JP4627418B2 - Vascular sclerosis evaluation apparatus, vascular sclerosis calculation apparatus, and vascular sclerosis calculation program - Google Patents

Description

  The present invention relates to a vascular sclerosis degree evaluation apparatus and a vascular sclerosis degree calculation apparatus for evaluating or calculating a vascular sclerosis degree, and a vascular sclerosis degree that is executed in an arithmetic processing device and operates as the vascular sclerosis degree calculating device. It relates to a calculation program.

  In recent years, with the increasing aging society, early diagnosis and treatment of early treatment of arteriosclerotic diseases are urgently needed. To this end, first, it is necessary to correctly measure and evaluate how far arteriosclerosis has progressed.

  As one of the techniques for non-invasive quantitative diagnosis of arteriosclerosis, there is known an aortic pulse wave velocity test method for measuring a pulse wave velocity (PWV) which is a propagation velocity of a pulse wave between two points of the aorta. It has been.

  It is known that the pulse wave velocity is fast in a hard substance, slow in a soft substance, and a healthy artery wall is soft and elastic, and an arteriosclerotic blood vessel wall is hard and brittle. The aortic pulse wave velocity test method uses this property, and roughly speaking, the propagation velocity of the pulse wave between two points of the aorta is measured, and the higher the velocity, the more diagnosed the arteriosclerosis is. To do. This pulse wave velocity (PWV) is usually expressed in units of m / sec.

  FIG. 1 is a schematic diagram illustrating an example of a pulse wave velocity measurement method. The pulse wave velocity measuring method shown in FIG. 1 is a measuring method called a Frank method.

  Here, as shown in FIG. 1A, two pulse wave sensors are used to measure the pulse waves of the carotid artery and the femoral artery, respectively. Further, distances a and b + c from the aortic valve opening to each pulse wave measurement point are measured. The measurement between the aortic valve opening and the pulse wave sensor for measuring the femoral artery with a broken line (distance b and distance c) without taking a straight line is based on a path along which the aorta extends.

  FIG. 1B shows the carotid artery wave (a) and the femoral artery wave (b) measured by each pulse wave sensor.

  A time T between predetermined rising points of these pulse waves, for example, points rising by 1/5 of the peak value is obtained.

  Thus, by obtaining the distances a, b, c and time T, the pulse wave velocity PWV is

Is required.

  Patent Document 1 discloses an improved technique based on the above pulse wave velocity measurement method. In Patent Document 1, pulse waves of the brachial artery and ankle arteries are measured instead of the pulse waves of the carotid artery and the femoral artery.

  FIG. 2 is a schematic view showing another example of the pulse wave velocity measuring method. The pulse wave velocity measuring method shown in FIG. 2 is a measuring method called the Yoshimura method.

  Similar to the Frank method shown in FIG. 1, in addition to the two sensors for measuring the pulse waves of the carotid artery and the femoral artery, sensors are also arranged at the aortic valve opening to measure the starting point of the II sound. Further, the linear distance D between the aortic valve opening and the femoral artery pulse wave measurement sensor is measured. In order to correct the difference between the straight line distance D and the actual path of the artery, the straight line distance D is multiplied by 1.3.

  Further, the time II from the rise timing of the carotid artery wave to the rise of the femoral artery wave and the II sound timing of the aortic valve opening shown in FIG. The time t until the timing when the sound is captured is measured.

  Thus, by calculating the linear distance D and the times T and t, the pulse wave velocity PWV is

Is required.

  Here, the pulse wave velocity varies depending on the blood pressure. This is because when the blood pressure rises, the blood vessel is pushed and expanded by the blood, and the blood vessel is apparently hardened.

  FIG. 3 is a graph showing the relationship between minimum blood pressure (diastolic blood pressure) and aortic pulse wave velocity. FIG. 3 shows the relationship between the minimum blood pressure (diastolic blood pressure) and the aortic pulse wave velocity in 73 cases.

  As shown in FIG. 3, when the blood pressure increases, the aortic pulse wave velocity also increases.

  FIG. 4 is a diagram showing a pulse wave velocity correction curve.

  As shown in FIG. 3, the pulse wave velocity changes depending on the blood pressure. Therefore, a large number of cases as shown in FIG. 3 are statistically analyzed, and a pulse wave velocity correction curve is obtained as shown in FIG. In the actual measurement, the pulse wave velocity is measured and the blood pressure is measured, and the measured pulse wave velocity is converted into the pulse wave velocity when the minimum blood pressure (diastolic blood pressure) is 80 mmHg according to the pulse wave velocity correction curve shown in FIG. To do. Here, the pulse wave velocity when converted to the pulse wave velocity when the minimum blood pressure (diastolic blood pressure) is 80 mmHg is expressed as PWV ′.

  Also in Patent Document 1, this blood pressure correction is performed.

  By doing so, it does not depend on the blood pressure at the time of measuring the pulse wave of the case. The pulse wave velocity of the case is obtained, and atherosclerosis is diagnosed based on the pulse wave velocity.

In addition, Non-Patent Documents 1 and 2 are listed for later explanation.
Japanese Patent No. 3140007 “Diagnosis of human carotid sinus sclerosis by Stiffness Parameter β” Angiology Vol. 25, no. 80.1985 p. 1199-1204 "Artificial Stiffness and Plus Wave Velocity Clinical Applications" Rolland ASMAR, 1999

  As described above, blood pressure is also measured at the time of measuring the pulse wave velocity, and the measured pulse wave velocity is corrected by the blood pressure. It can be used for diagnosis of various diseases caused by sclerosis.

  Here, arteriosclerosis does not always progress in the same state throughout the whole body, and may differ for each part of the body. Therefore, in order to accurately examine the progress of arteriosclerosis, a measurement method that can easily measure the pulse wave velocity of blood vessels in various parts of the body is preferable.

  However, in the case of the above-described pulse wave velocity measurement method, it is necessary to correct the blood pressure. For this purpose, it is necessary to obtain a correction curve as shown in FIG. 4 in advance with high accuracy. FIG. 4 shows a correction curve when a specific part of the aorta is measured by a specific pulse wave measurement method. The correction curve as shown in FIG. 4 is different for each part of the body. It is extremely difficult to obtain the correction curve for each of various parts of the body with high accuracy. Therefore, conventionally, the pulse wave velocity measuring method has been adopted as a measuring method for measuring a specific part as shown in FIGS.

  In view of the above circumstances, the present invention provides a vascular sclerosis degree evaluation apparatus and a vascular sclerosis degree calculation apparatus suitable for simply evaluating and calculating the degree of vascular hardening, and an arithmetic processing apparatus that performs an operation by executing a program. An object of the present invention is to provide a blood vessel sclerosis degree calculation program that operates as a vascular sclerosis degree calculation device.

The first vascular sclerosis degree evaluation apparatus of the vascular sclerosis degree evaluation apparatus of the present invention that achieves the above object comprises a pulse wave velocity measuring unit for obtaining a pulse wave velocity PWV, a systolic blood pressure Ps, and a diastolic blood pressure Pd. Using the blood pressure measurement unit for obtaining blood pressure, the pulse wave velocity obtained by the pulse wave velocity measurement unit and the blood pressure obtained by the blood pressure measurement unit,
Ln (Ps / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Ps−Pd
It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including the evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit ,
The evaluation value calculation unit calculates the evaluation value β.
β = 2ρ · Ln (Ps / Pd) · PWV ² / ΔP
Where ρ is the blood density.
Is calculated .

The first vascular sclerosis degree calculation device of the vascular sclerosis degree calculation apparatus according to the present invention that achieves the above object includes data representing pulse wave velocity PWV or data for calculating pulse wave velocity, systolic blood pressure Ps and Using a data acquisition unit that acquires data representing blood pressure consisting of diastolic blood pressure Pd or data for blood pressure calculation, and data acquired by the data acquisition unit,
Ln (Ps / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Ps−Pd
It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including the evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit ,
The evaluation value calculation unit calculates the evaluation value β.
β = 2ρ · Ln (Ps / Pd) · PWV ² / ΔP
Where ρ is the blood density.
Is calculated .

Furthermore, the first vascular sclerosis degree calculation program of the vascular sclerosis degree calculation program of the present invention that achieves the above object is executed in an arithmetic processing device that executes the program, and the arithmetic processing device is used as the pulse wave velocity PWV. Acquired by the data acquisition unit, the data acquisition unit for acquiring the data representing the blood pressure or the data for calculating the pulse wave velocity, the data representing the blood pressure composed of the systolic blood pressure Ps and the diastolic blood pressure Pd, or the data for blood pressure calculation Using data,
Ln (Ps / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Ps−Pd
It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of hardening of a blood vessel based on an arithmetic expression that includes an evaluation value output unit that outputs an evaluation value calculated by the evaluation value calculation unit A blood vessel sclerosis calculation program that operates as a device ,
The evaluation value calculation unit calculates the evaluation value β.
β = 2ρ · Ln (Ps / Pd) · PWV ² / ΔP
Where ρ is the blood density.
Is calculated .

  Conventionally, a stiffness parameter β shown in the following equation (1) is known as a parameter representing the hardness of a blood vessel (see Non-Patent Document 1 described above).

β = Ln (Ps / Pd) · (D / ΔD) (1)
Where Ps: systolic blood pressure
Pd: Diastolic blood pressure
D: Diastolic vessel radius
ΔD: Increase in blood vessel radius
Ln: natural logarithm with e as the base
It is.

  However, in equation (1) representing the stiffness parameter β, the radius D of the blood vessel and its change ΔD, which cannot be easily measured, are included as variables. Therefore, here, it is considered to replace the radius D of the blood vessel and the change ΔD in the equation (1) with variables that can be measured easily and inexpensively.

  Here, as an equation related to the pulse wave velocity PWV, a Bramwell-Hill equation shown in the following equation (2) is known (see Non-Patent Document 2 described above).

PWV ² = {(ΔP) · V} / {(ΔV) · ρ}
= (ΔP / ρ) · (V / ΔV) (2)
However, ΔP = Ps−Pd
ρ: Blood density
V: Vessel volume ΔV: Vessel volume variation The blood vessel can be considered by a cylindrical model.
V = (π · L · D ² ) (3)
It becomes. This equation (3) represents that the volume V is obtained by multiplying the square of the radius D by the circumference ratio π and the length L, and therefore
(ΔV) / V = {πL (D + ΔD) ² −πLD ² } / (πLD ² )
= {2D (ΔD) ² + (ΔD) ² } / D ²
= (2ΔD) / D + (ΔD / D) ² (4)
Here, since D >> (ΔD), (ΔD / D) ² in the equation (4) is sufficiently small and can be ignored as compared with (2ΔD) / D. Therefore, equation (4) becomes
(ΔV) / V = (2ΔD) / D (5)
Can be expressed as

When this equation (5) is transformed,
{D / (ΔD)} / 2 = {V / (ΔV)} (6)
It becomes. Substituting this equation (6) into equation (2),
PWV ² = (ΔP / ρ) · (D / ΔD) / 2
= {(ΔP) / (2ρ)} · (D / ΔD) (7)
This equation (7) is transformed,
D / ΔD = PWV ² / {(ΔP) / (2ρ)} (8)
Substituting this equation (8) into equation (1),
β = Ln (Ps / Pd) · PWV ² / {(ΔP) / (2ρ)} (9)
It becomes. Where ρ is the blood density and is a constant,
K = 2ρ (10)
Then, equation (9) becomes
β = K · Ln (Ps / Pd) · PWV ² / (ΔP) (11)
It becomes.

  This equation (11) uses the pulse velocity PWV and blood pressure (systolic blood pressure Ps and diastolic blood pressure Pd, ΔP is (Ps−Pd)) as variables, and these pulse velocity PWV Both blood pressure (systolic blood pressure Ps and diastolic blood pressure Pd) can be measured non-invasively and simply, and therefore the stiffness parameter β that is an index of the degree of vascular hardening can be easily obtained.

The second vascular sclerosis degree evaluation apparatus of the vascular sclerosis degree evaluation apparatus of the present invention that achieves the above object includes a pulse wave velocity measurement unit that obtains a pulse wave velocity PWV, and a blood pressure that includes an average blood pressure Pm and a diastolic blood pressure Pd. Using the blood pressure measurement unit for obtaining the pulse wave velocity obtained by the pulse wave velocity measurement unit and the blood pressure obtained by the blood pressure measurement unit,
Ln (Pm / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Pm−Pd
It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including the evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit ,
As the evaluation value β, the evaluation value calculation unit
β = 2ρ · Ln (Pm / Pd) · PWV ² / ΔP
Where ρ is the blood density.
Is calculated .

  Here, in the second vascular sclerosis evaluation apparatus according to the present invention, the blood pressure measurement unit may obtain the maximum blood pressure of the pulse group as the average blood pressure Pm when the oscillometric method is adopted.

The second vascular sclerosis degree calculation apparatus of the vascular sclerosis degree calculation apparatus of the present invention that achieves the above object includes data representing the pulse wave velocity PWV or data for calculating the pulse wave velocity, the average blood pressure Pm, and the expansion. Using a data acquisition unit for acquiring data representing blood pressure consisting of the period blood pressure Pd or data for blood pressure calculation, and data acquired by the data acquisition unit,
Ln (Pm / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Pm−Pd
It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including the evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit ,
As the evaluation value β, the evaluation value calculation unit
β = 2ρ · Ln (Pm / Pd) · PWV ² / ΔP
Where ρ is the blood density.
Is calculated .

  Here, in the second vascular stiffness calculation apparatus of the present invention, the data acquisition unit uses the oscillometric method as the data representing the average blood pressure Pm or the data for calculating the average blood pressure Pm. Data representing the blood pressure at the point or data for calculating the blood pressure at the maximum point may be acquired.

Furthermore, the second vascular stiffness calculation program of the vascular stiffness calculation program of the present invention that achieves the above object is executed in an arithmetic processing device that executes the program, and the arithmetic processing device is used as the pulse wave velocity PWV. Or data for pulse wave velocity calculation and data acquisition unit for acquiring blood pressure data or data for blood pressure calculation including average blood pressure Pm and diastolic blood pressure Pd, and data acquired by the data acquisition unit Use
Ln (Pm / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Pm−Pd
It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of hardening of a blood vessel based on an arithmetic expression that includes an evaluation value output unit that outputs an evaluation value calculated by the evaluation value calculation unit A blood vessel sclerosis calculation program that operates as a device ,
The evaluation value calculation unit calculates the evaluation value β.
β = 2ρ · Ln (Pm / Pd) · PWV ² / ΔP
Where ρ is the blood density.
Is calculated .

  Here, also in the second vascular sclerosis calculation program of the present invention, the data acquisition unit uses the oscillometric method as the data representing the average blood pressure Pm or the data for calculating the average blood pressure Pm. Data representing the maximum blood pressure or data for calculating the maximum blood pressure may be acquired.

  The second vascular sclerosis degree evaluation apparatus, the second vascular sclerosis degree calculation apparatus, and the second vascular sclerosis degree calculation program according to the present invention are the first vascular sclerosis degree evaluation apparatus and the first vascular sclerosis degree, respectively. This is equivalent to the degree of blood pressure Ps in the first degree of blood vessel sclerosis degree calculation program replaced with the average blood pressure Pm. With this replacement, ΔP = Ps−Pd is also replaced with ΔP = Pm−Pd.

  When blood pressure is measured by the oscillometric method, the maximum blood pressure of the pulse wave obtained in the cuff decompression process is obtained as the average blood pressure Pm. The average blood pressure Pm is compared with the systolic blood pressure Ps and the diastolic blood pressure Pd. Can be obtained with high accuracy. In obtaining the pulse wave velocity PWV, as shown in FIG. 1 and FIG. 2, the rise timing of the pulse wave waveform and the notch (II sound of the aortic valve opening) existing near the peak on the pulse wave waveform are obtained. ), The pulse wave velocity PWV is obtained, but the rise timing of the pulse wave waveform (corresponding to the bottom of the pulse wave) corresponds to the diastolic blood pressure Pd and is close to the peak of the pulse wave waveform. The timing of the existing notch (substantially corresponding to the peak on the pulse waveform) corresponds to the average blood pressure Pm. From this point, instead of using the systolic blood pressure Ps, the average blood pressure Pm is used, and the ratio (Pm / Pd) or difference (ΔP = Pm−Pd) between the average blood pressure Pm and the diastolic blood pressure Pd is used as a variable. By adopting, a highly accurate evaluation value can be obtained.

  Further, the arithmetic expression in which the systolic blood pressure Ps is replaced with the average blood pressure Pm is obtained by using the pulse wave velocity PWV and blood pressure (mean blood pressure Pm and diastolic blood pressure Pd, ΔP = Pm−Pd as variables. Conversion can also be measured non-invasively and simply.

  As described above, according to the present invention, the degree of vascular hardening can be easily evaluated and calculated.

  Embodiments of the present invention will be described below.

  FIG. 5 is a block diagram showing an embodiment of the vascular stiffness evaluation apparatus of the present invention.

  The vascular stiffness evaluation apparatus 100 includes a pulse wave velocity measurement unit 101, a blood pressure measurement unit 102, an evaluation value calculation unit 103, and an evaluation value output unit 104.

  In the pulse wave velocity measuring unit 101, the pulse wave velocity PWV of the measurement target part is measured by the pulse wave sensor. As described with reference to FIGS. 1 and 2, there are several types of pulse wave velocity measuring methods, but the method is not limited to a specific measuring method here.

  The pulse wave velocity measuring method itself is a well-known technique, and further evaluation explanation is omitted here.

  In the blood pressure measurement unit 102, the systolic blood pressure (maximum blood pressure) Ps and the diastolic blood pressure (minimum blood pressure) Pd of the measurement target site are measured by the blood pressure monitor. The blood pressure measurement method itself is also a well-known technique, and detailed description thereof is omitted.

The evaluation value calculation unit 103 uses the pulse wave velocity obtained by the pulse wave velocity measurement unit 101 and the blood pressure obtained by the blood pressure measurement unit 102,
Ln (Ps / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Ps−Pd
It is.
An evaluation value that indicates the degree of sclerosis of the blood vessel at the measurement target site is calculated based on an arithmetic expression including. Specific examples will be described later.

  The evaluation value output unit 104 outputs the evaluation value calculated by the evaluation value calculation unit. The output mode of the evaluation value is not limited to a specific output mode. For example, the evaluation value is output on the display screen or printed out by a printer. Further, data representing the evaluation value is output to the outside. (Sent).

  FIG. 6 is a block diagram showing an embodiment of the vascular sclerosis degree calculation apparatus of the present invention.

  This vascular sclerosis degree calculation device 200 includes a data acquisition unit 201, an evaluation value calculation unit 202, and an evaluation value output unit 203.

  Compared with the blood vessel sclerosis degree evaluation apparatus 100 shown in FIG. 5, the blood vessel sclerosis degree calculation apparatus 200 does not include the pulse wave velocity measurement unit 101 and the blood pressure measurement unit 102. The pulse wave velocimeter for measuring the pulse wave velocity and the sphygmomanometer for measuring the blood pressure may be existing ones. If an existing pulse wave velocimeter or sphygmomanometer is used, these pulse wave velocimeters The evaluation value may be calculated and output by taking in the pulse wave velocity data and blood pressure data obtained by the sphygmomanometer. The blood vessel sclerosis calculating apparatus 200 of FIG. 6 is configured based on this idea. In the data acquisition unit 201 constituting the vascular stiffness calculation apparatus 200 in FIG. 6, data representing the pulse wave velocity PWV of the measurement target region and data representing the blood pressure (systolic blood pressure Ps and diastolic blood pressure Pd) of the measurement target region. Is acquired.

  Alternatively, the data acquisition unit 201 does not directly represent the pulse wave velocity PWV, but data for calculating the pulse wave velocity PWV, for example, as shown in FIG. 1 (B) or FIG. 2 (B). Waveform data representing a waveform may be acquired from the outside, and the pulse wave velocity PWV may be obtained based on the waveform data inside the data acquisition unit 201.

  Similarly, the data acquisition unit 201 acquires the blood pressure calculation data from the outside even if it is not data directly representing the blood pressure, and based on the blood pressure calculation data, the data acquisition unit 201 You may ask for blood pressure.

  The operation of the evaluation value calculation unit 202 and the evaluation value output unit 203 constituting the vascular sclerosis degree calculating device 200 in FIG. 6 is the same as the evaluation value calculating unit 103 and the evaluation value output unit constituting the vascular sclerosis degree evaluating device 100 in FIG. Each operation 104 is the same as each other, and redundant description is omitted.

  In the present embodiment, the vascular sclerosis degree calculation device 200 shown in FIG. 6 is composed of a combination of a computer and a program executed in the computer. Therefore, first, the configuration of the computer will be described below.

  FIG. 7 is an external view of a computer that operates as an embodiment of the vascular sclerosis calculation apparatus of the present invention.

  The computer 10 includes a main body 11 incorporating a CPU, a RAM, a hard disk and the like, a display 12 that displays a screen on a display screen 12a according to an instruction from the main body 11, and an operator's instruction and character information in the computer. And a mouse 14 for inputting an instruction corresponding to an icon or the like displayed at that position by designating an arbitrary position on the display screen 12a.

  The main body 11 further has a flexible (FD) 22 (not shown in FIG. 7; see FIG. 8) and a FD loading port 11a and a CDROM loading port 11b into which the CDROM 20 is loaded. Inside, an FD drive 116 and a CDROM drive 117 (see FIG. 8) for driving the loaded FD and CDROM are also incorporated.

  Here, a blood vessel sclerosis degree calculation program according to the present invention is stored in the CDROM 20, and this CDROM 20 is loaded into the main body 11 from the CDROM loading port 11b, and the blood vessel sclerosis degree calculation stored in the CDROM 20 by the CDROM drive 117 is calculated. The program is installed in the hard disk of this computer. When the blood vessel sclerosis degree calculation program installed in the hard disk of this computer system is activated, this computer operates as an embodiment of the vascular sclerosis degree calculation apparatus of the present invention.

  FIG. 8 is a hardware configuration diagram of a computer having the appearance shown in FIG.

  Here, there are a central processing unit (CPU) 111, a RAM 112, input interfaces 113a and 113b, a printer interface 114, a hard disk controller 115, an FD drive 116, a CDROM drive 117, a mouse controller 118, a keyboard controller 119, and a display controller 120. They are connected to each other by a bus 110.

  As described with reference to FIG. 7, the FD drive 116 and the CDROM drive 117 are loaded with the FD22 and the CDROM20, and access the loaded FD22 and CDROM20.

  Further, a pulse wave velocimeter (corresponding to the pulse wave velocity measuring unit 101 in FIG. 5) and a sphygmomanometer (corresponding to the blood pressure measuring unit 102 in FIG. 5) are connected to the two input interfaces 113a and 113b, respectively. The pulse wave velocity data and blood pressure data of the measurement target site measured by the pulse wave velocity meter and the blood pressure monitor are input.

  The printer interface 114 is connected to a printer that prints out images and characters on paper, and blood vessel stiffness evaluation value data calculated inside the computer is sent to the printer via the printer interface 114. The blood vessel sclerosis evaluation value is printed out by the printer.

  5 also shows the hard disk 21 accessed by the hard disk controller 113, the mouse 14 controlled by the mouse controller 116, the keyboard 13 controlled by the keyboard controller 117, and the display 12 controlled by the display controller 118. ing.

  As described above, the blood vessel sclerosis degree calculation program is stored in the CDROM 20, and the blood vessel sclerosis degree calculation program is read from the CD ROM 20 by the CDROM drive 117, and is stored in the hard disk 21 by the hard disk controller 115 via the bus 110. Stored. In actual execution, the blood vessel hardening degree calculation program in the hard disk 21 is loaded onto the RAM 112 and executed by the CPU 111.

  On the display 12, an evaluation value representing the degree of vascular sclerosis calculated in the computer is displayed, and input information from the keyboard 13 and the mouse 14 is displayed.

  FIG. 9 is a conceptual configuration diagram of the blood vessel sclerosis degree calculation program stored in the CD ROM 20 shown in FIGS.

  The blood vessel sclerosis degree calculation program 300 shown here includes a data acquisition unit 301, an evaluation value calculation unit 302, and an evaluation value output unit 303. When the blood vessel sclerosis degree calculation program 300 is installed in the computer 10 shown in FIG. 7 and executed, the operations of the units 301 to 303 constituting the blood vessel sclerosis degree calculation program 300 are as follows. The operation is the same as that of the units 201 to 203 constituting the calculation device 200. That is, the data acquisition unit 201 included in the vascular sclerosis degree calculation device 200 illustrated in FIG. 6 includes a data acquisition unit 301 as a program component included in the vascular sclerosis degree calculation program 300 illustrated in FIG. It is configured by combining with the CPU 111 to be executed and the input interfaces 113a and 113b responsible for data acquisition.

  Moreover, the evaluation value calculation part 202 which comprises the vascular sclerosis degree calculation apparatus 200 shown in FIG. 6 is the evaluation value calculation part 302 as a program component which comprises the vascular sclerosis degree calculation program 300 shown in FIG. It is configured by combining with the CPU 111 or the like that executes the unit 302.

  Furthermore, the evaluation value output unit 203 constituting the vascular sclerosis degree calculation device 200 shown in FIG. 6 includes an evaluation value output unit 303 as a program component constituting the vascular sclerosis degree calculation program 300 shown in FIG. A CPU 111 that executes the unit 303, a display 12 that displays an evaluation value, a display controller 120 that controls the display 12, and a printer interface 114 that outputs the evaluation value to a printer are combined.

  Next, evaluation value calculation units 103 and 202 constituting the vascular sclerosis degree evaluation apparatus and the vascular sclerosis degree calculation apparatus shown in FIGS. 5 and 6, that is, an evaluation value calculation part 302 (program parts) executed by the CPU 111. A specific example of evaluation value calculation in FIG. 9) will be described.

  Hereinafter, an arithmetic expression for obtaining the evaluation value and an evaluation example based on the arithmetic expression will be described.

Here, as an arithmetic expression for obtaining the evaluation value, the above-described expression (9), that is,
β = Ln (Ps / Pd) · PWV ² / {(ΔP) / (2ρ)} (9)
Is adopted.

Apart from this calculation formula, as a calculation formula for obtaining an evaluation value that indicates the degree of sclerosis of blood vessels,
CAVI = Ln (Ps / Pd) · 1 / k ² · PWV ² (14)
Has been proposed (Japanese Patent Application No. 2003-379902).

  Therefore, here, an evaluation example based on these arithmetic expressions will be described while comparing the expressions (9) and (14).

  Comparing equation (9) and equation (14), since ρ and k are both constants, ignoring the difference between these constants, in essence, equation (9) Corresponds to the equation divided by ΔP). Since the pulse pressure (ΔP) is ΔP = Ps−Pd, when a large difference occurs between the systolic blood pressure Ps and the diastolic blood pressure Pd, the systolic blood pressure Ps and the diastolic blood pressure are expressed with respect to the equation (14). Insufficient correction is corrected only by the logarithm Ln (Ps / Pd) of the ratio Ps / Pd of Pd. On the other hand, in the case of Equation (9), the pulse pressure is added in addition to the correction of the logarithm Ln (Ps / Pd). Since (ΔP) is also corrected, the blood pressure fluctuation is corrected more accurately than in equation (14), the evaluation value indicating the degree of vascular stiffness is obtained, the influence of the blood pressure fluctuation is suppressed, and the blood pressure fluctuation is less affected. be able to.

  Here, verification of the above formulas (9) and (14) was carried out on a patient on artificial dialysis. Since patients with artificial dialysis have advanced arteriosclerosis, their blood pressure tends to fluctuate greatly, whereas the essential characteristics of the patient's blood vessels do not change significantly in a short period of time. For this reason, dialysis patients are appropriate to verify how the measured values of β (Equation (9)) and CAVI (Equation (14)) are affected by large blood pressure fluctuations. Conceivable.

  The time interval between each measurement is within two weeks from the same day, but is not constant for the convenience of the patient. Since it is considered that the blood vessel characteristics do not change in a short time, this time interval is not a problem as a time interval for verification of β and CAVI.

  FIG. 10 and FIG. 11 are diagrams showing the evaluation values β and CAVI in the first examination for the patient on artificial dialysis and the second evaluation values β and CAVI connected by a straight line for each patient. It corresponds to an example of the invention and a comparative example.

  FIGS. 12 and 13 show the same data as those shown in FIGS. 10 and 11 with different expressions. The horizontal axis represents the evaluation values β and CAVI in the first test for the patient on artificial dialysis. It is the figure which showed the regression line while plotting evaluation value (beta) and CAVI for every patient on the vertical axis | shaft with the 2nd evaluation value (beta) and CAVI. 12 and 13 correspond to examples and comparative examples of the present invention, respectively.

  In FIGS. 10 and 11, the straight line connecting the first evaluation value and the second evaluation value of the same patient is closer to the horizontal, meaning that the blood pressure is not affected, and in FIGS. 12 and 13, The smaller the variation, the less affected by blood pressure.

  As can be seen from FIGS. 10 to 13, the example (evaluation value β) of the present invention shown in FIGS. 10 and 12 has an effect of blood vessels more than the comparative example (evaluation value CAVI) shown in FIGS. 11 and 13. Evaluation value that is difficult to receive is obtained.

  In the verification results shown here, the first and second correlation coefficients R are R = 0.890 for the evaluation value β and R = 0.626 for the evaluation value CAVI. It can also be seen that the evaluation value β is less susceptible to blood pressure than the evaluation value CAVI.

  FIG. 14 is a diagram illustrating a correspondence relationship between the pulse wave velocity and the evaluation value β obtained by Expression (9).

  The horizontal axis represents the pulse wave velocity PWV ′ when converted to the minimum blood pressure (diastolic blood pressure) 80 mmHg, and the vertical axis represents the evaluation value β obtained by the equation (9).

  The above is the implementation of the first vascular sclerosis evaluation apparatus, the first vascular sclerosis calculation apparatus, and the first vascular sclerosis calculation program (hereinafter collectively referred to as the “first invention”) of the present invention. Next, the second vascular sclerosis evaluation apparatus, the second vascular sclerosis calculation apparatus, and the second vascular sclerosis calculation program (hereinafter collectively referred to as “second”. (Referred to as “invention”).

  Hereinafter, with reference to FIGS. 5 to 9 as they are, only differences from the embodiment of the first invention will be described.

  FIG. 5 is a block diagram showing an embodiment of the vascular sclerosis degree evaluation apparatus as described above.

  In the embodiment described here, the oscillometric method is employed to measure the blood pressure of the patient in the blood pressure measurement unit 102 of the vascular stiffness evaluation apparatus 100 shown in FIG. Pd is measured. The oscillometric method is a well-known blood pressure measurement method, and detailed description thereof is omitted here.

The evaluation value calculation unit 103 uses the pulse wave velocity PWV obtained by the pulse wave velocity measurement unit 101 and the blood pressure obtained by the blood pressure measurement unit 102.
Ln (Pm / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Pm−Pd
It is.
An evaluation value that indicates the degree of sclerosis of the blood vessel at the measurement target site is calculated based on an arithmetic expression including. A specific example of the arithmetic expression will be described later.

  FIG. 6 is a block diagram showing an embodiment of the vascular sclerosis degree evaluation apparatus as described above.

  In the data acquisition unit 201 constituting the vascular sclerosis calculation device 200 of FIG. 6, data representing the pulse wave velocity PWV of the measurement target region and data representing the blood pressure (average blood pressure Pm and diastolic blood pressure Pd) of the measurement target region. Acquisition is performed.

  Alternatively, the data acquisition unit 201 does not directly represent the pulse wave velocity PWV, but data for calculating the pulse wave velocity PWV, for example, as shown in FIG. 1 (B) or FIG. 2 (B). Waveform data representing a waveform may be acquired from the outside, and the pulse wave velocity PWV may be obtained based on the waveform data inside the data acquisition unit 201.

  Similarly, the data acquisition unit 201 acquires the blood pressure calculation data from the outside even if the data does not directly represent the blood pressure, and the data acquisition unit 201 uses the blood pressure calculation data as a basis. You may ask for blood pressure.

  The operation of the evaluation value calculating unit 202 constituting the vascular sclerosis degree calculating device 200 in FIG. 6 is the systolic blood pressure Ps, ΔP = Ps−Pd in the evaluation value calculating unit 103 constituting the vascular sclerosis degree evaluating device 100 in FIG. Instead, the action is the same as when the average blood pressure Pm, ΔP = Pm−Pd is adopted.

  FIG. 9 is a conceptual configuration diagram of the blood vessel sclerosis degree calculation program stored in the CDROM 20 shown in FIGS. 7 and 8 as described above.

  Again, compared to the first embodiment of the present invention, only the mean blood pressure Pm, ΔP = Pm−Pd is employed instead of the systolic blood pressure Ps, ΔP = Ps−Pd. Therefore, further detailed description is omitted.

Below, as an example of an arithmetic expression for obtaining an evaluation value in the second invention,
CAVIβm = K × Ln (Pm / Pd) · PWV ² / (ΔP) (15)
However, ΔP = Pm−Pd
K is a constant
It is.
Is adopted.

As a comparative example, the above-mentioned formula (14), that is, CAVI = Ln (Ps / Pd) · 1 / k ² · PWV ² (14)
An evaluation example based on these arithmetic expressions will be described while comparing the expressions (14) and (15).

  Comparing equation (14) and equation (15), since K and k are both constants, if the difference between these constants is ignored, equation (15) can be expressed as Corresponds to the equation divided by ΔP). However, here, ΔP = Pm−Pd. Another is that systolic blood pressure Ps is employed in equation (14), while mean blood pressure Pm is employed in equation (15).

FIG. 15 is a diagram illustrating a correspondence relationship between the pulse wave velocity and the evaluation value CAVI obtained by Expression (14). This figure corresponds to a comparative example for the present invention.

  The horizontal axis represents the pulse wave velocity PWV 'when converted to a minimum blood pressure (diastolic blood pressure) of 80 mmHg, and the vertical axis represents the evaluation value CAVI obtained by equation (14).

Here, in determining the constant k in equation (14), the aortic pulse wave velocity PWV and blood pressure (systolic blood pressure Ps and diastolic blood pressure Pd) are measured and converted for many patients suspected of having arteriosclerosis. The obtained pulse wave velocity PWV ′ is obtained, and CAVI is obtained according to the equation (14) while leaving k as a variable, and a constant k is determined so that these values statistically match each other. Each point in Figure 1 5 represents the relationship between CAVI according to this way-determined each person PWV 'in the formula (14). The curve shown in FIG. 1 5 represents a regression quadratic curve thereof a number of respects. The reason why the quadratic curve is adopted is that PWV ² is included as a variable in the equation (14). The dispersion R here is R = 0.91.

FIG. 16 is a diagram showing a correspondence relationship between the pulse wave velocity and the evaluation value CAVIβm obtained by Expression (15). This figure corresponds to an embodiment of the second invention of the present invention.

The horizontal axis is the case in FIG. 1 5 similarly, the minimum blood pressure (diastolic blood pressure) aortic pulse wave velocity PWV when converted into 80 mmHg '. The vertical axis represents the evaluation value CAVIβm obtained by equation (15).

Here, the formula when determining the constant K in (15) in the case of FIG. 1 5 and similar, a number of patients aortic pulse wave velocity and blood pressure suspected of arteriosclerosis (diastolic and mean blood pressure Pm is here The blood pressure Pd) is measured, and when the converted pulse wave velocity PWV ′ and CAVIβm defined by the equation (15) are obtained, a constant k is determined so that these values statistically match each other. . Each point in FIG. 16 represents the relationship between each person's PWV ′ determined in this way and CAVIβm in Expression (15). Curve shown in FIG. 1 6 is also similar to the case of FIG. 1 5 represents a regression quadratic curve thereof a number of respects. The reason why the quadratic curve is adopted is that PWV ² is also included as a variable in equation (15). The dispersion R here is R = 0.99.

As is clear from comparison between FIG. 15 and FIG. 16 , the evaluation value CAVIβm according to the equation (15) is much more stable than the conventionally proposed evaluation value CAVI (equation (14)).

It is a schematic diagram which shows an example of the pulse wave velocity measuring method. It is a schematic diagram which shows an example of the pulse wave velocity measuring method. It is a graph which shows the relationship between minimum blood pressure (diastolic blood pressure) and aortic pulse wave velocity. It is the figure which showed the pulse wave velocity correction curve. It is a block diagram which shows one Embodiment of the vascular sclerosis degree evaluation apparatus of this invention. It is a block diagram which shows one Embodiment of the vascular sclerosis degree calculation apparatus of this invention. 1 is an external view of a computer that operates as an embodiment of a vascular sclerosis calculation apparatus according to the present invention. It is a hardware block diagram of the computer which has the external appearance shown in FIG. It is a notional block diagram of the vascular sclerosis degree calculation program memorize | stored in CDROM. It is the figure which connected the evaluation value (beta) of the 2nd time of the patient of an artificial dialysis same as the evaluation value (beta) in the 1st test | inspection of the patient of artificial dialysis by connecting for each patient with the straight line. It is the figure which connected the evaluation value CAVI of the 2nd time of the patient of artificial dialysis same as the evaluation value CAVI in the 1st test | inspection of the patient of artificial dialysis for each patient connected with the straight line. The horizontal axis represents the evaluation value β in the first examination of an artificial dialysis patient whose expression is the same as the data shown in FIG. 10, and the evaluation value β in the second examination of the same artificial dialysis patient is It is the figure which showed the regression line while plotting the evaluation value (beta) for every patient on the vertical axis | shaft. The horizontal axis represents the evaluation value CAVI in the first examination of the dialysis patient whose expression is the same as the data shown in FIG. 11, and the evaluation value CAVI in the second examination of the same dialysis patient is It is the figure which plotted the regression line while plotting the evaluation value CAVI for every patient on the vertical axis | shaft. It is a figure which shows the correspondence of pulse wave velocity and evaluation value (beta) calculated | required by Formula (9). It is a figure which shows the correspondence of the pulse wave velocity and the evaluation value CAVI calculated | required by Formula (12). It is a figure which shows the correspondence of pulse wave velocity and evaluation value CAVI (beta) m calculated | required by Formula (13).

Explanation of symbols

10 Computer 11 Body 12 Display 13 Keyboard 14 Mouse 20 CDROM
DESCRIPTION OF SYMBOLS 100 Vascular sclerosis evaluation apparatus 101 Pulse wave velocity measurement part 102 Blood pressure measurement part 103 Evaluation value calculation part 104 Evaluation value output part 200 Vascular sclerosis degree calculation apparatus 201 Data acquisition part 202 Evaluation value calculation part 203 Evaluation value output part 300 Vascular sclerosis degree Calculation program 301 Data acquisition unit 302 Evaluation value calculation unit 303 Evaluation value output unit

Claims (9)

A pulse wave velocity measuring unit for obtaining the pulse wave velocity PWV;
A blood pressure measurement unit for obtaining a blood pressure composed of systolic blood pressure Ps and diastolic blood pressure Pd;
Using the pulse wave velocity obtained by the pulse wave velocity measurement unit and the blood pressure obtained by the blood pressure measurement unit,
Ln (Ps / Pd) · PWV ² / ΔP
Ln is a natural logarithm with e as the base.
ΔP = Ps−Pd
It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including:
An evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit ,
As the evaluation value β, the evaluation value calculation unit
β = 2ρ · Ln (Ps / Pd) · PWV ² / ΔP
Where ρ is the blood density.
A blood vessel sclerosis evaluation apparatus, characterized in that   Data representing the pulse wave velocity PWV or data for calculating the pulse wave velocity;
  A data acquisition unit for acquiring data representing blood pressure composed of systolic blood pressure Ps and diastolic blood pressure Pd or data for blood pressure calculation;
  Using the data acquired by the data acquisition unit,
      Ln (Ps / Pd) · PWV ² / ΔP
          Ln is a natural logarithm with e as the base.
                ΔP = Ps−Pd
          It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including:
  An evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit,
  As the evaluation value β, the evaluation value calculation unit
      β = 2ρ · Ln (Ps / Pd) · PWV ² / ΔP
          Where ρ is the blood density.
An apparatus for calculating the degree of vascular sclerosis, characterized in that   It is executed in an arithmetic processing unit that executes a program, and the arithmetic processing unit is
  Data representing the pulse wave velocity PWV or data for calculating the pulse wave velocity;
  A data acquisition unit for acquiring data representing blood pressure composed of systolic blood pressure Ps and diastolic blood pressure Pd or data for blood pressure calculation;
  Using the data acquired by the data acquisition unit,
      Ln (Ps / Pd) · PWV ² / ΔP
          Ln is a natural logarithm with e as the base.
                ΔP = Ps−Pd
          It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including:
  A blood vessel sclerosis degree calculation program that operates as a vascular sclerosis degree calculation device including an evaluation value output unit that outputs an evaluation value calculated by the evaluation value calculation unit,
  As the evaluation value β, the evaluation value calculation unit
      β = 2ρ · Ln (Ps / Pd) · PWV ² / ΔP
          Where ρ is the blood density.
A blood vessel sclerosis degree calculation program, characterized in that   A pulse wave velocity measuring unit for obtaining the pulse wave velocity PWV;
  A blood pressure measurement unit for obtaining a blood pressure comprising the average blood pressure Pm and the diastolic blood pressure Pd;
  Using the pulse wave velocity obtained by the pulse wave velocity measurement unit and the blood pressure obtained by the blood pressure measurement unit,
      Ln (Pm / Pd) · PWV ² / ΔP
          Ln is a natural logarithm with e as the base.
                ΔP = Pm−Pd
          It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including:
  An evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit,
  As the evaluation value β, the evaluation value calculation unit
      β = 2ρ · Ln (Pm / Pd) · PWV ² / ΔP
          Where ρ is the blood density.
A blood vessel sclerosis evaluation apparatus, characterized in that   5. The vascular sclerosis evaluation apparatus according to claim 4, wherein the blood pressure measurement unit obtains the blood pressure at the highest point of the pulse group when the oscillometric method is adopted as the average blood pressure Pm.   Data representing the pulse wave velocity PWV or data for calculating the pulse wave velocity;
  A data acquisition unit for acquiring data representing blood pressure including average blood pressure Pm and diastolic blood pressure Pd or data for blood pressure calculation;
  Using the data acquired by the data acquisition unit,
      Ln (Pm / Pd) · PWV ² / ΔP
          Ln is a natural logarithm with e as the base.
                ΔP = Pm−Pd
          It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including:
  An evaluation value output unit that outputs the evaluation value calculated by the evaluation value calculation unit,
  As the evaluation value β, the evaluation value calculation unit
      β = 2ρ · Ln (Pm / Pd) · PWV ² / ΔP
          Where ρ is the blood density.
An apparatus for calculating the degree of vascular sclerosis, characterized in that   As the data representing the average blood pressure Pm or the data for calculating the average blood pressure Pm, the data acquisition unit represents data representing the maximum blood pressure of the pulsation when the oscillometric method is employed, or data for calculating the blood pressure of the maximum point. The vascular sclerosis degree calculation apparatus according to claim 6, wherein:   It is executed in an arithmetic processing unit that executes a program, and the arithmetic processing unit is
  Data representing the pulse wave velocity PWV or data for calculating the pulse wave velocity;
  A data acquisition unit for acquiring data representing blood pressure including average blood pressure Pm and diastolic blood pressure Pd or data for blood pressure calculation;
  Using the data acquired by the data acquisition unit,
      Ln (Pm / Pd) · PWV ² / ΔP
          Ln is a natural logarithm with e as the base.
                ΔP = Pm−Pd
          It is.
An evaluation value calculation unit that calculates an evaluation value that indicates the degree of sclerosis of the blood vessel based on an arithmetic expression including:
  A blood vessel sclerosis degree calculation program that operates as a vascular sclerosis degree calculation device including an evaluation value output unit that outputs an evaluation value calculated by the evaluation value calculation unit,
  As the evaluation value β, the evaluation value calculation unit
      β = 2ρ · Ln (Pm / Pd) · PWV ² / ΔP
          Where ρ is the blood density.
A blood vessel sclerosis degree calculation program, characterized in that     As the data representing the average blood pressure Pm or the data for calculating the average blood pressure Pm, the data acquisition unit represents data representing the maximum blood pressure of the pulsation when the oscillometric method is employed, or data for calculating the blood pressure of the maximum point. The vascular sclerosis degree calculation program according to claim 8, wherein:

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