GB2291505A - Apparatus for monitoring the electrical activity of a heart - Google Patents
Apparatus for monitoring the electrical activity of a heart Download PDFInfo
- Publication number
- GB2291505A GB2291505A GB9514555A GB9514555A GB2291505A GB 2291505 A GB2291505 A GB 2291505A GB 9514555 A GB9514555 A GB 9514555A GB 9514555 A GB9514555 A GB 9514555A GB 2291505 A GB2291505 A GB 2291505A
- Authority
- GB
- United Kingdom
- Prior art keywords
- support means
- electrically conducting
- heart
- chest
- contact
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/68—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient
- A61B5/6801—Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be attached to or worn on the body surface
- A61B5/683—Means for maintaining contact with the body
- A61B5/6831—Straps, bands or harnesses
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/25—Bioelectric electrodes therefor
- A61B5/279—Bioelectric electrodes therefor specially adapted for particular uses
- A61B5/28—Bioelectric electrodes therefor specially adapted for particular uses for electrocardiography [ECG]
- A61B5/282—Holders for multiple electrodes
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Medical Informatics (AREA)
- Biophysics (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Physics & Mathematics (AREA)
- Molecular Biology (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Cardiology (AREA)
- Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)
Abstract
Apparatus 10 for monitoring the electrical activity of a heart in a living human or animal body 15 comprising a chest-worn contractible support means 1, electrically conducting contact means 2 attached to or forming part of the support means which are brought to bear against the surface of the skin of the chest by contraction of the support means to pick up electrical signals generated by the heart of the body, an electrocardiogram display and/or recording unit 7, and electrical connection means 6 for electrically connecting the contact means to the unit to produce from the heart generated electrical signals picked up by the contact means from the skin surface an electrocardiogram display and/or record of the electrical activity of the heart. <IMAGE>
Description
Apparatus for Monitoring the
Electrical Activity of a Heart
The present invention relates to apparatus for monitoring the electrical activity of a heart in a living human or animal body in which signals arising from the electrical activity of the heart are picked up from a surface of the skin of the chest of the body and conducted to an electrocardiogram display and/or recording unit which displays and/or records the heart-generated electrical signals. The displays or records of these signals are commonly called electrocardiograms (ECGs).
Hitherto, it has been common practice when taking electrocardiograms of the heart in a living human or animal body to pick up heart-generated electrical signals from the skin at multiple sites on the chest and limbs of the body by means of contacts which are applied to the skin by individual self-adhesive patches specially manufactured for this purpose or by individual contact means held in place against the skin by suction.
It has been found, however, that careful preparation of the skin is often required at the point of contact of the self-adhesive patches or contact means against the skin.
This may involve shaving to remove chest hair, cleansing to remove body oils, and the application of conducting gel. Furthermore, positioning of individual contact means almost always requires medical supervision so that the correct electrical signals from the heart are conveyed to the display/recording unit.
In addition to the above, the prior self-adhesive patch proposal suffers from the following further drawbacks: (i) when electrocardiograms are recorded
by ambulatory monitors for periods of
the order of twenty-four hours, the
subject is rarely able to wash
thoroughly for fear of removing the
self-adhesive patches, (ii) the self-adhesive patches can be used
once only and a constant supply is
therefore essential to the taking of
electrocardiograms, and (iii) the cost of the patches is not
negligible and therefore the taking
of electrocardiograms in the remoter
and poorer parts of the world is not
easy.
The taking of a single-channel electrocardiogram has hitherto normally required the use of a minimum of three contacts, two primary contacts to drive the inputs of a differential amplifier and a third contact to provide an "earth" point. The typical amplitude of an electrical signal generated by the heart is only about lmV and such a small signal is prone to contamination by extraneous electrical signals, the most common source of which is from neighbouring electrical apparatus or wiring. This interference is minimised by earth shielding the wires typically used for connecting the contacts on the chest to the amplifier, and by ensuring that the contact impedances at each connection point on the chest are small and identical.Another source of electrical interference is due to the electrical noise generated by fluctuations in the electro-chemical potential developed across the skin/contact interface.
The electrical activity of a heart of a living human or animal can be "viewed" from different directions by selecting different points on the body where electrical contact is made. These various "views" produce electrical signals of very different shape and convey to a trained observer different diagnostic information about the condition of the heart.
It will be gathered from the foregoing that there is a need for a reusable device which can make electrical contact with the skin at multiple sites on the chest of a human or animal body for the purpose of generating an electrocardiogram, is removable and holds electrically conducting contacts in the appropriate relative positions against the surface of the skin of the body for picking up the desired electrical signals of the heart. Such a device could then be fitted by non-skilled personnel, and would be removable so that the user could enjoy full bathing. In addition, it would also be useful if a contact material were used which exhibits only small random fluctuations in the electro-chemical potential to reduce electrical interference generated by fluctuations in the electro-chemical potential developed across the skin/conducting contact interface.
According to the present invention there is provided an apparatus for monitoring the electrical activity of a heart in a living human or animal body comprising chestworn contractible support means having an operational disposition in which the support means is worn on the chest of the body, electrically conducting contact means attached to or forming part of the support means and which in the operational disposition of the support means are brought to bear against the surface of the skin of the chest by contraction of the support means to pick up electrical signals generated by the heart of the body, an electrocardiogram display and/or recording unit, and electrical connection means for electrically connecting the contact means to the unit to produce from the heartgenerated electrical signals picked up by the contact means from the skin surface an electrocardiogram display and/or record of the electrical activity of the heart.
In a preferred embodiment of the invention the electrically conducting contact means are made from an electrically conducting rubber.
In an embodiment of the invention hereinafter to be described the electrically conducting contact means are slidable with respect to the support means to allow relative movement between the contact means and the support means to bring the contact means to bear against a predetermined disposition on the chest in the operational disposition of the support means.
Conveniently, the electrically conducting contact means are mounted on a sliding collar which is attached to or forms part of the support means.
In an embodiment of the invention the electrically conducting contact means comprises two electrically conducting contacts spaced apart on the support means.
The electrically conducting contact means may, however, comprise more than two electrically conducting contacts spaced apart on the support means.
In an embodiment of the invention hereinafter to be described each electrically conducting contact has a sheet resistance of less than 500 ohms per square with 100 ohms per square being preferred.
In an embodiment of the invention hereinafter to be described the support means in the operational disposition extends fully round the chest. The support means may include an elasticated section which in the operational disposition imposes a contracting force in the support means to bring the contact means to bear against the surface of the skin of the chest.
In an embodiment of the invention the support means is adjustable in length by means of a buckle.
In embodiments of the invention hereinafter to be described the support means takes the form of a belt. In an alternative embodiment the support means takes the form of a harness.
In an embodiment of the invention hereinafter to be described the electrical connection means comprises flexible metal wire or conducting rubber.
According to the present invention there is also provided a sensor structure for sensing the electrical activity of the heart in a living human or animal body comprising chest-worn contractible support means having an operational disposition in which the support means is worn on the chest of the body and electrically conducting contact means attached to or forming part of the support means and which in the operational disposition of the support means are brought to bear against the surface of the skin of the chest by contraction of the support means to pick up electrical signals generated by the heart of the body, the electrically conducting contact means being adapted for connection to an electrocardiogram display and/or recording unit to generate an electrocardiogram display and/or record of the electrical activity of the heart of the body.
According to the present invention there is yet further provided use of chest-worn contractible support means having electrically conducting contact means fixed thereto or forming part thereof for picking up the electrical signals generated by the heart in a living human or animal body in taking an electrocardiogram of the heart.
Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:
Figure 1 is a schematic diagram illustrating a user and an apparatus for monitoring the electrical activity of the user's heart according to the present invention which incorporates a chest-worn belt;
Figure 2 is a schematic plan view of the front portion of the belt as worn in Figure 1;
Figure 3 is a schematic front view of an alternative chest-worn belt in accordance with the present invention having two electrically conducting contacts slidable with respect to the belt; and
Figure 4 is a schematic plan view of the front portion of the belt depicted in Figure 3.
Referring to Figures 1 and 2, there is shown an apparatus 10 for monitoring the electrical activity of the heart of a user 15 according to the present invention. The apparatus 10 comprises chest-worn contractible support means 1 in the form of a chest-worn belt which encircles the chest of the user 15 and which can be adjusted in length to suit the girth of the user 15, for example by means of a buckle in standard fashion. An elasticated section is incorporated in the belt 1 and imposes a contracting force on the belt 1 to bring two electrically conducting rubber contacts 2 fixed on the inside of the belt 1 to bear against the surface of the skin of the chest of the user 15. The contacts 2 have a sheet resistance of less than 500 ohms per square and preferably have a sheet resistance of 100 ohms per square.
Each electrically conducting contact 2 has an electrical connector 3 which protrudes to the front of the belt 1 for coupling to electrically conducting leads 6 which connect the contacts 2 on the belt 1 to an electrocardiogram display/recording apparatus 7. The leads 6 provide electrical connection by the use of flexible metal wires or conducting rubber. The belt 1 is positioned around the chest so that the conducting contacts 2 are positioned just below the nipples of the user 15. Electrical signals from the heart of the user 15 are thus able to be picked up by the electrically conducting contacts 2 on the belt 1 and sent via the connecting leads 6 to the ECG display/recording apparatus 7 for display of the electrical activity of the heart in the form of an electrocardiogram.
The fixed nature of the contacts 2 on the belt 1 enables the user 15 to remove and reapply the belt 1 to the position where the contacts 2 can again pick up the electrical signals from the heart.
Referring now to Figures 3 and 4, there is shown an alternative chest-worn belt 11 in accordance with the present invention and which is appropriate when either different electrical "views" of the heart's activity are required or when a user's chest is significantly smaller or larger than average.
The supporting belt 11 is similar to that illustrated in
Figures 1 and 2, again having a pair of electrically conducting rubber contacts 12 on the inside of the belt 11 with each contact 12 having a sheet resistance of less than 500 ohms per square and an electrical connector 13 which protrudes to the front of the belt 11 for electrical coupling to an electrocardiogram display/recording apparatus (not shown). The electrically conducting contacts 12 in the alternative chest-worn belt 11, though, are mounted on sliding collars 4 which allow the contacts 12 to be moved along the belt 11 until the correct sites are located for picking up the heart-generated electrical signals from the surface of the skin of the chest. The belt 11 cannot, however, conveniently cover the whole body and therefore not all of the standard "views" (for example those involving limb connection) are possible.
While the positions of the electrically conducting contacts 12 may need to be located initially by trained medical personnel, medical personnel would not need to be involved in any subsequent removal and reapplication of the chest-worn belt device 11 for a given user.
In the embodiments of the invention hereinabove described with reference to the accompanying Figures of drawings, the contacts 2 and 12 are preferably made of electrically conducting rubber of such composition that the only preparation of the skin required is the application of water or saline solution to the area of contact. In this instance, the present invention has the advantage that means are provided for making an electrical contact with the skin surface of the chest to produce an electrocardiogram without the necessity of elaborate preparation of the skin at the sites of electrical contact with the skin. Users with particularly hirsute bodies may, however, require shaving at the sites of contact on the chest.
It should be noted that the present invention is not limited to the use of chest-worn support means in the form of belts such as those described hereinabove with reference to the accompanying Figures of drawings. Any other chest-worn support means which is contractible, for example a chest-worn harness, would be equally suitable.
The reusability of the chest-worn support means in accordance with the invention is clearly useful in that it allows a user to wash or bathe when electrocardiograms are required to be generated over extended periods of time.
As stated hereinbefore, it has hitherto been necessary to provide a minimum of three electrically conducting contacts to allow satisfactory heart-generated electrical signals to be obtained from the surface of the chest of a human or animal. In accordance with the invention, however, conducting rubber contacts are advantageously used on the chest-worn support means which achieve such noise-free connection with the chest that an "earth" lead is not required. Where measurements have to be taken in particularly noisy electrical environments or where the skin of the user does not afford a low contact impedance, however, a third "earth" conducting contact can be incorporated at a suitable position on the chest-worn support means.
Claims (20)
1. Apparatus for monitoring the electrical activity of a heart in a living human or animal body comprising: (a) chest-worn contractible support means having an
operational disposition in which the support means
is worn on the chest of the body, (b) electrically conducting contact means attached to or
forming part of the support means and which in the
operational disposition of the support means are
brought to bear against the surface of the skin of
the chest by contraction of the support means to
pick up electrical signals generated by the heart of
the body, (c) an electrocardiogram display and/or recording unit,
and (d) electrical connection means for electrically
connecting the contact means to the unit to produce
from the heart generated electrical signals picked
up by the contact means from the skin surface an
electrocardiogram display and/or record of the
electrical activity of the heart.
2. Apparatus according to claim 1, wherein the electrically conducting contact means are made from electrically conducting rubber.
3. Apparatus according to claim 1 or 2, wherein the electrically conducting contact means are slidable with respect to the support means to allow relative movement between the contact means and the support means to bring the contact means to bear against a predetermined disposition on the chest in the operational disposition of the support means.
4. Apparatus according to claim 3, wherein the electrically conducting contact means are mounted on a sliding collar which is attached to or forms part of the support means.
5. Apparatus according to any of claims 1 to 4, wherein the electrically conducting contact means comprises two or more electrically conducting contacts spaced apart on the support means.
6. Apparatus according to claim 5, wherein the electrically conducting contact means comprises three electrically conducting contacts spaced apart on the support means.
7. Apparatus according to claim 5 or 6, wherein each electrically conducting contact has a sheet resistance of less than 500 ohms per square.
8. Apparatus according to claim 7, wherein each electrically conducting contact has a sheet resistance of 100 ohms per square or substantially 100 ohms per square.
9. Apparatus according to any of claims 1 to 8, wherein in the operational disposition the support means extends fully round the chest.
10. Apparatus according to any of claims 1 to 9, wherein the support means includes an elasticated section which in the operational disposition imposes the contracting force in the support means to bring the contact means to bear against the surface of the skin of the chest.
11. Apparatus according to any of claims 1 to 10, wherein the support means is adjustable in length by means of a buckle.
12. Apparatus according to any of claims 1 to 11, wherein the support means is in the form of a harness or belt.
13. Apparatus according to any of the preceding claims, wherein the electrical connection means comprises flexible metal wire or electrically conducting rubber.
14. A sensor structure for sensing the electrical activity of the heart in a living human or animal body comprising chest-worn contractible support means having an operational disposition in which the support means is worn on the chest of the body and electrically conducting contact means attached to or forming part of the support means and which in the operational disposition of the support means are brought to bear against the surface of the skin of the chest by contraction of the support means to pick up electrical signals generated by the heart of the body, the electrically conducting contact means being adapted for connection to an electrocardiogram display and/or recording unit to generate an electrocardiogram display and/or record of the electrical activity of the heart of the body.
15. Structure according to claim 14, wherein the electrically conducting contact means comprises two or more electrically conducting rubber contacts spaced apart on the support means with each electrically conducting rubber contact having a sheet resistance of less than 500 ohms per square.
16. Structure according to claim 15, wherein each electrically conducting rubber contact has a sheet resistance of 100 ohms per square or substantially 100 ohms per square.
17. Structure according to claim 15 or 16, wherein the electrically conducting rubber contacts are slidable with respect to the support means to allow relative movement between the contacts and the support means to bring the contacts to bear against a predetermined disposition on the chest in the operational disposition of the support means.
18. Use of chest-worn contractible support means having electrically conducting contact means fixed thereto or forming part thereof for picking up the electrical signals generated by the heart in a living human or animal body in taking an electrocardiogram of the heart.
19. Apparatus for monitoring the electrical activity of a heart in a living human or animal body substantially as hereinbefore described with reference to
Figures 1 and 2 or Figures 3 and 4 of the accompanying drawings.
20. A sensor structure for sensing the electrical activity of a heart in a living human or animal body substantially as hereinbefore described with reference to
Figures 1 and 2 or Figures 3 and 4 of the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9414569A GB9414569D0 (en) | 1994-07-19 | 1994-07-19 | Apparatus for monitoring the electrical activity of a heart |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9514555D0 GB9514555D0 (en) | 1995-09-13 |
| GB2291505A true GB2291505A (en) | 1996-01-24 |
| GB2291505B GB2291505B (en) | 1998-11-04 |
Family
ID=10758568
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9414569A Pending GB9414569D0 (en) | 1994-07-19 | 1994-07-19 | Apparatus for monitoring the electrical activity of a heart |
| GB9514555A Expired - Lifetime GB2291505B (en) | 1994-07-19 | 1995-07-17 | Apparatus for monitoring the electrical activity of a heart |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9414569A Pending GB9414569D0 (en) | 1994-07-19 | 1994-07-19 | Apparatus for monitoring the electrical activity of a heart |
Country Status (1)
| Country | Link |
|---|---|
| GB (2) | GB9414569D0 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2323038A (en) * | 1997-03-12 | 1998-09-16 | Laerdal Medical Ltd | Pad for holding ECG electrodes |
| EP0865762A2 (en) * | 1997-02-19 | 1998-09-23 | Joan Maria Dr. Pons Creus | Electrode support for cardiology |
| GB2350193A (en) * | 1999-03-15 | 2000-11-22 | Alan Remy Magill | Health monitoring garment |
| FR2908974A1 (en) * | 2006-11-24 | 2008-05-30 | Yves Faisandier | Electrocardiographic signal collecting device, has electrode covered with gel and free from adhesive, and base maintaining electrode fixed against skin and integrated to attachment that permits sliding and blocking of belt |
| EP2865327A1 (en) * | 2013-10-25 | 2015-04-29 | Seiko Instruments Inc. | Heart rate measuring device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3525330A (en) * | 1966-02-24 | 1970-08-25 | Lockheed Aircraft Corp | Surgical garment prescription method and apparatus |
| US3534727A (en) * | 1967-03-24 | 1970-10-20 | Nasa | Biomedical electrode arrangement |
| US4608987A (en) * | 1982-12-03 | 1986-09-02 | Physioventures, Inc. | Apparatus for transmitting ECG data |
-
1994
- 1994-07-19 GB GB9414569A patent/GB9414569D0/en active Pending
-
1995
- 1995-07-17 GB GB9514555A patent/GB2291505B/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3525330A (en) * | 1966-02-24 | 1970-08-25 | Lockheed Aircraft Corp | Surgical garment prescription method and apparatus |
| US3534727A (en) * | 1967-03-24 | 1970-10-20 | Nasa | Biomedical electrode arrangement |
| US4608987A (en) * | 1982-12-03 | 1986-09-02 | Physioventures, Inc. | Apparatus for transmitting ECG data |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0865762A2 (en) * | 1997-02-19 | 1998-09-23 | Joan Maria Dr. Pons Creus | Electrode support for cardiology |
| EP0865762A3 (en) * | 1997-02-19 | 1999-04-07 | Joan Maria Dr. Pons Creus | Electrode support for cardiology |
| ES2130062A1 (en) * | 1997-02-19 | 1999-06-16 | Pons Creus Joan Maria | Electrode support for cardiology |
| GB2323038A (en) * | 1997-03-12 | 1998-09-16 | Laerdal Medical Ltd | Pad for holding ECG electrodes |
| GB2350193A (en) * | 1999-03-15 | 2000-11-22 | Alan Remy Magill | Health monitoring garment |
| GB2350193B (en) * | 1999-03-15 | 2003-04-09 | Alan Remy Magill | Health monitoring garment |
| FR2908974A1 (en) * | 2006-11-24 | 2008-05-30 | Yves Faisandier | Electrocardiographic signal collecting device, has electrode covered with gel and free from adhesive, and base maintaining electrode fixed against skin and integrated to attachment that permits sliding and blocking of belt |
| EP2865327A1 (en) * | 2013-10-25 | 2015-04-29 | Seiko Instruments Inc. | Heart rate measuring device |
| US9131894B2 (en) | 2013-10-25 | 2015-09-15 | Seiko Instruments Inc. | Biological information detecting device |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2291505B (en) | 1998-11-04 |
| GB9414569D0 (en) | 1994-09-07 |
| GB9514555D0 (en) | 1995-09-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PE20 | Patent expired after termination of 20 years |
Expiry date: 20150716 |