Predictors for NYHA recovery and 1-year mortality after mitral TEER
Authors: Santos Ferreira D A , Guerreiro C , Diaz S , Silva G , Moura A R , Pereira E , Sampaio F , Nunes F , Teixeira R , Santos L , Rodrigues A , Braga P , Pires-Morais G , Melica B , Fontes-Carvalho R 
Published: October 2022

Abstract

Background
Mitral regurgitation (MR) is the second-most frequent valvular heart disease in Europe and frequently aggravates heart failure (HF) symptoms. Mitral transcatheter-edge-to-edge repair (TEER) can be considered in eligible patients, for both primary (in inoperable cases) or secondary severe MR. However, intervention is not advised in severe comorbid patients in whom it is not expected to prolong survival for over 1 year.

Purpose
Evaluate characteristics associated with HF New York Heart Association (NYHA) class recovery, and one-year all-cause mortality after mitral TEER for severe MR.

Methods
All mitral TEER procedures for primary and secondary MR conducted in a single-centre between 2014 and 2020 were retrospectively analyzed. The primary endpoint was defined as a reduction of at least one NYHA class in the first month after intervention, and a secondary endpoint considered a recovery of at least two NYHA classes. Survival status 12 months after mitral TEER was also consulted. Clinical, echocardiographic and blood-analysis data were explored as characteristics associated with the endpoints defined, using Pearson's Chi-squared test, Wilcoxon rank sum test and Fisher's exact test, as appropriate. A p&lt;0.05 was considered statistically significant.

Results
From 103 mitral TEER procedures, 86 (83%) had full information about pre- and post-intervention NYHA class, as well as survival status at 12 months. There was a higher proportion of primary MR among NYHA non-responders (47% versus 25%, p=0.034), but no differences for secondary MR. Higher surgical risk patients (EuroSCORE II) tended to have exhibit more NYHA recovery, though not reaching statistical significance (p=0.068). Both a more advanced NYHA class at baseline and lower N-terminal pro-brain natriuretic peptide (NTproBNP) levels were linked to a higher symptomatic recovery (2048 versus 5676pg/ml, p&lt;0.001). Also, persisting MR after TEER of at least grade 3/4 was more frequent in non-NYHA responders. Regarding NYHA improvement of at least two classes, it was observed in 13% patients, and these also had a more advanced NYHA class at baseline and lower NTproBNP basal levels, and exhibited a lower estimated systolic pulmonary artery pressure and inferior vena cava (IVC) diameter. Finally, 10 (11.6%) of mitral TEER patients died in the first 12 months, and no statistically significant associations were found regarding pre-intervention characteristics and survival.

Conclusions
This study suggests that three-fifths of severe MR improve their NYHA class after TEER, but only one-fourth for primary MR. Earlier intervention – with lower NTproBNP levels, less severe pulmonary hypertension, and lower IVC diameters – is associated with more symptomatic HF improvement. All-cause mortality in the first year is still significant, exposing a need for better patient selection. However, these findings represent exploratory deductions of a relatively low number, single-centre, patients.

Funding Acknowledgement
Type of funding sources: None.