Background

In object-oriented or acausal modelling, components of the model can be connected topologically, following the inherent structure of the physical system, and system equations can be formulated automatically. This technique allows individuals without a mathematics background to develop knowledge-based models and facilitates collaboration in multidisciplinary fields like biomedical engineering. This study conducts a preclinical evaluation of a ventricular assist device (VAD) in assisting advanced-stage heart failure patients in an acausal modelling environment.

Methods

A comprehensive object-oriented model of the cardiovascular system with a VAD is developed in MATLAB/SIMSCAPE, and its hemodynamic behaviour is studied. An analytically derived pump model is calibrated for the experimental prototype of the Istanbul Heart VAD. Hemodynamics are produced under healthy, diseased, and assisted conditions. The study features a comprehensive collection of advanced-stage heart failure patients’ data from the literature to identify parameters for disease modelling and to validate the resulting hemodynamics.

Results

Regurgitation, suction, and optimal speeds are identified, and trends in different hemodynamic parameters are observed for the simulated pathophysiological conditions. Using pertinent parameters in disease modelling allows for more accurate results compared to the traditional approach of arbitrary reduction in left ventricular contractility to model dilated cardiomyopathy.

Conclusion

The current research provides a comprehensive and validated framework for the preclinical evaluation of cardiac assist devices. Due to its object-oriented nature, the featured model is readily modifiable for other cardiovascular diseases for studying the effect of pump operating conditions on hemodynamics and vice versa in silico and hybrid mock circulatory loops. The work also provides a potential teaching tool for understanding the pathophysiology of heart failure, diagnosis rationale, and degree of assist requirements.

中文翻译：

---

晚期心力衰竭的非因果模型和伊斯坦布尔心脏心室辅助装置对患者数据的支持

背景

在面向对象或非因果建模中，模型的组件可以按照物理系统的固有结构进行拓扑连接，并且可以自动制定系统方程。这项技术允许没有数学背景的个人开发基于知识的模型，并促进生物医学工程等多学科领域的协作。本研究对心室辅助装置 (VAD) 在非因果建模环境中协助晚期心力衰竭患者进行临床前评估。

方法

在 MATLAB/SIMSCAPE 中开发了带有 VAD 的心血管系统综合面向对象模型，并研究了其血流动力学行为。分析得出的泵模型针对 Istanbul Heart VAD 的实验原型进行了校准。血流动力学是在健康、患病和辅助条件下产生的。该研究全面收集了文献中的晚期心力衰竭患者数据，以确定疾病模型的参数并验证由此产生的血流动力学。

结果

确定反流、抽吸和最佳速度，并观察模拟病理生理条件下不同血液动力学参数的趋势。与任意降低左心室收缩力来模拟扩张型心肌病的传统方法相比，在疾病建模中使用相关参数可以得到更准确的结果。

结论

目前的研究为心脏辅助装置的临床前评估提供了一个全面且经过验证的框架。由于其面向对象的性质，该特征模型很容易针对其他心血管疾病进行修改，以研究泵运行条件对血流动力学的影响，反之亦然。这项工作还为理解心力衰竭的病理生理学、诊断原理和辅助要求程度提供了潜在的教学工具。