3D MRI-Based Modeling for Computer-Aided Right Ventricle Remodeling Surgery

描述（由申请人提供）：先天性心脏手术后晚期发生的右心室功能障碍是成人先天性心脏病患者心力衰竭的最常见原因之一。在法洛四联学（ToF）中，最常见的青紫型心脏缺陷，婴儿期的初始修复涉及在右心室流出处（包括肺动脉瓣）切开和补片，这通常导致慢性肺反流和右心室瘢痕/补片扩张导致严重右心室扩张和功能障碍的晚期发展。目前晚期右室功能障碍的手术治疗，包括肺动脉瓣插入和右室流出补片缩小，减少了右室体积，但并没有导致可预测的右室功能改善。一项由NHLBI赞助的随机前瞻性试验正在评估一种更激进的手术，包括广泛去除疤痕和流出贴片。然而，目前还没有可用的方法来预测手术后的结果，或者对于给定的pt，什么是最佳的手术，也就是说，没有临床上有用的工具来确定患者特异性治疗。在这个项目中，我们建议开发一种计算建模方法，以确定各种重建方案治疗ToF患者失效RV的有效性和适用性。我们将使用无创心脏磁共振成像（CMR）提供患者特异性左室/左室形态学、变形和血流数据，用于构建和验证计算模型。构建基于三维cmr的RV/LV组合模型，包括流固耦合（RV/LV和RV贴片）、两层RV/LV结构、各向异性材料特性、纤维取向、主动收缩等，模拟血流、心脏运动、应力/应变分布，评估不同重构方式对RV功能的影响，寻求最佳的RV容积和贴片设计，改善术后RV功能。正在进行的nhlbi资助的临床试验的临床成像和血流动力学数据将用于建立和验证该模型。我们的最终目标是将该方法应用于患者特异性的计算机辅助心脏手术计划，以达到先天性心脏缺陷右心室功能障碍患者的最佳手术程序设计和结果。一个由先天性心脏外科、心脏病学和计算数学领域经验丰富的研究人员组成的多学科小组将进行这个项目。公共卫生相关性：该项目旨在使用从正在评估手术的法洛四联症修复患者获得的MRI图像来开发右心室功能的计算模型。最终目标是建立预测手术后结果和优化右心室功能的模型。用于本研究的核磁共振成像是临床指示性研究，作为这些患者护理的一部分，目前是在Tal Geva博士担任首席研究员的批准协议下获得的。

DESCRIPTION (provided by applicant): Right ventricular dysfunction developing late after congenital cardiac surgery is one of the most common causes of heart failure in adults with congenital heart disease. In tetra logy of Fallot (ToF), the most common cyanotic heart defect, initial repair in infancy involves an incision and patch in the RV outflow, including the pulmonary valve, which often results in late development of severe RV dilatation and dysfunction due to chronic pulmonary regurgitation and RV scarring/patch dilatation. Current surgical management of late RV dysfunction, consisting of pulmonary valve insertion and reduction of the RV outflow patch, reduces RV volume but does not result in a predictable improvement in RV function. A more radical procedure, which includes extensive removal of scar and outflow patch, is being evaluated in an NHLBI sponsored randomized prospective trial. However, there is no currently available method for predicting outcome after either procedure or what the optimal procedure is for a given pt., i.e. no clinically useful tools for determining patient-specific therapy. In this project, we propose to develop a computational modeling approach to determine the efficacy and suitability of the various reconstructive options to treat failing RV in ToF pts. We will use non-invasive cardiac magnetic resonance imaging (CMR) to provide patient-specific RV/LV morphology, deformation, and flow data for the construction and validation of computational models. 3D CMR-based RV/LV combination models will be constructed, which include fluid-structure interactions (RV/LV and RV patch), two-layer RV/LV structure, anisotropic material properties, fiber orientation, and active contraction to simulate blood flow, heart motion, and stress/strain distribution to evaluate the effect of different remodeling procedures on RV function, and to seek an optimal RV volume and patch design to improve post-operative RV function. Clinical imaging and hemodynamic data from an ongoing NHLBI-funded clinical trial will be used to build and validate the model. Our ultimate goal is to apply this methodology in patient- specific computer-aided cardiac surgery planning to reach optimal surgical procedure design and outcome in patients with RV dysfunction from congenital heart defects. A multidisciplinary group of experienced investigators in congenital cardiac surgery, cardiology and computational mathematics will conduct this project. PUBLIC HEALTH RELEVANCE: This project aims to use MRI images obtained from patients with repair tetralogy of Fallot that are being evaluated for surgery to develop computational models of right ventricular function. The ultimate goal is to develop models that will predict outcomes and optimize right ventricular function after surgery. The MRI's to be used for this study are clinically indicated studies as part of the care of these patients and are currently obtained under an approved protocol where Dr. Tal Geva is the principal investigator.