Cajun Artificial Heart Laboratory, Mechanical Engineering Department, University of Louisiana at Lafayette, 241 E. Lewis St. RM320, Lafayette, LA 70503, United States.
Cajun Artificial Heart Laboratory, Mechanical Engineering Department, University of Louisiana at Lafayette, 241 E. Lewis St. RM320, Lafayette, LA 70503, United States.
Comput Methods Programs Biomed. 2018 Jul;161:93-102. doi: 10.1016/j.cmpb.2018.04.007. Epub 2018 Apr 18.
Patient-specific modeling (PSM) is gaining more attention from researchers due to its ability to potentially improve diagnostic capabilities, guide the design of intervention procedures, and optimize clinical management by predicting the outcome of a particular treatment and/or surgical intervention. Due to the hemodynamic diversity of specific patients, an adaptive pulmonary simulator (PS) would be essential for analyzing the possible impact of external factors on the safety, performance, and reliability of a cardiac assist device within a mock circulatory system (MCS). In order to accurately and precisely replicate the conditions within the pulmonary system, a PS should not only account for the ability of the pulmonary system to supply blood flow at specific pressures, but similarly consider systemic outflow dynamics. This would provide an accurate pressure and flow rate return supply back into the left ventricular section of the MCS (i.e. the initial conditions of the left heart).
Employing an embedded Windkessel model, a control system model was developed utilizing MathWorks' Simulink® Simscape™. Following a verification and validation (V&V) analysis approach, a PI-controlled closed-loop hydraulic system was developed using Simscape™. This physical system modeling tool was used to (1) develop and control the in silico system during verification studies and (2) simulate pulmonary performance for validation of this control architecture.
The pulmonary Windkessel model developed is capable of generating the left atrial pressure (LAP) waveform from given pulmonary factors, aortic conditions, and systemic variables. Verification of the adaptive PS's performance and validation of this control architecture support this modeling methodology as an effective means of reproducing pulmonary pressure waveforms and systemic outflow conditions, unique to a particular patient. Adult and geriatric with and without Heart Failure and a Normal Ejection Fraction (HFNEF) are presented.
The adaptability of this modelling approach allows for the simulation of pulmonary conditions without the limitations of a dedicated hardware platform for use in in vitro investigations.
由于患者特定建模（PSM）有可能提高诊断能力、指导干预程序设计以及通过预测特定治疗和/或手术干预的结果来优化临床管理，因此它越来越受到研究人员的关注。由于特定患者的血液动力学具有多样性，因此自适应肺模拟器（PS）对于分析外部因素对心脏辅助设备在模拟循环系统（MCS）中的安全性、性能和可靠性的可能影响至关重要。为了准确和精确地复制肺系统内的条件，PS 不仅应考虑肺系统在特定压力下供应血流的能力，还应同样考虑全身流出动力学。这将为返回供应到 MCS 的左心室部分（即左心的初始条件）提供准确的压力和流量。
采用嵌入式 Windkessel 模型，使用 MathWorks 的 Simulink®Simscape™开发了控制系统模型。采用验证和验证（V&V）分析方法，使用 Simscape™开发了 PI 控制闭环液压系统。该物理系统建模工具用于（1）在验证研究期间开发和控制虚拟系统，以及（2）模拟肺性能以验证该控制架构。
所开发的肺 Windkessel 模型能够从给定的肺因素、主动脉条件和系统变量生成左心房压力（LAP）波形。自适应 PS 性能的验证和该控制架构的验证支持这种建模方法是复制特定患者特有的肺压力波形和全身流出条件的有效手段。呈现了成人和老年人，有和没有心力衰竭以及射血分数正常（HFNEF）。
这种建模方法的适应性允许在没有用于体外研究的专用硬件平台限制的情况下模拟肺条件。
