ECG ELECTRODE PATCH DEVICE AND METHOD FOR
ELECTROCARDIOGRAPHY
Technical field
[0001 ] The present description relates generally to electrocardiography (ECG) and in particular to novel methods for performing ECG measurements in the sagittal plane, in particular ambulatory ECG, and to devices and electrodes for use in said method.
Background
[0002] ECG is an established technology for recording the electric activity of the myocardium and detecting the transmission of the cardiac impulse through the conductive tissues of the muscle. ECG allows the observation of the function of the heart, and makes it possible to diagnose specific cardiac abnormalities. Electrodes are affixed to specific anatomic points on the patient's body, normally on the chest (precordium) and on the extremities.
[0003] ECG is generally performed with the use of three or four peripheral electrodes placed on the limbs, and six electrodes placed on the precordium, i.e. the patient's chest. The peripheral electrodes are designated I to III and the precordial electrodes are designated V1 , V2, V3, V4, V5, and V6 to indicate the positions on the precordium on which the electrodes are placed.
[0004] The peripheral electrodes are used to determine the electrical axis, which is usually measured only in the coronal plane, while the precordial eletrodes are used to record the ECG in the transverse or horizontal plane. The electric activity is recorded and traditionally displayed as an electrocardiogram, exhibiting a characteristic waveform, illustrating the contractions of the heart atria and ventricles, their frequency and duration. Deviations from the normal pattern are called
arrhythmias, for example atrial fibrillation, atrial flutter, heart block, premature contraction, and sinus arrhythmias. Other examples are tachycardia, a heart rate of more than 100 beats per minute, and bradycardia, a heart rate of fewer than 60 beats per minute. [0005] When performing ECG on a resting patient, in supine position, the number of electrodes is not an issue. Normally ten electrodes are used, but it is also possible to use twelve or more. Resting ECG is performed during a limited time, and as the name discloses, requires that the patient is resting. Some arrhythmias are however occurring irregularly, or only under special circumstances, and will thus not be detected during resting ECG. It is therefore often desirable to perform continuous, ambulatory ECG recording. This could be the case for patients where heart problems are suspected, or patients recovering from an infarct. Patients investigated for receiving a pacemaker are another group where continuous, ambulatory ECG recording is desired. Yet another group of patients requiring an improved, yet more simple and easily performed ECG are patients in transit, e.g. in emergencies, during ambulance transport to a hospital, or during transfer within or between hospitals. Further, there is a growing interest for home monitoring of various health parameters, such as ECG.
[0006] Continuous, ambulatory ECG recording is performed today mainly by using the non-invasive Holter-method, connected to traditional ECG electrodes, or invasive methods, where a heart monitor is inserted sub-cutaneously. In the Holter- method, a portable recorder is carried by the patient, while the patient conducts normal daily activities. In the Holter-method, it is of course desirable to minimize the number of electrodes. Consequently, there exist instructions for the use of 2, 3, 5 or 7 electrodes. In the case of two electrodes, these are placed diagonally across the chest, one on the fifth rib, along the left anterior, axillar line, and the other on the right clavicula (collar bone). Using three electrodes, these are placed on the right and left collar bones, and on the fifth rib, along the left anterior, axillar line. Also with these positions, there will be multiple attachment points, and cables crisscrossing the chest of the patient. The method is also prone to disturbances, and the result is dependent on the exact positioning of the electrodes. As a consequence, the results of Holter monitoring are often difficult to interpret.
[0007] A single patch with multiple electrodes has been disclosed in US
5,947,897 but in that document, the objective is to simplify the positioning of the electrodes. According to the method disclosed in US 5,947,897 the ECG apparatus then choses the electrode from those on the patch, which gives the best signal. [0008] US 5,184,620 and US 7,266,405 on the other hand show "multiple electrode pad assemblies" where twelve electrodes are attached to a flexible sheet, simplifying the positioning of the electrodes and minimizing the number of cables going from the patient to the ECG recording apparatus.
[0009] US 20070149887 shows schematically a portable electrocardiogram (ECG) measurement device formed of an ECG measurement patch including at least three electrodes and attached to a body of a subject to receive a pseudo ECG signal of the subject via the electrodes and an ECG measurement controller physically attached and electrically connected to the ECG measurement patch via a
predetermined connector, receiving and converting the pseudo ECG signal into a digital signal, and transmitting the digital signal to a predetermined memory or a pseudo ECG signal analysis apparatus connected via a wired/wireless network.
[0010] WO 2008/137162 concerns electrocardiography and electrode
arrangements used in electrocardiographic monitoring devices, and is more particularly related to a pad or patch containing said electrodes which may be used to passively and non-invasively monitor electrical activity generated by a patient s heart from the surface of that patient's chest, and to a connector which allows for fast and simple connection between the pad containing said electrodes and the devices and equipment typically used to monitor and view electrocardiographic information.
[001 1 ] WO 2013/175457 discloses a cable for use in biopotential
measurements in a magnetic resonance (MR) environment comprising a flexible plastic or polymer sheet extending as a single unitary structure from a first end to an opposite second end, and an electrically conductive trace disposed on the flexible plastic or polymer sheet and running from the first end to the opposite second end. The electrically conductive trace has sheet resistance of one ohm/square or higher, and may have a hatching or checkerboard pattern. The cable may further include an electrically insulating protective layer disposed on the substrate and covering the electrically conductive trace, an electrode disposed on the electrically conductive trace at the second end, an edge connector at the first end, or various combinations of such features. [0012] Patches comprising multiple electrodes, intended to be attached to the skin of a patient have also been disclosed in a different context, namely for transcutaneous electric nerve stimulation (TENS) and transdermal drug delivery.
Summary
[0013] In the light of the state of the art, it remains to simplify the performance of electrocardiography (ECG), to simplify the placement of the electrodes, to minimize the number of electrodes used, and in particular to make possible ambulatory ECG without compromising the accuracy and reliability of the measurements.
[0014] A first aspect is thus an electrocardiography electrode device adapted for attaching to the skin of a patient, wherein said device is adapted for positioning in the axilla of said patient, said device comprising an adhesive patch and electrodes positioned on said adhesive patch, and an interface for transmitting
electrocardiography signals from said electrodes to a device for storing and/or recording an electrocardiogram.
[0015] According to an embodiment of said first aspect, said interface
comprises a connection for detachably connecting a communication device.
Preferably said communication device comprises a programmable circuit board including a wireless communication device, adapter or interface, for example a narrowband communication adapter, for example but not limited to a Bluetooth adapter or a Wi-Fi adapter.
[0016] According to an embodiment, freely combinable with any of the above embodiments, said communication device further comprises an accelerometer and a temperature sensor. Preferably said communication device further comprises a gyro.
[0017] According to another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a GPS module.
[0018] According to another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a subscriber identity module (SIM) and a circuit for mobile communication.
[0019] According to a preferred embodiment of said first aspect, freely combinable with any of the above embodiments, the connection for detachably connecting a communication device is located within a pocket for receiving said communication device.
[0020] According to another embodiment, freely combinable with any of the above embodiments, the electrode device comprises between 4 and 8 electrodes.
[0021 ] According to another embodiment, freely combinable with any of the above embodiments, said electrode device or patch comprises an elongated part or flap for attaching one electrode to the anterior part of the chest.
[0022] According to yet another embodiment, freely combinable with any of the above embodiments, said electrode device comprises an elongation or flap for attaching one electrode to the anterior part of the ribcage and another elongation or flap for attaching another electrode to the posterior part of the ribcage.
[0023] A second aspect is thus method for performing electrocardiography on a patient, comprising the following steps
- providing an adhesive patch having electrodes positioned on said patch and an interface for transmitting electrocardiography signals from said electrodes to a device for storing and/or recording an electrocardiogram;
- attaching said patch to the skin of said patient in the axilla of said patient; and
- transmitting electrocardiography signals from said electrodes to a device for storing and/or recording an electrocardiogram.
[0024] According to an embodiment of said second aspect, said interface comprises a connection for detachably connecting a communication device, preferably a device for wireless communication.
[0025] According to an embodiment thereof, said communication device comprises a programmable circuit board including a wireless communication device, interface or adapter, preferably a narrowband communication adapter, for example a device, interface or adapter chosen from a Bluetooth adapter and a Wi-Fi adapter, and the device is capable of sending and receiving wireless signals.
[0026] According to yet another embodiment of the method, freely combinable with any of the above embodiments said communication device further comprises an accelerometer and a temperature sensor and motion and temperature is recorded. [0027] According to yet another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a gyro, and the orientation of the device is recorded.
[0028] According to yet another embodiment of the method, freely combinable with any of the above embodiments said communication device further comprises a GPS module, and the location of the device is recorded.
[0029] According to yet another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a subscriber identity module (SIM), a circuit for mobile communication, and the device is capable of sending and receiving signals over the cellular network.
[0030] According to a preferred embodiment of said second aspect, freely combinable with any of the above embodiments, the connection for detachably connecting a communication device is located within a pocket for receiving said communication device, the communication device is inserted in said pocket and detachably connected when the electrocardiography recording is commenced, and removed and disconnected with the recording is stopped.
[0031 ] According to yet another embodiment of the method, freely combinable with any of the above embodiments, the communication device is removed and the adhesive electrode device is discarded after use. Preferably the communication device is refurbished.
[0032] According to a preferred embodiment of said second aspect, freely combinable with any of the above embodiments, said electrode device is placed in the axilla, and an elongation or flap with one electrode is attached to the anterior part of the chest.
[0033] Preferably said electrode device is placed in the axilla, and a flap with one electrode is attached the anterior part of the chest and another flap with another electrode is attached to the posterior part of the ribcage.
[0034] Another aspect is a system for ambulatory electrocardiography comprising an adhesive electrode device for attaching in the axilla of a patient, a communication device detachably connected to said electrode device, and a device for storing and/or recording an electrocardiograph. [0035] According to an embodiment of said third aspect, said communication device and said device for storing and/or recording an electrocardiogram are in wireless contact with each other.
[0036] According to another embodiment, said device for storing and/or recording an electrocardiogram optionally also comprises a display for displaying an electrocardiogram and/or for displaying alerts, error messages, status indicators etc. Preferably said device for storing and/or recording an electrocardiogram comprises a device for linking the electrocardiogram to other features recorded by the device, such as temperature, orientation, movement and position of the device.
[0037] Further aspects and embodiments will become apparent to a person skilled in the art upon study of the figures and the following detailed description and examples.
Brief description of the drawings
[0038] The invention and embodiments thereof will now be described, by way of example, with reference to the accompanying drawings, in which:
Figure 1 illustrates the positioning of an electrode patch in the axilla or armpit of a human subject, with a cable or cables leading to a recording device and/or transmitting device here illustrated as a device placed in the pocket of said subject.
Fig. 2 illustrates the positioning of an electrode patch in the armpit of a human subject in an embodiment wherein an electrode patch has an attached communication device, capable of communicating with an external device, such as but not limited to a smartwatch, a smartphone, a personal computer or similar device, here illustrated as a smartphone in the hand of the subject. .
Fig 3A schematically shows an embodiment of an electrode patch having four electrodes, and four wires joined as one cable exiting the patch.
Fig. 3B shows a cross-section of the patch in Fig. 3A. Fig. 4A schematically shows an embodiment of an electrode patch having a connection or port for the releasable attachment of a separate a
communication device.
Fig. 4B shows a cross-section of the patch in Fig. 4A.
Fig. 5 schematically shows an embodiment of an electrode patch having a connection or port for the releasable attachment of a cable having a number of wires corresponding to the number of electrodes of the patch.
Fig. 6A shows a perspective view of an electrode patch according to an embodiment, having four electrodes and a connection or port for the releasable attachment of a communication device or a cable, as well as a detachable release liner.
Fig. 6B shows a perspective view of the embodiment of Fig. 6A, where said release liner is partially removed and the adhesive surface of the electrode patch and one electrode is partially exposed.
Fig. 7 schematically shows an embodiment of an electrode patch having a connection or port for the releasable attachment of a separate recording device and/or transmitting device, wherein said device is insertable into a pocket formed on the electrode patch.
Fig. 8 shows a cross-section of the patch in Fig. 7.
Fig. 9 is perspective view of the patch in Fig. 7 with the recording device and/or transmitting device inserted.
Fig. 10A and 10B schematically show embodiments of an electrode patch having 6 electrodes, wherein the patch has an inverted T-shape, with a cable (A) or with a connection (B) respectively.
Fig. 1 1 A and 1 1 B schematically show embodiments of an electrode patch having 6 electrodes, wherein the patch is T-shaped, with two elongations or flaps, and with a cable (A) or with a connection (B) respectively.
Fig. 12A and 12B schematically show embodiments of an electrode patch having 6 electrodes, wherein the patch is substantially Y-shaped, with two elongations or flaps, and with a cable (A) or with a connection (B) respectively. Fig. 13A and 13B schematically show embodiments of an electrode patch having 6 electrodes, wherein the patch is substantially pear-shaped, with a cable (A) or with a connection (B) respectively.
Fig. 14A and 14B schematically show embodiments of an electrode patch having 6 electrodes, wherein the patch has the shape of an inverted pear, with a cable (A) or with a connection (B) respectively.
Fig. 15A and 15B schematically show embodiments of an electrode patch having 6 electrodes, wherein the patch has an oblong, e.g. an ellipsoid shape, with a cable (A) or with a connection (B) respectively.
Fig. 16 illustrates the different components of a patch and a separate recording device and/or transmitting device according to an embodiment.
Fig. 17 illustrates the positioning of an electrode patch in the armpit of a human subject in an embodiment wherein an electrode patch has elongations or flaps reaching a distance onto the anterior and posterior part of the ribcage of the subject, wherein the patch has an attached separate communication device, e.g. a recording and/or transmitting device.
Fig. 18 shows a perspective view of a substantially Y-shaped electrode patch having 6 electrodes and elongations or flaps adapted for reaching to anterior and posterior positions on a subject, and having attached a separate communication device, e.g. a recording and/or transmitting device.
Fig. 19 schematically shows a transversal view of the torso and upper arms, illustrating the positioning of the electrode device and anterior and posterior flaps.
Description of embodiments
[0039] Before the present invention is described, it is to be understood that the terminology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims and equivalents thereof. [0040] It must be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.
[0041 ] The term "electrocardiography" is used in its broadest sense, including all methods for recording the electric activity of the myocardium and detecting the transmission of the cardiac impulse through the conductive tissues of the muscle, regardless if this is performed in a clinical setting, to detect a malfunctioning of the heart, or in a sports or private setting, monitoring the normal functioning of the heart.
[0042] The term "patient" primarily indicates both human patients and healthy humans, but also other mammals can be investigated using the disclosed method and electrode, provided that one considers the anatomy of the mammal in question, and provided that certain adaptations are made.
[0043] The term "ambulatory" is used to distinguish from measurements performed on a resting patient, and thus encompass situations where the patient can move around, either in a hospital setting, e.g. recovering from an infarct, or outside the hospital, either during convalescence or conducting a normal life. Another contemplated area of use is the monitoring of athletes.
[0044] A first aspect is thus an electrocardiography electrode device adapted for attaching to the skin of a patient, wherein said device is adapted for positioning in the axilla of said patient, said device comprising an adhesive patch and electrodes positioned on said adhesive patch, and an interface for transmitting
electrocardiography signals from said electrodes to a device for storing and/or recording an electrocardiograph.
[0045] The device is preferably adapted for placement in the left axilla of the patient, as illustrated in Fig. 1 , 2 and 17. It is preferably placed in or around the anterior axilla fold, or higher. The exact placement of the patch is adjustable depending on the anatomy of the patient, accumulation of muscles or subcutaneous fat etc. A skilled person will be able to determine the optimal position of the patch in or around the axilla. It is also contemplated that the patch is placed not in the left, but in the right axilla, the exact positioning again being determined by the skilled person attaching the patch to the patient. [0046] Figure 1 shows how an electrocardiography electrode device (1 ) is placed in the left axilla of a human subject, and where the device has an interface, here shown as a cable (2) connected to a device (3) for storing and/or recording an electrocardiograph.
[0047] Figure 2 shows a preferred embodiment where an electrocardiography electrode device (1 ) is placed in the left axilla of a human subject. The interface for transmitting electrocardiography signals from said electrodes to a device for storing and/or recording an electrocardiogram is here shown as a communication device (4) and the device for storing and/or recording an electrocardiogram is here exemplified as a smartphone (5). A smartphone, smartwatch or table computer, or a personal computer for that matter, can preferably have suitable software stored thereon, giving the possibility not only to record and display the electrocardiograph, but also to analyze the same. These devices are also preferably adapted for use with systems and software for electronical medical records (EMR).
[0048] Instead of an external device carried on the person, such as for example a smartwatch or smartphone, the external device can be more distant, such as a central computer accessed wirelessly. Alternatively, the device is preferably adapted for communicating with the so called cloud, engaging in cloud computing using a network of remote servers hosted on the Internet to store, manage, and process data.
[0049] In an embodiment as the one schematically illustrated in Fig. 1 , the electrode device can be as shown in Fig. 3A and 3B, where four electrodes (10, 1 1 , 12, 13) are show attached to a flexible backing (30), which can be any suitable flexible material such as textile, plastic foil, non-woven, as conventionally used for adhesive tape, adhesive dressings and bandages. Preferably said backing is impervious to water but still breathable, for example made of a breathable but waterproof fabric membrane, such as but not limited to Gore-Tex® (W.L. Gore & Associates), SympaTex® (Sympatex Technologies), Neo Shell® (Polartec), eVent® (GE Energy), or similar breathable waterproof membranes.
[0050] The function of the backing (30) is to maintain the position of the electrodes and to provide mechanical stability to the device. The backing also serves to stabilize the cables connecting the electrodes with the cable (50) from moving. The side (20) facing the skin of the patient is made of or coated with an adhesive. The electrode surfaces are either bare, or coated with an electrically conductive adhesive or gel. It is important to choose the adhesive material so, that electric connection between the electrodes is prevented. The adhesive surface is preferably covered with a release liner (not shown) protecting the adhesive surface during storage.
[0051 ] Fig. 3A shows how the electrodes (10, 1 1 , 12, and 13) can be positioned, and how each electrode has its own wire, here illustrated by the wire (40) connecting one of the electrodes (13). All wires are preferably collected in one cable (50). The cross-section shown in Fig. 3B shows the backing (30), electrodes (10, 1 1 ,12, 13) and one wire (40) as well as the cable (50).
[0052] According to an embodiment of this aspect, the number of electrodes is 4 - 8, preferably 4 or 6. It is contemplated that the number of electrodes included in the patch is 4, 6 or 8. Preferably the number of electrodes is four, but a higher number of electrodes will allow for improved resolution.
[0053] According to an embodiment of said first aspect, said interface
comprises a connection for detachably connecting a communication device.
Preferably said communication device comprises a programmable circuit board including a wireless communication adapter chosen from a Bluetooth adapter and a Wi-Fi adapter.
[0054] This is illustrated in Fig. 4A and 4B, where a backing (30) and electrodes (e.g. 10) are shown, as well as one wire (40). The interface is however here provided as a connection (60) which can be any standardized connection or port such as an USB, micro-USB, SD, or micro-SD, but not limited thereto. Attachable thereto is a communication device (100) having the matching connection (1 10). In a device as illustrated in Fig. 4A, possible artefacts arising from the unsettling of the cables (e.g. 40) connecting the electrodes with the communication device (100) are entirely avoided, as the short cables are firmly held between the backing (30) and the adhesive surface, and prevented from moving.
[0055] Fig. 4B shows a cross-section, where positions (10), (20), (30) and (40) represent the electrode(s), adhesive surface, backing and wire(s) and the port or connection is shown as position (60). [0056] Fig. 5 illustrates an embodiment of an electrode device with a backing (30) and electrode(s) (10) having a connection or port (60) for the releasable attachment of a cable (80) having a number of connecting surfaces (70)
corresponding to the number of wires (40) and electrodes (10) of the patch.
[0057] Fig. 6A shows a perspective view of an electrode device or patch according to an embodiment, where the backing (30) covers and supports the electrodes (e.g. the electrode shown as 10) and a connection or port (60). A release liner (35) is shown. Fig. 6B shows the release liner (35) partially removed, exposing the adhesive surface (20) and the surface of one electrode (10). The exact shape and size of the electrode device or patch, as well as the placement of the electrodes can vary. The placement of the electrodes is discussed in closer detail in relation to Fig. 17.
[0058] According to a preferred embodiment of said first aspect, freely combinable with any of the above embodiments, the connection for detachably connecting a communication device is located within a pocket for receiving said communication device. This is illustrated in Fig. 7, where the connection (60) is covered by an additional layer forming a pocket (65) capable of holding the communication device (100) in a snug fit. Fig. 8 shows a cross-section and Fig. 9 shows a perspective view of the same embodiment.
[0059] An advantage of this embodiment is that the communication device is protected, and in particular the connection (60) and the matching connection (1 10) making the entire arrangement substantially waterproof. This also makes the device less conspicuous to wear. Using a skin colored backing, the device can be worn also without clothes, for example during exercise. The protective pocket would also allow the patient to wash up, perhaps even to take a shower.
[0060] Preferably the size of the adhesive patch comprising said electrodes is less than about 10 x 10 cm, preferably less than 8 x 8 cm, most preferably less than 6 x 6 cm. According to an embodiment, the shape of the patch is preferably rectangular or elliptic, or any other shape having a length and a width, wherein the length is discernably longer than the width, a feature which aids in the correct positioning of the patch. [0061 ] Preferably the electrode device and the adhesive patch is designed in a shape aiding in correct placement of the same, e.g. rectangular, T-shaped including shaped as an inverted T, pear-shaped including shaped as an inverted pear, heart- shaped or substantially heart-shaped, elongated, oval, or elliptical. The patch may also carry printed instructions in the form of pictures, e.g. a schematic instruction showing where the patch should be placed, an arrow, a pictogram or text, e.g. a short text explaining how the patch should be placed.
[0062] Different shapes are illustrated in Fig. 10A and 10B, where the device has the shape of an inverted T, aiding in positioning the device. Fig. 10A shows an embodiment where the interface is a cable (50) and Fig. 10B shows an embodiment where the interface comprises a connection or port (60). In both embodiments, the interface is on the side of lower side of the device, also in order to further aid in the correct positioning of the device.
[0063] According to another embodiment, freely combinable with any of the above embodiments, the electrode device comprises between 4 and 8 electrodes.
[0064] According to yet another embodiment, freely combinable with any of the above embodiments, said electrode device comprises an elongation or flap for attaching one electrode to the anterior part of the chest.
[0065] According to yet another embodiment, freely combinable with any of the above embodiments, said electrode device comprises an elongation or flap for attaching one electrode to the anterior part of the ribcage and another flap for attaching another electrode to the posterior part of the ribcage. The use of these flaps allows a greatly improved resolution and makes it possible to record a 3- dimensional ECG.
[0066] Fig. 1 1 A and 1 1 B schematically show embodiments where the backing (30) comprises such extended flaps (31 , 32) allowing the placement of one electrode on the anterior side of the ribcage and one on the posterior side of the ribcage of a patient. This is also illustrated in Fig. 17 and Fig. 18, showing an embodiment of the device (200) having flaps or arms (201 , 202) making it possible to position electrodes (210, 220) securely on the anterior and posterior side of the ribcage. It is conceived that the anterior electrode is placed on the upper part of the pectoralis major, under the clavicle and the posterior electrode placed on the upper half of the trapezius. This is indicated in Fig. 17 and Fig. 19.
[0067] Fig. 12A and 12B show embodiments where the device is substantially Y-shaped with extended flaps (31 , 32). It is important to note that the cables (41 , 42) are contained between the backing (30) and the adhesive surface, and thus effectively prevented from moving and causing interfering signals.
[0068] Fig. 13A and 13B show embodiments where the device is substantially pear-shaped, and in Fig. 14A and 14B, the device has an inverted pear-shape. The configuration of the electrodes shown here is an example currently preferred, where four electrodes form a square or rectangle, and two electrodes are placed more distant, outside the perimeter of said square or rectangle. This configuration is applicable to different embodiments, and freely combinable with all embodiments disclosed herein.
[0069] Fig. 15A and 15B illustrate embodiments where the device has an oblong, ellipsoid shape. In all embodiments, the interface, a cable (50) or a
connection or port (60) is shown as placed in the lower part of the device, intended to aid in the correct positioning of the device.
[0070] It is to be understood that the flaps shown in Fig. 10A, 10B, 1 1 A, 1 1 B, 12A, 12B, 17, 18 and 19 can be of different length. It is preferred that the device and patch is supplied in different sizes, and with flaps of different lengths in order to accommodate patients of different stature.
[0071 ] As explained in relation to the method, and equally applicable to the device, it is contemplated that the patch is placed in or around the anterior axilla fold, or higher. Preferably the patch is attached right under the hairline in the axilla fold. In the case that the subject is very hairy, it may be necessary to shave the armpit to make sure that good attachment of the patch is achieved, and that the electrodes are in proper connection with the skin of the patient. One advantage with the device and method is however that in most subjects, even in subjects with a hairy chest, this part of the torso is usually less hairy, and the electrode patch can be attached without prior shaving.
[0072] The exact placement of the patch is adjustable depending on the anatomy of the patient, accumulation of muscles or subcutaneous fat etc. A skilled person will be able to determine the optimal position of the patch in or around the axilla. It is also contemplated that the patch is placed not in the left, but in the right axilla, the exact positioning again being determined by the skilled person attaching the patch to the patient.
[0073] As shown in Fig. 1 , the electrocardiography electrode device (1 ) is adapted for placement in the axilla or armpit of a subject, here shown as placed in the left armpit which also is the preferred placement. It is however possible to place the electrocardiography electrode device also in the right armpit, or in other positions on the torso, although the left armpit is the preferred position due to the proximity to the heart.
[0074] According to an embodiment, freely combinable with any of the above embodiments, said communication device further comprises an accelerometer and a temperature sensor. Preferably said communication device further comprises a gyro.
[0075] According to another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a GPS module.
[0076] According to another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a subscriber identity module (SIM) and a circuit for mobile communication.
[0077] The above is illustrated in Fig. 16, schematically showing the device (1 ) comprising at least one electrode (10) with one wire (40) connecting to an interface, here shown as a connection or port (60). Detachably attached to said port (60) using a matching connector (1 10) is a communication device (100). This comprises a programmable circuit board having input/output capability as well as suitable sensors, for example a temperature sensor (140), a gyroscope or accelerometer (150) and a transmitter and/or receiver (130). The device (100) preferably contains a processor (120) and a memory (160).
[0078] The use of a programmable circuit board and the above components make it possible to incorporate various functions into the communication device. A temperature sensor makes it possible to ascertain that the device is actually attached to a human being, in addition to recording body temperature, which notably is an important health-parameter. If the temperature measured by the device remains in a certain interval, for example 37 °C ± 1 °C, this is interpreted as a sign that the device is properly attached and the patient is healthy. If the measured temperature drops to room temperature, this is taken as an indication that the device is no longer properly attached. If the temperature on the other hand e.g. remains above 37.5 °C for more than a certain time, or raises above e.g. 38 °C, this is taken as an indication that the patient is ill, and an alarm message can be transmitted by the device.
[0079] Similarly, an accelerometer or a gyroscope can be used to monitor the movement and orientation of the device. Information obtained from an accelerometer or a gyroscope can be used to valuate the physical activity of the patient, and different events detected on the electrocardiogram can be linked to the activity of the patient, allowing for a more accurate diagnosis.
[0080] A GPS module can be used to monitor the location of the patient, either actively, or passively, transmitting information about the location of the patient only when serious cardiac events are detected on the electrocardiogram. Finally, a SIM and a circuit for mobile communication can be used for transmitting information about the activity, location, and health of the patient, and for example alert a physician if abnormalities are detected.
[0081 ] A second aspect of the present disclosure is a method for performing electrocardiography on a patient, comprising the following steps
- providing an adhesive patch having electrodes positioned on said patch and an interface for transmitting electrocardiography signals from said electrodes to a device for storing and/or recording an electrocardiograph;
- attaching said patch to the skin of said patient in the axilla of said patient; and
- transmitting electrocardiography signals from said electrodes to a device for storing and/or recording an electrocardiograph.
[0082] According to an embodiment of said second aspect, said interface comprises a connection for detachably connecting a communication device, preferably a device for wireless communication.
[0083] According to an embodiment thereof, said communication device comprises a programmable circuit board including a wireless communication adapter or interface, for example a narrowband communication adapter, for example but not limited to a Bluetooth adapter or a Wi-Fi adapter, and the device is capable of sending and receiving wireless signals.
[0084] According to yet another embodiment of the method, freely combinable with any of the above embodiments said communication device further comprises an accelerometer and a temperature sensor and motion and temperature is recorded.
[0085] According to yet another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a gyroscope and/or an accelerometer, and the location, movement and orientation of the device is recorded. As disclosed in relation to the device, an accelerometer or a gyroscope can be used to monitor the movement and orientation of the device. Information obtained from an accelerometer or a gyroscope can be used to valuate the physical activity of the patient, and different events detected on the electrocardiogram can be linked to the activity of the patient, allowing for a more accurate diagnosis.
[0086] According to yet another embodiment of the method, freely combinable with any of the above embodiments said communication device further comprises a GPS module, and the location of the device is recorded. As disclosed in relation to the device, a GPS module can be used to monitor the location of the patient, either actively, or passively, transmitting information about the location of the patient only when serious cardiac events are detected on the electrocardiogram. Finally, a SIM and a circuit for mobile communication can be used for transmitting information about the activity, location, and health of the patient, and for example alert a physician if abnormalities are detected.
[0087] According to yet another embodiment, freely combinable with any of the above embodiments, said communication device further comprises a subscriber identity module (SIM), a circuit for mobile communication, and the device is capable of sending and receiving signals over the cellular network. As disclosed in relation to the device, a SIM and a circuit for mobile communication can be used for transmitting information about the activity, location, and health of the patient, and for example alert a physician if abnormalities are detected. Different numbers can be preprogrammed, making it possible to alert medical staff, neighbors or relatives, depending on the condition detected. [0088] According to a preferred embodiment of said second aspect, freely combinable with any of the above embodiments, the connection for detachably connecting a communication device is located within a pocket for receiving said communication device, the communication device is inserted in said pocket and detachably connected when the electrocardiography recording is commenced, and removed and disconnected with the recording is stopped.
[0089] According to yet another embodiment of the method, freely combinable with any of the above embodiments, the communication device is removed and the adhesive electrode device is discarded after use. Preferably the communication device is refurbished.
[0090] According to a preferred embodiment of said second aspect, freely combinable with any of the above embodiments, said electrode device is placed in the axilla, and a flap with one electrode is attached to the anterior part of the chest.
[0091 ] Preferably said electrode device is placed in the axilla, and a flap with one electrode is attached the anterior part of the chest and another flap with another electrode is attached to the posterior part of the ribcage. This is illustrated in Fig. 17 and 19..
[0092] In Fig. 18, a communication device (100) is shown as detachably connected to the lower part of the device (200), but it can also be differently positioned, for example in a protective pocket as illustrated in Fig. 7, 8 and 9.
[0093] Fig. 18 also shows how the cables connecting the electrodes are connected to the backing and thus held securely in place. The cables lading from the communication device to the proximal electrodes are short, and securely prevented from moving. The longer wires leading to the distal electrodes (210 and 220) at the ends of he flaps (201 , 202) are also covered by the backing, and will be held in place by the adhesive. This helps avoiding or minimizing artefacts arising from the movement or stirring of the cables when the patient moves.
[0094] Fig. 19 schematically shows a transversal view of the torso (300) and upper arms (301 , 302), illustrating the approximate position of the heart (303) and the positioning of the electrode device (200) and anterior and posterior flaps (201 , 202). In an embodiment where the device (200) holds four electrodes in the central part of the device, and two distal flaps, the arrangement shown in Fig. 17 and 19allows for a 3-dimensional ECG with high resolution. The electrodes in the flaps allow for four derivations from the anterior electrode and four from the posterior electrode.
Simultaneously, the four electrodes on the central part of the device allow for six derivations. In total, a device as disclosed herein gives significantly increased resolution.
[0095] Another aspect is a system for ambulatory electrocardiography comprising an adhesive electrode device for attaching in the axilla of a patient, a communication device detachably connected to said electrode device, and a device for storing and/or recording an electrocardiograph.
[0096] According to an embodiment of said third aspect, said communication device and said device for storing and/or recording an electrocardiogram are in wireless contact with each other.
[0097] According to another embodiment, said device for storing and/or recording an electrocardiogram comprises a display for displaying an
electrocardiogram and/or alerts, status information etc. Preferably said device for storing and/or recording an electrocardiogram comprises a device for linking the electrocardiogram to other features recorded by the device, such as temperature, orientation, movement and position of the device.
[0098] According to a further embodiment of this aspect, freely combinable with the above embodiments, the electrocardiography is performed on an ambulatory patient. This can be performed as so called Holter monitoring. Using current electrodes, many patients may feel uncomfortable during the prolonged monitoring, mainly because the conspicuous electrodes and cables.
[0099] Since the recording of data is preferably done using a smart
communication bridge, completely without any cable, the problem of conspicuous and bulky cables and devices are removed. The smart communication bridge can communicate with a smartphone using Bluetooth, or directly with "the cloud" using narrowband internet of things (loT) technology. The smart communication bridge is also programmable, for example, to determine locally if an abnormal heart event has occurred. [0100] The term ambulatory should here be given a broad interpretation, including patients moving freely within the hospital setting, or in their home, or even going about their daily life, including work and leisure activities.
[0101 ] According to a further embodiment, freely combinable with the above embodiments, said electrode device or adhesive patch is adapted for attaching to the skin of the patient in the axilla of said patient in a substantially upright position, where the communication device, or in case of a cable, said cable for connecting to a device for storing and/or recording the electrocardiogram, points downwards. In other words, the design of the device guides the user to position it correctly. Similarly, when the interface is a cable, this is preferably attached to the patch in such a fashion that it extends downwards when the patch is correctly positioned.
[0102] The device then communicates wirelessly with an external device, such as a smartphone, a smartwatch, a tablet computer or a personal computer. The device can also communicate with a central computer or with the cloud, for example via the Wi-Fi network of a hospital ward, a hospital, a workplace or in the home of the patient.
[0103] The novel methods and electrodes have many advantages. Not only is the exact positioning not as critical, but the shape and size of the electrode makes it easier to place it in a correct position. The position as such and the small size of the electrode also makes it more convenient and comfortable to use during ambulatory and long-term ECG measurements. Importantly, the measurements can be made in the sagittal plane, and still allow making derivations equivalent to peripheral electrodes.
[0104] The novel methods and electrodes are equally applicable for use in the wellness and fitness sector, for use in the home, during exercise, at the gym, when jogging or engaging in other sports activities. The electrode patch is easy to use also for a layman, and owing to the reduced number of electrodes, it is easy to attach to the skin and comfortable to wear, also during extended periods.
[0105] The novel methods and electrodes are also applicable to use in a physician's office or a neighborhood medical center. This would simplify measuring the ECG of patients, for example when waiting to meet the physician. Simplified and expedited ECG measurements would allow the screening of more patients, and thus make it possible to detect heart disease at an earlier stage.
[0106] The novel methods and electrodes are particularly useful for use in ambulances, as the electrode can be easily attached and does not require the removal of clothes to any larger extent. The equipment is easy to use and requires minimal space. Based on an early ECG measurement, performed in the ambulance on the way to the hospital, a preliminary diagnosis can be made and a decision on a treatment strategy can be taken already before the patient arrives at the hospital emergency ward.
[0107] At the hospital, patients can be monitored more easily, at the ward or even allowed to move freely in the hospital. At the cardio ward, the patients can be monitored more easily and with less discomfort to the patients. The advantages of the device and method are particularly pronounced in the emergency ward, where each patient is already connected to a high number of monitoring apparatuses, and a reduction of the number or electrodes and cables will simplify the handling and reduce the risk of mistakes and confusion.
[0108] A particular advantage of the inventive placement of the electrodes close to each other and in the axilla of the patient, is that disturbing artefacts can be minimized. Artefacts can for example be due to electrical interference from skeletal muscles, outside sources and poor contact. Such artefacts are extremely common, and knowledge and understanding of them is important to prevent misinterpretation of the ECG. If an artefact is mistaken for an arrhythmia, this can lead to unnecessary diagnostic and therapeutic interventions and stress to the patient. For example very unruly patients, or patients suffering from different medical conditions such as cramps, high fever, hyperventilation, tremor, seizures etc. will present a much "cleaner" ECG when the electrodes are placed according to the invention. A device including the wireless interface will further reduce the occurrence of disturbances and artefacts.
[0109] The advantages are even more pronounced in the case of ambulatory ECG. A mobile patient will actively use the skeletal muscles creating electrical noise within the body. An ordinary activity such as combing the hair or vigorously brushing ones teeth will cause a change in the ECG which could be mistaken for an arrhythmia. Other artefacts arise when the electrodes, wires and cables are jostled or dislodged, problems which are avoided or at least significantly reduced with the device and method according to embodiments presented herein.
[01 10] A particular advantage of the flaps placed on the anterior and posterior side of the ribcage, is that this greatly simplifies the positioning of electrodes allowing the recording of a 3-dimensional ECG.
[01 1 1 ] Another significant advantage of the device and method according to embodiments presented herein is that quantitatively and qualitatively better information about the left ventricle can be gained. This will improve the diagnosis of conditions such as left ventricular hypertrophy, a condition which develops slowly and stealthily but constitutes an increased risk for acute and life-threatening
cardiovascular complications, including congestive heart failure and cardiac arrhythmias.
[01 12] Other embodiments and advantages thereof will become evident to a skilled person.
Examples
[01 13] A test series of 18 electrodes were manufactured and tested in clinical conditions, using a healthy volunteer. A slightly elastic adhesive film was used as the backing material. The electrode devices or patches each contained 4 electrodes, each with a contact surface of approximately 1 sq. cm. and positioned in a
substantially rectangular configuration on an adhesive surface. The size of the electrodes was approximately 5 x 5 cm. The contact surface of the electrodes was round, but it is conceived that other shapes are equally suitable. Figures 3A and 3B show schematically the design of the test electrodes.
[01 14] The adhesive surface made it easy to position the electrodes slightly below the armpit, on the left side of the body. The electrodes were convenient to wear, also during prolonged measurements. It was found that the size of the electrode and the distance between the electrodes can be minimized, as long as an overlap and short-circuiting was avoided. [01 15] The substantially rectangular orientation of the electrodes was confirmed to function well, the ECG measurements were performed in the sagittal plane, resulting in equivalent signals for I, II, -III in the sagittal plane using only four electrodes. The results were comparable to conventional ECG recordings for the same person, however with a lower amplitude. The quality of the signal of the signal was however good, and the reduced amplitude is only a question of amplification of the signal.
[01 16] Without further elaboration, it is believed that a person skilled in the art can, using the present description, including the examples, utilize the present invention to its fullest extent. Also, although the invention has been described herein with regard to its preferred embodiments, which constitute the best mode presently known to the inventors, it should be understood that various changes and
modifications as would be obvious to one having the ordinary skill in this art may be made without departing from the scope of the invention which is set forth in the claims appended hereto.
[01 17] Thus, while various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.