Improved collection of personal health data

Abstract

The invention disclosed herein relates to improvements in personal health data collection. The invention also relates to a personal health monitor (PHM), which can be a personal hand-held monitor (PHHM), comprising a signal acquisition device (SAD) and a processor and its attendant screen and other peripherals. The SAD is adapted to acquire signals which can be used to derive a measurement of one or more parameters relating to the health of the user. The computational and other facilities of the PHM integrated with the SAD are adapted to control and analyse the signals received from the SAD. The personal health data collected by the SAD can include data relating to one or more of: blood pressure; pulse; blood oxygen level (Sp02); body temperature; respiratory rate; electrocardiogram; cardiac output; cardiac functional timing; arterial stiffness; tissue stiffness; hydration; concentration of a blood constituent (such as glucose or alcohol); blood viscosity; blood pressure variability; and the identity of the user.

Description

Technical Field

[0001] The present invention disclosed herein relates to improvements in the collection of personal health data. The invention also relates to a personal health monitor (PHM), which may be a personal handheld monitor (PHHM) comprising a signal acquisition device (SAD) and a processor, along with an attached screen and other peripheral devices. The SAD is adapted to acquire signals that can be used to derive measurements of one or more parameters related to the user's health. The calculations and other facilities of the PHM connected to or integrated with the SAD are adapted to control and analyze the signals received from the SAD. The personal health data collected by the SAD may include data related to one or more of the following: blood pressure; pulse; blood oxygen level (SpO2); body temperature; respiratory rate; electrocardiogram; cardiac output; cardiac function timing; arterial stiffness; tissue stiffness; hydration; concentration of blood components (such as glucose or alcohol); blood viscosity; blood pressure variability; and user identity.

[0002] General background technology

[0003] Many methods for measuring blood pressure are known, such as the oscillometric method (which measures pressure using a cuff), the PPG optical method (which measures the absorption of light by blood in an artery), the auscultatory method (which uses changes in sound as blood flows through an artery), or the direct method (which uses ultrasound imaging or any other method that detects the difference in lumen area or size as an artery moves from a blocked state to a patent state).

[0004] WO2013 / 001265 (PCT1) discloses a personal handheld monitor (PHHM) in which a signal acquisition device (SAD) is integrated with a personal handheld computing device (PHHCD) such as a cellular phone, suitable for measuring, for example, blood pressure or one or more of several other health-related parameters. The SAD is adapted to be pressed against a body part or have a body part pressed against it, for example, the side of a finger. This allows for cuffless occlusion measurements. The SAD also includes an electrical sensor that can be used to detect a 1-lead electrocardiogram between both hands.

[0005] WO2014 / 125431 (PCT2) discloses several improvements to the invention described in PCT1, including the use of: a gel for measuring pressure; a saddle-shaped surface that interacts with body parts; correction of the artery’s position relative to the actual device; and the use of interactive instructions for the user.

[0006] WO / 2014 / 125355 (PCT3) discloses improvements to the noninvasive blood analysis disclosed in PCT1, including improvements to the specificity and accuracy of the measurement.

[0007] WO2016 / 096919 (PCT4) discloses several further improvements to the inventions described in PCT1 and PCT2, including: improvements to the gel and pressure sensing means; the use of mathematical procedures and other signal processing inventions for extracting blood pressure; means for identifying the user; improvements to the electrical system used for measurement; and several aspects of the testing and calibration of the device. PCT 4, page 11, lines 5-8, discloses that for performing a pulse wave assessment (PWA), a camera can be used to detect the arrival of the pulse through changes in skin color. For example, this allows for the identification of differences in pulse timing between the face and the fingers.

[0008] WO2017 / 140748 (PCT5) discloses further improvements for extracting blood pressure and several other health-related parameters that can be derived from measurement data.

[0009] WO2017 / 198981 (PCT6) discloses improvements to the invention disclosed in PCT3, according to which the device can be constructed using small and inexpensive components.

[0010] WO2019 / 211807 (PCT7) discloses several improvements to the invention disclosed above, including the following aspects: the device is adapted to use arteries in the fingertips or cheeks, both of which result in an increase in the variation of applied pressure compared to earlier applications.

[0011] PCT1 through PCT7 were all filed in the name of Leman Micro Devices SA, and are therefore collectively referred to as "Leman applications". The entire contents of the Leman applications are hereby incorporated herein by reference.

[0012] The inventions disclosed in Leman's application are effective, fairly accurate, easy to use, and can be integrated into cellular phones. Cellular phones are manufactured in the hundreds of millions, and the price of their components is crucial. These inventions enable blood pressure measurement to be reduced to a level acceptable for cellular phones, in part because they eliminate the expensive and heavy components in traditional devices that ensure constant pressure application.

[0013] The surface area of ​​an artery changes between diastole and systole because the pressure difference between the blood inside the artery and the surrounding tissues changes. This causes stretching of the arterial wall. If this stretching can be detected and measured, diastolic and systolic blood pressure can be determined without the use of a cuff.

[0014] Therefore, this cuffless measurement principle offers numerous benefits to users and global health, but it requires the user to actively press the device onto a body part, or for the body part to press onto the device in a controlled manner. This invention mitigates these drawbacks by allowing for shorter measurement times and compensating for pressure fluctuations caused by the pressing action. Additional measurement capabilities using the same set of sensing devices are also disclosed.

[0015] This invention relates to several improvements to measurement by creating new features for the invention described in the Leman application.

[0016] First aspect of background There are three main types of automated non-invasive blood pressure measurement devices: occlusion devices; pulse wave velocity (PWV) devices; and pulse wave analysis (PWA) devices.

[0017] Occlusion devices have found that pressure must be applied outside the artery to equalize the blood pressure within it. These devices can provide absolute blood pressure measurements without the need for personal calibration. Oscilloscope-based automated cuff devices utilize this occlusion principle. Leman's application discloses a unique cuffless occlusion device, which is utilized in the first aspect of this invention.

[0018] Pulse wave velocity (PWV) devices measure characteristics related to the speed at which pressure waves travel along an artery, which in turn relates to the arterial stiffness and the difference between the pressure of blood within the artery and the pressure of tissues outside the artery. These are relative measurements of blood pressure, and therefore, after calibration for the user, can be used to detect changes in blood pressure. PWV is well-known; it works by estimating the speed of pressure waves traveling along an artery by dividing the distance between two points in the arterial system by the time it takes for the pulse to travel between those two points (pulse conduction time, PTT). There are two methods to do this: (i) The time it takes for the pulse to travel from the heart to the distal end is measured by using an electrical sensor to detect an electrical signal indicating the onset of heartbeat and using an optical sensor to detect the time it takes for the pressure pulse to reach the distal end; the time interval between the arrival of the electrical signal and the pulse includes the delay between the electrical signal and the heart contraction, referred to as the pre-ejection phase (PEP); and (ii) Use two or more optical sensors to detect the arrival of the pulse at different points and measure the PTT between them.

[0019] Pulse wave analysis (PWA) devices analyze the shape of a pulse wave measured at the distal end of the pulse. This is typically measured by an optical sensor, but can also be measured using an ultrasonic sensor, a displacement-detecting sensor, or a pressure sensor. PWA is related to pulse wave velocity. PWA devices analyze the waveform of a signal related to arterial area to infer blood pressure. They can do this by explicitly estimating PWV (e.g., see Tavalali et al., Scientific Reports 8, article number: 1014, 2018) or by direct analysis of the contribution of the velocity implied therein (e.g., see Gircys et al., Applied Sciences, 2019, 9, 2236; doi:10.3390 / app9112236). PWA devices, after being calibrated by the user, can be used to detect changes in blood pressure.

[0020] Another feature of PWA and PWV devices is that they can be adapted to provide instantaneous estimates of blood pressure with each heartbeat. This is useful for providing biofeedback to the user and allowing the user to arrive at estimates of short-term blood pressure variability.

[0021] The first aspect of the invention relates to a novel method that combines the advantages of a occlusion device, a pulse wave velocity (PWV) device, and a pulse wave analysis (PWA) device to create a device that is more accurate and / or easier, faster to use, and / or provides additional measurement capabilities.

[0022] First aspect of the invention Leman's application discloses a device capable of performing plugging, PWV, and PWA measurements. Leman's application also discloses the ability to combine two or more measurements for higher accuracy. A table on page 16 of PCT1 indicates: "The combination may not be just a simple average; the process may find the most likely value based on all available information, using techniques such as Bayesian estimators to consider all the data, including the variations between pulses."

[0023] The first aspect of the invention goes beyond combining two independently identified values ​​and using the combination to measure blood pressure or another health-related parameter in a way that is more accurate, easier, or faster than measurements that can be performed according to the disclosure in PCT1.

[0024] According to this aspect of the invention, it has been found that it is possible to use occlusion devices, PWV devices, and PWA devices in various combinations to reduce errors in the measurement of blood pressure and other health-related parameters that may result from their use, and to make it easier and faster to obtain such measurements.

[0025] Various kits and apparatuses of the first aspect of the present invention are disclosed in some embodiments described below.

[0026] Preferred kits and apparatuses in this respect are illustrated in the following embodiments.

[0027] Regarding embodiments of a kit comprising two devices and an analytical means, the analytical means may be a completely independent item, exist entirely as part of one, the other, or both of the devices, or exist partly as part of one or the other of the devices and partly exist as an independent item.

[0028] In any kit of the first aspect of the invention, the analytical means may receive signals from other components in the kit or integrated device by any suitable means (such as via cable, Wi-Fi, Bluetooth or any other suitable means), as is well known to those skilled in the art.

[0029] In particular, it has been found that devices of the type disclosed in the Lyman application can be adapted to perform the necessary measurements for plugging, PWV and PWA measurements, and to combine two or more measurements cooperatively to improve the accuracy of the measurements or to increase the processing speed of the devices disclosed in the Lyman application.

[0030] Preferably, the body part used for contact is the finger, more preferably the fingertip, but any part of the body with a contactable artery (such as the face, neck, toes, wrist, etc.) can also be used. Similarly, PWV and PWA measurements can be performed between any two separate body parts, for example, measuring the start time at the heart with an electrical sensor, measuring the end time at the finger with an optical sensor, or observing the start time at the face with a camera to measure the end time at the finger with an optical sensor.

[0031] Preferably, the means of contact do not include a cuff.

[0032] Preferably, the kit or device is adapted to provide the user with instructions to press harder or softer, creating a range of pressure applied.

[0033] Changes in arterial area can be detected using optical sensors, which measure the absorption of light by the blood in the arteries in a manner similar to that of a pulse oximeter.

[0034] The second aspect of the background In the device disclosed in Lyman's patent application, the pressure used to block the artery is generated by the user's muscle movements. These movements inevitably fluctuate. Fluctuations between heartbeats are not critical, as the LMD device's algorithm can accept data in any order, but fluctuations within the heartbeat can cause significant errors.

[0035] Traditional blood pressure measurement devices assume that the pressure in the tissues surrounding the arteries is constant during a heartbeat, or at least constant between diastole and systole. They also assume that the pressure in the tissues surrounding the arteries is the same as the applied pressure. Therefore, blood pressure can be easily estimated by plotting the relationship between attribute values ​​of changes in arterial area and the applied pressure. Various proprietary algorithms are used to derive diastolic and systolic blood pressure from this curve.

[0036] This method is less effective and therefore less accurate in measuring blood pressure if the assumption that the pressure in the tissue surrounding the artery is constant does not hold. This is likely because changes in the area of ​​the artery during a heartbeat cause significant changes in pressure in the tissue surrounding it. This occurs with any device, but in practice, it is negligible for devices like a traditional brachial cuff. However, this change becomes more pronounced if the artery occupies a large portion of the volume of the tissue being measured (e.g., the side of a finger is used for measurement). This change is further amplified if the mechanism applying pressure to the tissue surrounding the artery does not exert constant pressure (e.g., if it is generated by a person pressing the device against a body part or vice versa); the person's muscles may sway with a time constant shorter than that of a heartbeat.

[0037] This limitation restricts the use of methods for measuring blood pressure that may be cheaper, more accurate, easier to use, or smaller than known devices, such as those disclosed in the Leman application. In these, the pressure used to block the artery is generated by the user's muscle movements. These movements inevitably fluctuate. Fluctuations between heartbeats are not critical because the algorithm in the device disclosed in the Leman application can accept data in any order, but fluctuations within the heartbeat can introduce significant errors.

[0038] The second aspect of the invention overcomes or greatly reduces the limitations caused by pressure variations, thus bringing benefits to a range of methods for measuring blood pressure (such as those disclosed in the Leman application).

[0039] Second aspect of the invention A second aspect of the invention relates to a method for reducing errors caused by pressure variations between a device and a body part using isobaric analysis.

[0040] A second aspect of the invention relates to a device for measuring blood pressure, which measures a property relating to changes in arterial area as a function of pressure applied to the artery, and is adaptable to changes in pressure applied during a single heartbeat.

[0041] Attributes related to area changes can be changes in measured cuff pressure (oscillometric method), changes in light absorption (optical method), changes in sound (auscultation method), or changes in the area or size of the lumen of an artery as it becomes open (direct method).

[0042] Therefore, a second aspect of the present invention provides an apparatus for non-invasive blood pressure measurement, the apparatus comprising means for measuring changes in the area of ​​the luminal artery during a heartbeat, means for applying pressure to a body part containing an artery, and means for measuring the instantaneous pressure applied to the body part containing an artery, wherein: Blood pressure is determined by analyzing changes in arterial area as a function of instantaneous pressure applied to body parts containing arteries; and The device is adapted to make accurate measurements of blood pressure by compensating for any significant changes in instantaneous pressure applied to body parts containing arteries during a heartbeat.

[0043] Preferably, the method used to measure the change in the area of ​​the luminal artery during heartbeat is oscillometric analysis.

[0044] Alternatively, optical methods can be used to measure changes in the area of ​​the luminal arteries during heartbeats.

[0045] Alternatively, auscultation is used to measure changes in the area of ​​the luminal arteries during heartbeats.

[0046] Another alternative method for measuring changes in the area of ​​the luminal arteries during heartbeat is ultrasound.

[0047] Preferably, the means for compensating for changes in instantaneous pressure applied to body parts containing arteries during heartbeats uses a separate analysis of values ​​obtained by means of measuring changes in the luminal arterial area during diastole and systole during heartbeats.

[0048] Preferably, a curve fitting algorithm is used to create two parametric curves representing the values ​​of diastole and systole, analyzed separately. The curve fitting algorithm can be the Loess algorithm.

[0049] Preferably, the difference between the two parametric curves is used to create a set of spurious heartbeats that apply the same instantaneous pressure to the body part containing the artery during diastole and systole. If the instantaneous pressure applied to the body part containing the artery does not change significantly during the heartbeat, this set of spurious heartbeats can be analyzed in the same way as real heartbeats.

[0050] Preferably, blood pressure is determined by analyzing the timing of changes in arterial area as a function of instantaneous pressure applied to a body part containing an artery.

[0051] The first and second aspects of the invention can work synergistically, as the improved accuracy of the second aspect makes the occlusion measurement of the first aspect more reliable. It is also evident that, although both aspects were invented in the context of the Leman application, their utility extends more broadly to other forms of blood pressure measurement devices.

[0052] The third aspect of the background The device disclosed in the Leman application has several sensors that create a rich dataset. These sensors can be used collaboratively to improve the accuracy, ease of use, or functionality of the device.

[0053] A third aspect of the invention is to improve or expand the scope of collected personal health data by utilizing the features of the data collected or potentially collected by the device disclosed in the Leman application.

[0054] The two specific opportunities are: Using dynamic changes in PPG data to determine blood viscosity; this is increasingly recognized as a valuable diagnostic vital sign (e.g., see "Why Blood Viscosity Testing May Be a Key Aspect of Covid-19 Treatment," *Journal of Invasive Cardiology*, August 3, 2020); and The proximity of the PPG signal detection device to a body part can be used; if the distance between the sensor and the body part is known, then measuring temperature by detecting the thermal radiation of the body part can be more accurate.

[0055] Third aspect of the invention PPG signals are strongly influenced by both the changes in the lumen area of ​​arteries during heartbeats and the absorption of light by the tissues surrounding the arteries (including blood in local blood vessels (arterioles and veins)). When the pressure between the body part and the SAD changes, the tissue deforms, and blood flows in or out of the local blood vessels. The time constant of this deformation and blood flow is typically several seconds.

[0056] The value of this time constant depends in part on the viscosity of the blood. The magnitude of the PPG signal variation depends on the shape and composition of the irradiated body part and the wavelength of the PPG light. The wavelength determines the relative absorption due to oxygenated blood, deoxygenated blood, and tissues.

[0057] The third aspect of the invention utilizes both high-frequency PPG signals (fluctuations caused by changes in the lumen area of ​​the artery) and low-frequency PPG signals (obtained by filtering high-frequency signals). It also utilizes the capability of the LMD device to instruct the user to establish controlled applied pressure between the device and the body part, and to vary that pressure as needed.

[0058] The relationship between high-frequency and low-frequency signals obtained by controlling applied pressure and blood viscosity must be determined empirically. This can be accomplished using supervised machine learning, with the training dataset including: High and low frequency signals measured under various controlled applied pressure modes; and Blood viscosity measured using traditional invasive devices such as the Benson viscometer.

[0059] PPG optical systems can also be used as proximity detectors. In the device according to Leman's application, the LED emitting light and the photodetector detecting the light are typically about 6 mm apart. If a reflective or scattering surface moves toward the device when the LED is lit, the received signal will peak around this distance. Simultaneously, the ambient signal caused by background light will decrease due to shadows as the device approaches the surface.

[0060] The features of the third aspect of the invention are disclosed in some of the embodiments described below, and preferred features of this aspect are disclosed in other embodiments described below. Attached Figure Description

[0061] The following examples illustrate various aspects of the invention. It is to be understood that the invention is not limited to these examples. The scope of the invention is set forth in the appended claims.

[0062] In the embodiments, reference is made to the accompanying drawings, which are provided by way of illustration only and do not limit the scope of the invention. In the drawings: Figure 1 It represents the pressure in the cardiac artery and the area of ​​that artery; Figure 2 It shows how the area changes as a function of applied pressure; Figure 3 It records the pressure in the automatic oscilloscope cuff; Figure 4 The first step of an exemplary process using a measured PPG signal is shown; and Figure 5 This is a cross-section of the device according to the third aspect of the invention, while also showing a representation of the proximity signal. Detailed Implementation

[0063] Example 1: Calibration of PWV and PWA The limitation of all PWV and PWA technologies is that they must be calibrated for each individual user. This requires the user to take several blood pressure measurements using an occlusion (cuff) device while simultaneously measuring PWV or PWA. This allows for the calibration of the PWV or PWA, which is then used to detect changes in blood pressure measured with the cuff. Calibration typically remains valid for a period of days to weeks, after which it must be repeated. This limits the utility of PWV or PWA technologies because it also requires the availability of a cuff device.

[0064] Absolute blood pressure measurements using the cuffless occlusion method (either as a separate device as part of a kit or as part of an integrated device) can be used as a calibration for PWV or PWA measurements. Thus, PWV or PWA measurements can be used for quick and easy blood pressure measurements until recalibration is necessary.

[0065] The calibration procedure can be further strengthened by performing several calibrations under different conditions (e.g., at different times of day or before and after exercise). This distributed calibration can be used to improve the accuracy of subsequent PWV or PWA measurements or to extend the period before recalibration is necessary.

[0066] Example 2: Stability of Pulse Wave Analysis While PWA (Proof-of-Weight Measurement) is simple to perform, achieving sufficient accuracy is not easy. One reason is that the measured light wave depends on the pressure the user applies when pressing the measuring device onto the body part. A pressure sensor in the pressure device can be used in conjunction with its optical sensor to provide feedback to the user, instructing them to press harder or softer, thus generating a PWA waveform for a specific pressure. This can be used to ensure that the measured pressure is the same as the pressure used for calibration, or to provide a set of waveforms captured at different pressures for PWA analysis.

[0067] Alternatively, the actual measured applied pressure can be used as input to the PWA algorithm without providing feedback to the user, in order to improve its accuracy and / or extend the time before recalibration is required.

[0068] Example 3: Estimation of Pre-ejaculation Phase (PEP) The PTT determined using electrical signals includes the PEP, therefore the estimated PWV will be incorrect. The PEP is fairly stable for a person, so the measured PTT can be corrected with occasional measurements.

[0069] PCT 4, Figure 9, and the ninth aspect of PCT 4 show that the apparatus according to the Leman application can directly measure PEP. This measurement may be used to improve the accuracy of PWV estimation.

[0070] Example 4: Direct estimation of arterial stiffness PWV is related to blood pressure via arterial stiffness. If this stiffness is known, this relationship can be estimated more accurately, leading to a more accurate estimate of blood pressure derived from PWV. Since the waveform analyzed by PWV also depends on PWV, stiffness can also be used to improve the accuracy of PWV.

[0071] PCT 4, page 11, lines 9-14 discloses that local arterial stiffness can be directly measured by the Leman device.

[0072] Example 5: Direct estimation of surrounding tissue stiffness The effective stiffness of an artery also depends on the stiffness of its surrounding tissue. A fifth aspect of PCT 5 discloses a device according to the Leman application that can estimate the stiffness of this tissue, including changes due to hydration. This can also be used to improve the accuracy of PWV and PWA measurements in a manner similar to the fourth embodiment described above.

[0073] Example 6: Improving Cuffless Closure Technology Using PWV Data PCT 2, lines 24-30, discloses that cuffless occlusion devices can use estimates of arterial stiffness to improve some techniques for extracting blood pressure from occlusion data. While it's assumed that the estimate is derived directly from the measured data, there are advantages to using independent estimates (i.e., those derived from PWV or PWA measurements). This benefits both the accuracy of the results and the speed of processing.

[0074] LMD applications disclose several techniques for extracting blood pressure from data derived from sensors using search or optimization algorithms. These techniques operate by searching a solution space, including searching for diastolic and systolic blood pressure. Estimates of these values ​​derived from PWV or PWA can be used to narrow down the search space, or at least to indicate the starting values ​​for the search. This reduces the time spent searching and lowers the risk of the search selecting suboptimal solution values.

[0075] Example 7: Isobar Correction refer to Figure 1 The dashed line illustrates that the typical lumen area of ​​an artery is a function of the difference between the instantaneous pressure of arterial blood and the instantaneous pressure of the tissues surrounding the artery. The vertical dotted line shows the pressure difference during systole (when arterial pressure is at its maximum and the difference is at its minimum) and diastole (when arterial pressure is at its minimum and the difference is at its maximum). The double-ended arrow labeled deltaA shows the area change between systole and diastole.

[0076] Notice Figure 1 The exact shape and vertical proportions will depend on the size and stiffness of the artery, the stiffness of the surrounding tissues, and the characteristics of the measurement method.

[0077] Clearly, the value of deltaA depends on the pressure of the tissue surrounding the artery. Figure 2 This is a typical graph of deltaA as a function of tissue pressure around the artery (labeled "applied pressure"). Figure 2 Typical values ​​for diastolic blood pressure (DBP) and systolic blood pressure (SBP) are marked on the label.

[0078] Through Figure 2 Plot deltaA in the graph, and normalize it to the maximum value of deltaA in the graph if necessary. Figure 1 The vertical proportion is no longer meaningful.

[0079] This is a well-established technology for measuring blood pressure, where the pressure in the peripheral tissues does not change significantly during a single heartbeat. Figure 3 This is illustrated. This is a pressure record from the cuff of a conventional automated oscillometric blood pressure monitor. The pressure change per heartbeat is at most 2.5 mmHg, a clinically acceptable level of uncertainty. However, if these changes were much larger, whether random or systematic, it would be impossible to make a reasonable estimate of the pressure in the tissues surrounding the arteries. The pressure during systole is incorrect for diastole, and the pressure during diastole is incorrect for systole; an average pressure that is incorrect for both is meaningless because... Figure 1 It is non-linear.

[0080] This aspect of the invention does not directly use deltaA. Instead, it uses the following sequence of steps: 1. Extract A from the data DBP The estimate (i.e., the lumen area of ​​the artery during diastole at each heartbeat) is obtained, and the instantaneously applied pressure is measured simultaneously (assuming it is the same as the pressure around the artery). 2. Draw A DBP A graph of the function for instantaneously applied pressure; 3. By representing A DBP A smooth curve is fitted to the point of instantaneously applied pressure, thus giving A. DBP Parametric model of instantaneously applied pressure; 4. Regarding A SBP With instantaneous application of pressure, repeat steps 1 to 3; and 5. Create a set of "pseudo-heartbeats", where deltaA is obtained by using A from its parametric model. DBP The value minus the A given by its parameter model SBP The values ​​are estimated by means of the same instantaneous applied pressure (the term "isobaric" reflects this same instantaneous pressure).

[0081] This set of pseudo-heartbeats can then be analyzed using any analytical method used for actual heartbeats, provided there is known instantaneous applied pressure.

[0082] Smooth curves can be found using curve fitting techniques well-known to those skilled in the art (such as the Loess algorithm). In addition to providing a parameterized model, the parameters of the curve fitting technique can be selected to smooth the data, thereby reducing the impact of measurement noise.

[0083] If the instantaneous pressure of the tissue surrounding the artery lies between the diastolic and systolic blood pressures, the luminal area of ​​the artery will rapidly increase when the instantaneous arterial pressure exceeds the instantaneous pressure of the tissue surrounding the artery. It will also rapidly decrease when the instantaneous arterial pressure drops below the instantaneous pressure of the tissue surrounding the artery. The timing of these two events during a heartbeat can also be used to estimate diastolic and systolic blood pressure in a manner similar to deltaA. For example, in a noise-free ideal model, the interval between these two times is zero if the instantaneous pressure of the tissue surrounding the artery is equal to or greater than the systolic pressure. Similarly, if the instantaneous pressure of the tissue surrounding the artery is equal to or less than the diastolic pressure, the interval is equal to the duration T of the heartbeat. H .

[0084] Some techniques used to determine diastolic and systolic blood pressure utilize this interval. They can compensate for the effects of different applied pressures using the same techniques used for deltaA, where the equivalent steps are: 1. Extract T from the data R The estimate (i.e., the time it takes for the lumen area of ​​the artery to rapidly increase with each heartbeat) is obtained, and the instantaneously applied pressure is measured simultaneously (assuming it is the same as the pressure around the artery). 2. Draw T R A graph of the function for instantaneously applied pressure; 3. By representing T R A smooth curve is fitted to the point of instantaneously applied pressure, thus giving T. R Parametric model of instantaneously applied pressure.

[0085] 4. Regarding T F (i.e., the time it takes for the lumen area of ​​the artery to decrease rapidly with each heartbeat) and instantaneously apply pressure, repeating steps 1 to 3; and 5. Create a set of "pseudo-heartbeats", where deltaT is obtained by using T from its parametric model. F The value minus the T given by its parameter model R The values ​​were estimated using the same instantaneous applied pressure.

[0086] This set of spurious heartbeats can then be analyzed using any analytical method used for real heartbeats, provided there is a known instantaneous applied pressure. It will be apparent to those skilled in the art that T... F T Rand T H Other combinations, such as (T) F -T R ) / T H .

[0087] Example 8 - Blood viscosity Figure 4 The first step of an exemplary process using the measured PPG signal as a function of pressure is shown, in this case, as green light. Only the low-frequency signal is shown. High-frequency fluctuations caused by the lumen area of ​​the artery are too small to be seen in this graph.

[0088] Figure 4 It also demonstrates how to effectively model the signal by incorporating the pressure signal as input into the model: Terms related to the pressure integral; Items related to systolic blood pressure: if the blood pressure exceeds the systolic blood pressure, the artery will become blocked; Linear variations in sensitivity due to tissue deformation; and Sub-items related to instantaneous pressure and rate of change of pressure.

[0089] Similar results can be obtained for other colors of PPG light (including but not limited to red and infrared light) and for high-frequency PPG signals.

[0090] The model parameters are used as input to machine learning to find the combination of parameters that best predicts blood viscosity.

[0091] Example 9 - Proximity Detection Figure 5 A cross-section of the LMD device and a representation of the proximity signals are shown. These signals can be analyzed by signal processing techniques to estimate the distance to the surface. This distance can be used to provide feedback to the user, guiding them to position the device at the correct distance. Alternatively, the estimated distance can be used to correct for errors caused by any measured distance when no body part is touched.

[0092] It should be clearly understood that, for all aspects of the invention, the embodiments and figures and their descriptions are provided purely by way of illustration, and the scope of the invention is not limited to such description of specific embodiments; the scope of the invention is set forth in the appended claims.

Claims

1. A kit comprising an occlusion device, a pulse wave velocity (PWV) device, and an analysis means for analyzing signals generated by the occlusion device and the pulse wave velocity device, the occlusion device, the pulse wave velocity device, and the analysis means being adapted to work synergistically, wherein: The occlusion device is used for non-invasive measurement of a subject's blood pressure and for calibrating the pulse wave velocity device, and includes: An area method used to measure changes in the lumen area of ​​the arteries of the subject during heartbeat; A contact means for contacting a body part of the subject containing the artery, and for applying pressure to the body part by pressing the contact means onto the body part or pressing the body part onto the contact means; and A pressure device for measuring the instantaneous pressure between the body part containing the artery and the contact device; The pulse wave velocity device includes: A measuring means used to perform a measurement from which pulse wave velocity can be obtained; The analytical method described is suitable for: The subject's blood pressure is determined by analyzing measurements of the instantaneous pressure applied to the contact means and changes in the lumen area, and an improved estimate of blood pressure derived from pulse wave velocity is obtained from the measurements performed by the measuring means and the determined blood pressure. Use curve fitting algorithms to create two parametric curves representing the values ​​during diastole and systole; A set of pseudo-heartbeats is created using the difference between the two parametric curves, these pseudo-heartbeats having the same instantaneous pressure applied to the body part during both diastole and systole; and If the instantaneous pressure applied to the body part does not change significantly during the heartbeat, the set of spurious heartbeats is analyzed in the same manner as real heartbeats.

2. The kit according to claim 1, wherein, The analytical method is also suitable for: An estimate of the pulse wave velocity is obtained from the measurement performed by the measuring means of the pulse wave velocity device; An estimate of the subject's blood pressure is derived from the estimate of the pulse wave velocity; and Using the estimate of the subject's blood pressure derived from the estimate of the pulse wave velocity, to: Improve the accuracy of the determined blood pressure; To expedite the processing of measurements of instantaneous pressure and luminal area changes in order to determine blood pressure; or Improve the search strategy for the optimization technique used in determining blood pressure.

3. The kit according to claim 1, wherein, The measurement method uses an electrical sensor to detect the electrical triggering of the heartbeat.

4. The kit according to claim 1, which is adapted to provide estimates of systolic and diastolic blood pressure.

5. The kit of claim 1, further comprising means for instructing the user to adjust the force of the device pressing on the body part or the force of the body part pressing on the device.

6. The kit according to claim 1, wherein, The analytical method is suitable for estimating arterial stiffness and using this estimation to improve the accuracy of blood pressure estimation or the convenience of analyzing the pulse wave velocity.

7. The kit according to claim 1, wherein, The analytical method is suitable for estimating the stiffness of the tissue surrounding the artery and using this estimation to improve the accuracy of blood pressure estimation or the convenience of analyzing the pulse wave velocity.

8. The kit of claim 7, wherein the estimation of the stiffness of the tissue surrounding the artery includes an estimation of the hydration state of the tissue.

9. The kit according to claim 1, wherein, The analytical method described is suitable for estimating the pre-ejaculation phase.

10. An integrated device comprising: Area measurement, which measures changes in the luminal area of ​​arteries during a subject's heartbeat; A contact means for contacting the subject's body part containing the artery and for applying pressure to the body part by pressing the contact means onto the body part or pressing the body part onto the contact means; A pressure device for measuring the instantaneous pressure between the body part containing the artery and the contact device; A measuring means for measuring pulse wave velocity (PWV) using a pulse wave velocity (PWV) device, from which the pulse wave velocity can be derived; and An analytical method suitable for determining the subject's blood pressure by analyzing measurements of instantaneous pressure applied to the contact means and changes in lumen area, and for deriving an improved estimate of blood pressure derived from pulse wave velocity from the measurements performed by the measuring means and the determined blood pressure: Use curve fitting algorithms to create two parametric curves representing the values ​​during diastole and systole; A set of pseudo-heartbeats is created using the difference between the two parametric curves, which have the same instantaneous pressure applied to the body part during diastole and systole. and If the instantaneous pressure applied to the body part does not change significantly during the heartbeat, the set of spurious heartbeats is analyzed in the same manner as real heartbeats. The area means, contact means, and pressure means are used to calibrate the measurement means.

11. The integrated device according to claim 10, wherein, The analytical method is also suitable for: An estimate of the pulse wave velocity is obtained from the measurement performed by the measuring means of the pulse wave velocity device; The estimated blood pressure of the subject is derived from the estimated pulse wave velocity; Using the estimate of the subject's blood pressure derived from the estimate of the pulse wave velocity, to: Improve the accuracy of the determined blood pressure; To expedite the processing of measurements of instantaneous pressure and luminal area changes in order to determine blood pressure; or Improve the search strategy for the optimization technique used in determining blood pressure.

12. The integrated device according to claim 10, wherein, The measurement method uses an electrical sensor to detect the electrical triggering of the heartbeat.

13. The integrated device according to claim 10, which is adapted to provide estimates of systolic and diastolic blood pressure.

14. The integrated device of claim 10, further comprising means for instructing a user to adjust the force of the device pressing on the body part or the force of the body part pressing on the device.

15. The integrated device according to claim 10, wherein, The analytical method is suitable for estimating arterial stiffness and using this estimation to improve the accuracy of blood pressure estimation or the convenience of analyzing the pulse wave velocity.

16. The integrated device according to claim 10, wherein, The analytical method is suitable for estimating the stiffness of the tissue surrounding the artery and using this estimation to improve the accuracy of blood pressure estimation or the convenience of analyzing the pulse wave velocity.

17. The integrated device according to claim 16, wherein, The estimation of the stiffness of the tissue surrounding the artery includes an estimation of the hydration state of the tissue.

18. The integrated device according to claim 10, wherein, The analytical method described is suitable for estimating the pre-ejaculation phase.

19. A kit comprising an occlusion device, a pulse wave analysis (PWA) device, and an analysis means for analyzing signals generated by the occlusion device and the pulse wave analysis device, the occlusion device, the pulse wave analysis device, and the analysis means being adapted to work in concert, wherein: The occlusion device is used for non-invasive measurement of a subject's blood pressure and for calibrating a pulse wave velocity device, and includes: An area method used to measure changes in the lumen area of ​​the arteries of the subject during heartbeat; A contact means for contacting a body part of the subject containing the artery, and for applying pressure to the body part by pressing the contact means onto the body part or pressing the body part onto the contact means; and A pressure device for measuring the instantaneous pressure between the body part containing the artery and the contact device; The pulse wave analysis device includes: A measurement method used to perform a measurement from which an estimate of blood pressure can be derived using pulse wave analysis; The analytical method described is suitable for: The subject's blood pressure is determined by analyzing measurements of the instantaneous pressure applied to the contact means and changes in the lumen area, and an improved estimate of blood pressure is derived from the measurements and determined blood pressure using pulse wave analysis. Use curve fitting algorithms to create two parametric curves representing the values ​​during diastole and systole; A set of pseudo-heartbeats is created using the difference between the two parametric curves, these pseudo-heartbeats having the same instantaneous pressure applied to the body part during both diastole and systole; and If the instantaneous pressure applied to the body part does not change significantly during the heartbeat, the set of spurious heartbeats is analyzed in the same manner as real heartbeats.

20. An integrated device comprising: Area measurement, which measures changes in the luminal area of ​​arteries during a subject's heartbeat; A contact means for contacting the subject's body part containing the artery and for applying pressure to the body part by pressing the contact means onto the body part or pressing the body part onto the contact means; A pressure device for measuring the instantaneous pressure between the body part containing the artery and the contact device; A measurement method for using a pulse wave analysis device to measure blood pressure, from which an estimate of blood pressure can be derived using pulse wave analysis; and An analytical method suitable for determining the subject's blood pressure by analyzing measurements of instantaneous pressure applied to the contact means and changes in lumen area, and for deriving an improved estimate of blood pressure from the measurements and determined blood pressure using pulse wave analysis: Use curve fitting algorithms to create two parametric curves representing the values ​​during diastole and systole; A set of pseudo-heartbeats is created using the difference between the two parametric curves, which have the same instantaneous pressure applied to the body part during diastole and systole. and If the instantaneous pressure applied to the body part does not change significantly during the heartbeat, the set of spurious heartbeats is analyzed in the same manner as real heartbeats. The area means, contact means, and pressure means are used to calibrate the measurement means.

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