Non-invasive monitoring and evaluating cardiac function of pregnant women based on a relative value method

Abstract

This paper proposed a relative value method for measuring the indicators of cardiac reserve and investigated the application on monitoring and evaluating cardiac function for pregnant women. A heart sound sensor is placed at the precordial region to detect phonocardiogram. In order to access the cardiac reserve mobilization level during pregnancy, the cardiac reserve indicators of 1,683 normal pregnant women, 96 abnormal cases with different obstetric complications and 624 non-pregnant women were measured, analyzed and compared. The result shows that the differences between the indicators of pregnant and non-pregnant women were significant (p < 0.05). The ratio of diastolic to systolic duration (D/S) was obviously declined with the increase of gestational weeks and the occurrence of obstetric complication. This very encouraging result indicates that the D/S can be used as an indicator for evaluating the cardiac safety of parturition, which provides a reference for cardiac safety assessment of pregnant women.

A non-invasive approach to investigation of ventricular blood pressure using cardiac sound features

“…This approach performed satisfactorily for diagnosis of hypertensive subjects (Wong et al 2006b). The ratio of systolic time interval to diastolic time interval was also taken as an important time-domain feature and it was used as an indicator of cardiac reserve (Xiao et al 2003, Guo et al 2012.…”

A recognition method research based on the heart sound texture map

“…Methods of time-frequency analysis of non-stationary signal mainly include the Short-time Fourier Transform and wavelet transform, wavelet packet transform and S transform, 10 the timefrequency images getting from the Heart Sound signal frequency changing, is called Heart Sound time-frequency diagrams, the Heart Sound Texture Map can be got by reducing part of some redundant information in Heart Sound time-frequency diagram. According to the characteristics of Heart Sound, in this paper, we give the structure principles of Heart Sound Window Function and the realization method of Heart Sound by focusing on a kind of Heart Sound Window Function, discusses the window length by experiments.…”

A new method of heart sound signal analysis based on independent function element

“…The research on the denoising, feature extraction and classification methods of heart sound signals, is very positive in the smart heart sound auscultation and identification by heart sound. [9][10][11] A cycle of heart sound signals can be described as: Among them, s 1 , s 2 is the first and second heart sound signals, The third and fourth heart sounds s 3 , s 4 is weak, s 5 is heart sounds noise, c t is composite coefficient. Heart sound has the following characteristics:…”

“…[1][2][3][4][5][6][7][8] They have their advantages, but also some disadvantages. [7][8][9] The paper studies a new method for heart sound signal processing in statistical domain. In view, the component composition obtained from conventional linear transformation may be irrelevant, but usually does not meet the characteristics of statistical independence.…”