JPS60501740A - Method and device for diagnosis of coronary artery disease - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] BACKGROUND OF THE INVENTION Method and device for diagnosis of coronary artery disease A number of devices are known for obtaining blood pressure measurements. There are intrusive (1nvaslv@) devices and non-intrusive (nontnvastv@) devices. ) includes both devices. Sea Nis Liver (C0S, Weavsr) ), J.S. Eekerlsy, P.M. ・Neugard (P, M, Neugard), C.T. Warnk (C, T .

Warnka), G.B., Angel (J, B, Angell), Ni Terry (S, C, Terry) and Robinson (J, Ro) “Research on non-invasive blood pressure measurement technology (A5 study of Non-1nvaslve Blood PrsssureMeagvrem ant Technlqves) Essay entitled ((O(\te, many A non-invasive measurement device is disclosed, the paper published at Stafford University, July 7th, 2013. It was submitted at a conference held at 5ociety of Photo-Optlcal Instrument III viscerovascular disease, @ (cardiovascular dlseasa) diagnosis Measurement of visceral systolic (aystollc) and cardiac diastolic (diaatollc) blood pressure Similar to the value, ! pulse rate and rhythm ) has long been known to be used. Furthermore, an electrocardiograph (elea) Trocardiography (ECG) measurement can diagnose heart disease5@ It is well known that -21 product with the above important thing “it 60-501740 (3) There is. However, today, before the activity, during the activity, and after the activity (person) (5u bjec, t) arterial blood pressure wave (arterial blood pres++ Measurement of contraction slope (aystollc5lope) of urs wave) The use of constant values at the same time as comparison with such measurements obtained from healthy individuals The value is coronary artery disease, @(eoronary art@ry disease :CAD) is not recognized in the diagnosis.

Purpose and outline of the present invention The object of the present invention is to provide an improved method for diagnosing coronary artery disease. and provision of equipment.

The object of the invention is to provide an improved diagnostic method and device of the type described above, It is the subject's heart contract during the range of activity. llity).

The above-mentioned and other objects and advantages of this invention are achieved by the activities carried out by the subject (person). Subject during pre-, active- and post-active cardiac contractions (s+ystole) The time rate of change in the pressure inside the artery of the subject (i.e. the blood pressure in the subject's artery) It is obtained by periodically taking measurements of the wave contraction slope. activity proto These at different times during the col (ex@rcise protocol) The actual value of the measured value of , as well as the constant change in that measured value during the activity protocol, From people who have been diagnosed with CAD in subjects and who do not have known CAD. It is compared with the corresponding measurement value obtained.

The seven devices used to obtain periodic measurements of the systolic slope of arterial blood pressure waves are inflatable. including the use of a cuff capable of inflating the cuff to a pressure above the cardiac systolic pressure. It is possible to contract to a pressure below the cardiac relaxation pressure. pressure transgy - the inflatable cuff is connected to the inflatable cuff for generating a signal, the signal being connected to the cuff pressure (eu ffpressure). The microphone is connected during cuff deflation. Detect the Rotkov sound (Korotkov 5ound) and target ( Electrodes attached to the patient) pick up electrocardiograph signals. K-Sound (K -++ound) detector detects the Korotkoff sound from the microphone, And the R-wave peak (R-wave peak) detector detects the peak of the ECG R-wave. Detect. The first sound signal and R wave signal from the detector are generated by a computer. The pressure transducer output is converted into a signal for use by the computer. converted to digital form for transmission to a computer and storage in computer memory. . The R-wave signal and the sound signal are recorded in the converter memory as such. Interrupt signal (lnt@rrupt slgnal) ) to the computer. Optionally, ECG and/or Korotkoff The sound waveform can be digitized and stored in the converter memory. R-waves and/or - along with the arrival time of the software that detected the sound. Software R-wave and/or in the computer - input to the sound detector . The arrival time of the R-wave signal and the relative arrival time of the sound signal during cuff deflation. The time interval (time 1ninterval) between and the resulting RK interval (RK int rv ai) and the associated cuff pressure are stored in computer memory. RK in Turno (le is the real Korotkov sound and the artifact) processed to distinguish between. Minimum mean variance fitting technique - squared fittlngtechnique) MlfJ to the true RK interval vs. cuff pressure point set by the data. The straight line has a slope inversely proportional to the systolic slope of the arterial blood pressure wave. Ru. During a sequence of activities, multiple such l'-RK slopes (RK-5lope ) J measurement value is obtained. These measurements obtained during the activity protocol, and and changes in these measured values for the diagnosis of coronary artery disease (CAD) in the subject. , compared with corresponding measurements obtained from healthy subjects and changes therein. It will be done.

Brief description of the drawing The invention will be better understood from the following description when considered in conjunction with the attached drawings. Dew. In the drawings, like reference symbols refer to the same parts in different figures. : Figure 1 shows the electrocardiograph signal and RK interval! is a plot of the associated arterial blood pressure wave; the RK interval measurement is 3 Used in the system shown in Figure; Figures 2A and 2B show subjects without coronary artery disease and subjects with coronary artery disease. arterial blood pressure waves at different times during successive activities for each of the participants). A graphical illustration is shown for each; FIG. 3 shows that the measured value of the contraction slope of the blood pressure wave is acquired periodically, and the measured value is 1 is a simplified block diagram of a system for displaying the system; The system embodies the invention; FIG. The RK interval as a function of cuff pressure is used in explaining the operation of the The tA-T curve is a plot of patients with no known history of coronary artery disease. Slope measurements for subject vL vs. heart beat rate (heart bs+) This is a graph of ``atrate　). Part 3-A-, regarding the subject (person) for whom the matter was known! rD shown in the diagram It is a graph similar to; Figure 7 is a frame for use in explaining the operation of the system shown in Figure 3. It is a low chart; Figure G is 5 subjects with and without coronary artery disease. shows a graph of "rRK-slope" measurements versus time for a subject; and Figure 2 shows details of the steps in the flowchart of Figure 7; , Shrinkage slope measurement for use in identifying subjects (persons) with CAD. Fixed value various parameters are used by the conbeater.

First, referring to FIG. 1, in FIG. rdigraph signal) / q and related branches, branch artery pressure waves (brachlal artery pressur@whve)/2 part is It is shown. In accordance with the invention, the (heart) of the pressure wave periodic measurements of the contraction slope (ay+tolicI Blope) It is done during an exercise routine. Slope measurement is generated during the course of an activity protocol. A constant change in the slope of the slope, along with a constant value, is used to determine what is known about the diagnosis of the disease. Coronary artery disease (CAD) Other subjects (persons) with e) and those without the disease It is expressed numerically based on corresponding measurements obtained from other subjects. Collection Various methods for obtaining measurements of contraction slope are known in the art. These include those described in the aforementioned Weber et al.

The apparatus of the present invention employs seven of the slope measurement methods disclosed in said paper. , shown in FIG. 3 and described below. However, firstly, CAD The contraction slope of a subject (person) without CAD and the contraction slope of a subject (person) with CAD 2A and 2B, along with some differences that are useful in the diagnosis of CAD. Each will be described in the figure. The contraction slot illustrated in Figure 2B. A group represents many, but not all, types of CAD. and is shown for illustrative purposes only.

Before, during, and after activity stress (exvrcise mtresa) The contraction slope portion of the resulting pressure wave is illustrated in Figures 2A and 2B. It is. For descriptive purposes, the subscripts A and A in Figures ZA and 2B The same reference symbols, except for the use of B, refer to the same relative time during the activity protocol (r@1 Regarding the pressure pulses obtained in the active timings, Figure 2A and and Figures 2B and 2B, respectively. Before the activity and during the hiatus, ( The pressure) waves are identified by the reference symbols 2OA and 20B. These (pressure) Both waves represent (cardiac) systolic and (cardiac) diastolic pressures, where systolic and diastolic pressures are Things that should be within their normal range are taken into account.

However, the contraction slope of the pressure wave is different between 2OA and 20B, and the pressure wave The contraction slope of force wave 2OA is the contraction slope of pressure wave 20B! larger than typical In particular, contraction slots for subjects (persons) with CAD that are at rest prior to activity. The contraction slope is smaller than the contraction slope for subjects without CAD.

2.2A-2 and 22-3 are each 2 minutes after the activity.

Typical pressure waves observed after ≠ minutes and 6 minutes. No CAD involved For subjects, the contraction slope increases slowly with increasing activity. will be understood. Although not shown in Figure 2A, increased activity The contraction slope usually increases to a maximum value with increasing activity, and then decreases during continuous activity. The contraction slope remains substantially at said maximum value.

As seen in Figure 2B, during the activity for the subject (person) with CAD. Pressure wave expressed, 2≠B−/.

21, IB-, 2 and 2! B~3 shows the increase in contraction slope with activity , followed by a contraction slope that decreases with further activity. Left ventricle (1e When the ft ventricle contracts, all the blood is released from it It's not. Typically, only 50% is released when the subject is in a dormant state. Not served. The release percentage, 100 parts, is the release rate (EF: 5jeet lon fraction). EF involves injecting a radioactive solution into the bloodstream. Then, a radionuclide camera (radl The left ventricle is photographed using an onuclide camera. aphing).

These photos show the left side to be determined at multiple points during the heartbeat. Allowing for the size of the ventricles, a determined value of EF can then be calculated. except for dangerous techniques Ta As a result, X-ray dye is injected directly into the coronary artery. , EF measurements during activity have previously provided the most accurate known CAD indicators. Ta. Typically, a healthy subject's □EF will gradually increase during activity. However, on the other hand, the EF of subjects with CAD initially increases, but then Decrease. This decrease is generally due to a decrease in cardiac contractility. It is believed. Low cardiac contractility reduces the contraction slowness of pressure pulses in branch arteries decreases the Simultaneously occurring radioisotope E F (radio-1@ otopeEF) and contraction slope measured in subjects with CAD and those with CAD. The upper limit between the EF and slope measurements is The interrelationships noted are observed.

There are differences between healthy subjects and subjects with CAD that change after activity. Other differences in the contraction slope and turns are often observed, and Illustrated in FIGS. 2A and 2B. Pressure wave, 2gA-/, 2gA -2 and 24tA-3 are typical in healthy subjects, Observations were made at 2 minutes, IIL minutes, and 6 minutes after activity, respectively.

Immediately after the activity, the contraction slope remains essentially the same as the slope just before the end of the activity. present, and then slowly decrease over time, returning to a dormant state before activity. reaching the slope of the state. This number turn has CAD multi-70 1 bale B anus 0-5 01740 (5) In contrast to the pattern observed in many subjects (persons) , in the pattern of subjects with CAD, the contraction slope is Often, before returning to the pre-activity slope, the pre-activity dormant slow decreases below the current level. The pressure wave at the time point 6 minutes after the activity in Figure 2B, 241B-3 has a contraction slope smaller than that of pressure wave 20B before activation. This indicates that there is a loop. As mentioned above, such a low contraction slope is Displays physical conditions related to cardiac contractility and low EF, and which are currently dangerous. manifest. Here, in the activity procedure for Figures 2A and 2B, the measured values are obtained at corresponding times, but different runs occur during the active part of the procedure. It must be noted that the movement can be consumed by the subject. No.j　A　 -j In Figure D and Figures A to ZD, the heart beat rate A plot of measured contraction slope as a function of rate) is shown. , using a physician with an indication of the amount of exercise exerted by each subject during the activity procedure. I mean it.

As mentioned above, the time derivative of blood pressure and the pressure during the systolic slope (t1m@-deriv Various devices are known for measuring the contraction slope. Provide rope measurements. blood pressure wave An apparatus embodying the present invention for obtaining measurements of the contraction slope of ) is shown in Figure 3. Please refer to Figure 3 here. illuminated. The illustrated device is an inflatable tube that wraps around a limb, such as the subject's upper arm. cuff 30 and connected to the cuff via a pressure controller 3≠ and a pressure source 32. . Cuff pressure is determined by pressure drain juicer 3. The analog output from the pressure transducer is a digital signal format. Connect to the input of the analog-to-digital converter≠O via amplifier 3g to convert be done. The digitized cuff pressure signal is passed through digital multiplexer 'l-2. and is connected to a computer 4t≠, and the combiner is equipped with a memory≠1ltA. , in which the cuff pressure signal obtained during cuff deflation is temporarily stored. and used to calculate the measurement of the contraction slope of the blood pressure wave during the cuff deflation. It will be done.

In the cuff 30 attached to the subject's upper arm, the cuff has a cardiac systolic pressure (5 ystolla pres@ure) or more. after that, At the same time as the cuff pressure decreases, the first Korotkov sound (Korotkovs) ound) appears in the cardiac systolic pressure, and the final Korotkoff sound appears in the cardiac relaxation pressure (dlatollcpr@m8ur@). Ma The icrophone is used at multiple cuff pressures between cardiac contraction and relaxation. Pick up the Rotkoff sound (K-sound). The microphone output is is amplified by an amplifier≠g, and the output of the amplifier is sent to a signal converter jO and Sound detector! supplied to l. The converter jO is simply one-stable m, ) (monostable multi vibrator: one-shot) and amplified from amplifier 1Itf. generates a pulse output in response to one sound output, and the pulse output Connected to plexer≠2. K-Sound Detector 2 is a real sound (t distinguish between true K-sound) and artifacts, and produces an output responsive to said real one sound, said output being sent to a multiplexer. connected to an address input consisting of In the presence of the output from the K sound detector In this case, the output from converter jO is sent to computer I via multiplexer 4L,2. Connected to the interrupt input of It≠ and outputs one sound timing signal (K-5ou nd ttmlng signal) and set one sound timing accordingly. The signal is connected to the RK interface along with an associated R-wave timing signal. (RK Intsrva!).

gcG electrode polarity 0CG Shingetsu (IECG) that was probed into the body of the subject (person) ignal) is picked up, and the ECG signal is amplified by an amplifier, And then converter O≠ and R-peak detector (R-peak detect r) 6 Supplied to Party B. Similar to the transducer jO, the transducer z4t is also pulse output in response to the R-wave component of the amplified ECG signal. generate force.

The pulse output from the converter tag is connected as an interrupt input to the compico tag≠ Therefore, it is connected to the multiplexer≠co. The R-beak detector detects the R-beak of the ECG signal. - detect waves, while detecting noise and other components such as P-wave components and T-wave components. Make an identification. R-Peak detector output is multiplexer≠2 as address input When an R wave is detected, the output from converter 6 is sent to converter 4L. Connect to the interrupt input of ≠.

A sound associated with the arrival of the R-wave input at the interrupt input to the comviator The difference in time between the arrival of the signal provides a measurement of the RK interval and The interval is temporarily stored in the computer memory Hiro≠A, and the interval is along with other such RK interval values obtained in the subject's arterial blood Used to calculate values related to the contraction slope of pressure waves.

The other address inputs of the multiplexer≠2 are connected from the combinator≠≠. control unit 70. Under the control of unit 70 The multiplexer 412 connects the A/D converter to the converter ≠≠. Switched for connection of cuff pressure signal. In addition, the multiplexer address input The force information is supplied to the combinator 4tlIL via the force control unit 70. , used by the computer in controlling the operation of the multiplexer.

The name of the subject (person) to be tested, matters related to the subject, and activities. Combinations, such as various points in an activity glot including the start and end of a A keyboard 72 may be provided for manual entry of information to the controller. Data display and the recording unit 7≠ records the contraction slow of the subject at different activity levels. Displays tap information.

It can be used for displaying and/or recording. As will become clear, R.K. Using interval and cuff pressure information, the Combita calculates cardiac systolic blood pressure and It can be programmed to calculate the diastolic blood pressure, and the value of the blood pressure is further added to unit 7≠ can be displayed and/or recorded. Measurement of cardiac systolic and diastolic blood pressure Regarding the type of system shown in Figure 3, the system is ” in the above-mentioned essay by Leiber et al. The disclosure is expressly incorporated herein by reference. However, the said In , the relationship between contraction slope and CAD as a function of activity stress is CAD using measurement of contraction slope and changes in slope, not disclosed. A diagnostic device is also not disclosed in the discussion.

Referring briefly to FIG. 1 again, it shows that the systolic slope of blood pressure wave 7.2 and the RK The relationship between the intervals is shown. RK interval, i.e. R wave peak The time interval between the occurrence of the sound and the associated sound is related to the cardiac systolic pressure. It is the highest at cardiac relaxation pressure and the lowest at cardiac relaxation pressure. Cuff pressure is cardiac systolic pressure As the force is reduced, the RK interval is similarly reduced. well known As shown, the K sound is at its maximum magnitude midway between the upper and lower ends of the contraction slope. It gradually decreases to zero during cardiac contraction and relaxation.

During cuff deflation, multiple RK interval values are obtained and as a function of cuff pressure. A plot of such measurements is shown in Figure 7, which is referred to below. illuminated. In FIG. 7, the straight line 0 represents the minimum unbiased variance error fitting technique (min imum mean-squared error fitting technique iques) is used to traverse a series of points, and is shown adapted. The adaptation technique is easily implemented through the use of a combeater. The slope of the straight line, Δ The RK interval/Δpressure corresponds to the contraction slope of the blood pressure wave as shown in Figure 7. is inversely proportional and therefore provides a measurement of the systolic slope of the blood pressure wave. Akira Obviously, as the contraction slope increases, the slope of line IO decreases, and The same applies to the opposite case. In the above discussion of Leiber et al., the slot of the straight line gO is is a program that cannot distinguish between real Korotkoff sounds and artifacts. It will be noted here that it is determined and utilized.

As seen in the figure, the maximum cuff pressure and -1 and minimum cuff pressure provide measurements of systolic and diastolic blood pressure, respectively. Ru.

To obtain a true measurement of the contraction slope, Leiber's Korotkoff sound and human It can be used in the present invention to distinguish between artificial and artificial results. cardiac systolic blood pressure and heart It is noted here that knowledge of visceral relaxing blood pressure is not required in the practice of this invention. It will be noticed. Therefore, in using the device of FIG. The loop can be set using only points near the center of line ♂O, and the Points near the ends of the line 0, where the sound becomes very weak, are not used.

Of course, if desired, the device can be used to measure systolic and diastolic blood pressure. position can be used and such blood pressure is displayed along with the cardiac relaxation slope measurement. recorded and/or recorded or stored. The invention is a real Korotkov sound and person It is not aimed at determining how to distinguish between such artificial results. The results are removed by suitable processing of the signal from the detector 5.2 and directly The point in the plot of Figure 7 to which line 0 is fitted is the true Korotkoffsau. It is understood that the Probably.

As shown in Figure 7, a series of points are obtained for each cuff deflation, and A straight line 0 is fitted through the point. Such a straight slope is a combination. easily calculated by data. R-Peak wave generation/7 Using time, the time interval between adjacent R-peak waves is determined, and Its reciprocal is calculated to determine the heart rate during cuff deflation. Measurements are provided. During an activity cycle, or protocol, the above operations are repeated. is returned, thereby allowing multiple slots to be measured as a function of heartbeat measurements or as a function of time. The numerical values of the may be displayed and/or recorded.

In this application, the RK interval vs. cuff pressure slope (e.g., the line in Fig. The slope of the curve 0) is displayed as the RK slope for convenience.

Next, referring to Figure J''A-3D and Figures 1.h to 1.o, The types of records that can be provided by the system are shown. In particular, each color The slope of the straight line (i.e. R K-slope) is plotted as a function of heart velocity. Figures A-jB The data for these plots are based on healthy individuals with no known CAD. On the other hand, the data for the plot of No. 2 A-Otori diagram is obtained from the subject (person). are doing. The symbol “×” indicates the information obtained for the subject (person) at the time of inactivity before the activity. Tap the point. Points earned during the activity are identified by the symbol "mouth" and the points obtained after the activity are identified by the symbol "○". plot The points for this are 7g per 2 minute interval. 0(7) and the interval is computer 4L≠niprogrammed or can be inserted through the key-go door 2. Virtually continuous measurements are made 2 minute interval between measurements. things will be understood. The clock 4L4'B shown in FIG. provided to provide time measurements .

From Fig. The RK interval/cuff press-fitting slope (RK slope) is approximately 7. It is noteworthy that it is within the evening range. As seen in Figures Otsu A to Otsu C, For subjects with known CAD, the resting slope is approximately equal to 2. More than 2. Since the contraction slope is inversely related to the illustrated slope, The resting slope for a subject with a known CAD is approximately equal to or It will be understood that 05 or less. However, in the 6th figure, , a subject with CAD has been shown to have a normal starting slope of about /. It is.

During the activity, the RK slope for a healthy subject is shown in Figure 3A-J-D. As such, it decreases substantially exponentially to a value slightly above zero. RK slot This means that the systolic slope is inversely proportional to the systolic slope of the blood pressure wave. f: Indicates that the amount will increase to near the current level. Plot of RK slope shown in Figure 5 Power/Ri The characteristics of the waveform during activity are not typical of a healthy subject. .

Regarding the CAD target (person), as shown in Figures No. B A, B and ZC, the RK scale is Rope also generally decreases during activity, but is more accessible to healthy subjects. It never reaches a level as low as it is reached. Figure to In the seven CAD case illustrated in There is virtually no change in the observed slowness in healthy subjects. This is very different from the changes in the group.

After the activity, as shown in Figures A-jD, the RK scale for healthy subjects The rope slowly returns to the pre-activity level while the upper limit reached during the activity It remains roughly within the range of the upper and lower limits. Most subjects (persons) with CAD (Figure B A-4c), the slope rises rapidly during the post-activity period. Shiba As can be seen in diagrams No. Otsu A-Otsu B, the slope after the activity is the same as the slope before the activity. This means that the contraction slope of the bifurcation artery 9 Lus is similar to the release rate EF. means low. As mentioned above, the seven CADs illustrated in Figure 6 In the case of , the slope after the activity does not change much.

The system shown in Figure 3 was used to obtain measurements of the contraction slope during the active cycle. Although it is believed that the operation of the stem is clear, the flowchart in FIG. A detailed description of the operation of the system referred to will now be presented. Therefore The various operations noted are under the control of the computer and memory The program contained within IILVA responds to certain instructions. Obviously, seven or more programmed steps are the actual explanation of the displayed operation. It can be included in the physical design (implementation). displayed It takes the average programmer to program such steps for controlled operation. Listing the complete program is not required, as it is well within the skill of the art to do so. and are not included herein.

Accompanied by a cuff 30 properly secured to the subject (person) and transgisa Hirotsu and Otsu 0. , the test is started as indicated by the start step 100, and the test is started as indicated by the start step 100, At times, the system power source is turned on by a device not shown. n) or a reset operation is performed. Initial setting step ization 5 steps) 10 pieces are computer 4t4 inside counter, record This includes initial settings such as registers. Target (person) such as name of target (person) information is inserted via the keyboard 7.2 in step 10II-. It can be done. After the target is inserted by keyboard, proceed to step 10B. exercise stage, or exercise cycle The file part begins. For example, the word “pre-activity” is inserted at the beginning of the test. can be entered.

Treadmill (treadmll), fixed bicycle (5tationa) cuff inflation step 10 for the subject (person) on the ry blcycle) etc. t begins, and in the inflation step, the cuff is inserted under computer control. Through the operation of pressure controller 3≠, the cuff is inflated to a pressure above the cardiac systolic blood pressure. The blood flow in the branch artery is occluded. Next, step In step/10, the true Korotkoff sound or the artificial sound The cuff pressure is reduced to the first detected pressure, which is the true Korotkoff pressure. As for the sound, it is systolic blood pressure. At this point, Stella f//, As shown by 2, transducer 3g, amplifier 3g, transducer≠0 and cuff pressure is stored in computer memory through the use of digital multiplexers ≠≠ Can be placed within A.

Next, in step //l/L, the R peak wave is detected and its arrival time is stored in computer memory.

The arrival time of the associated Korotkoff sound is further stored in computer memory. It will be done. As mentioned above, in addition to detecting true Korotkoff sounds, K-sound detection The output device 32 may further be responsive to artifacts, in which case upon arrival of such artifacts. The time periods are also stored in computer memory. Any given R peak wave Also, the true arrival time of a sound and one or more artifacts The arrival time of the result can be stored.

In Step/B, the RK interval is calculated and the RK interval is The seven or more values of the file are stored with associated cuff pressure (step //f ). In step 7.20, the cuff pressure is then set to, e.g. is reduced by the amount of The next yc decision is from the K-sound detector. Executes determining whether an output is occurring. If not, the cuff It is known that the pressure decreased to below the relaxation pressure. If the decision is positive, i.e. If one sound is still detected, step //2 is started again and there together with the new RK interval value to which the newly decreased cuff pressure value relates. is memorized. If the cuff pressure is decreased below the relaxation pressure, the In this case, the sound is no longer detected, decision step 7.22 is negative, and A step is started, in which the count of R peak waves is used. The heart (beat) rate is calculated.

Heart (beat) velocity is calculated for the period between the preceding cuff inflation and cuff deflation during which a series of RK intervals in downward cuff pressure are obtained. It will be done. Step 3: In step B, the true Korotkoff sound is distinguished from the artificial results. separated and the resulting artifacts are removed from further processes. Corotofusa In any system, including the present invention, where sounds are detected, K-sound detection is essential. Other sounds may also be detected by the output device, especially if the subject is active. , and such artifacts are detected when the contraction slope is In order to obtain measurements, the true Korotkoff sound should be excluded. above Similarly, a false algorithm distinguishes between real Korotkoff sounds and artifacts. is included in Leiber et al.'s discussion above.

Minimum unbiased variance algorithm The real Korotkoff sound, as displayed in step 72g, using A straight line is fitted to the RK interval obtained from Calculated in step /30. In step /32, step /30 The slope calculated at step/24L and the heart rate calculated at Using ) Plot of slope vs. heart velocity (5lope versus heart rate plot). Then the decision step/3≠ begins. At that point, a decision is made as to whether the test should continue or not. will be done. A keyboard switch (not shown) enters the computer≠≠ manually. (manual entry). If the decision is If you decide to continue the strike, step 10B starts again and the point At the step, the operator or physician initiates the next step in the activity cycle, such as ``Activity.'' I can meet you. The subject then begins or continues the next stage of the activity cycle. Then, other measurements of contraction slope are taken and added to the plot.

If the test is finished, step/3B can begin and at that point, Plot analysis was performed by a physician and a healthy subject was diagnosed with CAD. A determination is made whether the plot of and said plot are different. tests and examinations The cut ends at Stella 7°/, 7g. Certain steps in the flowchart are It may be noted here that it can be carried out in a wise order. Probably.

Plot of contraction slope (here RK interval/cuff pressure slope) versus cardiac velocity. B, G, time, activities, etc., or a large number of mails obtained from them. The parameter obtains a numerical value that indicates the condition of the subject's heart. It can be used for Appropriate parameters obtained from a plot of RK slope versus time The parameters include the following, some of which are mentioned above: X Before the activity, RK Slozo during the hiatus, 2 During the period after the TA following the start of the activity The speed at which RK slowo decreases, , 2J- 3. Slope of the plot of RK slope versus time at the beginning of the activity, Increase in RK slope during the activity, increase in RK slope 2 minutes after the end of the activity Change in RK slope, B. Speed of change in RK slope 2 minutes after the end of the activity ,and Z Highest value of RK slope after activity.

Typical comparative values of parameters for people without CAD and people with CAD are The parameter numbers are given in the table below. Corresponds to the numbers in the list above.

Table I - Typical parameter comparison values ≠ No increase Slight increase ! Decrease Increase RK slope for subjects (persons) without CAD and subjects (persons) with CAD Reference is then made to Figures 1 and 2 showing graphs or plots of measurements versus time. The graph can be easily used as output from the combiner. Nozara Meter/and 3-7 are identified in the graph of the subject with CAD.

For those who do not bleed the CAD, the graph will be scanned during the first few minutes of the activity. It will be noted that the rope varies substantially exponentially. On the other hand, CAD The slope of the graph during the same initial period for the subject (person) with is essentially constant and then decreases rapidly. This decrease in slope The ratio is used in the numerical evaluation of Crameter 2.

7 of each? For parameters, a threshold value is set. can be set up from an examination of data from a large number of subjects. for example The threshold value for ,・crameter/,RK slope at rest before activity is CA Set between the mean for people with D and the mean for people without CAD be done. From the examinations in Figures 31 to JD for healthy subjects (persons) to the pre-activity The average resting RK interval is of the order of Z,2, with a known CAD. From Figures Otsu A to JD for the subject (person), the slope at rest is 2. evening This is the order. For example, tg can be used as a threshold value between these average values.

The threshold values for this and other parameters are stored in the converter memory. be remembered. For A' parameter /, the calculated RK slope at rest is the threshold / , f, and if the RK slope is smaller than the threshold value, there is no abnormality. It is considered that If, as a result of the comparison, the crameter is the threshold or force, the topoint) If it is greater than or equal to (cut paint), the value / is assigned to the corresponding 9 parameters. and if the parameter is lower than the threshold, then the value -/ is lower than the parameter. These outputs can be assigned to meters depending on the importance of the parameter in diagnosis. It is therefore weighted: with negative weighting if necessary. many kinds The weighted values for the parameters indicate the condition of the subject's coronary artery. may be appended to provide a total number. This number is consistent with the individual weighted numbers. can be read out from the computer together. Such a system requires a lot of information about CAD. It is well suited for screening a number of objects.

Parameter values can be obtained directly from the RK slope vs. time plot or graph. , and that manual calculations can be used in the evaluation. Will. Optionally, the combiner is well adapted to perform such calculations. Ru. In the diagram referred to next, the trajectory obtained during the activity procedure of the subject (person) Chart block/31. Details are shown. Step/31. − Parameters /-7 are determined and/or evaluated in /3-7, respectively. and weighted, and in step/3-g, the weighted values are summed. and the results are displayed.

2g Nonlinear discriminant function (nonlllnaar d) is not suitable for manual analysis. iscrimlnant function) is a combinator of measurement data. It may be noted here that further evaluation can be included in the algorithm. Dew.

Of course, the invention is not limited to the algorithmic process described above. for example , the parameters listed above can be weighted to display relative abnormalities in cardiac status. Ru. These equally weighted values can be summed, and the total is either no anomaly or no anomaly. Can be compared to cut-paints for state indications . Again, such an evaluation can be done manually, based on the data obtained during the activity procedure. , or by a conbeater.

In the above analysis, heart rate is used as a proxy for time. It can be done. All parameters except parameter 2 are assumed to use heart velocity. determined.

For use with plots that include heart velocity, the parameter values are the function 5(r) = Kf3-” is fitted to the data points of RK 5(r) is the slope of the function, and r is the slope of the function. (heart) velocity, and K is the other constant.

Although the invention has been described in detail in accordance with the requirements of patent law, various other changes and modifications may be made. and modifications will suggest to those skilled in the art. 2 as a function of cuff pressure Since the slope of the RK interval is a function of the contraction slope, the RK slope is converted to a systolic slope that can be plotted as a function of time, heart rate, etc. obtain. The other obvious change is that the cuff inflation and deflation is controlled by the Combiator control. This includes the use of a manually inflatable cuff rather than the illustrated example below. ◎Furthermore, as mentioned above and in the discussion of Leiber et al. Systolic and diastolic blood pressure measurements with true Korotkoff sound during cuff inflation Obtained from cuff pressure measurements taken when the first and last sound is heard. and these pressures may further be displayed and/or recorded. Up As described above, the operation of this device is to control cardiac systolic blood pressure, cardiac relaxation, and to provide the subject with An input may be provided to the combiator from an active device, etc. It is clear that the work performed by a subject (person) throughout the work cycle can be recorded. It will be.

Furthermore, devices other than interrupt inputs are responsible for the generation of R peak waves and Korotkoff sounds. It will become clear that it can be used to enter time into a computer.

Either versatile or dedicated combinators can be used. Additionally, the required input can be recorded, and the recording can be played back (to provide computer input). play-back). In addition, other blood pressure transducers and systems A system can be used to obtain contraction slope measurements from the transducer and system. If the system is known to contain an intrusion device, e.g. There will be. The above and other such changes and modifications may be included within the scope of the appended claims. It is intended to be included within the spirit and scope of the invention as defined.

Figure 2B Figure 3 Figure 4 Figure 8 I-Shikumaro-Defeating/Minute- Figure 6A Figure 6B Figure 7 Figure 9 international search report

Claims (1)

[Claims] /, In a method for detecting coronary artery disease in a subject, contraction of an arterial blood pressure wave of the subject obtaining a slope measurement; and As an indication of coronary artery disease within the subject, it was obtained from individuals without coronary artery disease. comprising using a difference in the slope measurement value from a slope measurement value. How to do it. Measurements are taken while the subject is at rest and are at rest in individuals without coronary artery disease. A small resting systolic slope is also an indication of coronary artery disease. The method described in Scope 1. 3. Substantially 0. ! r　w　Hg/ms and lower resting contraction slope 3. The method of claim 2, wherein is indicative of coronary artery disease. Long measurement values are obtained continuously while the subject is active, increase during the activity, and then Claim 1: The decreasing systolic slope is indicative of coronary artery disease within the subject. How to put it on. The measured values are continuous for the time period before and immediately after the end of the activity by the subject. The post-activity contraction slope, which is obtained by 2. The method of claim 1 for displaying coronary artery disease in a patient. B. Measurements are obtained continuously before, during, and at rest after the activity, and the coronal The pre-activity contraction slope of individuals without arterial disease is similar to the pre-activity contraction slope of individuals without arterial disease. contraction slope, which increases during activity and then decreases, and contraction before activity. The contraction slope during the post-activity rest is smaller than the slope of the coronal slope within the subject. A method according to claim 1 for indicating arterial disease. Z. Obtaining a measurement of heart velocity while a measurement of systolic slope is being obtained, and Measurement of systolic slope versus cardiac velocity to provide a record of systolic slope versus cardiac velocity 2. The method of claim 1, comprising: plotting. & Contraction slope vs. time obtained during the activity glotcol performed by the subject 2. The method of claim 1, comprising plotting the measured values. 2. In a method for detecting coronary artery disease in a subject, the comprising obtaining periodic measurements of the systolic slope of an arterial blood pressure wave, the activity cycle being Including a resting part before the activity, an active part, and a resting part after the activity, If the slope measurement is determined by individuals without coronary artery disease during similar activity cycles. Determine whether the slope measurements obtained from the body exhibit the characteristics of coronary artery disease. A method characterized in that the slope is displayed by a difference in characteristics in the slope measurement values. . 70 33 with transducer responsive to cuff pressure Inflatable cuff, deflated using R-liquid detection device and Korotkoff sound detection device Periodic measurements of the slope are obtained non-intrusively and the transducer and detection device Blood pressure, R-wave signal and Korotkoff sound signal are obtained from the position, respectively; R wave during cuff deflation between systolic and diastolic blood pressure - Korotkoff sound in To obtain a signal related to the slope of a straight line that fits turval versus cuff pressure, Processing a signal periodically, the slope associated with the signal is determined to be the blood pressure during the cuff deflation. 8. The method of claim 7 relating to the contraction slope of the wave. /l slope associated with said signal versus the pair obtained from processing said R-wave signal 71. The method of claim 70, comprising recording the elephant's heart rate. /2. For additional equipment used in the diagnosis and/or screening of subjects for coronary artery disease. There, An inflatable clip adapted to wrap around the subject's arm, Inflate and deflate the cuff to a pressure range that produces Korotkoff sounds. a cuff pressure device and an output signal responsive to and related to cuff pressure; A pressure transducer device that detects electrocardiograph signals from the subject, and an electrode device that detects electrocardiograph signals from the subject. , an R-wave peak detector device for detecting an R-wave peak in an electrocardiograph signal; a transducer device that senses Korotkoff sounds during cuff deflation; The Korotkoff sound transducer in the output of the Korotkoff sound transducer a Korotkoff sound detection device for detecting sounds; the pressure to generate a signal representing the contraction slope of the blood pressure wave during cuff deflation. Drans juicer device, R-wave peak detector device, and Korotkoff sound detector a device responsive to output from the device; Representing the contraction slope during different periods of the activity cycle performed by the subject and apparatus for periodically obtaining said signal, thereby controlling the time during said activity cycle. Changes in the group may be used to diagnose and/or screen subjects with coronary artery disease. A device designed to be used in /3. Claim 7. further comprising a device for displaying said signal representing a contraction slope. The device according to item 2. /lA The display provided by the display device is a representation of the contraction slope. 74. The apparatus of claim 73, comprising a plot of heart rate versus subject's heart velocity. 15. The display provided by the display device is a representation of the signal representing the contraction slope. 14. The apparatus of claim 13, comprising a plot of time versus time. /B The device that generates a signal representing the contraction slope of a blood pressure wave is a device for accumulating a plurality of cuff pressure values and an associated RK interval; The interval is between the arrival of the output from the R-wave peak detector device and the time between the arrival of the associated Korotkoff sound signal from the sound detection device constructed and related to the RK interval obtained during cuff deflation. It includes a device that fits a straight line to the cuff pressure value, and the slope of the straight line is the systolic slope of the blood pressure wave. 73. The device of claim 72, wherein the device is inversely proportional to the rope. /7. a display device for displaying a plot of the slope of the straight line versus cardiac velocity; The apparatus according to claim 1, item (B). /! r. in a method of screening a subject for coronary artery disease; Periodically obtaining a measured value of the contraction slope of the target branch arterial blood pressure wave; The subject executes an activity protocol that includes a pause before the activity, an activity, and a pause after the activity. provide a plot of said measurements of slope obtained over a period of time; and , evaluating the plot based on a plurality of different parameters; weighting the values obtained from the evaluation and summing the weighted values; Predetermined cut 7, total outside the range of points associated with coronary artery disease Target 3 A method characterized in that it is used to identify. /9. The plurality of parameters are based on the speed obtained while the subject is at rest before being active. 1g. A method according to claim 1g, comprising rope measurements. The plurality of 79 parameters are the slope measurements during the beginning of the activity protocol. 1g. The method of claim 1g, including rate of change. 2A The above multiple ! The parameters plotted at the beginning of the activity protocol A method as claimed in any preceding claim, including a slope of . 2. The plurality of parameters are in the direction of the slope measurements during the activity protocol. 2. A method as claimed in claim 1, comprising detecting a change in . J, the plurality of parameters are slope measurements during the post-activity period during the activity protocol. 1g. The method of claim 1g, including the amount of change in a fixed value. The plurality of parameters are the time frames that appear during the post-activity period during the activity protocol. The method according to claim 1, comprising the rate of change in the constant value of the rope. . 2. The plurality of parameters are the slope that appears after the activity in the activity protocol. The method according to claim 1, which includes the highest temperature value of the measured values. /