Minimaly invasive mitral valve repair with Neochord system in patients with degenerative mitral disease: echocardiographic assessment and predictors for mid-term outcome
Authors: Drasutiene A , Janusauskas V , Speziali G , Zakarkaite D , Budra M , Rucinskas K , Aidietis A 
Published: November 2020

Abstract

Introduction
Various minimally invasive mitral valve (MV) repair techniques are available to treat degenerative mitral regurgitation (MR). Transapical implantation of artificial chordae on a beating heart is performed using the NeoChord DS1000 device with real-time TEE guidance.

Purpose
1)To assess preoperative and the mid-term follow-up echocardiographic data in patients after MV repair using the NeoChord DS1000 device; 2)to investigate the changes of left ventricle (LV), left atrium (LA) and mitral annulus dimensions during the follow-up period; 3)to assess the difference of baseline echocardiographic parameters between successful and not-successful (severe residual MR) MV repair groups; 4)to identify the preoperative echocardiographic variables that may be associated with recurrence of MR at mid-term follow.

Methods
All patients after transapical MV repair with Neochord implantation in Vilnius University hospital were prospectively entered into the study. The acquired preoperative and follow-up echocardiographic datasets were analysed. According to the residual MR at follow-up, patients were stratified to 2 groups: group A – successful durable MV repair (residual MR ≤2); group B – MV repair failure (recurrence of severe MR or reintervention). Values were expressed as Mean±SD. Univariable regression analysis was used to identify anatomical predictors of residual MR.

Results
53 (70.67%) patients had a residual MR ≤2 (Group A) and 22 (29.33%) residual MR≥2+ (Group B) at 26±6 months follow-up. At baseline, Group B patients had significantly larger left ventricle end diastolic diameter (LVEDD) (mean difference 5.67±1.29mm, p&lt;0.0001) left ventricle end systolic diameter (LVESD) (mean difference 4.08±1.57mm, p=0.012), LA volume index (mean difference 21.57±5.003 p&lt;0.0001) and higher systolic pulmonary pressure values (mean difference 10.46±3.34, p&lt;0.003) compared with group A. Overall, a significant reduction in LA volume index (mean change 15.69±4.15ml/m2, p&lt;0.001), LA diameter (mean change 3.15±1.24, p=0.012), LV diameter (mean change in LVEDD 4.78±0.88mm p&lt;0.000) was observed at 24 months follow up. There was no significant changes in MV annular parameters at follow up. Left atrium volume (OR 1.018; 95% CI 1.006–1.035; p=0.009), left atrium volume index (OR 1.038; 95% CI 1.013–1.072; p=0.010), LVEDD (OR 1.201; 95% CI 1.088–1.353; p=0.0008), LVESD (OR 1.122; 95% CI 1.02–1.248); p=0.0236) and sPAP (OR 1.418; 95% CI 1.139–2.016; p=0.0014) were all significantly associated with the worse outcome (MR &gt;2) after mini-invasive MV repair in univariable regression analysis.

Conclusions
Minimaly invasive MV repair with Neochord system on beating heart is effective in patients with degenerative MR. Baseline echocardiographic characteristics predictive for a worse middle term outcome are mainly related to LV and LA remodeling. Reverse remodeling of LV and LA is observed during the follow-up period with no significant changes in MV annulus.

Funding Acknowledgement
Type of funding source: None