DETECTOR SYSTEM AND METHOD FOR DETECTING Worsening Depression of Cardiac Function - Patent application

Abstract

A detector system for non-invasively detecting worsening cardiac decline comprises a sensor (102), e.g., a gyroscope, configured to generate a measurement signal when in motion-sensing relationship with a jugular vein (105) of an individual. The detector system comprises a processing system (101) configured to receive the measurement signal, and a memory system (103) communicatively connected to the processing system. Since changes in the behavior of the jugular vein pressure may indicate a progression of cardiac decline, the processing system is configured to compare first data stored in the memory system, the first data being based on an earlier generated measurement signal, with second data being based on a later generated measurement signal, and form indicator data indicative of worsening cardiac decline based on a comparison of the first data and the second data.

Description

[Technical field]

[0001] The present disclosure relates to a detector system and a detection method for detecting worsening cardiac decline, and further to a computer program for detecting worsening cardiac decline. [Background technology]

[0002] Abnormalities that may occur in the cardiovascular system can gradually deteriorate an individual's health if not diagnosed and properly treated and / or improved. For example, pulmonary hypertension (PAH) is often an early indicator of a worsening phase of cardiac decline, which occurs on average 3-4 weeks after the onset of pulmonary hypertension. In many cases, pulmonary hypertension can predict the worsening phase of cardiac decline at a very early stage, so that traditional signs of cardiac decline, such as weight gain or elevated blood pressure, are usually not present. Cardiac decline diagnosed at an early stage can often be treated and / or improved, thereby significantly reducing mortality and the need for hospitalization.

[0003] Abbott Laboratories, Chicago, USA, has developed a system for detecting worsening cardiac decline. The system comprises a micromechanical sensor and a receiver for receiving measurement data from the micromechanical sensor. The micromechanical sensor is placed in the pulmonary artery through the right side of the heart. Thus, the Abbott Laboratories method for detecting worsening cardiac decline is an invasive method. The receiver of the Abbott Laboratories system can be placed, for example, on the patient's bed. When the patient lies on the bed, the micromechanical sensor transmits measurement data via the receiver to a cloud service. This measurement data may indicate the above-mentioned pulmonary hypertension "PAH" and is often an early sign of a worsening stage of cardiac decline.

[0004] The invasive methods described above have obvious risks associated with the need for invasive surgery on the human body. Moreover, some invasive methods can only be used during surgery. On the other hand, non-invasive methods based on Doppler ultrasound measurements require expensive equipment and skilled and experienced examination staff. Therefore, there is a need for a non-invasive system and method for detecting the deterioration of cardiac function. Summary of the Invention [Means for solving the problem]

[0005] overview The following presents a simplified summary in order to provide a basic understanding of some aspects of various invention embodiments. This summary is not an extensive overview of the invention, and is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. The following summary merely presents some concepts of the invention in a simplified form as a prelude to a more detailed description of example embodiments of the invention.

[0006] In this document, the word "geometric" used as a prefix means a geometric concept that is not necessarily part of a physical object, such as a geometric point, a straight or curved geometric line, a geometric plane, a non-planar geometric surface, a geometric space, or any other geometric entity of zero, one, two or three dimensions.

[0007] According to the present invention, a novel detector system for non-invasively detecting worsening cardiac dysfunction is provided. The detector system according to the present invention comprises: a processing system configured to receive the measurement signal; a sensor, e.g., a gyroscope, configured to generate a measurement signal when in motion sensing relationship with the individual's jugular vein "JV" (Latin vena jugularis); A memory system communicatively coupled to the processing system.

[0008] The processing system comparing first data stored in the memory system, the first data being based on an earlier generated first portion of the measurement signal, with second data being based on a later generated second portion of the measurement signal; Forming index data indicative of worsening cardiac dysfunction based on a comparison between the first data and the second data. It is structured as follows.

[0009] Since the jugular vein is directly connected to the right atrium of the heart, the jugular vein pressure variations are caused by changes in blood flow and pressure changes due to filling and contraction of the right atrium and right ventricle of the heart. This opens the door to non-invasive testing of the right side of the heart, i.e. the right ventricle and right atrium, based on changes in the behavior of the jugular vein pressure. In the system according to the invention, possible changes in the behavior of the jugular vein pressure are stored in a memory system and detected by comparing first data based on an earlier generated part of the measurement signal with second data based on a later generated part of the measurement signal. In addition to the above-mentioned first and second parts of the measurement signal, third, fourth, etc. parts of the measurement signal can be generated, so that the development of the state of cardiac depression can be monitored over time.

[0010] The above mentioned sensor is advantageously a rotation sensor applied to the individual's skin and in a motion-sensitive relationship with the individual's jugular vein. The rotation sensor is advantageously arranged such that one end of the rotation sensor is closer to the jugular vein than the other end of the rotation sensor. Fluctuations in the jugular vein pressure therefore cause more movement at the first mentioned end of the rotation sensor than at the last mentioned end of the rotation sensor, this difference appearing as a rotational movement of the rotation sensor. A movement that is independent of the jugular vein pressure and has substantially the same amplitude and direction over the entire skin area covered by the rotation sensor does not cause a significant rotational movement of the rotation sensor, but only a translational movement, so that this movement does not give rise to a significant signal component in the output signal of the rotation sensor. A rotation sensor that measures rotation is therefore less sensitive to many movements that are not related to jugular vein pressure fluctuations than, for example, an acceleration sensor that measures a translational movement.

[0011] The present invention also provides a novel method for non-invasively detecting worsening cardiac dysfunction. The method according to the present invention comprises: generating a measurement signal with a sensor in motion sensitive relationship with the individual's jugular vein; comparing first data stored in a memory system and based on an earlier generated first portion of the measurement signal with second data based on a later generated second portion of the measurement signal; and forming indicator data indicative of worsening cardiac decline based on a comparison of the first data and the second data.

[0012] According to the invention there is also provided a novel computer program for controlling a programmable data processing system to detect worsening cardiac depression. The computer program comprises: receiving a measurement signal from a sensor adapted to generate a measurement signal when in motion sensitive relationship with a jugular vein of the individual; storing, in a memory system, first data based on a previously generated first portion of the measurement signal; comparing the first data to second data based on a subsequently generated second portion of the measurement signal; Forming index data indicative of worsening cardiac dysfunction based on a comparison between the first data and the second data. The present invention includes computer executable instructions for controlling the

[0013] According to the present invention there is also provided a novel computer program product, which comprises a non-volatile computer readable medium, such as a compact disc "CD", encoded with a computer program according to the present invention.

[0014] Exemplary and non-limiting embodiments are set forth in the accompanying dependent claims.

[0015] Various exemplary and non-limiting embodiments, both as to structure and method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific illustrative embodiments when read in conjunction with the accompanying drawings.

[0016] In this specification, the verbs "comprise" and "include" are used as open limitations which neither exclude nor require the presence of any unrecited features.

[0017] The features recited in the accompanying dependent claims are mutually freely combinable, unless expressly stated otherwise.

[0018] Furthermore, it will be understood that the use of the singular "a" or "an" throughout this specification does not exclude a plural.

[0019] Exemplary and non-limiting embodiments and their advantages are described in more detail below with reference to the accompanying drawings. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 illustrates a detector system for non-invasively detecting worsening cardiac decline according to an exemplary and non-limiting embodiment. [Figure 2a] FIG. 2a illustrates the functionality of a detector system for non-invasively detecting worsening cardiac decline according to an exemplary and non-limiting embodiment. [Figure 2b] FIG. 2b illustrates the functionality of a detector system according to an exemplary and non-limiting embodiment for non-invasively detecting worsening cardiac decline. [Diagram 3] FIG. 3 is an exemplary diagram showing a jugular venous pressure "JVP" waveform and an electrocardiogram "ECG" waveform to illustrate the functionality of a detector system according to an exemplary and non-limiting embodiment for non-invasively detecting worsening cardiac dysfunction. [Figure 4]FIG. 4 is a flow chart of a method for non-invasively detecting worsening cardiac decline, according to an exemplary and non-limiting embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Description of Exemplary and Non-Limiting Embodiments The specific examples provided in the following description should not be construed as limiting the scope and / or applicability of the appended claims. The lists and groups of examples provided herein are not exhaustive unless expressly stated.

[0022] FIG. 1 illustrates a detector system according to an exemplary and non-limiting embodiment for non-invasively detecting worsening cardiac decline. The detector system comprises a sensor 102 configured to generate a measurement signal when the sensor 102 is in a motion-sensitive relationship with a jugular vein 105 of an individual 111. In the detector system illustrated in FIG. 1, the sensor 102 is a rotation sensor, e.g., a gyroscope, configured to generate a measurement signal indicative of a rotation of the rotation sensor when the rotation sensor is applied to the skin 104 of the individual such that the rotation sensor is in a motion-sensitive relationship with the jugular vein 105 of the individual. However, it is also possible that the sensor is, for example, an optical sensor suitable for optically measuring the movement caused by the jugular vein 105 on the skin 104. In the portion 106 of FIG. 1, the direction perpendicular to the skin 104 is substantially parallel to the z-axis of the coordinate system 199. In this exemplary case, the sensor 102 is part of a device 107 that is applied to the skin 104 of the individual 111. The device 107 can be, for example, a mobile phone. The detector system comprises a processing system 101 configured to receive measurement signals from the sensor 102. Furthermore, the detector system comprises a memory system 103 communicatively connected to the processing system 101. In this exemplary case, the memory system 103 is implemented as a cloud service in an external data network 108.

[0023] Since the jugular vein 105 is directly connected to the right atrium of the heart, the variations in the jugular venous pressure "JVP" are caused by changes in blood flow and pressure caused by filling and contraction of the right atrium and right ventricle of the heart. This opens the door for non-invasive testing of the right side of the heart, i.e. the right ventricle and right atrium, based on changes in the behavior of the jugular venous pressure. To detect possible changes in the behavior of the jugular venous pressure, the processing system 101 is configured to compare first data stored in the memory system 103, the first data being based on an earlier generated first portion of the measurement signal, and second data being based on a later generated second portion of the measurement signal. Furthermore, the processing system 101 is configured to form indicator data indicative of worsening cardiac decline based on the comparison between the first data and the second data. The device 107 can, for example, comprise a display for presenting the indicator data to a user. The display is not shown in FIG. 1. It is also possible that the device is configured to transmit the indicator data to a data network 108. The above-mentioned first and second data can be defined in different ways based on the first and second parts of the measurement signal. Some examples are given below, but it should be noted that the present invention is not limited to the examples given below.

[0024] In the detection system according to the exemplary and non-limiting embodiment, the sensor 102 is a rotation sensor configured to measure the angular velocity ω of the rotation sensor. In this exemplary case, the first data is the peak value of the angular velocity ω in the first measurement. max1 and the second data is a peak value ω of the angular velocity in a second measurement taken after the first measurement. max2 The processing system 101 may calculate the peak value ω max2 is the peak value ω max1 is exceeded by a predetermined margin, the index data representing the worsening of the cardiac dysfunction is set.

[0025] In the detection system according to the example and non-limiting embodiment, the sensor 102 is a rotational sensor configured to measure the angular acceleration α of the rotational sensor, and the processing system 101 is configured to calculate the time integral of the angular acceleration α and estimate the angular velocity ω as a function of time t.

number

[0026] In the detection system according to the exemplary and non-limiting embodiment, the sensor 102 is a three-axis gyroscope and the processing system 101 is configured to calculate the total angular velocity of the three-axis gyroscope according to the following equation:

number

[0027] In a detection system according to an exemplary and non-limiting embodiment, the processing system calculates the angular displacement θ of the three-axis gyroscope according to the following equation: xyz (t).

number

[0028] In the detector system according to an exemplary and non-limiting embodiment, the processing system 101 is configured to receive electrical signals from the electrodes 109 and 110 on the skin of the individual 111, and the processing system 101 is configured to generate an electrocardiogram "ECG" for the time interval of each measurement performed by the sensor 102. The ECG signal can be utilized to improve the determination of worsening periods of cardiac decline.

[0029] The processing system 101 may be implemented with, for example, one or more processor circuits, each of which may be a programmable processor circuit with appropriate software, a dedicated hardware processor such as, for example, an application specific integrated circuit "ASIC," or a configurable hardware processor such as, for example, a field programmable gate array "FPGA." It is also possible for the device 107 to configure a memory system such that the device 107 can operate autonomously without being connected to the data network 108. The memory system of the device 107 may comprise, for example, one or more memory circuits, such as random access memory "RAM" circuits.

[0030] FIG. 2a illustrates a detector system according to an exemplary and non-limiting embodiment for non-invasively detecting worsening cardiac dysfunction. Moreover, FIG. 2a illustrates a schematic view of the right side of the heart. The detector system comprises a sensor 202, e.g., a gyroscope, configured to generate a measurement signal when the sensor 202 is in a motion-sensing relationship with the jugular vein 205 of the individual. In FIG. 2, a direction perpendicular to the skin 204 is substantially parallel to the z-axis of the coordinate system 299. The detector system comprises a processing system 201 configured to receive the measurement signal from the sensor 202. The detector system comprises a memory system 203 communicatively connected to the processing system 201. In this exemplary case, the processing system 201 and the memory system 203 are implemented as cloud services in an external data network 208.

[0031] The exemplary detector system shown in Fig. 2 comprises a sheet 212 of flexible material provided with an adhesive for attaching the sensor 202 to the skin 204 of an individual. The sensor 202 can therefore be used in different postures of the individual, such as when the individual is standing. The sensor 202 is configured to maintain a wireless link for transferring the measurement signal from the sensor 202 to a gateway, router or other suitable element of the data network 208. The wireless link can be, for example, a wireless link such as a Bluetooth link or a Near Field Communication "NFC" link. It is also possible that the wireless link is an optical link or an infrared link.

[0032] FIG. 2a shows a schematic of the right side of the heart during systole. As right ventricular pressure rises due to worsening cardiac hypofunction, leakage from the tricuspid valve increases during systole. This leakage causes turbulent regurgitation into the right atrium. This turbulent regurgitation causes high frequency oscillations in the jugular venous pressure "JVP" waveform. Plot 212 in FIG. 2b shows the spectrum of gyroscopic rotational energy in a case of cardiac hypofunction, and plot 213 shows the spectrum of gyroscopic rotational energy in a normal case. Thus, worsening cardiac hypofunction can be detected based on changes in the high frequency oscillations of the jugular venous pressure "JVP."

[0033] In the detector system shown in Fig. 2a, the processing system 201 is configured to calculate the frequency spectrum of the measurement signal and to calculate the energy of a part of the frequency spectrum above a predetermined frequency limit, which may be, for example, 20 Hz. In this exemplary case, the first data may be a calculated energy corresponding to a first measurement and the second data may be a calculated energy corresponding to a second measurement taken after the first measurement. The processing system 201 is configured to set the index data to be indicative of a worsening cardiac decline depending on the situation where a comparison between the first data and the second data represents an increase in the calculated energy.

[0034] FIG. 3 shows an example waveform 314 of a jugular venous pressure "JVP" and an example waveform 315 of an electrocardiogram "ECG". The waveform 314 also shows the jugular venous pressure during the expiratory phase ("ex") and during the inhalation phase ("inhalation"). During the inhalation phase, the intrathoracic pressure in the chest cavity decreases, allowing more blood to enter the right atrium of the heart. As a result, the jugular vein partially empties. As a result, the pulmonary artery pulsation is more easily transmitted to the rotation sensor and / or another motion sensor. In particular, the c-wave of the jugular venous pulse is altered by the sudden increase in pulmonary artery pressure during systole. In hypofunction, where the right atrial pressure is high, the decrease in intrathoracic pressure does not empty the jugular vein as it would normally. Thus, in hypofunction, the respiratory cycle does not modulate the output signal of the rotation sensor and / or another motion sensor as it would normally. Thus, worsening hypofunction can be detected based on the change in the modulation by the respiratory cycle.

[0035] In the detector system according to an exemplary and non-limiting embodiment, the processing system is configured to receive a signal indicative of the inhalation and exhalation phases of the individual's breath and to detect a modulation of the measurement signal due to the alternating inhalation and exhalation phases. In this exemplary case, the first data may be a modulation detected during a first measurement and the second data may be a modulation detected during a second measurement performed after the first measurement. The modulation may be represented, for example, as a difference in amplitude, power, etc. of the measurement signal between the exhalation and inhalation phases. The processing system is configured to set the indicator data to represent a worsening period of cardiac decline depending on a situation in which a comparison between the first data and the second data represents a weakening of the modulation.

[0036] In the detector system according to the exemplary and non-limiting embodiments, sensor fusion is used, i.e. different sensors are used to generate a measurement signal that depends on the jugular vein pressure, for example an acceleration sensor is used in conjunction with a gyroscope, and drifts in the signal level typical of a particular gyroscope can be corrected with the aid of the acceleration sensor and, for example, a Kalman filter.

[0037] 4 shows a flow chart of a method for non-invasively detecting worsening cardiac decline according to an exemplary and non-limiting embodiment, the method comprising the following acts: Action 401: generating a first portion of a measurement signal with a sensor in motion sensitive relationship with a jugular vein of an individual and storing first data based on the first portion of the measurement signal in a memory system; Action 402: generating a second portion of a measurement signal with a sensor in motion sensitive relationship with a jugular vein of the individual; Operation 403: Comparing first data stored in the memory system, the first data being based on an earlier generated first portion of the measurement signal, and second data being based on a later generated second portion of the measurement signal; Action 404: Forming indicator data indicative of worsening cardiac decline based on a comparison of the first data and the second data. Includes.

[0038] In a method according to an exemplary and non-limiting embodiment, the sensor is a rotational sensor that, when applied to the individual's skin and in motion-sensing relationship with the individual's jugular vein, generates a measurement signal indicative of rotation of the rotational sensor.

[0039] In a method according to an exemplary and non-limiting embodiment, the sensor is a rotational sensor measuring an angular velocity of the rotational sensor, and the method includes setting the index data to represent a worsening cardiac decline in response to a comparison between the first data and the second data representing an increase in a peak value of the angular velocity.

[0040] In a method according to an exemplary and non-limiting embodiment, the sensor is a rotational sensor measuring angular acceleration of the rotational sensor, and the method includes calculating a time integral of the measured angular acceleration, and setting the index data to represent a worsening cardiac decline in response to a situation in which a comparison between the first data and the second data represents an increase in a peak value of the calculated time integral.

[0041] In a method according to an exemplary and non-limiting embodiment, the sensor comprises a gyroscope, and one or more output signals of the gyroscope represent the measurement signals. In a method according to an exemplary and non-limiting embodiment, the gyroscope is a three-axis gyroscope, and the method includes calculating a total angular velocity of the three-axis gyroscope according to the following formula:

number

[0042] A method according to an exemplary and non-limiting embodiment includes calculating the angular displacement of a three-axis gyroscope according to the following equation:

number

[0043] A method according to an exemplary and non-limiting embodiment includes calculating a frequency spectrum of the measurement signal, calculating the energy of a portion of the frequency spectrum that exceeds a predetermined frequency limit, and setting index data to represent a worsening cardiac decline in response to a situation in which a comparison between the first data and the second data represents an increase in the energy of said portion of the frequency spectrum.

[0044] A method according to an exemplary and non-limiting embodiment includes receiving a signal indicative of inhalation and exhalation phases of an individual's breathing, detecting a modulation of the measurement signal due to the alternating inhalation and exhalation phases, and setting index data to represent worsening cardiac decline in response to a comparison between the first data and the second data representing a weakening of the modulation.

[0045] A method according to an example and non-limiting embodiment includes receiving one or more electrical signals from electrodes on the individual's skin and creating an electrocardiogram "ECG" for a time interval corresponding to the first and second data.

[0046] In a method according to an exemplary and non-limiting embodiment, the sensor maintains a wireless link for transferring measurement signals from the sensor to a processing system configured to form index data.

[0047] In a method according to an exemplary and non-limiting embodiment, the sensor is part of a mobile phone.

[0048] A computer program according to the exemplary and non-limiting embodiments comprises computer executable instructions for controlling a programmable data processing system to perform operations associated with the methods according to any of the exemplary and non-limiting embodiments described above.

[0049] A computer program according to an exemplary and non-limiting embodiment includes a software module for controlling a programmable data processing system to detect worsening of declining cardiac function, the software module including computer executable instructions for controlling the programmable data processing system to receive a measurement signal from a sensor adapted to generate a measurement signal when in motion sensing relationship with an individual's jugular vein, store first data based on a first portion of the measurement signal in a memory system, compare the first data to second data based on a later generated second portion of the measurement signal, and form indicator data indicative of worsening of declining cardiac function based on the comparison of the first data and the second data.

[0050] A software module may be, for example, a subroutine or function implemented by a programming tool suitable for a programmable data processing system.

[0051] A computer program product according to the exemplary and non-limiting embodiments includes a computer readable medium, such as a compact disc "CD", encoded with a computer program according to the exemplary embodiments of the present invention.

[0052] A signal according to the exemplary and non-limiting embodiments is encoded to carry information that defines a computer program according to the exemplary embodiments of the present invention.

[0053] The specific examples provided in the above description should not be construed as limiting the scope and / or applicability of the appended claims. The lists and groups of examples provided in the above description are not exhaustive, unless expressly stated otherwise. Correspondingly, the example waveforms and other example results shown above and / or in the figures should not be construed as limiting the scope and / or applicability of the appended claims.

Claims

1. 1. A detector system for detecting worsening cardiac decline, the detector system comprising: a processing system (101, 201) configured to receive a measurement signal; a sensor (102, 202) configured to generate a measurement signal when in motion sensitive relationship with a jugular vein of an individual; A detector system comprising: a memory system (103, 203) communicatively connected to a processing system, The processing system includes: comparing first data stored in the memory system, the first data being based on an earlier generated first portion of the measurement signal, with second data being based on a later generated second portion of the measurement signal; 20. The detector system of claim 19, further comprising: a detector unit configured to generate indicator data indicative of a worsening of the cardiac decline based on the comparison of the first data and the second data.

2. 2. The detector system of claim 1, wherein the sensor (102, 202) is a rotational sensor configured to generate the measurement signal indicative of rotation of the rotational sensor when applied to the skin of the individual and in a motion-sensing relationship with a jugular vein of the individual.

3. 3. The detector system of claim 2, wherein the rotation sensor is configured to measure an angular velocity of the rotation sensor, and the processing system is configured to set the index data to represent a worsening of the cardiac decline in response to a situation in which the comparison between the first data and the second data represents an increase in a peak value of the angular velocity.

4. 3. The detector system of claim 2, wherein the rotation sensor is configured to measure an angular acceleration of the rotation sensor, the processing system is configured to calculate a time integral of the angular acceleration, and the processing system is configured to set the index data to represent a worsening of the cardiac decline in response to a situation in which the comparison between the first data and the second data represents an increase in a peak value of the time integral.

5. The detector system of claim 2 , wherein the rotation sensor comprises a gyroscope, one or more output signals of the gyroscope representing the measurement signal.

6. The gyroscope is a three-axis gyroscope, and the processing system is [0010] where ω is a time series of ω 1 , ω 2 , and ω 3 are connected to a triaxial gyroscope. ｘｙｚ (t) is the total angular velocity as a function of time t, and ω ｘ , ω ｙ , ω ｚ 6. The detector system of claim 5, wherein: σ is an angular velocity measured by the three-axis gyroscope about mutually orthogonal geometric axes, and the processing system is configured to set the index data to represent a worsening of the cardiac decline in response to a situation in which the comparison between the first data and the second data represents an increase in a peak value of the total angular velocity.

7. The processing system comprises: [0025] where θ ｘｙｚ (t) is the angular displacement as a function of time t, t0 being the beginning of a measurement period, and the processing system is configured to determine whether the comparison of the first data and the second data is a peak-to-peak value of the angular displacement (θ ｘｙｚ (t) ｍａｘ -θ ｘｙｚ (t) ｍｉｎ The detector system according to claim 6, configured to set the index data to represent a worsening of the cardiac decline in response to a condition representing an increase in the cardiac function.

8. 3. The detector system according to claim 1, wherein the processing system is configured to calculate a frequency spectrum of the measurement signal, calculate an energy in a portion of the frequency spectrum above a predetermined frequency limit, and set the index data to represent a worsening of the cardiac decline depending on a situation in which the comparison between the first data and the second data represents an increase in energy in the portion of the frequency spectrum.

9. 3. The detector system of claim 1, wherein the processing system is configured to receive a signal indicative of inhalation and exhalation phases of breathing of the individual, detect a modulation of the measurement signal due to alternating inhalation and exhalation phases, and set the indicator data to be indicative of a worsening of the cardiac decline in response to a situation in which the comparison between the first data and the second data represents a weakening of the modulation.

10. 10. The detector system of claim 1, wherein the processing system is configured to receive one or more electrical signals from electrodes on the skin of the individual, the processing system being configured to generate an electrocardiogram for a time interval corresponding to the first and second portions of the measurement signals.

11. The detector system of any one of claims 1 to 10, wherein the processing system and the sensor are configured to maintain a wireless link for transferring the measurement signals from the sensor to the processing system.

12. The detector system of any one of claims 1 to 10, wherein the sensor (102) is part of a mobile phone.

13. 1. A method for detecting worsening cardiac hypofunction, comprising generating (401, 402) a measurement signal with a sensor in motion sensitive relationship with an individual's jugular vein, the method comprising: The method comprises: comparing (403) first data stored in a memory system, the first data being based on an earlier generated first portion of the measurement signal, and second data being based on a later generated second portion of the measurement signal; and forming (404) indicator data indicative of worsening cardiac decline based on the comparison of the first data and the second data.

14. 1. A computer program for controlling a programmable data processing system to detect worsening cardiac decline, the computer program comprising: receiving a measurement signal from a sensor adapted to generate a measurement signal when in motion sensing relationship with a jugular vein of the individual; A computer program comprising computer executable instructions for controlling: The computer program is configured to cause the programmable data processing system to: storing, in a memory system, first data based on a previously generated first portion of the measurement signal; comparing the first data with second data based on a subsequently generated second portion of the measurement signal; The computer program product further comprises computer executable instructions for controlling the computer to generate index data indicative of worsening of the cardiac decline based on the comparison between the first data and the second data.

15. 15. A computer program product comprising a non-transitory computer readable medium encoding the computer program of claim 14.

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