79 results about "Pulse Wave Transit Time" patented technology

A blood pressure monitoring apparatus which continuously estimates and monitors the blood pressure by using the pulse wave propagation time can accurately estimate the blood pressure. While an estimated blood pressure is continuously calculated by using the pulse wave propagation time, the correlation between the pulse wave propagation time and the interval between feature points contained in two consecutive heart beat waveforms of an electrocardiogram is monitored. If the correlation is reversed, the blood pressure is actually measured, and the estimated blood pressure is corrected on the basis of the difference between the estimated blood pressure and actually measured blood pressure.

A blood pressure monitoring system includes a blood pressure measurement device for measuring blood pressure using a cuff, a memory for storing an externally inputted pulse wave propagation time fluctuation threshold, a time interval detection reference point detection section for detecting a time interval detection reference point in a pulse wave on the side of aortae of a living organism, a pulse wave detection section for detecting a pulse wave on the side of peripheral blood vessels appearing with a time lag with respect to the pulse wave on the side of aortae, a pulse wave propagation time measurement section for measuring a pulse wave propagation time based on respective detected outputs from the time interval detection reference point detection section and the pulse wave detection section, an operation device for calculating a pulse wave propagation fluctuation from two measured pulse wave propagation times, a judgment device for judging whether or not the calculated pulse wave propagation time fluctuation exceeds the pulse wave propagation time fluctuation threshold read from the memory, and a control device for controlling the blood pressure measurement device based on an output of the judgment device so that the blood pressure of a subject is measured using the cuff.

A first member is adapted to measure an electrocardiogram of a patient. A second member is adapted to measure a peripheral pulse wave of the patient. A first calculator calculates a pulse wave propagation time (PWTT) and a heart rate (HR) of the patient based on the electrocardiogram and the peripheral pulse wave. A second calculator calculates a cardiac output (CO) of the patient with an equation of CO=(αK·PWTT+βK)·HR, where α, β and K are coefficients inherent to the patient.

The invention relates to a combined variability index testing method of cardiovascular system and the testing device. The testing method comprises the following steps: (1) collecting the electrocardio-signal, the phonocardio-signal and the pulse signal of radial artery; (2) performing analog-to-digital conversion to the three signals to form the signal oscillogram; (3) identifying and extracting the characteristic point of each signal; (4) constructing the time series RR of electrocardio-period, the electromechanical delay time series and the pulse wave propagation time series of the combined variability index; (5) testing the validity of each time series; (6) calculating the heart rate variability, the electromechanical delay variability and the pulse wave propagation time variability; and (7) calculating the combined variability index of angiocarpy AV. The testing device comprises an electrocardio-signal testing module, a phonocardio-signal testing module, radial artery pulse signal testing module, an analog-to-digital converting device and a computer. The invention enables to reflect the physiological and pathological status of the human cardiovascular system well and has the advantages of high discriminating degree and wide clinic application value.

In blood pressure monitoring apparatus which continuously estimates and monitors blood pressure by using the pulse wave propagation time, blood pressure fluctuation can be accurately estimated. If both blood pressure estimated from the pulse wave propagation time and a waveform parameter obtained from the accelerated pulse wave have abnormal values, it is determined that the blood pressure is truly fluctuating, and blood pressure measurement by another method, e.g., blood pressure measurement using a cuff is performed.

The invention provides an independently researched and developed continuous dynamic blood pressure monitoring device and method based on pulse wave transit time (PWTT) and pulse wave transit velocity (PWV). According to the device, an electrocardiosignal collecting module (104) is arranged on a main case (101) in a wristwatch form, a pulse wave signal collecting module (103) is arranged at the position, corresponding to the wrist radial artery, of a wristband (102), and the electrocardiosignal collecting module (104) and the pulse wave signal collecting module (103) are in signal connection with a control module (105). The device and algorithm can obtain pulse waves in real time, the problem that in-vitro heart pulse waves are inconvenient to obtain is solved, the method for rapidly and accurately obtaining the cardiac ejection time point is provided, and the method is an important part of continuous dynamic blood pressure monitoring.

The blood pressure monitoring apparatus includes blood pressure measuring device for measuring the blood pressure employing a cuff, pulse wave propagation time measuring device for measuring the pulse wave propagation time, hemodynamics measuring device for measuring the hemodynamics, and control device for controlling the blood pressure measuring device on the basis of a change in pulse wave propagation time measured by the pulse wave propagation time measuring device and a change in hemodynamics measured by the hemodynamics measuring device, wherein the control device controls the blood pressure measuring device to measure the blood pressure on the basis of the amount of change and change trend in the pulse wave propagation time measured by the pulse wave propagation time measuring device, and the amount of change and change trend in the hemodynamics measured by the hemodynamics measuring device.

The invention discloses a time synchronization method and device of a wireless sensing system based on the distributed BLE communication protocol. The method comprises the following steps: calculating a time interval; judging whether time differences are synchronous or not; sending the current time, measurement data, and measurement time information corresponding to the measurement data; receiving the current time information, the measurement data and the measurement time information corresponding to the measurement data which have been sent and calculating a time difference between a master node and a slave node; and adjusting the measurement data of the slave node according to measurement time for which a master node clock is used as a reference. The time synchronization method and device of the wireless sensing system based on the distributed BLE communication protocol and an electronic sphygmomanometer of the device have the advantages that high requirements for the time synchronization of an ECG signal and a PPG signal during human blood pressure testing through pulse wave transit time (PWTT) can be satisfied, so that the ECG signal and the PPG signal are on the same time axis, and the accurate PWTT can be further obtained.

The invention discloses a device and method for measuring pulse wave velocity of human or mammal. The device comprises at least two sensors connecting with a signal processing element, wherein at least one of the first and second sensors is a diffused silicon pressure sensor. The signal processing element comprises amplifying circuits, a filter circuit, an analog to digital conversion circuit, and a main control circuit in sequential connection. The sensors are connected to the corresponding amplifying circuits respectively. The signal processing element also comprises signal separation circuit for separating transducer spikes. The method comprises obtaining maximum pulse signals, simultaneous recording two pulse wave signals with certain distance Delta s, abstracting characteristic reference point, calculating time interval difference Delta t of the signals, and calculating the pulse wave velocity. The device has the advantages of high safety, convenient operation, and good low-frequency response. The method has the advantages of reduced calculation amount, determined reference point, and high accuracy.

The invention discloses a method for obtaining the pulse wave velocity of aorta by using pulse wave of radial artery, relating to the field of cardiovascular medicines in biomedicine. In the invention, based on the waveform at one point of radial artery, the pulse wave transit time of the aorta can be analyzed and obtained, further, the pulse wave velocity of the aorta can be calculated, and the calculation formula is as follows: the pulse wave velocity of the aorta (aoPWV)is equal to a result that the time difference (delta t) between the main wave and the reflected wave of the pulse wave ofthe radial artery is divided by two times of the length of the aorta, that is, aoPWV=2L/delta t; in the invention, the transmit theory of the pulse wave is firstly applied in the calculation of the PWV, two acquisition points are simplified to form one point, the acquisition position is changed to the radial artery from carotid and femoral artery, signal acquisition difficulty is decreased, the testing procedure is simplified, and no hazard exists. A pulse measuring device in the invention is a pulse clip fixed-pulse sensor, so that the acquisition of the pulse wave of the radial artery is easier; besides, the operation is convenient, and the requirement for operators is low.

A pulse wave transit time measurement device includes a pulse wave transit time calculator that calculates a pulse wave transit time based on a peak time difference between an electrocardiographic signal and a pulse wave signal, a posture classifier that classifies time serial data of the pulse wave transit time based on a posture detected by an acceleration sensor, and a fluctuation identifier that sets a reference posture from among classified postures, corrects, in conformity with the reference posture, the time serial data of the pulse wave transit time classified into the posture different from the reference posture, and determines fluctuations in the pulse wave transit time based on the time serial data of the pulse wave transit time in the reference posture and the time serial data of the pulse wave transit time having being corrected.

The invention discloses a measuring method and a measuring device for pulse wave propagation time. The method comprises: synchronously collecting a pulse wave signal and an electrocardiogram signal ofa measured person, extracting characteristic points of the pulse wave signal and the electrocardiogram signal, and calculates a pulse conduction time PAT. The pre-ejection PEP was calculated according to the electrocardiogram signal. The pulse wave propagation time (PTT) is obtained by subtracting the pre-ejection PEP from the calculated pulse propagation time (PAT). The invention eliminates theinfluence of the pre-ejection period and improves the measurement accuracy of the pulse wave propagation time PTT.

The present invention provides a biological information measurement apparatus, a biological information measurement system, a biological information measurement method, and program. The biological information measurement apparatus includes a biological information acquisition unit configured to acquire at least first waveform information relating to a first waveform representing a beat of a measurement subject measured at a first measurement site, and as second waveform information relating to a second waveform representing the beat of the measurement subject measured at a second measurement site different from the first measurement site, information relating to a timing corresponding to a second feature which is a characteristic feature of the second waveform, and a pulse wave transit time calculation unit configured to, based on the first and second waveform information, calculate a pulse wave transit time, which is a difference between a timing corresponding to a first feature which is a characteristic feature of the first waveform and the timing corresponding to the second feature which is a characteristic feature of the second waveform.

This blood pressure measuring device includes: first and second electrodes which contact the body surface near an artery; an electrocardiogram measuring means which measures a potential difference between the first electrode and the second electrode and obtains a first time at which at least a prescribed portion is generated in an electrocardiogram; a pulse wave detecting means which detects pulse wave information from the body surface near the artery; a pulse wave measuring means which obtains, from the pulse wave information, a second time at which a prescribed portion is generated in the pulse wave; and a blood pressure estimating means which calculates a pulse wave propagation time from the first time and the second time, and calculates an estimated blood pressure on the basis of a relationship between the pulse wave propagation time, a predefined pulse wave propagation time, and a blood pressure value.

The invention provides a dynamic blood pressure monitoring system and a dynamic blood pressure monitoring method based on a radial artery biosensor technology. The dynamic blood pressure monitoring system comprises a main processor, a watch and a biosensor arranged in the watch. The biosensor comprises a radial artery biosensor embedded in a watch belt, a stainless steel electrode embedded in the bottom of the watch and a stainless steel electrode arranged in a watch shell. The radial artery biosensor is used for measuring pulse waveforms of the radial artery. The stainless steel electrode embedded in the bottom of the watch is used for contacting with the wrist to measure ECG (electrocardiogram) waves of the hand. The stainless steel electrode arranged in the watch shell contacts with fingers during measurement to measure ECG waves of the other hand. Through pulse waveform data and ECG signals which are captured synchronously, blood pressure values are calculated dynamically according to the pulse wave transit time (PWTT) principle. The biosensor internally arranged in the watch belt measures the radial artery of the wrist dynamically, captures pulse waves of the radial artery, and performs high-accuracy calculation on the blood pressure values according to the synchronously-measured ECG signals of the two hands.

The invention relates to a method of operating a long-term blood pressure measurement device having a measurement sensor for detecting a pulse wave signal, having a measurement sensor for body current signals, having a pressure cuff for a non-invasive determination of the blood pressure, having a control and evaluation unit for determining blood pressure values, on the one hand from signals acquired by means of the pressure cuff (pressure cuff signals), and, on the other hand from a pulse wave transit time that is derived from body current signals and pulse wave signals, and having a memory for storing blood pressure values.

The invention relates to a blood pressure calculation method and a blood pressure measuring device. The method includes the following steps: obtaining synchronously collected pulse wave signals and electrocardiosignals, extracting pulse wave characteristic parameters based on the pulse wave signals, extracting pulse wave transit time based on the electrocardiosignals and the pulse wave signals, and calculating blood pressure based on a linear model including the pulse wave transit time and the several pulse wave characteristic parameters. The device includes a sensor module, a signal processing module and a display module. A data processor in the signal processing module adopts the method of the invention for data processing and calculation to obtain blood pressure data. By taking variousfactors into consideration, the accuracy of blood pressure measurement and continuous blood pressure monitoring can be improved.

A biological information monitor includes: a first measuring unit which measures a pulse wave propagation time of a patient; a second measuring unit which measures a blood pressure of the patient; a calculating unit which calculates an estimated blood pressure value of the patient based on the pulse wave propagation time of the patient; a setting unit which sets a threshold; and a determining unit which compares the estimated blood pressure value with the threshold. The second measuring unit is activated to measure the blood pressure of the patient at least one of at time intervals and at a time when an operator operates the second measuring unit, and the second measuring unit is activated to measure the blood pressure of the patient by the determining unit based on the comparison result.

A pulse wave transit time measurement device includes a neck band, a pair of electrocardiographic electrodes detecting an electrocardiographic signal, a photoplethysmographic sensor detecting a pulse wave signal, and a pulse wave transit time calculator calculating a pulse wave transit time based on a peak time difference between the electrocardiographic signal detected by the electrocardiographic electrodes and the pulse wave signal detected by the photoplethysmographic sensor. The photoplethysmographic sensor is positioned in or substantially in a central region of the neck band at a location at which the photoplethysmographic sensor is in contact with a neck of a user at or near a midline of the neck on the backside when the neck band is worn around the neck of the user.

The Invention relates to a method for determining vital parameters of a human body by means of a device (10) with at least one optical recording unit (11) and a computinig unit (12), said method comprising the following steps: recording a sequence of Individual image data of a single limited area of the skin (30) of the human body by means of the optical recording unit (11); evaluating the image data, including determining a pulse wave transit time; and determining vital parameters of the human body from the image data by means of the computing unit (12). The invention further relates to a method for authenticating a person and to a method for identifying a reaction of a person.