425 Alterations in left atrial structure and function in chronic heart failure patients with functional mitral regurgitation after MitraClip

Abstract

Backround The MitraClip procedure has been increasingly performed as an established treatment alternative for symptomatic patients with moderate to severe mitral regurgitation (MR) at prohibitive surgical risk. Left ventricular (LV) reverse remodelling following MitraClip has been shown in different studies. Left atrial (LA) volumes are believed to decrease following interventional reduction of MR. However, effects of MitraClip on LA function are not well understood. Objectives In this study we aimed to evaluate the effect of MitraClip on LA structure, volumes and function in chronic heart failure patients with functional MR. Methods All patients underwent 3D transthoracic echocardiography prior to the MitraClip procedure and at follow-up (FU) with offline evaluation of LA function and geometry using dedicated software (TomTec Image Arena, 4D LV-Analysis, Munich, Germany). FU examinations were performed 10 ± 3.4 months after the procedure. Results We prospectively included 75 consecutive surgical high risk (Logistic EuroScore: 17.2 ± 13.9%) patients (Age: 77 ± 9years, 22% female) with symptomatic moderate to severe MR without atrial fibrillation. All patients underwent MitraClip following heart team decision without periinterventional major complications. Baseline echocardiography showed impaired left ventricular function (Ejection fraction (EF): 32,6 ± 11.2%), moderate to severe MR , increased systolic right ventricle pressure (RVSP: 46.1 ± 10.5 mmHg) and elevation in estimated left ventricle enddiastolic pressure (E/E´ ratio: 15.6 ± 7.3) in the patient cohort. There was no relevant mitral stenosis after the procedure (MPG: 3.3 ± 0.5 mmHg), however the MPG increased significantly after the procedure (p = 0.05). The E/E´ ratio significantly increased at FU (15.6 ± 7.3, 24.1 ± 13.2, p = 0.05) as well. The left atrial (LA) volumes and LA-muscular mass (End-diastolic volume [LA-EDV] and end-systolic volume [LA-ESV]) significantly increased at FU (LA-EDV: 83.1 ± 39.5ml, 115.1 ± 55.3ml, p = 0.012; LA-ESV: 58.4 ± 33.4ml, 80.1 ± 43.9ml, p = 0.031; 105.1 ± 49.3gr, 145.4 ± 70.6gr, p = 0.013). LA stroke volume significantly increased after the procedure (24.6 ± 12.5ml, 34.9 ± 19.1ml, p = 0.016). LA-EF and atrial global longitudinal strain (LA-GLS) showed no significant changes at FU (LA-EF: 31.7 ± 12.8%, 31.1 ± 12.3%, p= 0.8; LA-GLS: -10.8 ± 5.4%, -9.7 ± 4.45%, p = 0.4). Despite no relevant changes during FU, baseline E/E´ ratio (AUC: 0.652) and baseline aGLS (AUC: 0.694) were found to be independent predictors for mortality. Conclusion Transcatheter MV repair (TMVR) with the MitraClip procedure improves atrial stroke volume, increases atrial volumes and muscular mass acutely after the procedure. It might be explained by the acutely increased MPG and LVEDP after the MitraClip procedure. Baseline aGLS and E/E´ ratio were found to be independent predictors for mortality.

Global longitudinal strain and outcome after endoscopic mitral valve repair

“… 32 It must be noted, however, that the short follow‐up and low number of endpoints ( n = 7) were major limitations of the same study. 32 In our study, which involved a longer follow‐up period and a higher number of endpoints ( n = 64), LASr emerged as an independent predictor of all‐cause mortality and LA reverse remodelling. In contrast, and similar to the findings of the Özturk study, LAVI was not associated with mortality.…”

“…demonstrated three‐dimensional LASr, unlike LAVI, to be independently associated with mortality based on a 12‐month follow‐up following MitraClip implantation 32 . It must be noted, however, that the short follow‐up and low number of endpoints ( n = 7) were major limitations of the same study 32 . In our study, which involved a longer follow‐up period and a higher number of endpoints ( n = 64), LASr emerged as an independent predictor of all‐cause mortality and LA reverse remodelling.…”

“…Özturk et al . demonstrated three‐dimensional LASr, unlike LAVI, to be independently associated with mortality based on a 12‐month follow‐up following MitraClip implantation 32 . It must be noted, however, that the short follow‐up and low number of endpoints ( n = 7) were major limitations of the same study 32 .…”