490 Right ventricular free wall longitudinal strain negatively impacts prognosis of patients with functional mitral regurgitation undergoing transcatheter edge-to-edge mitral valve repair
Authors: Iuliano Giuseppe , Silverio Angelo , Baldi Cesare , Bellino Michele , Esposito Luca , Di Feo Federica , Cristiano Mario , Radano Ilaria , Maiellaro Francesco , Provenza Gennaro , Ciccarelli Michele , Galasso Gennaro , Vecchione Carmine , Citro Rodolfo 
Published: December 2021

Abstract

Aims
Although right ventricular (RV) systolic dysfunction seems to be associated with adverse outcome after transcatheter edge-to-edge mitral valve repair (TEER) with the MitraClip system, the prognostic value of RV free wall longitudinal strain (RVFWLS) in this setting has not been yet investigated. The aim of this study is to evaluate RVFWLS as predictor of outcome in patients with severe or moderate-to-severe functional MR undergoing TEER and its prognostic role compared with tricuspid annular plane systolic excursion (TAPSE).

Methods and results
102 patients [73 (IQR: 66.8–77.0) years, 73 males (71.6%)] were retrospectively selected from March 2012 to February 2021. Echocardiograms were performed by using General Electric machines. RVFWLS was assessed through RV modified apical 4-chamber view, setting the region of interest to minimum size. Values of RVFWLS &gt; −20% were recognized as abnormal. We considered a composite endpoint including rehospitalization for heart failure (HF) and overall death as primary outcome. Secondary outcomes were overall death, cardiac death and rehospitalization for HF. All patients were assessed at the longest available follow-up [median 22.1 (IQR: 9.7–49.3) months]. Baseline clinical and echocardiographic characteristics are listed in Table 1. Primary outcome was found in 60 (58.8%) patients, while secondary outcomes, i.e. overall death, cardiac death and rehospitalization for HF, were found respectively in 50 (50.0%), 31 (30.4%), and 36 (35.3%) patients. Mean TAPSE was 16.7 ± 4.0 mm and mean RVFWLS was −16.9 ± 6.0%. At univariable analysis both TAPSE (HR: 0.907, CI: 0.848–0.970, P-value: 0.004) and RVFWLS (HR: 0.937, CI: 0.897–0.979, P-value: 0.004) were significantly associated with the primary outcome. Kaplan–Meier survival curves showed that patients with TAPSE &lt;17 mm had a lower survival free from the composite outcome compared with those with TAPSE ≥17 mm (Log-Rank = 0.030); patients with RVFWLS value &gt; −20% also showed a lower survival free from the composite outcome compared with patients with RVFWLS ≤ −20% (Log Rank 0.004). Among patients with preserved RV systolic longitudinal function as indicated by TAPSE ≥ 17 mm, subjects with RVFWLS &gt; −20% had a significantly higher incidence of the composite outcome compare with those with RVFWLS ≤ −20% (Log-Rank = 0.008). Conversely, no difference was found among patients with TAPSE &lt;17 mm.

Conclusions
RV dysfunction assessed either by TAPSE and RVFWLS is associated with poorer outcome in patients with severe or moderate-to-severe functional MR undergoing TEER. Compared with TAPSE, RVFWLS seems to be superior in identifying patients at higher risk of adverse events during follow-up. Our data encourage the use of this speckle tracking-derived echocardiographic parameter in routinely evaluation of patients with functional MR candidate for TEER.