Variations in non-invasive radial artery pulse waveform at different measuring positions

Noninvasive radial artery pulse wave has been widely not only for the pulse wave analysis (PWA) itself but also for assessment of arterial stiffness with estimated aortic pulse wave from peripheral pulse wave. In this study, we tested the differences between the extracted parameters, including AIx, from radial artery pulse waves measured at three different positions preliminarily. A 30 years old female involved in this experiment and this subject has no evidence about cardiovascular diseases. Radial pulse waves were recorded at three different positions on left lower arm ten times for each position. These positions are widely used in pulse diagnosis of traditional medicine. As results of repeated measures ANOVA analysis, 9 parameters were found which had significantly differences in between measuring positions (P>0.05). These parameters were P-AIx, PP-Amp, A-T1, A-Tr, AIx, AIx-@HR75, ESP, MP-Sys and MP-Dia. And, by Spearman correlation test at P2, it was observed that P-AIx (r =0.894), PP Amp (r=-0.765), AIx-@HR75 (r=0.929), ESP (r=0.893) and MP-Dia (r=0.792) were highly correlated with AIx. Elaborately, the correlation coefficients between each parameter were high in similar degrees (r<0.70). Further studies on what make differences in these parameters between measuring positions are need. And, ultimately, we need to determine the best measuring process, including measuring position, hold-down pressure, signal quality validation and so on, so to achieve the optimal waveform which represents subject's health condition for both western medicine and traditional medicine.