Vascular endothelial cell function evaluating apparatus

• US 6,719,704 B2
• Filed: 01/28/2003
• Issued: 04/13/2004
• Est. Priority Date: 05/14/2002
• Status: Expired due to Fees

• Current Assignee: Omron Healthcare Company Limited (Omron Corporation)
• Original Assignee: Colin Corporation (Fukuda Denshi Company Limited)
• Inventors: Ogura, Toshihiko, Narimatsu, Kiyoyuki, Tampo, Akira
• Primary Examiner(s): Winakur, Eric F.
• Assistant Examiner(s): Veniaminov, Nikita R
• Application Number:
  US10/352,175
• Publication Number:
  US 20030216652A1
• Time in Patent Office: 441 Days
• Field of Search: 600/300, 600/500, 600/483, 600/485, 600/492, 600/504, 600/490, 600/585, 600/561, 600/503, 600/502, 128/900, 514/12, 530/350, 482/8, 482/1, 482/9, 482/900, 737/27, 731/54, 731/56, 73D/IG.4
• US Class Current: 600/500
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/02225 using the oscillometric method
• CPC Class Codes: A61B 5/0255 Recording instruments specially adapted therefor
• CPC Class Codes: A61B 5/7239 using differentiation including higher order derivatives

Abstract

A vascular-endothelial-cell-function evaluating apparatus including a pressing device including a cuff that is adapted to be worn on a first portion of a living subject, and a cuff-pressure changing device that changes a pressure in the cuff so as to press the first portion of the subject in a pressing period, a pulse-wave detecting device that detects a pulse wave including a plurality of heartbeat-synchronous pulses, from the first portion of the subject, or a second portion of the subject located on a distal side of the first portion, and a pulse-wave-second-half-information obtaining device that obtains a plurality of sets of pulse-wave-second-half information that represent respective characteristics of respective second-half portions of respective heartbeat-synchronous pulses of the pulse wave that are detected by the pulse-wave detecting device at respective different times, the respective second-half portions of the respective heartbeat-synchronous pulses being respective portions of the respective pulses that are subsequent to respective peak points of the respective pulses, the pulse-wave-second-half-information obtaining device providing a time-wise change of the sets of pulse-wave-second-half information that is caused by the pressing of the pressing device.

Claims

1. A vascular-endothelial-cell-function evaluating apparatus comprising:

a pressing device including a cuff that is adapted to be worn on a first portion of a living subject, and a cuff-pressure changing device that changes a pressure in the cuff so as to press the first portion of the subject in a pressing period;

a pulse-wave detecting device that detects a pulse wave including a plurality of heartbeat-synchronous pulses, from the first portion of the subject, or a second portion of the subject located on a distal side of the first portion; and

a pulse-wave-second-half-information obtaining device that obtains a plurality of sets of pulse-wave-second-half information that represent respective characteristics of respective second-half portions of respective heartbeat-synchronous pulses of the pulse wave that are detected by the pulse-wave detecting device at respective different times, the respective second-half portions of the respective heartbeat-synchronous pulses being respective portions of the respective pulses that are subsequent to respective peak points of the respective pulses, the pulse-wave-second-half-information obtaining device providing a time-wise change of the sets of pulse-wave-second-half information that is caused by the pressing of the pressing device.

2. A vascular-endothelial-cell-function evaluating apparatus according to claim 1, wherein the pressing device presses, with the cuff, the first portion of the subject so as to stop a flow of blood in the first portion, and subsequently decreases the pressure of the cuff down to a pressure not higher than a mean blood pressure of the first portion, and

wherein the pulse-wave-second-half-information obtaining device obtains the sets of pulse-wave-second-half information in a waveform-deformation period in which the pressure of the cuff has already been decreased to the pressure not higher than the mean blood pressure of the first portion and respective waveforms of the respective heartbeat-synchronous pulses of the pulse wave are deformed yet as a result of the pressing of the pressing device.

3. A vascular-endothelial-cell-function evaluating apparatus according to claim 1, wherein the cuff-pressure changing device of the pressing device includes a blood-flow stopping device for increasing the pressure of the cuff up to a pressure higher than a systolic blood pressure of the first portion of the subject, so as to stop a flow of blood in the first portion;

a first pulse-wave-detection-pressure keeping device for keeping, before the blood-flow stopping device increases the pressure of the cuff, the pressure of the cuff at a pulse-wave detection pressure not higher than a mean blood pressure of the first portion, for a time duration corresponding to at least one heartbeat of the subject; and

a second pulse-wave-detection-pressure keeping device for keeping, after the blood-flow stopping device increases the pressure of the cuff, the pressure of the cuff at a pulse-wave detection pressure not higher than a mean blood pressure of the first portion, for a time duration corresponding to at least one heartbeat of the subject,

wherein the pulse-wave detecting device detects a cuff pulse wave that is transmitted from the first portion of the subject to the cuff, and

wherein the pulse-wave-second-half-information obtaining device obtains one of the sets of pulse-wave-second-half information from a cuff pulse wave detected by the pulse-wave detecting device in a state in which the pressure of the cuff is kept at the pulse-wave detection pressure by the first pulse-wave-detection-pressure keeping device, and obtains the other set of pulse-wave-second-half information from a cuff pulse wave detected by the pulse-wave detecting device in a state in which the pressure of the cuff is kept at the pulse-wave detection pressure by the second pulse-wave-detection-pressure keeping device.

4. A vascular-endothelial-cell-function evaluating apparatus according to claim 3, wherein the cuff-pressure changing device of the pressing device further includes a pressure increasing device for increasing, before the first pulse-wave-detection-pressure keeping device keeps the pressure of the cuff at the pulse-wave detection pressure, the pressure of the cuff from a pressure lower than a diastolic blood pressure of the first portion of the subject, and

wherein the apparatus further comprises a pulse-wave-detection-pressure determining device for determining the pulse-wave detection pressure based on a fact that a deformation occurs to a waveform of a heartbeat-synchronous pulse of the cuff pulse wave continuously detected by the pulse-wave detecting device while the pressure of the cuff is increased by the pressure increasing device.

5. A vascular-endothelial-cell-function evaluating apparatus according to claim 3, wherein the cuff-pressure changing device of the pressing device further includes a preliminary pressing device for increasing, before the first pulse-wave-detection-pressure keeping device keeps the pressure of the cuff at the pulse-wave detection pressure, the pressure of the cuff up to the pulse-wave detection pressure, by a predetermined number of times, so as to preliminarily press the first portion of the subject.

6. A vascular-endothelial-cell-function evaluating apparatus according to claim 5, wherein the cuff-pressure changing device of the pressing device further includes a pressure increasing device for increasing, before the preliminary pressing device increases the pressure of the cuff, the pressure of the cuff from a pressure lower than a diastolic blood pressure of the first portion of the subject, and

wherein the apparatus further comprises a pulse-wave-detection-pressure determining device for determining the pulse-wave detection pressure based on a fact that a deformation occurs to a waveform of a heartbeat-synchronous pulse of the cuff pulse wave continuously detected by the pulse-wave detecting device while the pressure of the cuff is increased by the pressure increasing device.

7. A vascular-endothelial-cell-function evaluating apparatus according to claim 3, wherein the blood-flow stopping device comprises a blood-pressure-measurement-related pressure changing device for increasing the pressure of the cuff up to the pressure higher than the systolic blood pressure of the first portion of the subject, and subsequently decreasing the pressure of the cuff, and

wherein the apparatus further comprises a blood-pressure determining device for determining a blood pressure of the subject based on a cuff pulse wave detected by the pulse-wave detecting device while the pressure of the cuff is decreased by the blood-pressure-measurement-related pressure changing device.

8. A vascular-endothelial-cell-function evaluating apparatus according to claim 1, wherein each of the sets of pulse-wave-second-half information comprises an augmentation index indicating a proportion of a reflected-wave component of the pulse wave to an incident-wave component thereof.

9. A vascular-endothelial-cell-function evaluating apparatus according to claim 1, wherein each of the sets of pulse-wave-second-half information comprises a degree of sharpness of the pulse wave.

10. A vascular-endothelial-cell-function evaluating apparatus according to claim 1, wherein each of the sets of pulse-wave-second-half information comprises a diastolic area of the pulse wave.

11. A vascular-endothelial-cell-function evaluating apparatus according to claim 1, further comprising a heart-rate-related-information obtaining device that obtains a plurality of sets of heart-rate-related information each of which is related to a heart rate of the subject, based on respective heartbeat-synchronous pulses of the pulse wave that are detected by the pulse-wave detecting device at respective different times, the heart-rate-related-information obtaining device providing a time-wise change of the sets of heart-rate-related information that is caused by the pressing of the pressing device.

12. A vascular-endothelial-cell-function evaluating apparatus according to claim 1, wherein the pulse-wave-second-half-information obtaining device comprises a display device that displays the plurality of sets of pulse-wave-second-half information, and thereby provides the time-wise change of the sets of pulse-wave-second-half information that is caused by the pressing of the pressing device.