4D ventricle-valve model risk stratification for planning surgical treatment of ischemic mitral regurgitation

项目摘要/摘要 缺血性二尖瓣返流(IMR)是一种二尖瓣正常结构功能障碍的疾病。 由于心肌梗死(MI)后左室(LV)重构。IMR影响着近300万美国人 随着人口老龄化，这个问题的严重程度预计还会增加。IMR有相当高的死亡率 甚至与轻度MR严重程度相关的比率。二尖瓣环状成形术 IMR的首选治疗策略；然而，中或重度IMR在12个月内复发 手术是很常见的。心胸外科试验网络(CTSN)多项最新备受瞩目的结果- 关于IMR的TICENTER随机试验已经证实早期复发IMR的发生率很高。更重要的是， 这些研究强调了复发的IMR对左室重构和临床结果的不利影响。这个 CTSN试验表明，在12个月和24个月时，左室容量缩小或存活时间没有显著差异 然而，亚组分析表明，修复患者 发生复发的IMR患者的左心室体积没有减少，而修复后的患者没有复发 LV缩容效果优于瓣膜置换术。CTSN IMR试验结果 表明对可可靠预测MV修复失败的术前风险分层工具的需求未得到满足。这样的一个 该工具将通过仅在可能发生以下情况的患者中进行瓣膜修复来显著减少复发的IMR问题 在复发风险较高的患者中体验持久的结果并进行瓣膜置换术。《长河》 学期目标是通过改善术前风险分层来提高IMR手术治疗的质量 图像分析工具。这项建议的总体目标是提高IMR复发的预测能力。 平移该模型以包括左心室(LV)。理由是，虽然IMR表现为MV Malcoapta- 因此，本病的根本原因是左室重构。中心假设是从图像中提取的特征 综合左心室和二尖瓣(LVMV)模型将比目前更准确地预测复发 仅限MV的型号。为了实现这一目标，并通过追求以下具体目标来检验中心假设：1) 建立4D集成的LVMV模型，并与术中3DTE比较该模型的拟合精度 图像恢复到现有纯MV模型的图像。2)评估来自整合的生物标记物的能力 LVMV模型预测IMR复发，并与单纯MV模型的预测值进行比较。该项目 意义重大，因为如果成功，集成的LVMV模型将被纳入戈尔曼实验室 努力将这项技术转化到手术室，从而提高存活率，减少迫在眉睫的 临床负担和重复手术次数。

Project Summary/Abstract Ischemic mitral regurgitation (IMR) is a disease where the normal mitral valve (MV) structure is dysfunctional due to left ventricular (LV) remodeling after a myocardial infarction (MI). IMR affects nearly 3 million Americans and the magnitude of this problem is expected to grow as the population ages. IMR has a substantial mortality rate that is associated with even mild MR severity. Mitral valve repair with undersized ring annuloplasty has been the preferred treatment strategy for IMR; however, the recurrence of moderate or severe IMR within 12 months of surgery is common. Recent high profile results from the Cardiothoracic Surgical Trials Network (CTSN) mul- ticenter randomized trials on IMR have confirmed a high incidence of early recurrent IMR. More importantly, these studies highlighted the adverse impact of recurrent IMR on LV remodeling and clinical outcomes. The CTSN trials demonstrated no significant difference in LV volume reduction or survival at 12 and 24 months between repair and replacement groups; however, subgroup analysis demonstrated that repair patients that developed recurrent IMR had no reduction in LV volume while repair patients without recurrence experienced LV volume reduction that was superior to patients having valve replacement. The results of the CTSN IMR trials indicate an unmet need for a pre-operative risk stratification tool that reliably predicts MV repair failure. Such a tool would significantly reduce the problem of recurrent IMR by performing valve repair only in patients likely to experience a durable result and performing valve replacement in patients with high risk of recurrence. The long term goal is to improve quality of surgical therapy in IMR by improving risk-stratification pre-operatively using image analysis tools. The overall objective of this proposal is to improve the prediction IMR recurrence by ex- panding this model to include the left ventricle (LV). The rationale is that while IMR manifests as MV malcoapta- tion, the root cause of the disease is LV remodeling. The central hypothesis is that features extracted from the integrated left ventricular and mitral valve (LVMV) model will predict recurrence more accurately than the current MV-only model. To fulfill this objective and test the central hypothesis by pursuing the following specific aims: 1) Develop the 4D integrated LVMV model and compare the accuracy of fitting this model to intraoperative 3DTE images to that of the existing MV-only model. 2) Assess the ability of biomarkers derived from the integrated LVMV model to predict IMR recurrence, and compare to the predictive value of the MV-only model. The project is significant because, if successful, the integrated LVMV model will be incorporated into the Gorman lab ongoing effort translating this technology to the operating room, thus improving survival rates, reducing the impending clinical burden and the number of repeated procedures.