Nonlinear Dynamics Research Center, Kyungpook National University, Daegu, Republic of Korea.
Bio-Medical Research Institute, Kyungpook National University & Hospital, Daegu, Korea.
Cardiovasc Eng Technol. 2023 Feb;14(1):104-114. doi: 10.1007/s13239-022-00638-y. Epub 2022 Jul 25.
This study establishes a reliable image-based multivariable technique for measuring the trans-stenotic pressure gradient.
A self-made in vitro steady flow model based on adjustable velocities and stenotic properties were used as the experimental subject. The pre-stenotic flow velocity, severity, and length of the stenosis were used as the input variables. Based on equations used to fit the plots of the physically measured pressure gradient values versus each input variable, a multivariable formula for the pressure gradient measurement could then be derived. The flow model was scanned using velocity-encoded phase-contrast magnetic resonance imaging (PC-MRI) to validate the derived formula while simultaneously measuring the trans-stenotic pressure gradient. The correlation between the physically-measured pressure gradient values and the pressure gradient values calculated using the new formula were subsequently analyzed.
The results of linear regression analysis using the physically measured pressure gradient values for the new method were compared to values obtained using the simplified Bernoulli equation (R, 0.991, and 0.975, respectively). In a paired t-test, no statistically significant difference was found between the new method and the physical measurements.
The derived multivariable technique was found to reliably measure the trans-stenotic pressure gradient, with better performance than a traditional procedure based on the simplified Bernoulli equation.
本研究建立了一种可靠的基于图像的多变量技术，用于测量跨狭窄处的压力梯度。
使用基于可调速度和狭窄特性的自制体外稳态流模型作为实验对象。将狭窄前的血流速度、狭窄程度和狭窄长度作为输入变量。基于拟合物理测量压力梯度值与每个输入变量的图的方程，可以推导出压力梯度测量的多变量公式。使用流速编码相位对比磁共振成像（PC-MRI）对血流模型进行扫描，以验证推导的公式，同时测量跨狭窄处的压力梯度。随后分析物理测量压力梯度值与使用新公式计算的压力梯度值之间的相关性。
使用新方法的物理测量压力梯度值进行线性回归分析的结果与简化伯努利方程（R，0.991 和 0.975）的结果进行比较。在配对 t 检验中，新方法与物理测量之间没有发现统计学上的显著差异。
所推导的多变量技术被发现能够可靠地测量跨狭窄处的压力梯度，其性能优于基于简化伯努利方程的传统方法。
