A detector system and a method for detecting exacerbation of heart hypofunction

Abstract

A detector system for non-invasive detection of deterioration of cardiac function includes a sensor (102), such as a gyroscope, configured to generate a measurement signal when in motion sensing relation to an individual's jugular vein (105). The detector system includes a processing system (101) configured to receive the measurement signal and a memory system (103) communicatively connected to the processing system. Since changes in jugular vein pressure behavior can indicate the development of cardiac function decline, the processing system is configured to compare first data stored in the memory system based on an earlier-generated measurement signal with second data based on a later-generated measurement signal, and to form indicator data indicating deterioration of cardiac function based on the comparison between the first and second data.

Description

Technical Field

[0001] The present disclosure relates to a detector system and method for detecting worsening cardiac function impairment. Furthermore, the present disclosure relates to a computer program for detecting worsening cardiac function impairment. Prior Art

[0002] Abnormalities that may develop in the cardiovascular system can gradually deteriorate an individual's health if not diagnosed and properly addressed and / or treated. For example, pulmonary hypertension (PAH) often represents an early sign of a future worsening of cardiac function, which occurs an average of three to four weeks after the onset of PAH. In many cases, PAH can predict worsening cardiac function at such an early stage that traditional signs of cardiac function, such as weight gain and elevated blood pressure, are typically not present. Cardiac function diagnosed at an early stage can often be addressed and / or treated, and mortality and the need for hospitalization can be significantly reduced.

[0003] Abbott Laboratories of Chicago, USA, has developed a system for detecting worsening heart function impairment. The system includes a micromechanical sensor and a receiver that receives measurement data from the micromechanical sensor. The micromechanical sensor is placed in the pulmonary artery via the right side of the heart. Therefore, Abbott's method for detecting worsening heart function impairment is an invasive method. The receiver of Abbott's system can be placed, for example, on the patient's bed. While the patient is lying in bed, the micromechanical sensor transmits measurement data via the receiver to a cloud service. The measurement data can indicate pulmonary hypertension (PAH), which in many cases represents an early sign of future worsening heart function impairment.

[0004] The aforementioned invasive methods carry inherent risks associated with the need for invasive surgery on the human body. Furthermore, some invasive methods may only be used during surgical procedures. On the other hand, non-invasive methods based on Doppler ultrasound measurement require expensive equipment and skilled and experienced examiners. Therefore, there is a need for non-invasive systems and methods for detecting worsening cardiac function. Summary of the Invention

[0005] The following is a simplified overview to provide a basic understanding of some aspects of various embodiments of the present invention. This overview is not an extensive overview of the present invention. It is not intended to identify key or critical elements of the present invention, nor is it intended to delineate the scope of the present invention. The following overview merely presents some concepts of the present invention in a simplified form as a prelude to a more detailed description of exemplary embodiments of the present invention.

[0006] In this document, the prefix "geometry" is used to refer to geometric concepts that need not be part of any real object. Geometric concepts can be, for example, geometric points, straight or curved geometric lines, geometric planes, non-planar geometric surfaces, geometric spaces, 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 function impairment is proposed. The detector system according to the present invention comprises: – a processing system configured to receive the measurement signal; - a sensor, such as a gyroscope, configured to generate a measurement signal when in motion sensing relationship with a jugular vein (lat. vena jugularis) of the individual; and – A memory system that is communicatively connected to the processing system.

[0008] The processing system is configured to: - compares 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 indicating worsening of cardiac hypofunction based on a comparison between the first data and the second data.

[0009] The jugular vein is directly connected to the right atrium of the heart, and therefore, changes in jugular venous pressure are caused by changes in blood flow and blood pressure due to the filling and contraction of the right atrium and right ventricle. Based on changes in the behavior of jugular venous pressure, non-invasive examination of the right side of the heart (i.e., the right ventricle and right atrium) is possible. In the system according to the present invention, possible changes in the behavior of jugular venous pressure are detected by comparing first data based on an earlier generated portion of the measurement signal stored in a memory system with second data based on a later generated portion of the measurement signal. In addition to the aforementioned first and second portions of the measurement signal, third, fourth, and so on portions of the measurement signal can be generated, thereby monitoring the development of a hypotensive condition over time.

[0010] The sensor is advantageously a rotation sensor that is reliably attached to the individual's skin and in motion-sensing relationship with the individual's jugular vein. The rotation sensor is advantageously positioned so that one end of the rotation sensor is closer to the jugular vein than the other end. Therefore, changes in jugular vein pressure cause greater movement at the front end of the rotation sensor than at the rear end, and this difference manifests as rotational movement of the rotation sensor. Movements that are independent of jugular vein pressure and have substantially the same amplitude and direction across the entire skin area covered by the rotation sensor do not cause significant rotational movement of the rotation sensor, but only translational movement. Consequently, this movement does not contribute to a significant signal component in the rotation sensor's output signal. Consequently, rotation sensors that measure rotation are less sensitive to movements unrelated to changes in jugular vein pressure than, for example, acceleration sensors that measure translational movement.

[0011] According to the present invention, a novel method for non-invasively detecting worsening cardiac function impairment is also proposed. The method according to the present invention comprises: – generating a measurement signal using a sensor in motion-sensing relation to the jugular vein of the individual; - 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 indicating worsening of cardiac hypofunction based on a comparison between the first data and the second data.

[0012] According to the present invention, a novel computer program for controlling a programmable data processing system to detect worsening cardiac function impairment is also provided. The computer program includes computer executable instructions for controlling the programmable data processing system to: – receiving a measurement signal from a sensor adapted to generate the measurement signal when in motion sensing relationship with a jugular vein of the individual; - storing the first data of the earlier generated first portion based on the measurement signal in a memory system; - comparing the first data with second data based on a second portion of the measurement signal generated later; and - forming indicator data indicating worsening of cardiac hypofunction based on a comparison between the first data and the second data.

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

[0014] Exemplary, non-limiting embodiments are described in the accompanying claims.

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

[0016] The verbs "to comprise" and "to include" are used in this document as open limitations that neither exclude nor require the existence of also unrecited features.

[0017] Unless expressly stated otherwise, the features recited in the appended claims are mutually freely combinable.

[0018] Furthermore, it is to be understood that the use of "a" or "an" (i.e. the singular) in this document does not exclude a plural. Simple diagram description

[0019] Exemplary, non-limiting embodiments and their advantages are explained in more detail below with reference to the accompanying drawings.

[0020] [ FIG. 1 ] illustrates a detector system for non-invasively detecting worsening cardiac function impairment according to an exemplary but non-limiting embodiment.

[0021] [FIG. 2a] and [FIG. 2b] illustrate the functionality of a detector system for non-invasively detecting worsening cardiac function impairment according to an exemplary but non-limiting embodiment.

[0022] [ FIG. 3 ] shows exemplary waveforms of jugular venous pressure “JVP” and electrocardiogram “ECG” to illustrate the functionality of a detector system for non-invasively detecting worsening cardiac function impairment according to an exemplary but non-limiting embodiment.

[0023] [ FIG. 4 ] A flow chart showing a method for non-invasively detecting worsening cardiac function impairment according to an exemplary but non-limiting embodiment. Implementation Method

[0024] The specific examples set forth in the following description should not be construed as limiting the scope and / or applicability of the appended claims. Unless expressly stated otherwise, the lists and groups of examples set forth in the description are not exhaustive.

[0025] FIG1 illustrates a detector system for non-invasively detecting worsening cardiac function impairment according to an exemplary, non-limiting embodiment. The detector system includes a sensor 102 configured to generate a measurement signal when the sensor 102 and a jugular vein 105 of an individual 111 are in a motion-sensing relationship. In the exemplary detector system shown in FIG1 , the sensor 102 is a rotation sensor, such as a gyroscope, configured to generate a measurement signal indicative of the rotation of the rotation sensor when the rotation sensor is positioned against the skin 104 of the individual 111 so that the rotation sensor and the jugular vein 105 are in a motion-sensing relationship. However, it is also possible that the sensor is an optical sensor, for example, adapted to optically measure the movement induced by the jugular vein 105 on the skin 104. In portion 106 of FIG1 , the direction perpendicular to the skin 104 is substantially parallel to the z-axis of the coordinate system 199. In this exemplary embodiment, the sensor 102 is part of a device 107 positioned against the skin 104 of the individual 111. Device 107 can be, for example, a mobile phone. The detector system includes a processing system 101 configured to receive measurement signals from sensor 102. Furthermore, the detector system includes a memory system 103 communicatively connected to processing system 101. In this exemplary embodiment, memory system 103 is implemented as a cloud service on an external data network 108.

[0026] The jugular vein 105 is directly connected to the right atrium of the heart. Therefore, changes in jugular vein pressure (JVP) are caused by changes in blood flow and blood pressure due to the filling and contraction of the right atrium and right ventricle. Based on changes in jugular vein pressure behavior, non-invasive testing of the right side of the heart (i.e., the right ventricle and right atrium) is possible. To detect possible changes in jugular vein pressure behavior, the processing system 101 is configured to compare first data stored in the memory system 103 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. Furthermore, the processing system 101 is configured to generate indicator data indicating worsening cardiac function based on the comparison between the first and second data. The device 107 may include, for example, a display for presenting the indicator data to a user. The display is not shown in FIG. 1 . Alternatively, the device may be configured to transmit the indicator data to a data network 108. The first and second data can be defined in different ways based on the first and second parts of the measurement signal. Some examples are presented below, but it is worth noting that the present invention is not limited to the examples presented below.

[0027] In a detection system according to an exemplary, non-limiting embodiment, sensor 102 is a rotation sensor configured to measure the angular velocity ω of the rotation sensor. In this exemplary embodiment, the first data may be a peak value ω max1 of the angular velocity during a first measurement, and the second data may be a peak value ω max2 of the angular velocity during a second measurement made after the first measurement. Processing system 101 is configured to set indicator data indicating worsening cardiac hypofunction in response to the peak value ω max2 exceeding the peak value ω max1 by a predetermined margin.

[0028] In a detection system according to an exemplary but non-limiting embodiment, the sensor 102 is a rotation sensor configured to measure the angular acceleration α of the rotation sensor, and the processing system 101 is configured to calculate the time integral of the angular acceleration α to estimate the angular velocity ω as a function of time t: (1) Where t0 is the starting point of the measurement cycle under consideration. In this exemplary case, the first data may be the peak value ω max1 of the angular velocity in the first measurement, and the second data may be the peak value ω max2 of the angular velocity in the second measurement made after the first measurement. Processing system 101 is configured to set indicator data indicating worsening cardiac hypofunction in response to the peak value ω max2 exceeding the peak value ω max1 by a predetermined margin.

[0029] In the detection system according to an exemplary but 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 formula: , (2) in is the total angular velocity as a function of time t, is the angular velocity measured by a three-axis gyroscope about a geometric axis parallel to the x-axis of coordinate system 199, is the angular velocity measured by a three-axis gyroscope about a geometric axis parallel to the y-axis of coordinate system 199, and The angular velocity is measured by a three-axis gyroscope about a geometric axis parallel to the z-axis of coordinate system 199. In this exemplary embodiment, the first data may be the peak value ω xyzmax1 of the calculated total angular velocity during a first measurement, and the second data may be the peak value ω xyzmax2 of the calculated total angular velocity during a second measurement made after the first measurement. Processing system 101 is configured to set indicator data indicating worsening cardiac hypofunction in response to the peak value ω xyzmax2 exceeding the peak value ω xyzmax1 by a predetermined margin.

[0030] In a detection system according to an exemplary but non-limiting embodiment, the processing system is configured to calculate the angular displacement of the three-axis gyroscope according to the following formula: : (3) Where t0 is the starting point of the measurement period under consideration. In this exemplary case, the first data may be the peak-to-peak value of the angular displacement in the first measurement ( - ), and the second data may be a corresponding peak-to-peak value of a second measurement made after the first measurement. Processing system 101 is configured to set indicator data indicating worsening cardiac hypofunction in response to the peak-to-peak value of the second measurement exceeding the peak-to-peak value of the first measurement by a predetermined margin.

[0031] In a detector system according to an exemplary, non-limiting embodiment, processing system 101 is configured to receive electrical signals from electrodes 109 and 110 on the skin of individual 111 and to generate an electrocardiogram (ECG) for each time interval of each measurement performed by sensor 102. The ECG signal can be utilized to improve the determination of the worsening stage of cardiac insufficiency.

[0032] Processing system 101 may be implemented, for example, using one or more processor circuits, each of which may be a programmable processor circuit provided with appropriate software, a dedicated hardware processor such as an application-specific integrated circuit (ASIC), or a configurable hardware processor such as a field programmable gate array (FPGA). It is also possible that device 107 includes a memory system, allowing device 107 to operate independently without being connected to data network 108. The memory system of device 107 may include, for example, one or more memory circuits, each of which may be, for example, a random access memory (RAM) circuit.

[0033] FIG. 2 a illustrates a detector system for non-invasively detecting worsening cardiac insufficiency according to an exemplary but non-limiting embodiment.

[0034] Furthermore, Figure 2a schematically illustrates the right side of the heart. The detector system includes a sensor 202, such as a gyroscope, configured to generate a measurement signal when the sensor 202 and the individual's jugular vein 205 are in motion sensing relationship. In Figure 2 , the direction perpendicular to the skin 204 is substantially parallel to the z-axis of the coordinate system 299. The detector system includes a processing system 201 configured to receive the measurement signal from the sensor 202. The detector system includes a memory system 203 communicatively connected to the processing system 201. In this exemplary embodiment, the processing system 201 and the memory system 203 are implemented as cloud services on an external data network 208.

[0035] The exemplary detector system shown in FIG2 includes a sheet of flexible material 212 that provides an adhesive for attaching sensor 202 to an individual's skin 204. Thus, sensor 202 can be used in various positions on an individual, for example, while the individual is standing. Sensor 202 is configured to maintain a wireless connection to transfer measurement signals from sensor 202 to a gateway, router, or some other suitable component of data network 208. The wireless connection can be, for example, a radio link, such as a Bluetooth® link or a Near Field Communication (NFC) link. It is also possible for the wireless link to be an optical link or an infrared link.

[0036] Figure 2a schematically illustrates the right side of the heart during systole. When right ventricular pressure increases due to worsening heart failure, leakage through the tricuspid valve increases during systole. This leakage causes turbulent backflow into the right atrium. This turbulent backflow causes high-frequency oscillations in the waveform of the jugular venous pressure (JVP). Plot 212 in Figure 2b shows the spectrum of the gyroscopic rotational energy in a hypotensive state, while plot 213 shows the spectrum of the gyroscopic rotational energy in a normal state. Therefore, worsening heart failure can be detected based on changes in the high-frequency oscillations of the jugular venous pressure (JVP).

[0037] In the detector system shown in FIG2a , processing system 201 is configured to calculate the spectrum of the measurement signal and calculate the energy of the portion of the spectrum above a predetermined frequency limit, which may be, for example, 20 Hz. In this exemplary embodiment, the first data may be the calculated energy corresponding to the first measurement, and the second data may be the calculated energy corresponding to a second measurement made after the first measurement. Processing system 201 is configured to set indicator data indicating worsening cardiac hypofunction in response to a comparison between the first data and the second data indicating an increase in the calculated energy.

[0038] Figure 3 shows an exemplary waveform 314 of jugular venous pressure (JVP) and an exemplary waveform 315 of an electrocardiogram (ECG). Waveform 314 shows jugular venous pressure during the exhalation phase ("Exhale") and the inspiration phase ("Inspire"). During the inspiration phase, intrathoracic pressure in the chest cavity decreases, allowing more blood to enter the right atrium of the heart. As a corollary, the jugular vein partially empties. This, in turn, allows for better conduction of the pulmonary artery pulse to the rotation sensor and / or another motion sensor. In particular, the C-wave of the jugular venous pulse is modified by the rapid increase in pulmonary artery pressure during the systolic phase. In hypocardia, when right atrial pressure is higher, the decrease in intrathoracic pressure does not empty the jugular vein to the same extent as in normal conditions. Therefore, in hypocardia, the respiratory cycle does not modulate the output signal of the rotation sensor and / or another motion sensor as in normal conditions. Therefore, worsening hypocardia can be detected based on changes in modulation caused by the respiratory cycle.

[0039] In a detector system according to an exemplary, non-limiting embodiment, a processing system is configured to receive signals indicative of the inhalation and exhalation phases of an individual's breathing and detect modulation of a measurement signal caused by alternating inhalation and exhalation phases. In this exemplary embodiment, the first data may be the modulation detected during a first measurement, and the second data may be the modulation detected during a second measurement taken after the first measurement. The modulation may be represented, for example, by a difference in amplitude, power, etc., of the measurement signal during the inhalation and exhalation phases. The processing system is configured to set indicator data to indicate a worsening stage of hypocardia in response to a comparison between the first and second data indicating a decrease in the modulation.

[0040] In a detector system according to an exemplary, non-limiting embodiment, sensor fusion is utilized, i.e., different sensors are used to generate a measurement signal that is dependent on jugular vein pressure. For example, an accelerometer can be used together with a gyroscope, so that the drift in the signal level typical of certain gyroscopes is corrected using the accelerometer and, for example, a Kalman filter.

[0041] FIG4 shows a flow chart of a method for non-invasively detecting worsening of cardiac insufficiency according to an exemplary but non-limiting embodiment. The method comprises the following steps: Action 401: generating a first portion of a measurement signal using a sensor in motion sensing relationship with a jugular vein of the individual, and storing first data based on the first portion of the measurement signal in a memory system; - Action 402: Using the sensor in relation to the jugular vein of the individual for movement sensing to generate a second portion of the measurement signal; Action 403: comparing first data stored in the 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 Action 404: Generating indicator data indicating worsening of cardiac hypofunction based on the comparison between the first data and the second data.

[0042] In a method according to an exemplary, non-limiting embodiment, the sensor is a rotation sensor that generates a measurement signal indicative of rotation of the rotation sensor when placed against the skin of an individual and in motion sensing relationship with the individual's jugular vein.

[0043] In a method according to an exemplary, non-limiting embodiment, the sensor is a rotation sensor that measures the angular velocity of the rotation sensor, and the method includes setting indicator data to indicate worsening of hypocardia in response to a situation in which a comparison between first data and second data indicates an increase in a peak value of the angular velocity.

[0044] In a method according to an exemplary, non-limiting embodiment, the sensor is a rotation sensor that measures angular acceleration of the rotation sensor, and the method includes calculating a time integral of the measured angular acceleration and setting indicator data to indicate worsening of hypocardia in response to a situation in which a comparison between first data and second data indicates an increase in a peak value of the calculated time integral.

[0045] In a method according to an exemplary, non-limiting embodiment, the sensor includes a gyroscope, such that one or more outputs of the gyroscope represent a measurement signal. In a method according to an exemplary, non-limiting embodiment, the gyroscope is a three-axis gyroscope, and the method includes calculating the total angular velocity of the three-axis gyroscope according to the following formula: , (4) in is the total angular velocity as a function of time t, is the angular velocity measured by the three-axis gyroscope in the x direction, is the angular velocity measured by the three-axis gyroscope in the y direction, and The indicator data is set to indicate worsening of hypocardia in response to a situation in which a comparison between the first data and the second data indicates an increase in the peak value of the calculated total angular velocity.

[0046] The method according to an exemplary and non-limiting embodiment comprises calculating the angular displacement of the three-axis gyroscope according to the following formula: (5) in is the angular displacement as a function of time t and t0 is the starting point of the measurement period under consideration, and the method comprises responding to wherein a comparison between the first data and the second data represents a peak-to-peak value of the angular displacement ( - ) increases and sets indicator data to indicate worsening of cardiac function decline.

[0047] The method according to an exemplary, non-limiting embodiment comprises calculating a frequency spectrum of a measurement signal, calculating the energy of a portion of the frequency spectrum above a predetermined frequency limit, and setting indicator data to indicate worsening of hypocardia in response to a situation in which a comparison between first data and second data indicates an increase in the energy of the portion of the frequency spectrum.

[0048] A method according to an exemplary, non-limiting embodiment includes receiving signals indicative of inhalation and exhalation phases of an individual's breathing, detecting modulation of a measurement signal caused by alternating inhalation and exhalation phases, and setting indicator data to indicate worsening hypocardia in response to a situation in which a comparison between first data and second data indicates a reduction in the modulation.

[0049] A method according to an exemplary, non-limiting embodiment includes receiving one or more electrical signals from electrodes on the skin of an individual and generating an electrocardiogram (ECG) for time intervals corresponding to first and second data.

[0050] In a method according to an exemplary and non-limiting embodiment, a sensor maintains a wireless link to transfer measurement signals from the sensor to a processing system configured to form indicator data.

[0051] In a method according to an exemplary and non-limiting embodiment, the sensor is part of a mobile phone.

[0052] The computer program according to the exemplary and non-limiting embodiments includes computer-executable instructions for controlling a programmable data processing system to perform actions related to the method according to any one of the above-described exemplary and non-limiting embodiments.

[0053] According to an exemplary, non-limiting embodiment, a computer program comprises a software module for controlling a programmable data processing system to detect worsening cardiac function impairment. The software module comprises computer executable instructions for controlling the programmable data processing system to: – receiving a measurement signal from a sensor adapted to generate the measurement signal when in motion sensing relationship with a jugular vein of the individual; - storing first data based on the first portion of the measurement signal in a memory system; - comparing the first data with second data based on a second portion of the measurement signal generated later; and - forming indicator data indicating worsening of cardiac hypofunction based on a comparison between the first data and the second data.

[0054] A software module may be, for example, a subroutine or function implemented by a programming tool suitable for a programmable data processing system.

[0055] According to an exemplary and non-limiting embodiment, a computer program product includes a computer-readable medium, such as a compact disc (CD), encoded with a computer program according to an exemplary embodiment of the invention.

[0056] The signal according to the exemplary and non-limiting embodiment is encoded to carry information defining a computer program according to the exemplary embodiment of the invention.

[0057] The specific examples presented in the foregoing description should not be construed as limiting the scope and / or applicability of the appended claims. Unless expressly stated otherwise, the lists and groups of examples presented in the foregoing description are not exhaustive. Therefore, the exemplary waveforms and other exemplary results presented above and / or in the figures should not be construed as limiting the scope and / or applicability of the appended claims.

[0058] 101: Processing System 102: Sensor 103:Memory System 104: Skin 105: Jugular vein 106: Part 107: Device 108: External Data Network 109, 110: Electrodes 111: Individual 199: Coordinate System 201:Processing System 202:Sensor 203:Memory System 204: Skin 205: Jugular vein 208: External Data Network 212: Flexible material 213: Drawing 299: Coordinate System 314: Demonstration waveform of jugular venous pressure "JVP" 315: Demonstration waveform of electrocardiogram "ECG" 401-404: Steps (actions) of the method of FIG. 4

Claims

1. A detector system for detecting deterioration of cardiac function, the detector system comprising: a processing system (101, 201) configured to receive a measurement signal; a rotation sensor (102, 202) configured to generate the measurement signal when in motion sensing relationship with an individual's jugular vein; and a memory system (103, 203) communicatively connected to the processing system, characterized in that the processing system is configured to: compare the first data stored in the memory system and based on an earlier generated first portion of the measurement signal with the second data based on a later generated second portion of the measurement signal; and form indicator data indicating the deterioration of cardiac function based on the comparison between the first data and the second data.

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

3. The detector system of claim 2, wherein the rotation sensor is configured to measure the angular velocity of the rotation sensor, and the processing system is configured to set the indicator data to indicate the deterioration of the cardiac function in response to a situation in which the comparison between the first data and the second data indicates an increase in the peak value of the angular velocity.

4. The detector system of claim 2, wherein the rotation sensor is configured to measure the angular acceleration of the rotation sensor, the processing system is configured to calculate the time integral of the angular acceleration, and the processing system is configured to set the indicator data to indicate the deterioration of the cardiac function in response to a situation in which the comparison between the first data and the second data indicates an increase in the peak value of the time integral.

5. The detector system of claim 2, wherein the rotation sensor includes a gyroscope such that one or more outputs of the gyroscope represent the measurement signal.

6. The detector system of claim 5, wherein the gyroscope is a triaxial gyroscope, and the processing system is configured to calculate the total angular velocity of the triaxial gyroscope according to the following formula: where is the total angular velocity as a function of time t, , , and are the angular velocities measured by the triaxial gyroscope about geometric axes perpendicular to each other, and the processing system is configured to set the indicator data to indicate the deterioration of cardiac function in response to a situation where the comparison between the first data and the second data indicates an increase in the peak value of the total angular velocity.

7. The detector system of claim 6, wherein the processing system is configured to calculate the angular displacement of the triaxial gyroscope according to the following formula: where is the angular displacement as a function of time t and t0 is the starting point of the measurement cycle, and the processing system is configured to set the indicator data to indicate the deterioration of the cardiac function in response to a situation in which the comparison between the first data and the second data indicates an increase in the peak-to-peak (-) of the angular displacement.

8. The detector system of claim 1 or 2, wherein the processing system is configured to calculate the spectrum of the measurement signal, calculate the energy of the portion of the spectrum above a predetermined frequency limit, and set the indicator data to indicate the deterioration of the cardiac function in response to a comparison between the first data and the second data indicating an increase in the energy of the portion of the spectrum.

9. The detector system of claim 1 or 2, wherein the processing system is configured to receive signals indicating the inspiratory and expiratory phases of the individual's breathing, detect modulation of the measurement signal caused by alternation of the inspiratory and expiratory phases, and set indicator data to indicate the deterioration of the cardiac function in response to a comparison between the first data and the second data indicating a weakening of the modulation.

10. The detector system of claim 1 or 2, wherein the processing system is configured to receive one or more electrical signals from electrodes on the skin of the individual and the processing system is configured to generate an electrocardiogram for time intervals corresponding to a first portion and a second portion of the measured signal.

11. The detector system of claim 1 or 2, wherein the processing system and the rotation sensor are configured to maintain a wireless connection to transfer the measurement signal from the rotation sensor to the processing system.

12. The detector system as requested in item 1 or 2, wherein the rotation sensor (102) is part of a mobile phone.

13. A computer program for controlling a programmable data processing system to detect deterioration of cardiac function, the computer program comprising computer-executable instructions to control the programmable data processing system to: receive a measurement signal from a rotation sensor adapted to generate the measurement signal in a motion sensing relationship with an individual's jugular vein; characterized in that the computer program further comprises computer-executable instructions to control the programmable data processing system to: store the first data based on an earlier generated first portion of the measurement signal into a memory system; compare the first data with the second data based on a later generated second portion of the measurement signal; and form indicator data indicating the deterioration of cardiac function based on the comparison between the first data and the second data.

14. A computer program product comprising a non-transitory computer-readable medium encoded with the computer program according to claim 13.

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