Prognostic Impact of Qualitative and Quantitative Mitral Valve Calcification in Transapical Transcatheter Mitral Valve Replacement: A Sub-Analysis of the TENDER Registry

Objectives: This study aims to review short- to intermediate-term outcomes after transapical transcatheter mitral valve replacement (TMVR) using the Tendyne valve system in patients with mitral annular calcification (MAC), including off-label use in severe MAC. Methods: This retrospective sub-analysis of the multicenter Tendyne European Experience (TENDER) registry included fifty-three MAC patients who underwent commercial Tendyne-TMVR in 15 European heart centers between 01/2020 and 06/2022. Patients were assigned to the mild (n = 16), moderate (n = 17), and severe MAC (n = 20) cohorts according to Guerrero’s MAC score. Additionally, the predictive value of detailed computed tomography-derived, quantitative, and qualitative MAC characteristics on clinical outcome was tested. Results: In this overall multimorbid patient population, predominantly treated for severe mitral regurgitation (MR), technical success rates were comparable among cohorts (mild MAC: 93.8% vs. moderate MAC: 88.2%vs. severe MAC: 95%, p = 0.720). Complete MR abolishment was achieved in 88.7% of patients, with no significant difference between cohorts in the incidence of residual MR >1+ (n = 1 in moderate MAC; p = 0.350) or paravalvular leakage >1+ (PVL; n = 2 in moderate MAC, p = 0.118) at discharge. All three in-hospital deaths occurred in patients with moderate MAC (p = 0.034). There were no significant differences in 1-year cardiovascular mortality (mild MAC: 23.1% vs. moderate MAC: 6.3% vs. severe MAC: 0%, p = 0.085) and overall mortality (mild MAC: 38.5% vs. moderate MAC: 43.8% vs. severe MAC: 18.8%, p = 0.291) between the cohorts, including in patients with off-label severe MAC. The rate of heart failure hospitalization at 1 year was significantly higher in the moderate MAC cohort (mild MAC: 10% vs. moderate MAC: 61.5%, severe MAC: 21.4%, p = 0.017). Further quantitative and qualitative MAC parameters showed no significant impact on 1-year survival or hemodynamic prosthetic performance. Conclusions: This MAC-focused analysis suggests that Valve-in-MAC using the Tendyne valve system is safe, technically feasible, and associated with satisfying hemodynamic and clinical outcomes, irrespective of MAC morphology.