Goal: Create a semi-automated, graphical, stand-alone application that uses clinically available asynchronous pressure and Doppler velocity captures to rapidly calculate, display, and interpret the pulmonary vascular impedance (PVZ) spectra. Methods: MATLAB-based software was written to analyze PVZ by creating a composite PVZ (cPVZ) spectra comprised of asynchronous screen captures of pulmonary arterial pressure and pulmonary arterial pulsed-wave Doppler velocity waveforms obtained during standard of care procedures. The pressure waveform, Doppler frequency envelopes, and ECG signals were re-digitized via automated border detection. cPVZ of averaged representative beats was calculated in the frequency domain via Fast Fourier Transform, and plotted vs harmonic z. Results: Successful generation of impedance spectra (PVZ(z)), where z is the harmonic, and additional parameters for characteristic impedance (Zc) and stiffness (Zs) were calculated as the mean of PVZ(2-4), and the sum of PVZ (1, 2), respectively. Conclusions: A graphically driven analysis of PVZ, calculated from standard of care right heart catheterization and echocardiography is possible. This system can help characterize both the steady and pulsatile components of right ventricular (RV) afterload in the clinical setting.

中文翻译：

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用于在临床环境中计算肺血管阻抗的半自动图形系统

目标：创建一个半自动化、图形化、独立的应用程序，该应用程序使用临床可用的异步压力和多普勒速度捕获来快速计算、显示和解释肺血管阻抗 (PVZ) 频谱。方法：编写了基于 MATLAB 的软件，通过创建复合 PVZ (cPVZ) 光谱来分析 PVZ，该光谱由在标准护理程序期间获得的肺动脉压力和肺动脉脉冲波多普勒速度波形的异步屏幕捕获组成。压力波形、多普勒频率包络和 ECG 信号通过自动边界检测重新数字化。通过快速傅里叶变换在频域中计算平均代表性节拍的 cPVZ，并绘制与谐波 z 的关系图。结果：成功生成阻抗谱 (PVZ(z))，其中 z 是谐波，特性阻抗 (Zc) 和刚度 (Zs) 的附加参数计算为 PVZ(2-4) 的平均值，以及 PVZ 的总和(1, 2)，分别。结论：从护理标准右心导管插入术和超声心动图计算得出的 PVZ 图形驱动分析是可能的。该系统可以帮助表征临床环境中右心室 (RV) 后负荷的稳定和搏动分量。