WO2015083036A1

WO2015083036A1 - Self electrocardiogram acquisition device

Info

Publication number: WO2015083036A1
Application number: PCT/IB2014/066303
Authority: WO
Inventors: Luca Fanucci; Alessandro BENINI; Massimiliano DONATI; Fabrizio IACOPETTI
Original assignee: Ingeniars S.R.L.
Priority date: 2013-12-03
Filing date: 2014-11-25
Publication date: 2015-06-11
Also published as: ITPI20130096A1

Abstract

An electrocardiographic device (40) comprises a central portion (31) and two side portions (33) that have respective conductive surfaces (1,3) configured as acquisition electrodes for receiving a raw electrocardiographic signal from a patient's (99) respective hands (98); an acquisition unit (25) electrically connected to the conductive surfaces (1,3), so as to receive the raw signal and configured for filtering it within a predetermined passband to obtain a filtered signal; a digitalization unit (18) connected to the acquisition unit (25), so as to receive the filtered signal, and configured for sampling it to obtain a digital signalized; a data interface unit (22) electrically connected to the digitalization unit (18), so as to receive the digital signalized, and configured for providing it so as it can be drawn; wherein the side portions (33) have a base surface (36) that is opposite to the conductive surfaces (1,3) configured to be arranged on a plane; a height (D) between a base surface (36) and the conductive surfaces (1,3) set between 1 cm and 8 cm, the side portions having a front edge (37) to be arranged distally with respect to the patient (99) and in such a way that the distance between the front edge (37) and the conductive surfaces (1,3) is shorter than a predetermined value (L), so that the patient (99), arranging the bases (36) on the plane (28), can cause the palm (97) of his own respective hands (98) to bear on the side portions (33), maintaining the hand palm (97) in contact with the conductive surfaces (1,3) and at the same time assisting the fingers (98") of the hands (98) to possibly rest on the plane (28). This way, by causing the hand palm to bear on the raised side portions allows to discharge a large part of the weight of the arm on the conductive surfaces substantially without any muscle tension and without any movement, which would affect the contact surface during the acquisition, and substantially without any noise associated thereto, so that a filtering passband can be chosen that has a lower limit value lower than in the prior art devices, which allows preserving a large part of the information content of the electrocardiographic signal.

Description

TITLE

SELF ELECTROCARDIOGRAM ACQUISITION DEVICE

DESCRIPTION

Field of the invention

[0001] The present invention relates to a device for obtaining an electrocardiogram (ECG) of a patient. In particular, the invention relates to a device for performing a self-acquisition of the ECG recording, i.e. a device that can be used by a patient without the support of a doctor or of a technician, in order to monitor the patient remotely.

Background of the invention. Technical problems

[0002] Chronic heart diseases are very common which oblige affected patients to periodical and frequent hearth checks. One of the most common and useful clinical tests for such cases is the electrocardiographic (ECG) examination, which is also used for monitoring the cardiac activity. Even if the ECG quality and number of electrodes are less severe for such a monitoring activity than for a complete diagnosis, presently the former type of examination is carried out, in most cases, in specialized surgeries and hospital departments, causing discomfort to the patients, who are often elderly persons, with consequent long waiting lists. On the other hand, a self electrocardiogram acquisition would be very complicated, in particular, for elderly patients of for patients who are not familiar with new technologies, due to the complexity of the devices currently known, requiring a precise positioning of several electrodes on the body and an interaction with complex user interfaces. A solution for a portable device would be desirable that provides an acceptable completeness and quality of the ECG recording and enough accessibility for carrying out the ECG examination.

[0003] In the art, portable electrocardiographic devices are also known that can be used outside of health structures and that comprise such components as electrode-bearing handles or the like, which the patient has to grip or in any case hold in such a way to allow an electric contact between the patient's hands and the electrodes, generating the electrocardiographic signal. This approach causes muscle tension, and residual movements of the patient's arms and fingers, and also the gripping force can become unsteady, in particular if the patient is an elderly and/or a weakened patient, and also the contact surface between the hands and the electrodes during the acquisition may change. All this creates a noise in the electrocardiographic signal, that can be eliminated by filtering the signal within a determined passband, causing a loss of data that could be important for monitoring the patient's cardiac activity. Therefore, such devices cannot provide electrocardiographic recordings that are well suited for monitoring a patient's condition.

[0004] Portable devices exist for obtaining ECG recordings. For instance, GB2503055 describes a mat on which the hands or the feet of a patient can be put, and which can detect an electrocardiographic signal. In order to overcome the measurement errors due to the patient's movement, the mat also comprises a movement sensor, so as to detect the patient's movement and to take them into account by subtracting from the ECG signal the vibrations they may cause.

[0005] RU2463952 describes a device for obtaining an ECG recording that can be grasped with one hand and that has a surface configured for coming into contact with the other hand. This device can generate measurement errors due to the relative movement between the two hands and due to a muscle tension that necessarily arises when gripping the device.

[0006] WO201 1031062 describes a "hand cradle" device for collecting a patient's biological data through electric signals from both the hand palm and the fingers of one hand which, if used in couple, can be adapted for an ECG examination, but has the drawbacks of requiring a double device, so also a double electronic board, as well as a cable connection system, and also the drawback of an undetermined distance between the hands during the acquisition.

Summary of the invention

[0007] It is a feature of the present invention to provide an electrocardiograph that is used with efficiency and without any assistance also by a patient who is not skilled in the use of such complex biomedical devices as professional electrocardiographs.

[0008] It is a particular feature of the present invention to provide a device that allows a patient to detect and send electrocardiogram recordings and preferably also the hearth rate autonomously, without any assistance by medical or technical operators.

[0009] It is a further particular feature of the present invention to provide an ergonomic electrocardiographic device, i.e. allowing a simple and comfortable positioning and acquisition mode to obtain the signal, so that the patient is not discouraged to carry out its own electrocardiogram acquisition whenever required.

[0010] It is a further particular feature of the present invention to provide an ergonomic device that has sufficient stability when measuring the ECG, comparable with at least the electrocardiograph signal of a first lead of a professional multi-lead electrocardiograph.

[0011] It Is a further particular feature of the present invention to provide an ergonomic device that be used in a multi lead mode, for example as a 3-lead ECG or as a 6-lead ECG.

[0012] It is a further particular feature of the present invention to provide an electrocardiograph that can send a detected electrocardiogram recording as a digital signal to any compatible receiving device (gateway), through a cable or a wireless connection.

[0013] These objects are achieved by a device for carrying out an electrocardiographic examination of a patient, the device comprising:

a central portion and two right and left side portions, said side portions having respective conductive surfaces, the conductive surfaces of the side portions configured as respective acquisition electrodes for detecting a raw electrocardiographic signal through patient's hand palms;

an acquisition unit electrically connected to the conductive surfaces, in such a way to receive the raw electrocardiographic signal, the acquisition unit configured for filtering the raw electrocardiographic signal within a predetermined passband, thus obtaining a filtered electrocardiographic signal;

a digitalization unit electrically connected to the acquisition unit, in such a way to receive the filtered electrocardiographic signal, the digitalization unit configured for sampling the filtered electrocardiographic signal, thus obtaining a digitalized electrocardiographic signal;

a data interface unit electrically connected to the digitalization unit, in such a way to receive the digitalized electrocardiographic signal, the data interface unit configured for making available the digitalized electrocardiographic signal;

wherein the main feature of said electrocardiographic device is that the side portions have a base surface that is opposite to the conductive surfaces and that is configured to be arranged on a plane, and that the side portions have a distance between a base surface and the conductive surfaces set between 1 cm and 8 cm, in such a way that the patient, leaving the base surfaces on the plane, cancan cause the hand palms to be born by the right side portion and by the left side portion, maintaining the hand palms in contact with the conductive surfaces and at the same time assisting the fingers of the hands to possibly rest on the plane on which the device is arranged.

[0014] Advantageously, the side portions have a front edge arranged to be in a distal position with respect to the patient, the front edge arranged in such a way that the distance between the front edge and the conductive surfaces is shorter than a predetermined value.

[0015] The electrocardiographic device can be configured for fully automatically sending the detected electrocardiogram recording and the measured hearth rate as a digital data flow, through the data interface unit, from which the signal can be taken in order to be locally or remotely displayed.

[0016] The electrocardiograph made as described above is an ergonomic and user-friendly device that allows substantially any patient to obtain at least a single-lead electrocardiogram recording, and to measure the hearth rate, autonomously. The patient just has to turn on the electrocardiographic device and to put the hands, in particular the proximal part of the hand palm of each hand, on a respective conductive surface, i.e. a respective electrode, and to wait for a complete valid signal acquisition to be notified.

[0017] This way, by causing the hand palm to bear on the side portions at a height D from the plane, a large part of the weight of the arm and of the hand can rest on the conductive surfaces, which allows a good signal to be exchanged by the contact with the skin. The other parts of the arm can rest on the plane, which relaxes the muscles, especially at the distal parts (the hand fingers). Therefore, the patient is enabled to establish an electric contact between the hand palm of the own hand and a respective conductive surface, i.e. a respective electrode, of the ECG device, so as to minimize the muscle tension while resting on the device, and to limit also the movements, for example the movements of the fingers, which would disturb the electrocardiographic acquisition, in particular, due to an unsteady contact area during the acquisition. For this reason, there is no need of an electrolytic gel between the electrodes and the body of the patient being examined, thus overcoming the drawbacks of the prior art devices, which require that the patient grasps or in any case have a gripping contact with such members as handles equipped with electrodes, and therefore cause the muscles to be stressed and to vibrate, causing the gripping force to become unsteady, especially in the case of elderly and/or weakened people.

[0018] The substantial absence of muscle tension and of movements of the arms and of the fingers, which is allowed by the ergonomic shape of the electrocardiographic device according to the invention, makes it possible to minimize the noise and the artifacts of the acquired signal, which in the prior art devices normally obliges to set a higher filtering passband lower limit, i.e. only a few Hz. On the other hand, the filtering passband of the acquisition unit can have a passband lower limit set between 0.2 and 1 Hz, in particular set between 0.4 and 0.8 Hz, more in particular, the passband lower limit can be about 0.5 Hz. Such a particularly small lower passband limit, which is about the same value as in a professional electrocardiograph when operating in the monitoring mode, allows only a negligible signal information content to be lost during the step of filtering. For instance, the passband may have a passband upper limit set between 35 and 45 Hz, in particular the upper limit is about 40 Hz.

[0019] Therefore, the invention provides a device that can produce at least a single-lead ECG recording that has an information content comparable to what is provided by a professional device, under a same number of ECG leads, which also makes it possible to carry out the acquisition without the direct assistance of a technician or a doctor, like in a common telemedicine procedure.

[0020] Preferably, the height of the side portions is set between 2 and 4 cm, more preferably is set between 2.5 and 3.5 cm. Preferably, the distance between the front edge of the side portions and the conductive surfaces is shorter than 5 cm, preferably is shorter than 2 cm. This way, a substantially complete muscle relaxation is allowed, and any undesired patient's movements can be avoided, which increases the above-mentioned advantages.

[0021] In an exemplary embodiment, the two right and left side portions comprise a further conductive surface adjacent to the first respective conductive surface, i.e. adjacent to the above-indicated conductive surface which serves as acquisition electrodes, said further conductive surface electrically connected to the acquisition unit, wherein the further conductive surface is configured as a common mode electrode of the ECG device. This way, a common mode electrode can be easily provided, in order to improve the quality of the recording. In particular, the further conductive surface configured as a common mode electrode comprises two right and left portions, arranged on the right and left side portions of the device, respectively, whose two conductive portions are electrically interconnected.

[0022] In another exemplary embodiment, the two right and left side portions comprise a lower conductive surface electrically connected to the acquisition unit and arranged on the base surface, so that the patient, by arranging the device on both legs while sitting, can bring the hand palm into contact with the upper conductive surfaces, i.e. with the above-described electrically conductive surfaces which serve as acquisition electrodes, and can bring the lower conductive surface into contact with the skin of the legs. Even in this case, also an elderly or weakened person can take a posture which does not involve any muscular tension or body movement, which provides the above- mentioned advantages.

[0023] The lower conductive surface can comprise a surface configured as a so-called "common mode electrode" of the ECG device. In particular the surface configured as a common mode electrode is arranged on the base surface of the right portion of the device, providing a common mode electrode that, in use, is arranged in contact with the right leg, as in the current practice.

[0024] As an alternative, or in addition, the lower conductive surface comprises a surface configured as a further acquisition electrode of the ECG device, and the acquisition unit of the electrocardiographic device comprises an electrocardiographic signal inlet unit, in turn comprising a lead selector means for bringing the electrodes into electric contact with the acquisition unit, in order to sense the voltage between the electrodes according to a plurality of ECG leads. Owing to this exemplary embodiment, the device can also be used for carrying out multiple-lead ECG examinations, for example a 3-lead ECG, in particular up to a 6-lead ECG, as it is well known in the art, by using three conventional acquisition electrodes, thus obtaining a more complete ECG recording.

[0025] In an advantageous exemplary embodiment, the electrocardiographic device comprises an elongated container whose height is equal to its distance D, and a surface of this elongated container comprises the conductive surfaces, while an opposite surface of the container comprises the above- described base surface. For instance, the container has a parallelepiped shape, in particular a thin parallelepiped shape or a plate shape, whose top surface size is comprised between 25 x 4 cm and 35 x 7 cm. This assists the patient's hand palm to be correctly arranged on the device, according to an acquisition posture.

[0026] In an exemplary embodiment, the conductive surfaces comprise two right and left rectangular electrodes, whose size is set between 1x8 cm and 3x12 cm.

[0027] Advantageously, a user interface unit is provided in the electrocardiographic device, comprising at least one interface element selected from the group consisting of:

- a power key;

a power light;

a ready light;

a heart rate light;

a progress indication display for indicating the electrocardiographic data progress acquisition.

The interface system of the device, with such a structure, is user-friendly and allows to intuitively understand the operation of the device even in case of patients that have a cognitive deficit and/or that are not so familiar with electronic devices.

[0028] In an exemplary embodiment, the data interface unit comprises a wireless data forwarding unit configured for transferring the digitalized electrocardiographic signal to a local gateway. A gateway can be any device that is suitable for receiving data from the ECG sensor through a cable or wireless connection, in particular through a Bluetooth connection, and that is suitable for forwarding the data to the final target, preferably via Internet or via a dedicated data network. For example, the gateway can be a smartphone or a tablet equipped with a special application, or it can be a PC, or an expressly designed device. The electrocardiographic device can be configured by the manufacturer, or by the service provider, in order to be connected to the predefined receiving device or gateway, by the data forwarding unit. In particular, the data forwarding unit can be a Bluetooth device.

[0029] In another exemplary embodiment, the data interface unit is configured to be connected to an advanced telephone device such as a tablet or a smartphone. In this case, the advanced telephone device can be configured, by a specific application, to make a portion of its own display to work as a progress indication display, in order to indicate the electrocardiographic data progress acquisition. For instance, the electrocardiographic device can comprise a housing such as a slot for inserting the advanced telephone device therein. Preferably, the housing for inserting the advanced telephone device is made in the central portion of the ECG device.

[0030] It falls within the field of the invention also a system for carrying out an electrocardiographic examination of a patient, comprising an electrocardiographic device configured to be connected to an advanced telephone device, and an advanced telephone device.

[0031] According to another aspect of the invention, a device is provided for carrying out an electrocardiographic examination of a patient, the device comprising:

a central portion and two right and left side portions, said side portions having respective conductive surfaces, the conductive surfaces of the side portions configured as respective acquisition electrodes for receiving a raw electrocardiographic signal through the hand palm;

a digitalization unit electrically connected to the acquisition unit in such a way to receive the filtered electrocardiographic signal, the digitalization unit configured for sampling the filtered electrocardiographic signal, thus obtaining a digitalized electrocardiographic signal;

a data interface unit electrically connected to the digitalization unit, in such a way to receive the digitalized electrocardiographic signal, the data interface unit configured for making available the digitalized electrocardiographic signal,

wherein the two right and left side portions comprise a lower conductive surface electrically connected to the acquisition unit and arranged on a base surface, so that the patient, arranging the device on both the own legs while sitting, can bring the hand palms into contact with the upper conductive surfaces, i.e. with the electrically conductive above indicated surfaces which serve as acquisition electrodes, and can bring the lower conductive surface into contact with the skin of the legs.

[0032] According to a further aspect of the invention, a device is provided for carrying out an electrocardiographic examination of a patient, the device comprising:

an acquisition unit electrically connected to the conductive surfaces, in such a way to receive a raw electrocardiographic signal, the acquisition unit configured for filtering the raw electrocardiographic signal within a predetermined passband, thus obtaining a filtered electrocardiographic signal;

a digitalization unit electrically connected to the acquisition unit, in such a way to receive the filtered electrocardiographic signal, the digitalization unit configured for sampling the raw electrocardiographic signal, thus obtaining a digitalized electrocardiographic signal;

wherein said passband has a passband lower limit set between 0.2 and 1 Hz, in particular between 0.4 and 0.8 Hz, in particular said lower limit value is close to 0.5 Hz, and wherein said passband has a passband upper limit set between 35 and 45 Hz, in particular said upper limit is about to 40 Hz.

Brief description of the drawings

[0033] Further characteristics and advantages of the electrocardiograph according to the present invention will be made clearer by the following description of its exemplary embodiments, exemplifying but not limitative, with reference to the attached drawings, in which:

- Figs. 1A and 1 B are perspective plan views from the above and from below of a device according to a first exemplary embodiment of the invention;

- Fig. 2 is a perspective view of the device shown in Figs. 1A and 1 B, in use by a user;

- Fig. 3 is an elevation side view of the device shown in Fig. 2;

- Figs. 4A and 4B are perspective views from the above and from below of a device according to a second exemplary embodiment of the invention;

- Figs. 5A and 5B are perspective views from the above and from below of a device according to a third exemplary embodiment of the invention;

- Fig. 6 is a perspective view of the device shown in Figs. 5A and 5B, in use by a user;

- Figs. 7A and 7B are perspective views from the above and from below of a device according to a fourth exemplary embodiment of the invention;

- Fig. 8 is a block diagram of the device according to the invention;

- Fig. 9 is a block diagram of the ECG signal acquisition unit or front-end unit of a device, according to the invention, for carrying out a single-lead electrocardiogram examination;

- Fig. 10 is a block diagram of the ECG signal acquisition unit of a device, according to the invention, for carrying out a multiple-lead electrocardiogram examination, in particular a 6-lead ECG;

- Fig. 11 is a block diagram of the device according to the invention like the diagrammatical view of Fig. 8, with more details;

- Fig. 12 is a flow-sheet of a possible exemplary embodiment of the firmware of the device, in an exemplary embodiment thereof;

- Fig. 13 is a flow-sheet of an alternative exemplary embodiment of the firmware of the device; - Fig. 14 shows a plot of a patient's single-lead ECG recording, obtained by the device according to the invention, and a plot of the first lead ECG obtained at the same time from the same patient by a professional electrocardiograph of known type;

- Fig. 15 shows the two plots of Fig. 14 superimposed to each other, along with plots relating to other lead portion obtained at the same time by the professional electrocardiograph.

Description of a preferred exemplary embodiment

[0034] With reference to Figs. 1A and 1 B, an electrocardiographic device 30 is described according to a first exemplary embodiment of the invention, comprising a central portion 31 and two right and left side portions 33, wherein each portion has a base surface 36 and two conductive surfaces 1 ,3 opposite to base surface 36. Conductive surfaces 1 ,3 are intended for working as acquisition electrodes of electrocardiographic device 30, i.e. they are intended for coming into contact with a patient's right and left hands 98 (Fig. 2), arranged on respective side portions 33, in order to carry out an electrocardiographic examination of the patient. Acquisition electrodes 1 ,3 are dry electrodes, in other words no electrolytic gel is needed between acquisition electrodes 1 ,3 and the patient's hands 98. At side portions 33, i.e. at acquisition electrodes 1 ,3, device 30 has a height D set between 1 cm and 8 cm, which is therefore also the distance between base surface 36 and the surface of acquisition electrodes 1 ,3 on each side portion 33.

[0035] This height allows the patient 99 cause the palm 97 of hands 98 to bear on acquisition electrodes 1 ,3, and to keep at the same time the proximal portion 98' and the distal portion 98" of hands 98 in contact with a support plane 28, on which electrocardiographic device 30 is arranged, at opposite sides with respect to acquisition electrodes 1 ,3, which minimizes the muscle tension to keep palm 97 of hands 98 in contact with acquisition electrodes 1 ,3.

[0036] In the exemplary embodiment of Figs. 1A and 1 B, device 30 has the shape of an elongated box 32, in particular the shape of a thin parallelepiped, on the top face of which acquisition electrodes 1 ,3 are arranged. Box 32 has preferably a top surface size set between 25 x 4 cm and 35 x 7 cm, in particular a top surface size of about 30 cm x 5 cm, and a height D of about 2.5 cm. In this case, right and left metal electrodes 1 ,3 preferably have a rectangular shape, whose size is set between 1 cm x 8 cm and 3 cm x 12 cm, in particular a size of about 2 cm x 10 cm.

[0037] Box 32 includes parts for operating electrocardiographic device 30, which are diagrammatically shown in Fig. 8, in a possible exemplary embodiment, and which are described more in detail hereinafter, besides a housing for at least one battery, in order to electrically supply device 30. Box 32, preferably at its upper surface, in particular at central portion 31 of device 30, provides user interface elements comprising at least one element selected among a power key 5, or an equivalent device, a plurality of warning lights 6, 7, 8, selected among a power light 6, a ready light 7 and a heart rate light 8, whose operation is described more in detail hereinafter. A progress indication display 9 can also be provided among the user interface elements for indicating the electrocardiographic data progress acquisition, preferably a liquid-crystal display, in which an area can be provided for numerically indicating the heart rate. A socket 10 is also provided, for example on a side face of box 32, preferably a USB or micro- USB connector, or also an SD-card connector for a possible cable connection, in order to transfer data, in particular in order to store data on a removable data storage unit, such as a USB key or a SD-card, for programming device 30 and recharging the battery or the batteries.

[0038] Figs. 4A and 4B show an electrocardiographic device 40 according to a second exemplary embodiment of the invention, which differs from electrocardiographic device 30 of Figs. 1A,1 B in that it comprises further conductive surfaces 2,4 that are parallel to acquisition electrodes 1 ,3 and that are configured as common mode electrodes of electrocardiographic device 40. Conductive surfaces 2,4 are electrically connected to each other, in particular a single continuous conductive surface can be provided between right and left side portions 33. This way, hand palm 97 of each patient's 99 hand 98 comes into contact with both respective electrodes 1 ,3, and with a portion of common mode electrodes 2,4.

[0039] Electrocardiographic devices 30,40 allow to carry out a single- lead electrocardiographic examination, as described more in detail hereinafter. [0040] Figs. 5A and 5B show an electrocardiographic device 50, according to a third exemplary embodiment of the invention, which differs from electrocardiographic device 30 of Figs. 1A, 1 B in that it comprises two further conductive surfaces 2',4', that are arranged on base surface 36, i.e. opposite to acquisition electrodes 1 ,3. Electrocardiographic device 50 is configured to be arranged with its base surface 36 in contact with the legs 39 of a sitting patient 99, who is submitted to an electrocardiographic examination, close to the knees, as shown in Fig. 6, arranging acquisition electrodes 1 ,3 facing upwards and further conductive surfaces 2',4' facing downwards, i.e. arranged on the patient's legs 39. More in detail, conductive surface 4' serves as common mode electrode of electrocardiographic device 50, and, in use, is preferably arranged in contact with the patient's right leg, as required by the standards concerning the common mode electrode, while conductive surface 2' is a further acquisition electrode for receiving the cardiac signal, in addition to acquisition electrodes 1 ,3, and is preferably arranged in contact with the patient's left leg, as it is still shown in Fig. 6. Even in this case, the size, in particular the height of electrocardiographic device 50, allows to keep hand palm 97 of each patient's 99 hand 98 in contact with acquisition electrodes 1 ,3, thus substantially suppressing any muscle tension while causing the hands to bear on the device.

[0041] Due to third acquisition electrode 2', electrocardiographic device 50 makes it possible to carry out multiple-lead electrocardiographic examinations (Fig. 10), in particular up to a 6-lead ECG, as described more in detail hereinafter.

[0042] Figs. 7A and 7B show an electrocardiographic device 60 according to a fourth exemplary embodiment of the invention, which differs from electrocardiographic device 30 of Figs. 3A, 3B in that it comprises, preferably instead of display 9, a housing 29 for connecting an advanced telephone device such as a smartphone to be used as connection unit to establish a connection with the web, serving at the same time as data forwarding unit (Fig. 8) and/or as a gateway.

[0043] Devices 30, 40, 50 or 60 according to an exemplary embodiment of the invention are diagrammatically shown by the block diagrams of Fig. 8 and of Fig. 11. The device has a battery 11 electrically connected with a power supply unit 12 of the whole circuit, and with a reference voltage generation unit 13, which is required for operating the components of the device.

[0044] In Fig. 8, electrodes ,2, 3, 4, 2', 4', whichever is present, are globally indicated as an electrode unit 14. Electrode unit 14 is configured for collecting a raw electric signal, containing an electrocardiographic signal, from the patient's hands in the case of devices 30, 40 and 60, or from the patient's hands and legs 39, in the case of device 50, which is the voltage between acquisition electrodes or between each physical electrode 1 ,2,3 and a virtual electrode, the so-called Wilson electrode, in a configuration of device 50 to carry out a 6-lead ECG examination, as described above.

[0045] Electrode unit 14 can be electrically connected with a front-end unit, i.e. acquisition unit 25, for acquiring the raw electric signal, so that acquisition unit 25 receives the raw electric signal for analogically pre- amplifying, filtering, amplifying and conditioning it, as described more in detail hereinafter.

[0046] A possible embodiment of acquisition unit 25 is diagrammatically shown in the block diagram of Fig. 11. It comprises a pre-amplification unit 15 that is electrically connected with electrode unit 14 for preliminarily amplifying the raw electric signal, thus obtaining a pre-amplified raw signal. Acquisition unit 25 also comprises a filtering unit 16 that is electrically connected with pre-amplification unit 15, so as to receive the pre-amplified raw signal from the latter. Filtering unit 16 comprises essentially a passband filter that is configured for filtering away or for minimizing the noise from the pre-amplified electric signal, thus obtaining a filtered electric signal, in particular for removing electric signal components related to some patient's physiological activities, or related to myoelectric signals, and to other noise factors.

[0047] In particular, the passband filter can have a passband with a passband lower limit of about 0.5 Hz, so as to substantially exclude possible residual artifacts due to the contact of the hands with the device, as well as to the above-indicated causes. In particular, the passband filter has a 0.5÷40 Hz passband, which corresponds to a passband of a professional electrocardiograph when operating in the monitoring mode.

[0048] Front-end unit 25 can also comprise an amplifying and conditioning unit 17 electrically connected to filtering unit 16, so as to receive the filtered signal from the latter, which is configured for converting the filtered signal into a conditioned signal that can be accepted by a signal digitalization unit 18, as described hereinafter.

[0049] In Figs. 9 and 10, another representation is given of a possible signal acquisition unit 25, in an electrocardiographic device configured for carrying out single-lead electrocardiographic examinations (Fig. 9), such as electrocardiographic devices 30, 40, 60, or for carrying out multiple-lead electrocardiographic examinations (Fig. 10), in particular up to 6-lead ECG examinations, such as electrocardiographic device 50. More in detail, signal acquisition unit 25 of Fig. 9 comprises a pre-amplifier 72 that is electrically connected to electrodes 1 and 3 which, in use, are kept in contact with a patient's left and right hand 99, respectively, and preferably also comprises a common mode electrode 4, conventionally shown as an electrode in contact with the patient's right leg, connected to a buffer or inverting amplifier 77 for controlling the right leg electrode. Therefore, the diagrammatical view of Fig. 9 relates more precisely to electrocardiographic device 40 of Figs. 4A and 4B or to device 50 of Figs. 5A and 5B in a use configuration for carrying out a single-lead electrocardiographic examination, in which electrode 2' is not connected or is absent, and electrode 4', in use, is kept in contact with the right leg, and is used as common mode electrode. Signal acquisition unit 25 also comprises a passband filter 74 that is electrically connected to pre-amplifier 72, so as to receive the pre-amplified raw signal, and that is configured for filtering the pre-amplified raw signal within a predetermined passband, thus obtaining a filtered signal, and also comprises an amplifier 76 that is electrically connected to filter 74, so as to receive the filtered signal, and that is configured for converting the filtered signal into a conditioned signal that can be accepted by subsequent signal digitalization unit 18 (Fig. 8).

[0050] Acquisition unit 25 of Fig. 10 can comprise an electrocardiographic signal inlet unit 70 electrically connected to electrodes 1 and 3 which, in use, are kept in contact with patient's 99 left hand and right hand, respectively, electrically connected to electrode 2' which, in use, is kept in contact with a patient's 99 leg, typically the left leg, and electrically connected to a common mode electrode 4 which, in use, is kept in contact with the other patient's 99 leg, typically with the right leg. Inlet unit 70 comprises a lead selector means and a pre-amplifier, for connecting electrodes 1 , 2', 3, so as to measure the voltage between electrodes 1 and 2'; 2' and 3; 3 and 1 , as well as between each of electrodes 1 , 2' and 3 with respect to Wilson virtual electrode, up to an arrangement for a 6-leads ECG recording. Acquisition unit 25 also comprises six circuit branches 71·, where i = 1..6. Each circuit branch 71 j is formed the same way as a portion 71 of front-end unit 25 of Fig. 9, comprising a filter 74,, an amplifier 76,, and processes an amplified raw signal related to the first, the second,., the sixth electrocardiographic lead.

[0051] Still with reference to Fig. 8, device 30, 40, 50 or 60 comprises an electric signal digitalization unit 18 connected to signal acquisition unit 25, so as to receive the conditioned signal, and configured for digitalizing and processing the conditioned signal, thus obtaining an electrocardiographic signal. In the exemplary embodiments of Figs. 9 and 10, digital-to-analog converters (DAC) 78 and 78; are shown, made as components external to signal digitalization unit 18 of which they can be a part, as an alternative.

[0052] As shown more in detail in Fig. 11 , a data interface unit 22, in particular a Bluetooth connection device, can be electrically connected to microcontroller 18, said data interface unit configured for connecting with a gateway, not shown, according to the procedure described hereinafter, and to allow a communication with the gateway, in particular in order to transfer the electrocardiographic signal to the gateway.

[0053] The gateway can be any device that is configured for receiving data from the ECG sensor, through a cable or wireless connection, in particular through a Bluetooth connection, and that is configured for forwarding these data to their final destination, preferably via Internet or via a dedicated data network. For instance, the gateway can be a smartphone or a tablet having a special application, or a PC device or a specifically designed device.

[0054] Microcontroller 18 is also electrically connected to the elements of a user interface 26 that include, in particular, at least one visible element 20 for notifying the status of device 30, 40, 50 or 60, for instance a LED light, selected among a power signalling element 6 (see, for instance, Figs. 3A and 3B) and/or of a flat battery signalling element, a ready device signalling element 7, a heart rate signalling element 8, and that also include a display unit or LCD display 9 for showing the electrocardiographic acquisition progress.

[0055] With reference to Fig. 12, the operation of the electrocardiographic device is now described according to a possible exemplary embodiment of the firmware of the device, in which a signal processing unit 19 is configured for carrying out the steps that are shown as blocks in Fig. 12 and that are indicated within parentheses hereinafter. The device is turned on by pushing power key 5. Then, according to a predetermined operation mode, device 40 tries to connect to a designed gateway, or waits for a connection request from the gateway (101 ). Once connected to the gateway, the device waits for a "start" command from the gateway (102) in order to start the acquisition of an ECG recording. Power LED 6 on (Fig. 4A) means that the electrocardiographic device is turned on, while ready device LED 7 lights up (103) when the device has received the "start" command and is ready to acquire the ECG signal. Once ready device LED 7 is turned on, and once the user has caused one hand to bear on electrodes 1 ,2 and the other hand to bear on electrodes 3,4, and once a valid ECG signal has been detected, the device starts acquiring the ECG signal and calculating the hearth rate (104), while sending data to the gateway through data interface unit 22, in particular through a Bluetooth connection device. During the acquisition, heart rate LED 8 is turned on (112) in coincidence with any peak of the electrocardiographic recording, therefore it blinks at the same frequency as the heart rate, which also indicates that the acquisition is in progress. At the same time, the state of progress indicator display 9 is updated. Moreover, the signal is acquired and processed for calculating the hearth rate (113) and the validity of the signal (114) is checked on this basis.

[0056] Signal processing unit 19, in particular a microcontroller, is provided with a computation and comparison means for classifying the signal as a reliable signal or as a not reliable signal (105). If, during the acquisition, microcontroller 19 considers the detected signal as a not reliable signal, the device notifies to the gateway that the previously sent electrocardiogram recording is not valid, in order to avoid any wrong interpretation. On the contrary, if microcontroller 19 classifies the detected signal as a reliable signal, it starts counting the acquisition time (106) and preferably also checks the battery level (107). In this case, the battery level, with respect to a predetermined threshold, is indicated by a flag (108), which is sent to the gateway along with the samples of the ECG recording and of the hearth rate (109) in a same data package. In this connection, if the battery level is so low that it can threaten the reliability of the ECG examination, the device notifies the gateway that the current recording is not valid, and preferably notifies the status of "flat battery" also to the user, for example by causing power LED light 6 to blink.

[0057] The end of the acquisition (1 10) occurs after a predetermined time, defined by the gateway and contained in the "start" command, and is notified to the user through progress indicator display 9, which displays the progress of the acquisition. Optionally, a display element can be provided for displaying the hearth rate as calculated, in particular the hearth rate can be indicated in the same window of progress indicator display 9. At the end of the acquisition, user 99 can remove the hands from the device and shut down the latter by key 5, which is also configured for turning off the device, or can wait for the device to automatically shut down, after a given inactivity time, for example about some minutes.

[0058] According to another possible exemplary embodiment of the firmware, in an initial configuration the data interface unit of the device is not coupled with any gateway.

[0059] If the use of a gateway is provided, when the device is turned on for the first time, the designed gateway searches the electrocardiographic device and sends a "pairing" request by using a predetermined PIN code. Once the pairing procedure has come to an end, the device searches the gateway, or the gateway searches the device in order to request the connection, according to whether operation mode of the data interface unit is set as "slave" or as "master", respectively. By pushing one of two hidden "master" or "slave" configuration keys 23 (Fig. 1 1 ) when turning on device 40, the latter becomes configured in one of the two operation modes, respectively, and cancels the list of the paired gateways. In this case, the pairing procedure must be repeated.

[0060] Once the power key has been pressed, the microcontroller is initialized and waits for the Bluetooth unit to notify that a connection with the gateway has been established. Once the connection has been established, the microcontroller becomes set in a receiving mode, and waits for the "start" command from the gateway, said command containing, as an argument, the duration of the ECG recording to be acquired. Upon reception of the "start" command, the microcontroller lights up the LED 7 for notifying that it is ready for the acquisition, and starts converting and processing the detected signal. As soon as the signal is classified as a valid signal, the acquisition time count begins and an ECG recording is sent to the gateway real time through the Bluetooth connection. While processing the signal, the program executed by the microcontroller calculates the hearth rate starting from the ECG recording and delivers the values thereof to the gateway, briefly lighting up LED 8 whenever a peak value is detected in the signal. If, during the acquisition, a portion of the detected signal is classified as invalid, the invalidity of the recording is notified in the corresponding data packages that are sent to the gateway.

[0061] During the acquisition, the microcontroller controls a LCD display on which an acquisition progress indicator and value of the calculated hearth rate are shown. At the end of the acquisition of the electrocardiogram, the microcontroller sends a "stop" package to the gateway, and turns back into a stand-by mode.

[0062] If the Bluetooth connection breaks down while the program is being executed, the microcontroller immediately stops waiting, converting, controlling and sending data, and turns back to the initial state, in which it is available for a new connection.

At the beginning of each acquisition, as the first data package, the microcontroller sends a battery level charge value to the gateway. If the battery level is lower than a given threshold value, and therefore it is too low for ensuring a correct electrocardiogram examination, the firmware causes LED 6 to blink, in order to notify the flat battery discharge state and communicates the invalidity of each sent packages to the gateway, by a special flag.

[0063] According to a further possible exemplary embodiment of the firmware of the device, signal processing unit 19 is configured for carrying out the steps that are shown as blocks in Fig. 13 and that are indicated within parentheses hereinafter. Fig. 13 applies regardless of whether a gateway is present or not. If a gateway is not provided, firmware 19 checks if a pairing request is in progress or not, if that is the case it responds to the request (202) whereas, if that is not the case, it initializes the device (203) and starts sampling the analog signals received from front-end unit 28 (204), cyclically checking whether the contact with the patient is present (207) and whether the ECG is valid, for example by verifying if the hearth rate value is a possible hearth rate value (209), showing it on the display (210) if that is the case, or performing a further sampling (204), i.e. repeating the above described operation cycle.

[0064] A check for the presence of a connection to a gateway (21 1 ) can take place only subsequently.

[0065] If a connection to a gateway is not present, signal processing unit 19 carries out a further sampling (204) and repeats the above-described operation cycle. Still in the same case, the electrocardiogram recording, instead of being transmitted to the gateway, can be stored into a memory unit (not shown), for example into a . flash memory, an SD-card, a USB key and the like, and can be sent or delivered later to a doctor.

[0066] On the contrary, if a connection to a gateway is present, signal processing unit 19 checks whether a transmission mode is in progress (212). If this is in progress, new data are added to a data package being formed (215), periodically checking (216) whether the latter is complete or not (216). Once completed, signal processing unit 19 sends this data package to the gateway (217), possibly updates and shows the progress bar of display 9 (218) always checking whether the transmission of the recording has come to its end (219). If that is the case, the device leaves the transmission mode (220). If that is not the case, signal processing unit 19 carries out a further sampling (204), repeating the above described operation cycle, as it happens whenever a package has been completed (216).

[0067] If no transmission is in progress (212), signal processing unit 19 checks whether a start command is present (213) and, if that is the case, it carries out this command (214), otherwise it can notify its own "ready to transmit" status (221 ) and carries out a further sampling (204), repeating the above described operation cycle.

[0068] Figs. 14 and 15 compare a plot 91 of a single-lead electrocardiogram recording, obtained by a device according to an exemplary embodiment of the invention, and a plot 90 obtained from the same patient during the same time by a professional electrocardiographic device. More in detail, Fig. 14 shows electrocardiogram plot 91 and, beside it, a first lead plot 90 obtained during the same time by the professional electrocardiographic device. On the other hand, Fig. 15 shows two plots 90,91 of Fig. 14 superimposed to each other, along with distinct ECG lead plots 92, 93 obtained during the same time by the professional electrocardiograph. The superimposed plots confirm the conclusion, which can also be drawn from Fig. 14, of a substantial identity of single-lead electrocardiogram recording plot 91 , obtained by the device according to the intention, and of the first lead electrocardiogram recording plot 90 obtained by the professional device.

[0069] The foregoing description exemplary specific embodiments of the device according to the invention and of its mode of use, will so fully reveal the invention according to the conceptual point of view, so that others, by applying current knowledge, will be able to modify and/or adapt in various applications the specific exemplary embodiments without further research and without parting from the invention, and, accordingly, it is meant that such adaptations and modifications will have to be considered as equivalent to the specific embodiments. The means and the materials to realise the different functions described herein could have a different nature without, for this reason, departing from the field of the invention. It is meant that the phraseology or terminology used are descriptive and not limitative.

Claims

1. A device (30,40,50,60) for carrying out an electrocardiographic examination of a patient (99), said device (30,40,50,60) comprising:

a central portion (31) and two right and left side portions (33), said side portions having respective conductive surfaces (1 ,3), said conductive surfaces (1 ,3) of said side portions (33) configured as respective acquisition electrodes for receiving a raw electrocardiographic signal from said patient's (99) respective hands (98);

an acquisition unit (25) electrically connected to said conductive surfaces (1 ,3), so as to receive said raw electrocardiographic signal, said acquisition unit (25) configured for filtering said raw electrocardiographic signal within a predetermined passband, thus obtaining a filtered electrocardiographic signal;

a digitalization unit (18) electrically connected to said acquisition unit (25), so as to receive said filtered electrocardiographic signal, said digitalization unit (18) configured for sampling said filtered electrocardiographic signal, thus obtaining a digitalized electrocardiographic signal;

a data interface unit (22) electrically connected to said digitalization unit (18), so ^ as to receive said digitalized electrocardiographic signal, said data interface unit (22) configured for making said digitalized electrocardiographic signal available;

characterized in that

said side portions (33) have a base surface (36) that is opposite to said conductive surfaces (1 ,3) and that is configured to be arranged on a plane, said side portions having a height (D) between said base surface (36) and said conductive surfaces (1 ,3) set between 1 cm and 8 cm, said side portions having a front edge (37) arranged to be in a distal position with respect to said patient (99), said front edge arranged in such a way that the distance between said front edge (37) and said conductive surfaces (1 ,3) is shorter than a predetermined value (L), in such a way that said patient (99), arranging said bases (36) on said plane (28), can cause the hand palm (97) of the respective hands (98) to bear on said right and left side portions (33), maintaining said hand palm (97) in contact with said conductive surfaces (1 ,3) and at the same time assisting the fingers (98") of said hands (98) to rest on said plane (28).

2. An electrocardiographic device (30,40,50,60) according to claim 1 , wherein said passband has a passband lower limit set between 0.2 and 1 Hz.

3. An electrocardiographic device (30,40,50,60) according to claim 1 , wherein said passband has a passband lower limit set between 0.4 and 0.8 Hz, in particular said lower limit value is about 0.5 Hz.

4. An electrocardiographic device (30,40,50,60) according to claim 1 , wherein said passband has a passband upper limit set between 35 and 45 Hz, in particular said upper limit is about 40 Hz.

5. An electrocardiographic device (30,40,50,60) according to claim 1 , wherein said height (D) is set between 2 and 4 cm, preferably between 2.5 and 3.5 cm.

6. An electrocardiographic device (30,40,50,60) according to claim 1 , wherein said distance (L) is shorter than 5 cm, preferably shorter than 2 cm.

7. An electrocardiographic device (40) according to claim 1 , wherein said conductive surfaces (1 ,3) are first conductive surfaces (1 ,3), and said two right and left side portions (33) comprise a further conductive surface (2,4) adjacent to said first conductive surfaces (13) and electrically connected to said acquisition unit (25), wherein said further conductive surface (2,4) is configured as a common mode electrode of said electrocardiographic device (40).

8. An electrocardiographic device (40) according to claim 5, wherein said further conductive surface (2,4) configured as a common mode electrode comprises two conductive portions (2,4) of said further right and left conductive surface that are arranged on said right and left side portions (33) of said device (40), respectively, wherein said two conductive portions (2,4) are electrically interconnected.

9. An electrocardiographic device (50) according to the previous claims, wherein said conductive surfaces (1 ,3) are upper conductive surfaces (1 ,3), and said two right and left side portions (33) comprise a lower conductive surface (2',4') electrically connected to said acquisition unit (25), wherein said lower conductive surface (2',4') is arranged on said base surface (36), so that said patient, by arranging said device on both the own legs (39) while sitting, can bring the hand palm into contact with said upper conductive surfaces (1 ,3) and can bring said lower conductive surface (2',4') in contact with the legs (39).

A device (30,40,50,60) for carrying out an electrocardiographic examination of a patient (99), said device (30,40,50,60) comprising:

- an acquisition unit (25) electrically connected to said conductive surfaces (1 ,3), so as to receive said raw electrocardiographic signal, said acquisition unit (25) configured for filtering said raw electrocardiographic signal within a predetermined passband, thus obtaining a filtered electrocardiographic signal;

- a digitalization unit (18) electrically connected to said acquisition unit (25) so as to receive said filtered electrocardiographic signal, said digitalization unit (18) configured for sampling said raw electrocardiographic signal, thus obtaining a digitalized electrocardiographic signal;

a data interface unit (22) electrically connected to said digitalization unit (18), so as to receive said digitalized electrocardiographic signal, said data interface unit (22) configured for making said digitalized electrocardiographic signal available;

characterized in that

said conductive surfaces (1 ,3) are upper conductive surfaces (1 ,3), and said two right and left side portions (33) comprise a lower conductive surface (2',4') electrically connected to said acquisition unit (25), wherein said lower conductive surface (2',4') is arranged on said base surface (36), so that said patient, arranging said device on both the own legs (39) while sitting, can bring the hand palm into contact with said upper conductive surfaces (1 ,3) and can bring said lower conductive surface (2',4') in contact with the skin of the legs (39).

11. An electrocardiographic device (50) according to claim 9 or 10, wherein said lower conductive surface comprises a surface (4') configured as a common mode electrode of said electrocardiographic device (50).

12. An electrocardiographic device (50) according to claim 11 , wherein said surface (4') configured as a common mode electrode is arranged on said base surface (36) of said right portion (33) of said device (50).

13. An electrocardiographic device (50) according to claim 9 or 10, wherein said lower conductive surface comprises a surface (2') configured as a further acquisition electrode of said electrocardiographic device (50), and said acquisition unit (25) comprises an electrocardiographic signal inlet unit (70), comprising a lead selector means for bringing the electrodes (1 , 2', 3) into electric contact with said acquisition unit (25), in order to measure the voltage between said electrodes according to a plurality of ECG leads.

14. An electrocardiographic device (30,40,50,60) according to claim 1 or 10, comprising an elongated container (32) that has a height equal to said distance (D), wherein a surface (34) of said elongated container comprises said conductive surfaces (1 ,3), wherein an opposite surface of said container comprises said base surface (36).

15. An electrocardiographic device according to claim 1 or 10, wherein said container has a parallelepiped shape, the top surface size of which is set between 25 x 4 cm and 35 x 7 cm.

16. An electrocardiographic device (40) according to claim 1 or 10, wherein said conductive surfaces (1 ,3) comprise two right (1) and left (3) rectangular electrodes that have a size set between 1x8 cm and 3x12 cm.

17. An electrocardiographic device according to claim 1 or 10, wherein said container has said central portion (31) from whose sides said side portions (33) extend integrally.

18. An electrocardiographic device (30,40,50,60) according to claim 1 or 10, wherein a user interface unit is provided comprising at least one interface element selected from the group consisting of:

- a power key (5);

a power light (6); a ready light (7);

a heart rate light (8);

a display (9) showing the acquisition progress of the electrocardiographic data.

19. An electrocardiographic device (30,40,50,60) according to claim 1 or 10, wherein said data interface unit comprises a wireless data interface unit (22) configured for transferring said digitalized electrocardiographic signal to a local gateway.

20. An electrocardiographic device (30,40,50,60) according to claim 19, wherein said data interface unit (22) comprises a Bluetooth device.

21. An electrocardiographic device (60) according to claim 1 or 10, wherein said data interface unit is configured to be connected to a portable device, such as an advanced telephone device selected between a tablet and a smartphone.

22. An electrocardiographic device (60) according to claim 21 , comprising a housing (29) for inserting said advanced telephone device.

23. An electrocardiographic device (60) according to claim 22, wherein said housing (29) for inserting said advanced telephone device is made in said central portion (31) of said device.

24. A system (60') for carrying out an electrocardiographic examination of a patient (99), said system (60') comprising:

a electrocardiographic device (60) according to the previous claims; an advanced telephone device.

25. A device (30,40,50,60) for carrying out an electrocardiographic examination of a patient (99), said device (30,40,50,60) comprising:

a data interface unit (22) electrically connected to said digitalization unit (18), so as to receive said digitalized electrocardiographic signal, said data interface unit (22) configured for providing said digitalized electrocardiographic signal so as it can be drawn;

characterized in that

said passband has a passband lower limit set between 0.2 and 1 Hz, in particular between 0.4 and 0.8 Hz, in particular said lower limit value is close to 0.5 Hz, and wherein said passband has a passband upper limit set between 35 and 45 Hz, in particular said upper limit is close to 40 Hz.