采样频率与数据长度对中心动脉波形重建的影响

Effects of Sampling Frequency and Data Length on the Central Aortic Waveform Reconstruction

传递函数法重建CAP (central aortic pressure)多是基于自回归各态历经(auto regressive e Xogenous,ARX)模型或傅里叶变换,未考虑采样频率、数据长度.为了研究采样频率和数据长度对重建CAP的影响,基于ARX模型和傅里叶变换,重建CAP并分析误差.结果表明,采样频率100 Hz,数据长度大于3 s时,基于ARX模型重建CAP效果较好(均方根误差(306. 6±80. 0) Pa,波形匹配度89%);基于傅里叶变换的算法对采样频率不敏感,数据长度为6 s时效果较好(均方根误差(493. 3±320. 0) Pa,波形匹配度84%).

Non-invasive CAP(central aortic pressure)reconstruction is mostly based on the auto regressive eXogenous(ARX)model or Fourier transform in transfer function method,without considering the factors such as sampling frequency and data length.Based on the ARX model and the Fourier transform,the error of reconstruction CAP was analyzed for studing the effects of sampling frequency and data length on the CAP.The results show that when sampling frequency is 100 Hz and data length is greater than 3 s,CAP can be better reconstructed by ARX model(RMSE:(306.6±80.0)Pa;FIT: 89 %).The algorithm based on the Fourier transform is insensitive to sampling frequency.When data length is set to 6 s,the reconstructed CAP has a better performance(RMSE:(493.3±320.0)Pa,FIT:84 %).