes routinely available in the NHS

Abstract

Transcatheter edge-to-edge repair (TEER) was first performed in 2003, and is now established across the developed world as an effective, minimally invasive treatment option for patients with mitral regurgitation (MR). Multiple large registries have established the efficacy of mitral TEER in patients with primary or degenerative MR in whom surgery is considered prohibitive or high risk, while ongoing randomised-controlled trials will determine its role in younger and lower- risk patients. In patients with secondary or functional MR, in whom mitral valve surgery is not routinely recommended, the pivotal COAPT trial showed a profound reduction in both mortality and heart failure hospitalisation in carefully selected patients. NHS England approved the routine commissioning of mitral TEER in 2019, and following a substantial delay, due in large part to the COVID pandemic, the procedure is now widely available across the UK. This review article describes the TEER procedure, currently available devices, the underlying evidence base, and the key facts needed for clinicians to understand who, how, and where to refer patients for consideration of mitral TEER. The emerging role of TEER in patients with severe symptomatic tricuspid regurgitation is also considered.

Keywords: mitral valve; percutaneous mitral valve leaflet repair; transcatheter edge-to-edge repair (TEER); tricuspid valve.

Figure 1.. Transcatheter edge-to-edge repair (TEER) procedure numbers per million population in 2019 in Western Europe

Figure 2.. Mitral valve segmental analysis. A ‘surgical 3D view’ of the mitral valve is shown and illustrates where the cursor (dashed line) of the simultaneous multi-plane image is traversing the aspect of the commissural line of the mitral valve (images A, D and G). Directing the cursor of the simultaneous multi-plane through the relevant scallop on the optimised bi-commissural view in the primary image depicts the corresponding orthogonal long-axis view of the scallops in the secondary image (images B, E and H). The same image with colour Doppler is shown (images C, F and I) to illustrate the jet characteristics. In this case a flail P2 scallop with a large conversion zone is seen due to the regurgitation through the flail P2 scallop

Figure 3.. In degenerative mitral regurgitation (DMR) the flail gap is best measured in the long-axis view (or where the flail gap is greatest) in systole. The mobile leaflet length is measured usually in long-axis either in systole or in mid- diastole (A). The flail width is usually either measured in mitral valve short-axis view in systole or on the 3D en-face view as depicted in image B. In functional mitral regurgitation (FMR) the coaptation depth and coaptation length are best measured in the four-chamber or long-axis view in systole (C and D)