Dahle, Gry

Abstract Aims Transcatheter mitral valve replacement (TMVR) with the Tendyne Mitral Valve System is a treatment option for patients with severe symptomatic mitral regurgitation (MR) unsuitable for conventional mitral valve surgery or transcatheter edge-to-edge repair (TEER). This study sought to evaluate the safety and effectiveness of TMVR through 5-year follow-up. Methods and Results The Tendyne Expanded Clinical Study is a prospective, single-arm, multicentre study that enrolled patients between November 2014 and June 2020. The study enrolled 191 patients (mean age 74.1 ± 8.0 years, 62.8% male, 70.2% New York Heart Association Class (NYHA) class III/IV, 88.5% secondary MR), of whom 186 (97.4%) underwent TMVR with Tendyne. MR grade decreased from ≥3+ in 99.5% patients at baseline to grade ≤1+ in 95.3% at 5 years. In those patients surviving to 5 years (n = 49), durable symptomatic improvement was evidenced by 73.5% patients being in NYHA class I/II at 5 years. The Kansas City Cardiomyopathy Questionnaire overall summary score increased from 48.5 ± 22.5 points at baseline to 67.6 ± 21.5 points at 5 years. Serious adverse events that occurred through 5 years included life-threatening bleeding (11.5%), fatal bleeding (2.6%), renal insufficiency/failure (28.8%), endocarditis (7.3%), device thrombosis (5.8%), and new onset atrial fibrillation (13.1%). No structural device degeneration or device embolism occurred through 5 years. Conclusions The Tendyne TMVR was effective at achieving immediate and sustainable elimination of MR, which was associated with symptomatic improvement and absence of structural valve degeneration in a high-risk cohort over 5 years. These findings support TMVR with the Tendyne System as an alternative for patients with appropriate mitral valve anatomy and symptomatic secondary MR unsuitable for mitral surgery or TEER.

Bioprostheses are prone to structural valve degeneration, resulting in limited long-term durability. A significant challenge when comparing the durability of different types of bioprostheses is the lack of a standardized terminology for the definition of a degenerated valve. This issue becomes especially important when we try to compare the degeneration rate of surgically inserted and transcatheter bioprosthetic valves. This document, by the VIVID (Valve-in-Valve International Data), proposes practical and standardized definitions of valve degeneration and provides recommendations for the timing of clinical and imaging follow-up assessments accordingly. Its goal is to improve the quality of research and clinical care for patients with deteriorated bioprostheses by providing objective and strict criteria that can be utilized in future clinical trials. We hope that the adoption of these criteria by both the cardiological and surgical communities will lead to improved comparability and interpretation of durability analyses.