SE546040C2

SE546040C2 - A wearable electrocardiogram device

Info

Publication number: SE546040C2
Application number: SE2250097A
Authority: SE
Inventors: Erik Rask
Original assignee: Medbeat Sweden Ab
Priority date: 2022-02-02
Filing date: 2022-02-02
Publication date: 2024-04-23
Also published as: SE2250097A1

Abstract

The invention relates to a wearable electrocardiogram device (2) comprising a patch (3) to be attached to the chest of a user (1) and a housing (4) which is attached to and carried by the patch when the device is in operation. The patch (3) is provided with an electrode (5) measuring signals from a heart. The housing (4) contains electronics (21) which processes such signals received from the electrode (5) and produces electrocardiogram data. The patch (3) is adjustable in different positions relative to the housing (4).

Description

TECHNICAL FIELD The invention relates to a wearable electrocardiogram device comprising a patch to be attached to the chest of a user and a housing which is attached to and carried by the patch When the device is in operation.

BACKGROUND Electrocardiogram (ECG) devices are used for recording the electrical activity of a heart. Signals from the heart are measured by electrodes arranged on the skin of a user and based on the signals from the heart, a graph showing voltage versus time of the electrical activity is created.

A lot of different cardiac abnormalities Will result in an ECG pattern that deviates from a normal ECG pattern. Such cardiac abnormalities are for example cardiac rhythm disturbances, inadequate coronary artery blood flow, electrolyte disturbances, etc.

Some cardiac problems cannot be detected by means of a standard ECG device used for measuring the electrical activity of the heart during a relatively short time period. Detection of abnormalities Which only occur briefly and unpredictably requires that the electrical activity of the heart is recorded continuously for a longer period and also when the user participates in normal daily activities.

For this reason, a wearable ECG device which can record the electrical activity of the heart for a prolonged time is often required in order to correctly diagnose the condition of a person. ln addition to be safe and comfortable to carry, it is important that such a wearable ECG device provides a reliable measurement of the relevant heart signals.

SUMMARY An objective of the invention is to provide a wearable electrocardiogram device, which ECG device can be used for varying body constitutions while still being capable of providing reliable measurement data.

The objective is achieved by a wearable electrocardiogram device according to claimThe invention is based on the insight that by such a device, the position of the electrode on the user can be varied for the same position of the housing. This in turn will facilitate the positioning of the electrode at an optimal measuring point at the same time as the housing can be positioned to make it safe and comfortable to carry the device. The optimal measuring point may vary due to the body constitution or the type of measurement to be performed. The electrode position can be adapted to the body size and proportions of the user. The adjustable electrode position allows for a larger variation of the shape of users and their hearts, while maintaining high signal-to-noise measurements. Further, in order to detect different cardiac problems, various electrode positions can be selected.

The distance between the electrode and the housing can be varied, for reaching a measurement point which otherwise would require another size of the patch. This will reduce the need of using a lot of patches in different sizes.

Further, different measurement points at the same distance from the housing can be reached with one and the same patch.

The housing can be attached to the patch in a non-complicated way such that the device constitutes a single unit to be worn by the user.

The patch, such as a strip or pad, is suitably provided with an adhesive for attaching the patch to the skin of a user of the device.

By “adjustable” is meant that the patch can be positioned or set to be situated in different positions relative to the housing. These positions can be reached by a mutual translational and/or pivot motion between the patch and the housing. lt is stressed that by “wearable” or ”portable” is meant a device that can be carried by the user as a single unit attached to the body by the patch without any use of a bag, pouch, harness, garment or similar. ln addition, there is no need of any cabling or electrical wiring extending between the device and any external unit for measuring and processing heart signals. Theelectrocardiogram data recorded by the device can however of course be transferred to another arrangement for further analysis or displaying of an electrocardiogram.

For example, when using a plurality of said patch, where each patch is provided with one said electrode, the positions of the electrodes can be highly varied when the patches are applied to a user, whereas the housing can be situated in the same position for different electrode patterns.

Preferably, at least one patch is individually adjustable in different positions relative to the housing and relative to the remaining of the plurality of said patch, and preferably a plurality or all patches are individually adjustable in different positions relative to the housing and relative to the other patches. Hereby, the mutual positions of the electrodes can be varied for achieving a lot of different electrode patterns.

The device preferably comprises three said patches each having one said electrode measuring signals from the heart, and a further electrode which is a reference electrode. The reference electrode can also be arranged in such a patch. ln this case, as an example, one useful type of measurement is performed with the electrodes receiving signals arranged on the chest of the user such that one electrode is arranged centrally on the sternum, another electrode is arranged on the left side of sternum in the interspace between the fourth rib and the fifth rib, or between the second rib and the third rib, and a further electrode is arranged on the right side of sternum in the interspace between the fourth rib and the fifth rib, or between the second rib and the third rib.

The coupling may comprise a snap button having a female portion and a male portion, and one of the female portion and the male portion is arranged on the patch and the other of the female portion and the male portion is arranged on the housing.

Alternatively to or in combination with the snap button, the coupling may comprise a magnet for connecting the patch and the housing to each other. The use of a magnet for attaching the housing to the patch will facilitate the handling of the device, since there is no or reduced need of using a relatively large force for bringing two coupling parts to snap into each other. Particularly, if the housing is to be detached from the patch while keeping the patch attached to the chest of the user, this can be performed relatively easily if themagnetic force of the magnet is selected properly. This in turn will reduce any negative impact on the user.

According to a further embodiment of the device, the electrode is arranged at a distance from the connection point, and the patch is adjustable in different pivot positions about the connection point relative to the housing. Hereby, adjustment of the patch in different pivot positions while using the same connection point between the patch and the housing can be achieved. This in turn will simplify the design of the coupling.

The distance between the electrode and the connection point can suitably be in the range 10-200 mm, preferably 15-150 mm, and more preferably in the range 20-100 mm. The distance can be chosen such it will fit the user and the measurement to be performed.

According to a further embodiment of the device, the patch is pivotally connectable to the housing enab|ing pivoting of the patch about the connection point relative to the housing when the patch and the housing are connected to each other by the coupling. Hereby, a great freedom to place the electrode in the desired position during the placement of the device on the user can be achieved.

The patch can be pivotable about the connection point relative to the housing in a 30 degree pivoting range, suitably in a 90 degree pivoting range, preferably in a 180 degree pivoting range, and more preferably in a 360 degree pivoting range. Hereby, multiple or an infinite number of different pivot positions can be selected.

Although some kind of lock could be used for fixating the patch relative to the housing after the patch has been adjusted in the desired pivot position, when the device is to be applied to a user, and when using a plurality of said patch, and the connection points between the plurality of said patch and the housing are separated from each other such that each patch has its own connection point, the device will be self-locking when placed on the user, since there are at least two different pivot points.

Alternatively, the patch can be connectable to the housing at a fixed pivot position about the connection point relative to the housing, wherein the fixed pivot position is selectable from a set of different fixed pivot positions. ln this way a finite number of predetermined pivot positions can be provided.According to a further embodiment of the device, the electrode and the electronics of the housing are electrically connected to each other by an electrical connector, and the electrical connector comprises an electrical connector portion of the patch and an electrical connector portion of the housing, wherein said electrical connector portions are in contact with each other when the patch and the housing are attached to each other. Hereby, the electrical connection bet\Neen the electrode and the electronics can be achieved automatically by attaching the housing to the patch.

According to a further embodiment of the device, the electrical connector is arranged at the connection point, and preferably the electrical connector is integrated in the coupling. Hereby, any adjustment of the patch in different pivot positions about the connection point can be performed while maintaining the electric connection between the electrode and the electronics of the housing by means of a relatively robust and non-complicated design.

According to a further embodiment of the device, the electrode and the electrical connector portion of the patch are electrically connected to each other by a wire of the patch which wire extends in the patch from the electrical connector portion of the patch to the electrode. ln addition to be protected, such a wire embedded in the patch has advantages over a free wire with respect to signal quality. A free wire, cable or similar, which extends freely outside the patch and the housing from a contact point of the electronics, to the electrode, is associated with more disturbances and often poor signal quality.

Further advantages and advantageous features of the invention are disclosed in the following description and in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples. ln the drawings: Fig. 1 shows a user wearing an ECG device according to the invention,Fig. 2A is a front view of the ECG device with a housing and patches, Fig. 2B is a rear view of the ECG device in Fig. 2A, Fig. 3A is a front view of the ECG device where the housing and the patches are attached to each other, Fig. 3B is a rear view of the ECG device in Fig. 3A, Fig. 4 is a cut view along A-A in Fig. 3B, and Fig. 5 is a rear view of a variant of the ECG device.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS Fig. 1 is a front view showing a person 1 wearing an electrocardiogram (ECG) device 2. The device 2 is attached to the chest of the user 1. The wearable ECG device 2 comprises a patch 3 attached to the skin of the user 1 and a housing 4 which is attached to and carried by the patch 3. ln the example embodiment i||ustrated in Fig. 1, the device 2 comprises a plurality of said patch 3. Each patch 3 is provided with an e|ectrode 5 measuring signals from the heart of the user 1. The e|ectrode can be for example an Ag/AgCl e|ectrode covered by a gel.

The patches 3 are suitably attached to the skin of the user by an adhesive. The housing 4 contains electronics which processes the signals received from the electrodes and produces ECG data. The electrodes 5 are electrically connected to the electronics of the housing The electrodes 5 are preferably arranged at positions of the chest of the user 1 which positions have relatively low degree of muscles and fat tissue enabling a good signal quality. At the same time, the housing 4 is suitably arranged centrally on the chest between the breast muscles for convenient and safe wearing of the device ln the example embodiment i||ustrated in Fig. 1, the device 2 comprises three patcheseach having one said e|ectrode 5 measuring signals from the heart of the user 1. lnaddition, the device 2 comprises a further patch provided with a reference electrode, such as a common mode rejection electrode.

Further, a cartesian coordinate system X, Y, Z, where all axes are orthogonal to each other, is introduced in Fig. 1 for facilitating the explanation of how the device 2 is attached to the user 1. The directions and axes used herein, i.e. the X-axis, Y-axis and the Z-axis, are arranged relative to the user such that the Z-axis is a vertical axis in parallel with the longitudinal extension direction of the user (when standing up), the X-axis is a horizontal axis in parallel with the lateral extension of the user (from one shoulder to the other), and the Y-axis is a horizontal axis in parallel with the extent in depth of the user (chest to back). Thus, ”upper” and ”lower” refer to the Z-direction, ”left” and ”right” to the X- direction, and ”behind” and ”in front of” refer to the Y-direction.

For example, a first measuring electrode 5c of a first patch 3c is arranged centrally on the sternum of the user 1, preferably at a low position close to the lower end of sternum, a second measuring electrode 5b of a second patch 3b is arranged in an upper position (above the first measuring electrode) on the left side of sternum in the interspace between the fourth rib and the fifth rib of the user, and a third measuring electrode 5a of a third patch 3a is arranged in an upper position (above the first measuring electrode) on the right side of sternum in the interspace between the fourth rib and the fifth rib of the user. Of course, many other electrode patterns are also possible. For example, the first measuring electrode can be arranged centrally on the sternum of the user, the second measuring electrode can be arranged in an upper position (above the first measuring electrode) on the left side of sternum in the interspace between the second rib and the third rib of the user, and the third measuring electrode can be arranged in an upper position (above the first measuring electrode) on the right side of sternum in the interspace between the second rib and the third rib of the user.

Further, the reference electrode 5d of a fourth patch 3d is arranged centrally on the sternum at a position between the lower first measuring electrode 5c and the upper second and third measuring electrodes 5b, 5a. Since the patches 3 with the electrodes 5 are arranged behind the housing 4, the centrally arranged reference electrode 5d is covered by the housing 4 in Fig.Figs. 2A and 2B show a front view and a rear view, respectively, of the ECG device 2 where the patches 3 and the housing 4 are not attached to each other. The housing 4 has a front side 6 facing away from the user 1 and a rear side 7 facing towards the user 1 when the device 2 is attached to the chest of the user 1. Correspondingly, each patch 3 has a front side 8 facing away from the user 1 and a rear side 9 facing towards the user 1 when the patch 3 is attached to the user. A surface 10 of the rear side 9 of the patch 3 is attached to the skin of the user 1. The entire surface 10 of the rear side, except for the surface portion overlapping with the electrode position, can be provided with an adhesive.

The housing 4 suitably has a main extension in a plane intended to be arranged substantially in parallel with the chest of the user when the device 2 is worn by the user 1. ln the example embodiment i||ustrated in Fig. 2A and 2B, the rear side 7 of the housing 4 is flat and has a surface defining the plane. (The XZ-plane is in parallel with the chest in Fig. 1.) The width and height of the housing extend in parallel to this plane. The thickness of the housing 4 extends in a direction perpendicular to the plane. (The Y-direction is perpendicular to the XZ-plane in Fig. 1.) The housing 4 is suitably relatively flat and thin with a substantial smaller thickness than width and height. The thickness of the housingis shown in Fig.

Correspondingly, each patch 3 with its electrode 5 has a main extension substantially in parallel to the same plane as the housing 4. The width and length of the patch 3 extend in parallel to the plane. The thickness of the patch 3 extends in the direction perpendicular to the plane. The patch is suitably relatively flat and thin with a substantial smaller thickness than width and length.

Figs. 3A and 3B show a front view and a rear view, respectively, of the ECG device 2 where the patches 3 and the housing 4 are attached to each other. As indicated by arrows 11 each patch 3 is adjustable in different positions relative to the housing 4. The patches 3 can be adjustable in different positions relative to the housing 4 by movement of the patches 3 in parallel to the main extension plane of the housing 4. ln the example embodiment i||ustrated in Figs. 3A and 3B, each patch 3 is adjustable in multiple different positions relative to the housing 4, and particularly, each patch 3 is adjustable in different pivot positions relative to the housingFunhen disconnectable to and from each other at a connection point 12 by a coupling 13. The each patch 3 and the housing 4 are mechanically connectable and coupling direction for connection of the patch 3 and the housing 4 to each other, can be perpendicular to the main extension p|ane of the housing 4 and the patch 3. (ln Fig. 1, this coupling direction is substantially in parallel with the Y-axis.) ln other words; in Figs. 2A and 2B, the housing 4 is detached from the patches 3, i.e. disconnected from each patch by the couplings 13, and in Figs. 3A and 3B, the housing 4 is attached to the patches 3, i.e. connected to each patch by the couplings The e|ectrode 5 of the patch 3 is preferably arranged at a distance 14 from the connection point 12. Such a distance 14, between the e|ectrode 5 and the connection point 12, may be in the range 10-200 mm, preferably 15-150 mm, and more preferably in the range 20- 100 mm.

The patch 3 is suitably adjustable in different pivot positions about the connection point 12 relative to the housing 4. The connection point 12 can be a pivot point for pivoting the patch 3 and the housing 4 relative to each other. A pivot axis 15 for the pivot motion suitably extends through the pivot point 12 in the coupling direction which direction can be perpendicular to the main extension p|ane of the housing 4. See also Fig. 4. (ln Fig. 1, the pivot axis 15 extends substantially in parallel with the Y-axis.) The patch 3 can be pivotally connectable to the housing 4 enab|ing pivoting of the patch 3 about the connection point 12 relative to the housing 4 when the patch 3 and the housing 4 are connected to each other by the coupling 13. ln Figs. 3A and 3B, for illustration purposes, two different pivot positions 16, 17 of the lower patch are shown, where one pivot position 17 of the pivot positions is indicated by dotted lines.

The patch 3 can be pivotable about the connection point 12 relative to the housing 4 for example in a 30 degree pivoting range, suitably in a 90 degree pivoting range, preferably in a 180 degree pivoting range, and more preferably in a 360 degree pivoting range.

Although two or more patches could have a connection point in common, in the example embodiment illustrated in Figs. 3A and 3B, the connection points 12 between the plurality of said patch 3 and the housing 4, are separated from each other such that each patchhas its own connection point for connection and disconnection to the housing 4. For each patch 3, the device 2 comprises one said coupling 13. This also means that each patch 3 has its own pivot point 12 and pivot axis 15 and each patch 3 is individually adjustable in different pivot positions, not only relative to the housing 4, but also relative to the remaining of the plurality of said patch.

Alternatively to pivotable patches, the patch can be connectable to the housing at a fixed pivot position about the connection point relative to the housing, where the fixed pivot position being selectable from a set of different fixed pivot positions. For example, the different positions 16, 17 of the lower patch illustrated in Figs. 3A and 3B, could constitute two such selectable different fixed positions. ln such a case, preferably, multiple such predetermined fixed pivot positions are provided for enabling various pivot positions of the patch.

The coupling 13 is further illustrated in Fig. 4 showing an enlarged cut view along A-A in Fig. 3B. The coupling 13 may have a first coupling member 18 arranged in the housing 4 and a second coupling member 19 arranged in the patch 3. See also Figs. 2A and 2B. The first coupling member 18 and the second coupling member 19 are engageable with each other. For example, the coupling 13 can comprise a snap button having a female portion 18 and a male portion 19, where one of the female portion and the male portion is arranged on the patch and the other of the female portion and the male portion is arranged on the housing. As illustrated in Fig. 4, the female portion 18 is arranged in the housing 4 and the male portion 19 is arranged in the patch 3, for instance.

Alternatively, or in combination with such coupling members 18, 19, the coupling 13 may comprise a magnet 20 for connecting the patch 3 and the housing 4 to each other. For example, the housing 4 may comprise a permanent magnet 20, optionally arranged in the first coupling member 18, and the patch 3 has a portion of a ferromagnetic material, optionally arranged in the second coupling member Each electrode 5 and the electronics 21 of the housing 4 are electrically connected to each other by an electrical connector 22 comprising an electrical connector portion 23 of the patch 3 and an electrical connector portion 24 of the housing 4. The electrical connector 22 is configured such that the electrical connector portions 23, 24 are in contact with each other when the patch 3 and the housing 4 are attached to each other by means of the coupling 13. The electrical connector 22 is suitably arranged at the connection point12, and preferably integrated in the coupling 13 as shown in Fig. 4. Further, the electrode 5 and the electrical connector portion 23 of the patch 3 are suitably electrically connected to each other by a wire 25 of the patch 3, which wire 25 extends in the patch 3 from the electrical connector portion 23 of the patch to the electrode 5. An electric connection for transferring the signals measured by the electrode 5 to the electronics 21 of the housingis thereby established when the housing 4 is attached to the patch As illustrated in Fig 4, the housing 4 is hollow for accommodating the electronics 21 inside the housing. The electronics may comprise a processing unit for achieving electrical communication with the electrodes and producing ECG data based on the received signals from the electrodes, and memories for storing such ECG data. The electronics suitably comprises amplifiers, A/D converters, etc., for processing the signals received from the electrodes. ln addition, batteries, modulators, filters and other standard electronic components can be used.

Fig. 5 shows a variant of the ECG device 2 provided with three patches 3 each having a measuring electrode 5. The specific features for this example embodiment is described hereinbelow. As it regards all other features, reference is made to the description hereinabove.

The rear side 7 of the housing 4 facing towards the user 1, when the device is attached to the chest of the user, is shown.

Each patch 3 is moveably attached to the housing 4 for rectilinear movement of the patch 3 relative to the housing 4 for adjustment of different positions of the patch 3 relative to the housing 4. The housing 4 may be provided with a slot 26 along which the connection point 12 between the housing 4 and the patch 3 can be moved in the longitudinal direction 27 of the slot 26. Further, the device suitably comprises a lock for locking the patch 3 in the desired position relative to the slot 26 and the housing ln the example embodiment illustrated in Fig. 5, the electrical connector which connects the electrode and the electronics of the housing electrically to each other, may comprise for example a connector rail arranged in the housing along the slot allowing electrical contact for any position of the patch.lt is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person Will recognize that many changes and modifications may be made within the scope of the appended claims.

Claims

CLAIMS A wearable electrocardiogram device (2) comprising a patch (3) to be attached to the chest of a user (1) and a housing (4) which is attached to and carried by the patch when the device is in operation, the patch (3) being provided with an electrode (5) measuring signals from a heart, the housing (4) containing electronics (21) which processes such signals received from the electrode (5) and produces electrocardiogram data, the patch (3) and the housing (4) being mechanically connectable and disconnectable to and from each other at a connection point (12) by a coupling (13), the patch (3) being adjustable in different pivot positions relative to the housing (4), the patch (3) being moveably attached to the housing (4) by a slot (26) along which the connection point (12) between the housing (4) and the patch (3) can be moved for rectilinear movement of the patch relative to the housing for adjustment of different positions of the patch relative to the housing. A device according to claim 1, characterized in that the electrode (5) is arranged at a distance (14) from the connection point (12), and the patch (3) is adjustable in different pivot positions about the connection point (12) relative to the housing (4). A device according to claim 2, characterized in that the distance (14) between the electrode (5) and the connection point (12) is in the range 10- 200 mm, preferably 15-150 mm, and more preferably in the range 20-mm. A device according to claim 2 or 3, characterized in that the patch (3) is pivotally connectable to the housing (4) enabling pivoting of the patch about the connection point (12) relative to the housing when the patch and the housing are connected to each other by the coupling (13). A device according to claim 4, characterized in that the patch (3) is pivotable about the connection point (12) relative to the housing (4) in a 30 degree pivoting range, suitably in a 90 degree pivoting range, preferably in a180 degree pivoting range, and more preferably in a 360 degree pivoting range. A device according to claim 1, characterized in that the patch (3) is connectable to the housing (4) at a fixed pivot position about the connection point (12) relative to the housing, the fixed pivot position being selectable from a set of different fixed pivot positions (16, 17). A device according to any of claims 1-6, characterized in that the coupling (13) comprises a snap button having a female portion (18) and a male portion (19), one of the female portion and the male portion being arranged on the patch (3) and the other of the female portion and the male portion being arranged on the housing (4). A device according to any of claims 1-7, characterized in that the coupling comprises a magnet (20) for connecting the patch (3) and the housing (4) to each other. A device according to any preceding claim, characterized in that the electrode (5) and the electronics (21) of the housing (4) are electrically connected to each other by an electrical connector (22), the electrical connector comprising an electrical connector portion (23) of the patch (3) and an electrical connector portion (24) of the housing (4), said electrical connector portions (23, 24) being in contact with each other when the patch (3) and the housing (4) are attached to each other. A device according to claim 9, characterized in that the electrical connector (22) is arranged at the connection point (12). A device according to claim 10, characterized in that the electrical connector (22) is integrated in the coupling (13). A device according to any of claims 9-11, characterized in that the electrode (5) and the electrical connector portion (23) of the patch are electrically connected to each other by a wire (25) of the patch (5) which wire extends inthe patch from the electrical connector portion (23) of the patch to the electrode (5). A device according to any preceding claim, characterized in that the device (2) comprises a plurality of said patch (3), each patch being provided with one said electrode (5). A device according to claim 13, characterized in that the connection points (12) between the plurality of said patch (3) and the housing (4) are separated from each other such that each patch (3) has its own connection point. A device according to claim 13 or 14, characterized in that at least one patch (3) is individually adjustable in different positions relative to the housing (4) and relative to the remaining of the plurality of said patch (3). A device according to any preceding claim, characterized in that the device (2) comprises three said patches (3a, 3b, 3c) each having one said electrode (5a, 5b, 5c) measuring signals from the heart, and a further electrode (5d) being a reference electrode.