Personalised thermal-fluid models for planning catheter ablation therapy for atrial arrhythmia

近年来，临床影像学的重大进展为人体内部功能和解剖学提供了丰富的详细信息。利用这些信息可以解决有关疾病进展及其治疗的基本问题。利用这一潜力的一个非常有前途的途径是基于这些最先进的数据创建器官的生物物理计算机模型。这些模型将可用的临床信息结合在一个一致的数学框架中，可以根据个体患者的具体特征进行定制。它们可以用来预测一个工作器官的复杂内部动态，以及它的疾病机制，为个性化治疗提供了一个强大的工具。这个项目将创建一个工具箱来生成心脏流动和温度的个性化模型。具体来说，这个平台将被设计用来模拟心房颤动，这是一种通常影响心脏一个腔室（左心房）的疾病，它的治疗方法被称为导管消融。当左心房颤动时，心室壁停止收缩并开始颤动。这种行为是由一个特定部位的异常电脉冲触发的，这个部位被称为驱动部位。结果，心房的血流被削弱了。这种不正常的行为会减少身体的血液供应。导管消融是通过导管加热烧灼心房壁的驱动部位，以抑制异常的电脉冲，恢复收缩。然而，患者的预后并不理想，单次手术后纤维性颤动的复发率很高。这是由于这种治疗效果强烈依赖于患者特异性因素，而这些因素很难单独从影像学数据中量化。拟议中的研究将侧重于使用个性化计算机模型改善结果。先前的试点工作已经证明了这种方法在预测消融引起的病变大小方面的潜力。该项目的总体目标是创建生理上准确的个性化模型，以告知消融参数的选择，如导管电压和消融时间。然后，该建模工具箱将应用于一组患者，目的是显著提高该方法的临床影响。这项研究将在圣托马斯医院进行，这是英国最大的心房颤动转诊中心之一。鉴于该项目的多学科方面，已经与不同专业领域的小组建立了内部合作。临床指导和患者数据集将由M. O. neill博士及其团队——心律失常研究小组提供，O. Aslanidi博士和D. Nordsletten博士将分别提供疤痕和血流模型方面的专业知识。因此，这项工作将在不同的领域产生影响，从临床研究到数学建模。然而，最终项目的受益者是患者自己，他们将从个性化和更有效的导管消融方法中受益。

In recent years, significant advances in clinical imaging have provided a wealth of detailed information on the internal function and anatomy of the human body. Fundamental questions on the progression of diseases and on their treatment can be addressed using this information. A highly promising avenue for the exploitation of this potential is the creation of biophysical computer models of the organs based on these state-of-the-art data. These models combine the available clinical information in a consistent mathematical framework that can be tailored to the specific characteristics of the individual patient. They can be used to predict the complex internal dynamics of a working organ, as well as its diseases' mechanisms, providing a powerful tool to personalise treatment. This project will create a toolbox to generate personalised models of flow and temperature in the heart. Specifically, this platform will be designed to simulate atrial fibrillation, a disease that commonly affects one chamber of the heart (the left atrium), and its treatment, known as catheter ablation. When the left atrium is in fibrillation, the wall stops contracting and starts quivering. This behavior is triggered by abnormal electrical impulses at a specific site, called the driver site. As a result, the motion of the blood flow in the atrium is weakened. This abnormal behavior can reduce the supply of blood to the body. Catheter ablation consists in burning the driver site in the atrial wall by applying heat via a catheter, in order to suppress the abnormal electrical impulses and restore contraction. However, patient outcomes are suboptimal and reoccurrence of fibrillation after a single procedure is high. This is due to the strong dependence of this treatment effectiveness on patient-specific factors that are difficult to quantify from the imaging data alone.The proposed research will focus on improving outcomes using personalised computer models. Previous pilot work has proven the potential of this type of approach in predicting the size of the lesion caused by ablation. The overall goal of this project is to create physiologically accurate, personalised models to inform the choice of the ablation parameters such as the catheter voltage and the ablation time. This modelling toolbox will then be applied to a cohort of patients with the aim of increasing significantly the clinical impact of the approach. The research will be undertaken at St Thomas' Hospital, one of the biggest UK referral centres for atrial fibrillation. Given the multi-disciplinary aspect of the project, internal collaborations have been set up with groups within different areas of expertise. Clinical guidance and patient datasets will be provided by Dr M. O'Neill and his team, the Cardiac Arrhythmia Research Group, while Dr O. Aslanidi and Dr D. Nordsletten will provide expertise in scar and blood flow modelling, respectively. This work will therefore generate impact in different areas, from clinical research to mathematical modelling. Ultimately, however, the beneficiaries of the proposed project are the patients themselves, who will benefit from a personalised and more efficient approach to catheter ablation.