Management of patients with mitral regurgitation ineligible for standard therapy undergoing TMVI screening.

BACKGROUND: Transcatheter mitral valve implantation (TMVI) represents a novel treatment alternative for patients with severe mitral regurgitation (MR) considered ineligible for standard therapies. Data on the management of patients after TMVI screening are scarce. AIMS: We aimed to investigate outcomes of patients with severe MR undergoing TMVI evaluation treated with either TMVI, bailout-transcatheter edge-to-edge repair (bailout-TEER) or medical therapy (MT). METHODS: Between May 2016 and February 2021, 121 patients with MR considered ineligible for standard therapy were screened for TMVI. Outcomes were assessed for the subgroups of patients treated with TMVI, bailout-TEER and MT. The primary composite endpoint was all-cause death or heart failure hospitalisation after one year. RESULTS: The subgroups of TMVI (N=38), bailout-TEER (N=28) and MT (N=44) differed significantly with regard to MR aetiology (secondary MR: TMVI 68.4%, bailout-TEER 39.3%, MT 38.6%, p=0.014) and left ventricular ejection fraction (TMVI 37.0% [31.4-51.2], bailout-TEER 48.0% [35.3-58.3], MT 54.5% [40.8-60.0], p<0.001). At discharge and after one year, MR was reduced to ≤mild residual MR in all patients undergoing TMVI, while ≥moderate residual MR was present in 25.9% and 20.0% of patients, respectively, after bailout-TEER, and in 100.0% of patients on MT at one year. The primary endpoint occurred in 72.2% of patients remaining on MT, in 51.6% of patients undergoing TMVI and in 40.2% of those receiving bailout-TEER. CONCLUSIONS: In MR patients considered ineligible for standard therapy, TMVI provided acceptable clinical outcomes and MR elimination in the majority of patients. In screen-failed patients, bailout-TEER represented a reasonable alternative while MT was associated with poor outcomes.

Characteristics and Outcomes of Patients Ineligible for Transcatheter Mitral Valve Replacement (TMVR): Implications for Future Device Innovation.

OBJECTIVES: Due to high rates of transcatheter mitral valve replacement (TMVR) screening failure, a substantial proportion of patients with severe mitral regurgitation (MR) remains on optimal medical treatment (OMT) only. Data on outcomes of these patients ineligible for mitral interventions are scarce. This study aimed to assess characteristics and outcomes of severe MR patients treated medically following TMVR screening failure. METHODS: From 2016-2020, a total of 111 patients with severe MR underwent screening for TMVR. Screening failure occurred in 66 cases. Among these, 30 patients were treated with OMT only. Characteristics of these patients were analyzed, Kaplan-Meier estimates calculated, and univariate regression analysis performed. Median follow-up time was 2.26 years (95% confidence interval, 1.24-3.25). RESULTS: Anatomical reasons for screening failure in the study cohort (n = 30) were left ventricular (LV) restraints, risk of LV outflow tract obstruction, mitral annulus calcification, and sizing issues. Median ejection fraction was 56.0% (interquartile range, 38.8%-60.0%). Concomitant tricuspid regurgitation and severe pulmonary hypertension were present in 36.7% and 46.2%, respectively. Intercommissural diameters ranged from 22.5-52.0 mm. Mortality was 23.6% after 6 months and 35.7% after 1 year. Factors associated with mortality were female sex, MR severity, ischemic MR, high N-terminal pro-brain natriuretic peptide levels, and small annulus diameters. CONCLUSIONS: Despite growing experience with TMVR, the subset of MR patients anatomically eligible for TMVR is small and many patients are treated medically. Mortality in these patients remains high, underlining an unmet need for adequate therapeutic alternatives. TMVR devices adapting to broader annular size ranges with smaller ventricular profiles might fill this gap.