Erica Manzan1,2, Danila Azzolina3, Dario Gregori3, Eleonora Bizzotto4, Andrea Colli5, Gino Gerosa1. 1. Cardiac Surgery Unit, Department of Cardiac-Thoracic-Vascular Sciences and Public Health, University of Padua, Padua, Italy. 2. Cardiac Surgery Unit, A.O.R. San Carlo Hospital, Potenza, Italy. 3. Unit of Biostatistics, Epidemiology and Public Health, Department of Cardiac-Thoracic-Vascular Sciences and Public Health, University of Padua, Padua, Italy. 4. Cardiology Unit, Policlinico di Abano Terme, Abano Terme, Italy. 5. Cardiac Surgery Unit, Department of Surgical, Medical and Molecular Pathology and Critical Care, University of Pisa, Pisa, Italy.
Abstract
BACKGROUND: Trans-apical, echo-guided NeoChord mitral valve (MV) repair is an innovative procedure to treat degenerative mitral regurgitation (MR) without concomitant annuloplasty. Recently, leaflet-to-annulus index (LAI) has been identified as a positive prognostic predictor of outcomes at 1-year follow up. The aim of this study is to develop a pre-operative predictor tool to assess probability of success with NeoChord procedure utilizing multi-factor echocardiographic and anatomic variables. METHODS: We included ninety-one consecutive patients with prolapse/flail of the posterior mitral leaflet, who subsequently underwent NeoChord MV repair between November 2013 and October 2016. All patients completed post-operative echocardiographic follow-up assessments for up to 2 years. A random forest regression algorithm identified and ranked the most relevant predictors of moderate-severe MR. A multi-variable Cox regression model was performed at follow-up intervals, to assess variables associated with residual MR that was classified as mild or less. Bootstrapping re-samples were used to validate an estimated survival model. Predictive accuracy was assessed using a discrimination index that corrected for over-optimism. RESULTS: We developed a nomogram which used the results of a multi-variable model to predict the probability of mild or less residual MR at follow-up periods (discharge, 1, 3, 6 months, 1 and 2 years). Identified predictors included LAI, systolic pulmonary artery pressure, indexed left ventricle end-systolic volume (iLVESV), prolapse/flail width (FW), systolic antero-posterior (AP) annulus diameter, systolic latero-lateral (LL) annulus diameter and presence of calcification. CONCLUSIONS: A NeoChord MV repair prediction tool would be helpful in clinical decision-making and in the identification of patients who may benefit from a ringless mitral valve repair using the NeoChord procedure. 2021 Annals of Cardiothoracic Surgery. All rights reserved.
BACKGROUND: Trans-apical, echo-guided NeoChord mitral valve (MV) repair is an innovative procedure to treat degenerative mitral regurgitation (MR) without concomitant annuloplasty. Recently, leaflet-to-annulus index (LAI) has been identified as a positive prognostic predictor of outcomes at 1-year follow up. The aim of this study is to develop a pre-operative predictor tool to assess probability of success with NeoChord procedure utilizing multi-factor echocardiographic and anatomic variables. METHODS: We included ninety-one consecutive patients with prolapse/flail of the posterior mitral leaflet, who subsequently underwent NeoChord MV repair between November 2013 and October 2016. All patients completed post-operative echocardiographic follow-up assessments for up to 2 years. A random forest regression algorithm identified and ranked the most relevant predictors of moderate-severe MR. A multi-variable Cox regression model was performed at follow-up intervals, to assess variables associated with residual MR that was classified as mild or less. Bootstrapping re-samples were used to validate an estimated survival model. Predictive accuracy was assessed using a discrimination index that corrected for over-optimism. RESULTS: We developed a nomogram which used the results of a multi-variable model to predict the probability of mild or less residual MR at follow-up periods (discharge, 1, 3, 6 months, 1 and 2 years). Identified predictors included LAI, systolic pulmonary artery pressure, indexed left ventricle end-systolic volume (iLVESV), prolapse/flail width (FW), systolic antero-posterior (AP) annulus diameter, systolic latero-lateral (LL) annulus diameter and presence of calcification. CONCLUSIONS: A NeoChord MV repair prediction tool would be helpful in clinical decision-making and in the identification of patients who may benefit from a ringless mitral valve repair using the NeoChord procedure. 2021 Annals of Cardiothoracic Surgery. All rights reserved.