Spectral method of photoplethysmogram processing for screening of atherosclerosis

The paper is devoted to the analysis of the existing indicators for the diagnostic of arterial vessels condition and the development of new ones based on the contour analysis of the pulse wave. The performed analysis of the techniques used to process the pulse wave signal has shown that the classical approach to the morphological analysis of pulse wave in terms of stiffness index and reflection index does not provide sufficient diagnostic accuracy due to the instable detection of the reflected wave maximum. A new technique of contour analysis based on spectral transformation of a sequence of replicated single fragments of the pulse wave is developed. The comparative analysis of the contour analysis methods has shown that the proposed method detects the changes of the pulse wave caused by diseases in the form of increased difference between the indicator values.