Arteriosclerosis evaluating apparatus

• US 6,666,827 B2
• Filed: 07/15/2002
• Issued: 12/23/2003
• Est. Priority Date: 12/25/2001
• Status: Expired due to Fees

• Current Assignee: Omron Healthcare Company Limited (Omron Corporation)
• Original Assignee: Colin Corporation (Fukuda Denshi Company Limited)
• Inventors: Narimatsu, Kiyoyuki
• Primary Examiner(s): Hindenburg, Max F.
• Assistant Examiner(s): Natnithithadha, Navin
• Application Number:
  US10/193,986
• Publication Number:
  US 20030120158A1
• Time in Patent Office: 526 Days
• Field of Search: 600/490, 600/481, 600/483, 600/485, 600/492, 600/493, 600/494, 600/495, 600/496, 600/500, 600/501, 600/502
• US Class Current: 600/490
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/0285 Measuring or recording phase velocity of blood waves

Abstract

An apparatus for evaluating arteriosclerosis of a living subject, including a pulse-wave detecting device which detects a pulse wave from each of a first portion and a second portion of the subject, each of the respective pulse waves detected from the first and second portions containing an incident-wave component, an augmentation-index determining device for determining, based on the pulse wave detected from the first portion by the pulse-wave detecting device, a first augmentation index indicative of a degree of augmentation of an amplitude of the pulse wave detected from the first portion, from an amplitude of the incident-wave component of the pulse wave detected from the first portion, and determining, based on the pulse wave detected from the second portion by the pulse-wave detecting device, a second augmentation index indicative of a degree of augmentation of an amplitude of the pulse wave detected from the second portion, from an amplitude of the incident-wave component of the pulse wave detected from the second portion, and an arteriosclerosis evaluating device for evaluating the arteriosclerosis of the subject, based on a comparison of the first and second augmentation indexes determined by the augmentation-index determining device.

Claims

1. An apparatus for evaluating arteriosclerosis of a living subject, comprising:

a pulse-wave detecting device which detects a pulse wave from each of a first portion and a second portion of the subject, each of the respective pulse waves detected from the first and second portions containing an incident-wave component;

an augmentation-index determining means for determining, based on the pulse wave detected from the first portion by the pulse-wave detecting device, a first augmentation index indicative of a degree of augmentation of an amplitude of the pulse wave detected from the first portion, from an amplitude of the incident-wave component of the pulse wave detected from the first portion, and determining, based on the pulse wave detected from the second portion by the pulse-wave detecting device, a second augmentation index indicative of a degree of augmentation of an amplitude of the pulse wave detected from the second portion, from an amplitude of the incident-wave component of the pulse wave detected from the second portion; and

an arteriosclerosis evaluating means for evaluating the arteriosclerosis of the subject, based on a comparison of the first and second augmentation indexes determined by the augmentation-index determining means.

2. An apparatus according to claim 1, further comprising a comparison-value calculating means for calculating a comparison value as the comparison of the first and second augmentation indexes determined by the augmentation-index determining means,

wherein the arteriosclerosis evaluating means evaluates the arteriosclerosis of the subject, based on the comparison value calculated by the comparison-value calculating means and at least one of the first and second augmentation indexes determined by the augmentation-index determining means.

3. An apparatus according to claim 1, further comprising:

a comparison-value calculating means for calculating a comparison value as the comparison of the first and second augmentation indexes determined by the augmentation-index determining means; and

a pulse-wave-propagation-velocity-related-information obtaining device which obtains pulse-wave-propagation-velocity-related information that is related to a velocity at which the pulse wave propagates in the subject,

wherein the arteriosclerosis evaluating means evaluates the arteriosclerosis of the subject, based on the comparison value calculated by the comparison-value calculating means and the pulse-wave-propagation-velocity-related information obtained by the pulse-wave-propagation-velocity-related-information obtaining device.

4. An apparatus according to claim 1, further comprising:

a comparison-value calculating means for calculating a comparison value as the comparison of the first and second augmentation indexes determined by the augmentation-index determining means; and

a pulse-pressure determining means for determining a pulse pressure of at least one of the respective pulse waves detected from the first and second portions by the pulse-wave detecting device,

wherein the arteriosclerosis evaluating means evaluates the arteriosclerosis of the subject, based on the comparison value calculated by the comparison-value calculating means and the pulse pressure determined by the pulse-pressure determining means.

5. An apparatus according to claim 1, wherein the augmentation-index determining means determines, based on the pulse wave detected as a first pulse wave from the first portion by the pulse-wave detecting device, the first augmentation index, AIc, equal to a percentage of a difference, Δ

Pc, of a pulse pressure, PPc, of the first pulse wave from a pulse pressure PPci of the incident-wave component of the first pulse wave, relative to the pulse pressure PPc of the first pulse wave, according to a following expression;

AIc=(Δ

Pc/PPc)×

100, and determines, based on the pulse wave detected as a second pulse wave from the second portion by the pulse-wave detecting device, the second augmentation index, AIb, equal to a percentage of a difference, Δ

Pb, of a pulse pressure, PPb, of the second pulse wave from a pulse pressure PPbi of the incident-wave component of the second pulse wave, relative to the pulse pressure PPb of the second pulse wave, according to a following expression;

AIb=(Δ

Pb/PPb)×

100.

6. An apparatus according to claim 5, further comprising a comparison-value calculating means for calculating, as the comparison of the first and second augmentation indexes AIc, AIb determined by the augmentation-index determining means, a comparison value selected from the group consisting of a ratio, R, of one of the first and second indexes AIc, AIb to the other index;

a difference, d, of one of the first and second indexes AIc, AIb from the other index; and

a value obtained by dividing the difference d by the ratio R.

7. An apparatus according to claim 3, wherein the pulse-wave detecting device comprises:

a pressure-pulse-wave sensor which is adapted to be pressed against an artery of the first portion of the subject to detect, from the first portion, a pressure pulse wave produced from the artery; and

an inflatable cuff which is adapted to be worn on the second portion of the subject to detect, from the second portion, a cuff pulse wave.

8. An apparatus according to claim 7, wherein the pulse-wave-propagation-velocity-related-information obtaining device comprises time-difference determining means for determining, as the pulse-wave-propagation-velocity-related information, a time difference between a time of occurrence of a prescribed point of a heartbeat-synchronous pulse of the pressure pulse wave detected by the pressure-pulse-wave sensor and a time of occurrence of a prescribed point of a corresponding heartbeat-synchronous pulse of the cuff pulse wave detected by the cuff.

9. An apparatus according to claim 8, wherein the pulse-wave-propagation-velocity-related-information obtaining device further comprises:

a propagation-distance determining means for determining a propagation distance equal to a difference of a first distance between the first portion, and a heart, of the subject and a second distance between the second portion, and the heart, of the subject; and

a velocity determining means for determining, as the pulse-wave-propagation-velocity-related information, the velocity based on the time difference determined by the time-difference determining means and the propagation distance determined by the propagation-distance determining means.

10. An apparatus for evaluating arteriosclerosis of a living subject, comprising:

a pulse-wave detecting device which detects a pulse wave from each of a first portion and a second portion of the subject, each of the respective pulse waves detected from the first and second portions containing an incident-wave component;

an augmentation-index determining means for determining, based on the pulse wave detected from the first portion by the pulse-wave detecting device, a first augmentation index indicative of a degree of augmentation of an amplitude of the pulse wave detected from the first portion, from an amplitude of the incident-wave component of the pulse wave detected from the first portion, and determining, based on the pulse wave detected from the second portion by the pulse-wave detecting device, a second augmentation index indicative of a degree of augmentation of an amplitude of the pulse wave detected from the second portion, from an amplitude of the incident-wave component of the pulse wave detected from the second portion; and

a display device which displays the first and second augmentation indexes determined by the augmentation-index determining means.