System and method for estimating central arterial blood pressure from cuff oscillatory waveform features

Abstract

The application provides a system and method for estimating central arterial blood pressure by fusing cuff oscillatory waveform features, wherein the system comprises a signal acquisition module, an oscillatory wave amplification module, an oscillatory wave waveform feature analysis module, a pressure wave transit time calculation module, a central arterial blood pressure calculation module and a report output module. The system and method for estimating central arterial blood pressure by fusing cuff oscillatory waveform features can improve the individualized estimation accuracy of central arterial blood pressure by analyzing the waveform features of the cuff oscillatory wave and fusing the waveform features into the estimation of the pressure wave transit time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of central arterial blood pressure measurement, and particularly relates to a system and method for estimating central arterial blood pressure by fusing cuff oscillatory waveform features. BACKGROUND

[0002] Central arterial blood pressure (i.e. the blood pressure in the human aorta) is significantly different from peripheral arterial blood pressure (such as brachial, radial arterial pressure), and the difference between the two is related to various cardiovascular factors. Clinical studies have shown that central arterial blood pressure has higher predictive value for organ damage and cardiovascular events than peripheral blood pressure, and plays an important role in evaluating the efficacy of antihypertensive drugs, so central arterial blood pressure measurement is of great significance in clinical practice.

[0003] The gold standard for measuring central arterial blood pressure in clinic is invasive pressure wire measurement, but this method has risks of infection and vascular injury, and is not suitable for routine health detection and screening of large populations. Therefore, non-invasive central arterial blood pressure estimation technology has become the mainstream of research. The pulse wave inversion method based on generalized transfer function (GTF) is one of the most widely used non-invasive central arterial blood pressure measurement techniques. This technique uses GTF to convert the pulse wave signal measured at the periphery of the body (such as the wrist or upper arm) to obtain the central arterial blood pressure wave, thereby achieving the estimation of central arterial systolic and diastolic pressure. SphygmoCor®Xcel from Australia is a representative device that uses this method. However, the application of GTF obtained from a specific population to all populations may cause large and randomly distributed errors in the estimation of central arterial blood pressure. A-PULSE CASPro from Singapore uses the n-point moving average (NPMA) method. This method uses a low-pass filter to smooth the non-invasive peripheral arterial blood pressure wave to eliminate the amplification effect of the pulse wave from the central artery to the peripheral artery, thereby achieving the estimation of central arterial systolic pressure, but this method cannot be personalized like GTF, so if the best denominator of the moving average is determined empirically using validation data from a selected population, the accuracy of this method cannot be better than that of the GTF-based method. At the same time, further theoretical and experimental studies have shown that there is no statistically significant difference in measurement accuracy between NPMA and GTF methods. Some scholars have also proposed the adaptive transfer function (ATF) method, which is based on an exogenous autoregressive model to derive GTF, and determines the peak resonance frequency of different individuals through the regression formula of brachial artery systolic pressure to correct GTF, thereby improving the accuracy of central arterial blood pressure estimation to some extent. In addition, the Omron HEM-9000AI from Japan uses a more direct central arterial blood pressure estimation method, which uses the second systolic pressure of periphery (SBP2) on the peripheral arterial blood pressure wave or the inflection point as the estimated value of central arterial systolic pressure, i.e. the SBP2 method, but the accuracy of this method is easily affected by the shape of the peripheral arterial blood pressure wave, and in certain populations (such as the elderly or patients with arteriosclerosis), the second systolic peak may not be identifiable, which may potentially affect its applicability to different populations.

[0004] After searching the prior art, it is found that Chinese patent document No. CN108937896B (publication date 2021-08-03) discloses a central arterial blood pressure measurement method and device, which comprises: measuring the blood pressure waveform of the peripheral artery changing with time; obtaining the propagation time of blood flow from the central artery to the blood pressure measurement position of the peripheral artery; and calculating the blood pressure waveform of the central artery using the blood pressure waveform of the peripheral artery and the propagation time. In the above manner, the central arterial blood pressure waveform is estimated with small calculation amount, and only the blood pressure of a single peripheral artery needs to be measured, which is relatively low in measurement difficulty and can reduce the measurement cost, but the accuracy of the central arterial blood pressure estimation needs to be further evaluated. Chinese patent document No. CN113499048B (publication date 2022-07-08) discloses a central arterial pressure waveform reconstruction system based on CNN-BiLSTM, which comprises a data acquisition control module, a radial artery pressure measurement module, a fingertip artery pressure measurement module, a data processing module, a central arterial pressure calculation module and a data display module. Through the improvement of the artificial neural network structure, an end-to-end reconstruction model of the peripheral blood pressure and the central arterial pressure is established, which effectively improves the reconstruction accuracy of the central arterial pressure waveform and the learning ability of the model to the waveform characteristics. SUMMARY

[0005] In view of the deficiencies in the prior art, the present application provides a system and method for estimating central arterial blood pressure by fusing cuff oscillatory waveform features. By analyzing the waveform features of the cuff oscillatory wave and incorporating them into the estimation of pressure wave transmission time, the individualized estimation accuracy of central arterial blood pressure is improved.

[0006] To achieve the above purpose, the present application provides a system for estimating central arterial blood pressure by fusing cuff oscillatory waveform features, comprising a signal acquisition module, an oscillatory wave amplification module, an oscillatory wave waveform feature analysis module, a pressure wave transmission time calculation module, a central arterial blood pressure calculation module and a report output module.

[0007] The signal acquisition module is arranged on an upper arm cuff and is used to acquire the oscillatory wave signal of the upper arm cuff under a certain working pressure condition and transmit the oscillatory wave signal to the oscillatory wave amplification module.

[0008] The oscillatory wave amplification module is used to filter and amplify the oscillatory wave signal to form an approximate brachial artery blood pressure wave signal and transmit it to the oscillatory wave waveform feature analysis module.

[0009] The oscillatory wave waveform feature analysis module is used to extract a plurality of waveform feature parameters from the approximate brachial artery blood pressure wave signal and transmit them to the pressure wave transmission time calculation module.

[0010] The pressure wave conduction time calculation module is configured to calculate the pressure wave conduction time from the central artery to the front edge of the upper arm cuff by using the waveform characteristic parameters , and transmit the pressure wave conduction time to the central artery blood pressure calculation module;

[0011] The central artery blood pressure calculation module is configured to perform wave decomposition, wave phase migration and wave reconstruction on the approximate brachial artery blood pressure wave signal to obtain a central artery blood pressure wave, and calculate the systolic pressure, diastolic pressure and pulse pressure of the central artery according to the reconstructed central artery blood pressure wave;

[0012] The report output module is configured to display the waveform of the central artery blood pressure wave, the systolic pressure, diastolic pressure and pulse pressure of the central artery in a graphic and text manner and output a report.

[0013] Preferably, the upper arm cuff adopts a sphygmomanometer cuff.

[0014] A method for estimating central artery blood pressure based on the fusion cuff oscillatory wave waveform characteristic estimation central artery blood pressure system of the present application, comprising the steps of:

[0015] S1: amplifying the oscillatory wave signal collected by the upper arm cuff at a specific working pressure to the scale of brachial artery blood pressure after filtering to obtain the approximate brachial artery blood pressure wave signal;

[0016] S2: extracting a plurality of waveform characteristic parameters from the approximate brachial artery blood pressure wave signal, inputting the parameter values of the waveform characteristic parameters into the equation of the pressure wave conduction time from the central artery to the front edge of the upper arm cuff of the pressure wave conduction time calculation module to calculate ; ;

[0017] S3: according to the feature that the brachial artery is almost completely blocked under the specific working pressure, decomposing the approximate brachial artery blood pressure wave signal into a forward transmission blood pressure wave component and a backward transmission blood pressure wave component; according to the wave transmission principle and , performing phase migration on the forward transmission blood pressure wave component and the backward transmission blood pressure wave component of the brachial artery respectively to obtain the forward transmission blood pressure wave component and the backward transmission blood pressure wave component of the central artery at the entrance of the subclavian artery; finally, reconstructing the central artery blood pressure wave by synthesizing the forward transmission blood pressure wave component and the backward transmission blood pressure wave component of the central artery, and performing wave analysis to calculate the systolic pressure, diastolic pressure and pulse pressure of the central artery;

[0018] S4: displaying the waveform of the central artery blood pressure wave, the systolic pressure, diastolic pressure and pulse pressure of the central artery in a graphic and text manner and outputting a report.

[0019] Preferably, the specific working pressure is higher than the brachial artery systolic pressure by 30mmHg or more.

[0020] Preferably, when the brachial artery is almost completely occluded under the specific working pressure, the blood flow in the brachial artery under the upper arm cuff is close to zero.

[0021] The present application has the following beneficial effects due to the above technical solutions:

[0022] Compared with the existing non-invasive central arterial blood pressure measurement technology, the present application is simple and fast in operation, can be fully automated, and can be implemented by professional personnel or by the examinee himself. In addition, the present application excavates and utilizes the waveform characteristics of the brachial artery blood pressure wave closely related to the cardiovascular characteristics of the individual examinee, which can significantly improve the individualized estimation accuracy of the central arterial blood pressure. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The figure is a structural schematic diagram of the system for estimating the central arterial blood pressure by fusing the cuff oscillatory wave waveform characteristics according to the embodiment of the present application.

[0024] Figure 2 The figure is a waveform diagram of the cuff oscillatory wave according to the embodiment of the present application.

[0025] Figure 3 The figure is a waveform diagram of the approximate brachial artery blood pressure wave according to the embodiment of the present application.

[0026] Figure 4 The figure is a waveform diagram of the central arterial blood pressure wave component according to the embodiment of the present application.

[0027] Figure 5 The figure is a waveform diagram of the reconstructed central arterial blood pressure wave according to the embodiment of the present application.

[0028] Figure 6 The figure is a waveform diagram of the feature points on the cuff oscillatory wave amplified according to the blood pressure scale according to the embodiment of the present application.

[0029] Figure 7 The figure is a relationship diagram of the central arterial systolic pressure estimation value and the actual value according to the embodiment of the present application.

[0030] Figure 8 The figure is a relationship diagram of the central arterial diastolic pressure estimation value and the actual value according to the embodiment of the present application. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present application are described below according to the accompanying drawings Figures 1-8 , and are described in detail, so that the functions and characteristics of the present application can be better understood.

[0032] Referring to Figures 1-8 , the system for estimating central arterial blood pressure by fusing cuff oscillatory waveform features in an embodiment of the present application comprises a signal acquisition module 2, an oscillatory wave amplification module 3, an oscillatory wave waveform feature analysis module 4, a pressure wave transit time calculation module 5, a central arterial blood pressure calculation module 6 and a report output module 7;

[0033] The signal acquisition module 2 is arranged in an upper arm cuff 1, for acquiring oscillatory wave signals of the upper arm cuff 1 under a certain working pressure condition, and transmitting the oscillatory wave signals to the oscillatory wave amplification module 3;

[0034] The oscillatory wave amplification module 3 is used for filtering and amplifying the oscillatory wave signals to form approximate brachial artery blood pressure wave signals, and transmitting the approximate brachial artery blood pressure wave signals to the oscillatory wave waveform feature analysis module 4;

[0035] The oscillatory wave waveform feature analysis module 4 is used for extracting a plurality of waveform feature parameters from the approximate brachial artery blood pressure wave signals, and transmitting the waveform feature parameters to the pressure wave transit time calculation module 5;

[0036] The pressure wave transit time calculation module 5 is used for calculating the pressure wave transit time from the central artery to the leading edge of the upper arm cuff 1 by using the waveform feature parameters , and transmitting the pressure wave transit time to the central arterial blood pressure calculation module 6;

[0037] The central arterial blood pressure calculation module 6 is used for performing wave decomposition, wave phase migration and wave reconstruction on the approximate brachial artery blood pressure wave signals to obtain a central arterial blood pressure wave, and calculating the systolic pressure, diastolic pressure and pulse pressure of the central artery according to the reconstructed central arterial blood pressure wave;

[0038] The report output module 7 is used for displaying the waveform of the central arterial blood pressure wave, the systolic pressure, diastolic pressure and pulse pressure of the central artery in the form of graphs and texts, and outputting a report.

[0039] In this embodiment, the upper arm cuff 1 adopts a sphygmomanometer cuff.

[0040] The method for estimating central arterial blood pressure by fusing cuff oscillatory waveform features in an embodiment of the present application comprises the following steps:

[0041] Step 1: measuring the systolic pressure, diastolic pressure, pulse pressure and mean pressure of the brachial artery of the left upper arm of the subject in a resting state by using an automatic blood pressure meter;

[0042] Step 2: increasing the working pressure of the upper arm cuff 1 to be higher than the systolic pressure of the brachial artery by 30 mmHg or more, and keeping it constant for at least 10 seconds, and extracting time sequence cuff oscillatory wave signals;

[0043] Step 3: Filtering the time series cuff oscillatory wave signal extracted in Step 2 (Fourier transform is used in this embodiment) to obtain a plurality of cuff oscillatory waves (an example of oscillatory wave signal in a cardiac cycle is shown in Figure 2 ) ; further amplifying the filtered cuff oscillatory wave to the same scale as the brachial artery blood pressure, so as to obtain a plurality of approximate brachial artery blood pressure waves (an example of approximate brachial artery blood pressure wave in a cardiac cycle is shown in Figure 3 ) ;

[0044] Step 4: analyzing each brachial artery blood pressure wave (i.e. the cuff oscillatory wave amplified to the scale of the arterial blood pressure) obtained in Step 3, extracting 5 waveform characteristic parameters, and using a combination equation of the characteristic parameters to calculate the pressure wave transmission time from the central artery to the front edge of the sphygmomanometer cuff ;

[0045] Step 5: decomposing each brachial artery blood pressure wave obtained in Step 3 into two blood pressure wave components of forward transmission and backward transmission, the specific steps including:

[0046] Fourier series decomposition is performed on the time-varying function of each brachial artery blood pressure wave, and each harmonic is analyzed in the frequency domain according to the following formula:

[0047]

[0048]

[0049] wherein, and respectively refer to the harmonic of the brachial artery pulsatile pressure and pulsatile flow; and are the forward transmission and backward transmission components of ; is the characteristic impedance of the brachial artery. Due to the occlusion effect of high cuff pressure on the brachial artery below the cuff, is approximately zero, so , can be decomposed into two forward transmission and backward transmission components of the same size;

[0050]

[0051]

[0052] Step 6: According to the wave propagation theory, the forward transmission ( ) and backward transmission ( ) components of the aortic pressure wave at the left subclavian artery inlet can be obtained by phase shifting the brachial artery forward transmission and backward transmission blood pressure wave components obtained in Step 5.

[0053]

[0054]

[0055] in, The pressure wave propagation time from the central artery to the leading edge of the sphygmomanometer cuff is obtained in step 4; It is the baseline angular velocity (= ),in It is the frequency of a harmonic (heart rate).

[0056] Step 7: Based on the anterior and posterior blood pressure wave components of the central arterial pressure obtained in Step 6 (see...) Figure 4 ), reconstructing the central arterial blood pressure wave (see Figure 5 The specific steps include:

[0057] First, the harmonics of each frequency are synthesized to obtain the central arterial pressure. Subharmonics:

[0058]

[0059] Then all the obtained harmonics are added together and compared with the average pressure ( The superposition generates a central arterial blood pressure wave represented in the time domain:

[0060]

[0061] in It is the first Phase angle of the subharmonic; This represents the maximum value of the harmonic (in this embodiment, the value is not less than 10). This invention assumes that the viscous pressure loss from the central artery to the occluded brachial artery is negligible. Assume it is the same as the mean brachial artery pressure measured in step 1.

[0062] In this step, multiple central artery blood pressure waves are obtained by performing wave decomposition, phase shifting, and reconstruction on multiple brachial artery blood pressure waves.

[0063] Step 8: Analyze the multiple central arterial blood pressure waves obtained in Step 7 to obtain the central arterial systolic pressure (corresponding to the first peak) and diastolic pressure (corresponding to the lowest point before the first peak).

[0064] Step 9: Take the average value of the multiple central arterial systolic and diastolic blood pressures obtained in Step 8, and calculate the pulse pressure (i.e., systolic pressure - diastolic pressure) based on the averaged systolic and diastolic blood pressures. Finally, output the central arterial blood pressure waveform and the values ​​of systolic pressure, diastolic pressure and pulse pressure.

[0065] The pressure wave propagation time from the central artery to the leading edge of the sphygmomanometer cuff, which incorporates the characteristics of the brachial artery blood pressure wave (i.e., the amplified cuff oscillation wave), is ( Optimization estimation method for )

[0066] This method aims to estimate the individualized information of the subject contained in the cuff oscillation wave. This improves the accuracy of individualized estimation of central arterial blood pressure. In the inventor's prior invention (Chinese Patent CN103479343B), Estimated based on the time difference between the two peaks of the cuff oscillation wave during the contraction period, i.e. This invention optimizes the response to cuff oscillation waves by identifying and utilizing multiple features on the cuff. The estimation is based on the waveform feature points identified and the defined feature parameters defined according to the cuff oscillation wave (i.e., the approximate brachial artery blood pressure wave) magnified according to the arterial blood pressure scale, as shown below. Figure 6 As shown in Table 1, the subscript dia represents diastolic pressure, and the subscripts p1, p2, v1, and v2 represent the first peak, second peak, first trough, and second trough, respectively. P and T represent the pressure and time corresponding to the waveform characteristic points, respectively. In this embodiment, the inventors defined five waveform characteristic parameters.

[0067] Table 1. Definition of waveform characteristic parameters of cuff oscillation wave magnified according to blood pressure scale.

[0068]

[0069] Constructed based on waveform characteristic parameters The optimized estimation formula is as follows:

[0070]

[0071] Where X represents a quadratic expression of 5 characteristic parameters, totaling 21 terms, Y is the coefficient of X, and b is a constant; This represents one-quarter of the time difference between the two contraction peaks. It is optimized. This is used for phase transfer in "Step 6" above.

[0072] To determine the values ​​of Y and b, a large amount of data needs to be used. The optimized estimation formula is used for training. In this embodiment, the inventors use virtual population numerical simulation technology based on a cardiovascular system computational model to obtain training data.

[0073] Validation based on virtual crowd data:

[0074] (1) Coupled computational model of human cardiovascular system and upper arm cuff 1

[0075] To verify the effectiveness of the central arterial blood pressure estimation method and system in this embodiment, the inventors use a coupling calculation model of the human cardiovascular system and the upper arm cuff 1 to generate virtual human data, Optimization algorithm training and central arterial blood pressure estimation accuracy verification. The human cardiovascular system model used by the present application is constructed using a 0-1 dimensional geometric multiscale modeling method, which can simultaneously describe arterial pulse wave conduction, reflection, superposition and systemic hemodynamic characteristics. Coupling with the mechanical model of the upper arm cuff 1 can realize the quantitative calculation of hemodynamic changes and cuff oscillation waves during the inflation and deflation process of the cuff. At the same time, by adjusting the parameters in the cardiovascular system model, various cardiovascular physiological or pathological states can be represented, thereby providing an effective tool for simulating virtual humans with different cardiovascular characteristics and constructing a large-scale virtual human database.

[0076] (2) Calculation conditions

[0077] In order to generate virtual individuals with different cardiovascular physiological and pathological characteristics, and cover different cardiovascular functional states from young people to old people, this method selects six model parameters for adjustment, which are aortic stiffness ( ), brachial artery stiffness ( ), left ventricular contractility ( ), cardiac cycle ( ), total peripheral vascular resistance ( ) and height ( ). The variation ranges of the above parameters are shown in Table 2. The parameters with subscript "0" in the table represent the normal reference value of the parameter (corresponding to a healthy young person of 25 years old). Latin hypercube sampling is used to randomly sample the values of the above parameters within the specified range, to construct 500 virtual individuals with different cardiovascular physiological and pathological characteristics, and randomly select 80% of the samples as the training set and 20% of the samples as the test set.

[0078] Table 2 Variation range table of cardiovascular system model parameters

[0079]

[0080] (3) Central arterial blood pressure estimation error evaluation

[0081] Based on the training set data The values of the coefficients Y and b in the optimization estimation formula are used for central arterial blood pressure estimation and error evaluation in the test set. The training set data includes cuff oscillation wave, brachial artery blood pressure and central arterial blood pressure, wherein the brachial artery blood pressure is used to amplify the cuff oscillation wave to obtain an approximate brachial artery blood pressure wave, and the central arterial blood pressure (i.e. the actual value) is the gold standard for evaluating the central arterial blood pressure estimation error. The difference between the central systolic pressure, diastolic pressure and pulse pressure estimated by the method and steps of the present application and the true value is defined as the estimation error, which is respectively represented by , and .

[0082] Figure 7 and Figure 8 The estimated values of the central systolic pressure and diastolic pressure in the test set are significantly correlated with the actual values, wherein the correlation coefficient R of the systolic pressure is 0.995, p<0.0001; and the correlation coefficient R of the diastolic pressure is 0.998, p<0.0001.

[0083] Statistical analysis is performed on the , and of 100 virtual human samples in the test set, and the results are as follows: , -0.14±0.75mmHg (mean±standard deviation); , -0.44±0.29mmHg; , 0.30±0.76mmHg, all errors meet the international standard of blood pressure measurement tolerance.

[0084] The above embodiments of the present application are described in detail with reference to the accompanying drawings, and those of ordinary skill in the art can make various changes to the present application according to the above description. Therefore, some details in the embodiments should not be construed as limiting the present application, and the scope of the present application will be defined by the appended claims.

Claims

1. A system for estimating central arterial blood pressure by integrating cuff oscillation waveform characteristics, characterized in that, It includes a signal acquisition module, an oscillation wave amplification module, an oscillation wave waveform feature analysis module, a pressure wave propagation time calculation module, a central arterial blood pressure calculation module, and a report output module; A signal acquisition module is installed on an upper arm cuff to acquire the oscillation wave signal of the upper arm cuff under a specific working pressure condition and transmit the oscillation wave signal to the oscillation wave amplification module, wherein the specific working pressure is more than 30 mmHg higher than the brachial artery systolic pressure. The oscillation wave amplification module is used to filter and amplify the oscillation wave signal to form an approximate brachial artery blood pressure wave signal, and transmit it to the oscillation wave waveform feature analysis module. The oscillating wave waveform feature analysis module is used to extract five waveform feature parameters from the approximate brachial artery blood pressure wave signal and transmit them to the pressure wave conduction time calculation module. The pressure wave transit time calculation module is configured to calculate a pressure wave transit time from the central artery to the front edge of the upper arm cuff using the waveform characteristic parameters and transmit the pressure wave transit time to the central arterial blood pressure calculation module, wherein the pressure wave transit time is calculated according to the waveform characteristic parameters The optimization estimation formula is as follows: X represents a quadratic expression of the five characteristic parameters, Y is a coefficient of X, and b is a constant; represents one fourth of the time difference between two systolic peaks; is an optimized for subsequent phase migration, wherein the definitions of the five waveform characteristic parameters are as follows: , = , = , = , = , P and T represent pressure and time corresponding to the waveform characteristic points respectively, subscript dia represents diastolic pressure, subscripts p1, p2, v1, and v2 represent the first wave peak, the second wave peak, the first wave valley, and the second wave valley respectively, represents a pressure difference between and The central artery blood pressure calculation module is used to perform wave decomposition, wave phase shifting and wave reconstruction on the approximate brachial artery blood pressure wave signal to obtain the central artery blood pressure wave, and to calculate the systolic blood pressure, diastolic blood pressure and pulse pressure of the central artery based on the reconstructed central artery blood pressure wave; The report output module is used to display the waveform of the central arterial blood pressure wave, the systolic pressure, diastolic pressure and pulse pressure of the central artery in graphics and text and output a report.

2. The system for estimating central arterial blood pressure from a fusion cuff oscillatory waveform signature of claim 1, wherein, The upper arm cuff is a blood pressure monitor cuff.

3. A method for estimating central arterial blood pressure based on the fusion cuff oscillatory waveform characteristics of the system described in claim 2, comprising the steps of: S1: The oscillation wave signal collected by the upper arm cuff under the specific working pressure is filtered and amplified to the brachial artery blood pressure scale to obtain the approximate brachial artery blood pressure wave signal; S2: extracting 5 waveform feature parameters in the approximate brachial artery blood pressure wave signal, inputting the parameter values of the waveform feature parameters into the central artery to the upper arm sleeve front edge pressure wave transmission time of the pressure wave transmission time calculation module in the equation, calculating ; S3: According to the feature that the brachial artery is almost completely closed under the specific working pressure condition, the approximate brachial artery blood pressure wave signal is decomposed into a forward transmission blood pressure wave component and a backward transmission blood pressure wave component; according to the wave transmission principle and , the forward transmission blood pressure wave component and the backward transmission blood pressure wave component of the subclavian artery are respectively subjected to phase migration to obtain the forward transmission blood pressure wave component and the backward transmission blood pressure wave component of the central artery at the subclavian artery entrance; finally, the central artery blood pressure wave is reconstructed by synthesizing the forward transmission blood pressure wave component and the backward transmission blood pressure wave component of the central artery, and wave analysis is performed to calculate the systolic pressure, diastolic pressure and pulse pressure of the central artery; S4: Display the waveform of the central arterial blood pressure wave, the systolic pressure, diastolic pressure, and pulse pressure of the central artery graphically and output a report.

4. The method for estimating central arterial blood pressure based on the fusion of cuff oscillatory wave waveform characteristics according to claim 3, characterized in that, When the brachial artery is almost completely blocked under the specific working pressure conditions, the blood flow in the brachial artery below the upper arm cuff is close to zero.

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