Manzan Erica, Azzolina Danila, Gregori Dario, Bizzotto Eleonora, Colli Andrea, Gerosa Gino
Cardiac Surgery Unit, Department of Cardiac-Thoracic-Vascular Sciences and Public Health, University of Padua, Padua, Italy.
Cardiac Surgery Unit, A.O.R. San Carlo Hospital, Potenza, Italy.
Ann Cardiothorac Surg. 2021 Jan;10(1):122-130. doi: 10.21037/acs-2020-mv-96.
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.
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.
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.
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.
经心尖、超声引导下的NeoChord二尖瓣（MV）修复术是一种治疗退行性二尖瓣反流（MR）且无需同期进行瓣环成形术的创新手术。最近，瓣叶-瓣环指数（LAI）已被确定为1年随访结果的阳性预后预测指标。本研究的目的是开发一种术前预测工具，利用多因素超声心动图和解剖学变量评估NeoChord手术成功的概率。
我们纳入了91例连续的二尖瓣后叶脱垂/连枷样病变患者，这些患者于2013年11月至2016年10月期间接受了NeoChord二尖瓣修复术。所有患者均完成了长达2年的术后超声心动图随访评估。随机森林回归算法识别并对中重度MR的最相关预测指标进行了排序。在随访期间进行多变量Cox回归模型，以评估与轻度或更低程度残余MR相关的变量。使用自举重采样来验证估计的生存模型。使用校正过度乐观的鉴别指数评估预测准确性。
我们开发了一种列线图，该列线图使用多变量模型的结果来预测随访期（出院时、1、3、6个月、1年和2年）轻度或更低程度残余MR的概率。确定的预测指标包括LAI、收缩期肺动脉压、左心室收缩末期容积指数（iLVESV）、脱垂/连枷宽度（FW）、收缩期前后径（AP）瓣环直径、收缩期左右径（LL）瓣环直径和钙化的存在。
NeoChord二尖瓣修复预测工具将有助于临床决策，并有助于识别可能从使用NeoChord手术的无环二尖瓣修复中获益的患者。
