Bachman Timothy, Kim Kang, Simon Marc
Department of BioengineeringUniversity of Pittsburgh Pittsburgh PA 15261 USA.
Department of Bioengineering and Department of MedicineUniversity of Pittsburgh Pittsburgh PA 15261 USA.
IEEE Open J Eng Med Biol. 2021 May 6;2:198-200. doi: 10.1109/OJEMB.2021.3076726. eCollection 2021.
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. 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. 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. 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.
创建一个半自动的、图形化的独立应用程序，该程序使用临床上可用的异步压力和多普勒速度捕获数据，以快速计算、显示和解释肺血管阻抗（PVZ）频谱。编写了基于MATLAB的软件，通过创建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的复合PVZ（cPVZ）频谱来分析PVZ。通过自动边界检测对压力波形、多普勒频率包络和心电图信号进行重新数字化。通过快速傅里叶变换在频域中计算平均代表性搏动的cPVZ，并绘制相对于谐波z的曲线。成功生成阻抗频谱（PVZ(z)），其中z为谐波，并分别计算特征阻抗（Zc）和刚度（Zs）的其他参数，分别作为PVZ(2 - 4)的平均值和PVZ(1, 2)的总和。可以对由标准护理右心导管检查和超声心动图计算得出的PVZ进行图形驱动分析。该系统有助于在临床环境中表征右心室（RV）后负荷的稳定和搏动成分。
