Apparatus and method of acquiring vital information related to cardiovascular disorder

Abstract

An apparatus acquires vital information related to a cardiovascular disorder. The apparatus includes a radar system configured to transmit a radio wave to a subject and receive the radio wave reflected by the subject. The apparatus includes a controller. The controller configured to: (a) calculate a respiratory amplitude, based on the radio wave reflected by the subject, and (b) determine a sleep status of the subject, based on the radio wave reflected by the subject. The controller is configured to: (c) judge an occurrence of sleep apnea or hypopnea, based on the respiratory amplitude and the sleep state, (d) obtain a frequency of the occurrences of sleep apnea or hypopnea, and (e) obtain a cardiovascular disorder related index (CVDI), based on a relationship between the frequency of the occurrence of sleep apnea or hypopnea and the cardiovascular disorder.

Description

APPARATUS AND METHOD OF ACQUIRING VITAL INFORMATION RELATED TO CARDIOVASCULAR DISORDERField

[0001] The present disclosure relates to apparatuses and methods of acquiring vital information related to cardiovascular disorders.Background

[0002] Pulmonary capillary wedge pressure (PCWP), used to evaluate hemodynamics including left ventricular filling pressure, is important information to diagnose and select treatments for cardiovascular disorders including heart failure (NPL 1). However, the measurement of PCWP requires a very invasive procedure. A typical PCWP measurement procedure includes the application of local anesthesia, the insertion of an introducer sheath into a vein (usually the jugular, subclavian, or femoral vein), the insertion of a Swan-Ganz catheter through the introducer sheath, the advancement of the catheter through the right atrium and right ventricle into the pulmonary artery, the inflation of the balloon to wedge the catheter into a pulmonary artery branch, the measurement of the wedge pressure (PCWP) using a connected transducer, the deflation of the balloon and the withdrawal of the catheter. Likewise, other indices of cardiovascular disorders require invasive procedures.

[0003] Recently, several millimeter-wave radar techniques (PL 1 - 3, NPL 2, NPL 3) have been applied to the acquisition of heart rates and respiratory intervals as vital information for sleep apnea and hypopnea.

[0004] Citation List

[0005] Patent Literature PL 1: Katsuya Nakagawa, et. al., Vital information measuring device, managing device, and vital information communication system, EP1887488A1. PL 2: Milan Savic, et. al., MM-wave radar vital signs detection apparatus and method of operation, WO2015 / 174879A1. PL 3: Sakamoto Takuya, et. al., Vital information acquisition apparatus and method, WO 2023 / 089372A2.

[0006] Non-Patent Literature NPL 1: Brawner CA, Shafiq A, Aldred HA, et al., Comprehensive analysis of cardiopulmonary exercise testing and mortality in patients with systolic heart failure: the Henry Ford Hospital cardiopulmonary exercise testing (FIT-CPX) project. J Card Fail. 2015;21:710-718. NPL 2: Takuya Sakamoto, Recent progress in millimeter-wave radar signal processing, 12th Global Symposium on Millimeter Waves, 2019. NPL 3: Takato Koda, et. al., Noncontact respiratory measurement for multiple people at arbitrary locations using array radar and respiratory-space clustering, IEEE Access, 2021; 9, 106895-106906. NPL4: Peter Solin et al., Influence of Pulmonary Capillary Wedge Pressure on Central Apnea in Heart Failure, Circulation, 1999;99:1574-1579.Summary

[0007] To solve the above-mentioned problem, an object of the present disclosure is to provide apparatuses and methods to acquire vital information related to cardiovascular disorders in a non-invasive manner. PCWP and other indices of cardiovascular disorders are measured by invasive methods, which increases the burden on patients. Thus, for the early detection of the acute exacerbation of heart failure and the suppression of readmission rate of heart failure patients, a non-invasive long-term estimation modality of PCWP is strongly desired.

[0008] One general aspect includes an apparatus for acquiring vital information related to a cardiovascular disorder. In some embodiments the apparatus comprises a radar system configured to transmit a microwave to a subject and receive the microwave reflected by the subject. In some embodiments the apparatus comprises a circuitry or a controller configured to calculate a respiratory amplitude, based on the microwave reflected by the subject, determine a sleep-wake status of the subject, based on the microwave reflected by the subject, obtain an occurrence of sleep apnea or hypopnea is occurring, based on the respiratory amplitude and the sleep-wake state, and obtain a cardiovascular disorder related index, based on a relationship between the occurrence of sleep apnea or hypopnea and the cardiovascular disorder.

[0009] The terms “system”, “unit”, “part”, “member”, and “means” used herein generally refer to a single hardware and / or software component or a group of multiple single hardware and / or software components, and are interchangeably used. For example, a "unit" may include a microprocessor, a storage medium, and software code executed by the microprocessor to implement the described function.

[0010] The term “sleep-wake classification” used herein generally refers to an act or a step of classifying the sleep status of the subject to either “sleeping” or “awake”.

[0011] The term “sleep stage classification” used herein generally refers to an act or a step of classifying the sleep status of the subject to either one of “wake”, “REM”, “N1”, “N2”and “N3” according to the definition by the American Academy of Sleep Medicine (AASM) or either one of “wake”, “REM”, “S1”, “S2”, “S3”, and “S4” according to the definition by Rechtschaffen & Kales (R&K). Another classification may be used.

[0012] Respiratory Detection Unit In some embodiments, the apparatus may include a non-invasive or non-contact unit configured to detect signals related to respiratory movements of the subjects. In some embodiments, the unit for respiratory detection, or the respiratory detection unit, may be a radar unit. The details of the radar unit will be explained below.

[0013] The respiratory detection unit may be disposed inside the body of the apparatus, integrated in the apparatus, or attached or fixed to the apparatus. In some embodiments, the respiratory detection unit may be disposed as a unit separate from the apparatus and be configured to be connected to the apparatus. The connection may be wired or wireless. The respiratory detection unit may be connected to the control unit for communication. The communication may be at least data transmission from the respiratory detection unit to the apparatus.

[0014] In some embodiments, the respiratory detection unit may detect signals related to movements of the chest or thorax of the subject. In some embodiments, the respiratory detection unit may detect signals related to movements of the belly or abdomen of the subject. Any one or more of other body parts which move in relation to the respiration may be measured.

[0015] As a sign, an occurrence, or a symptom of apnea or hypopnea, the amplitude of the respiratory movement of a body part decreases from, or becomes smaller than, the amplitude of healthy respiratory movements. In some embodiments, if the amplitude is smaller than that of a healthy state, it may be determined to be a sign (also referred to as “occurrence” in the present specification) of apnea or hypopnea, or it may be determined that an occurrence of apnea or hypopnea is detected. In some embodiments, the amplitude of the healthy state may be measured for the same subject. In some embodiments, the amplitude of the healthy state may be measured for another person, or may be a statistically obtained value.

[0016] In some embodiments, if the amplitude is smaller than a predetermined value, it may be determined or judged to be a sign or an occurrence of apnea or hypopnea. The predetermined value may be 80%, 70%, 60%, 50%, 40%, 30% or the like of the amplitude of a healthy state or non-apnea state. For example, if the amplitude becomes smaller than 70 % of the non-apnea state or if the amplitude decreases by more than 30% of the non-apnea state, it may be determined or judged to be a sign or an occurrence of apnea or hypopnea.

[0017] Radar Unit In some embodiments, the radar unit may detect a respiration state of the subject. In some embodiments, the radar unit may detect a sleep state of the subject. In some embodiments, the radar unit for respiration detection is a first radar unit, and the radar unit for sleep detection unit is a second radar unit. In some embodiments, one single radar unit is provided to serve, or is configured, both to detect the respiration state of the subject and to detect the sleep state of the subject. Thereby, for example, the entire apparatus may be designed small and compact.

[0018] The radar unit may be a microwave radar unit. The radar unit may be a millimeter-wave radar unit. The radar unit may be an ultra-wideband millimeter-wave radar unit.

[0019] A millimeter-wave radar unit may be used to obtain vital information such as information related to respirations and heartbeats. In general, the chest moves about some millimeters with normal respirations, and about some tens of micrometers with heartbeats. Movements of those amplitudes can be detected as time-change in the phase of the radar signal.

[0020] The radar unit may include, or may be connected to, one or more transmitting antennas and one or more receiving antennas. The transmitting antenna is configured to transmit one or more microwaves or millimeter waves. The transmitting antenna is configured to adjust its transmitting direction towards a subject, or to transmit the microwaves or millimeter waves to the subject. The receiving antenna is configured to receive microwaves or millimeter waves reflected from the subject.

[0021] The radar unit may have multiple transmitting antennas and multiple receiving antennas. According to MIMO (Multiple-input-multiple-output) method, n channels of transmitting antennas and m channels of receiving antennas constitutes n x m channels of virtual array antennas, which allows the received waves of the virtual array antennas to be sampled at a high rate and multiple I-Q (in-phase)-Q(quadrature) data to be generated, for each transmission unit (for example, a chirp set). Multiple chirp sets are continuously transmitted in series. Thus the obtained IQ data forms a radar cube of the direction of the sampling direction which corresponds to the distance, the virtual array antennas which correspond to the direction, and the number of chirp sets which corresponds to the time. By Fast Fourier transformation (FFT) of the distance and the direction the IQ data of the target can be specified.

[0022] The controller may be configured to select radar signals from one or more antenna channels or virtual array paths, based on signal quality metrics such as signal-to-noise ratio or phase stability, in order to extract vital information with enhanced precision.

[0023] By following the change of the specified IQ data in the time direction or each time frame, the phase change can be observed if the target body part is moving. Movements of a body part related to respirations and heartbeats have periodicities, which appears as a circle on a complex plane called an I-Q plot.

[0024] The trajectory of the I-Q plot can be demodulated by using, for example the arctangent demodulation (ATD), and a phase unwrapping, the movements of the subject’s skin can be obtained By applying a filtering process, the components of respirations and those of heartbeats can be separated. Thus, instantaneous respiration frequency and heart rate can be calculated. Furthermore, by a frequency analysis, each average value can be obtained.

[0025] In the above explanation, the MIMO method is used as an example only. Other methods may be employed.

[0026] In some embodiments, the radar system and the controller may be configured to select one or more positions or distances within a region of interest (ROI) on the subject's body, such as the thoracic region. The controller may then calculate phase signals from the radar signals at the selected positions or distances. This allows adaptive selection of radar signal sources that reflect physiological motion most accurately, thereby improving the sensitivity and specificity of extracted respiratory and cardiac waveforms. For example, by targeting positions closer to the heart, the controller may better capture minute skin movements associated with cardiac contraction and relaxation cycles.

[0027] In some embodiments, the radar system may include a beam-shaping element such as a lens or a horn. The beam-shaping element may be configured to form an asymmetric ultra-wideband beam having a half power beam width of 30 degrees or less in the elevational (vertical) direction and a half power beam width of more than 30 degrees in the lateral (horizontal) direction.

[0028] Such an asymmetric configuration improves spatial resolution in the vertical direction while maintaining a wide coverage in the horizontal direction. This design allows stable detection of respiratory and cardiac motion in the upper torso region, even when the subject turns slightly during sleep, while reducing unwanted reflections from surrounding objects such as bedding.

[0029] This asymmetric beam design allows stable acquisition of respiratory and cardiac motion from the upper torso region without requiring mechanical beam scanning. In contrast to systems that scan the beam across angles or directions, the present design simplifies hardware and enhances robustness in practical environments.

[0030] The microwaves or millimeter waves may be modulated to be transmitted. An example of such a modulation is a pulse modulation. The modulation may be done by using a pulse compression technique. Examples of such a pulse compression technique include, but are not limited to, m-sequence, Hadamard sequence and the like. Multiple pulses may be transmitted and received to detect the target. Phase shifts can be detected from the received signals of multiple pulses, which enables obtaining other information such as the Doppler frequency and velocity.

[0031] In some embodiments, phase signals may be calculated from the radar signals. The phase signals may be used to determine the sleep state of the subject. The phase signals may be used to calculate the amplitude of respiratory movements (also referred to as the respiratory amplitude) of the subject.

[0032] It may be determined that abnormality of respiration is occurring: if the respiratory amplitude is lower than a threshold or has decreased by an amount greater than a threshold or by a rate or ratio greater than a threshold, if the respiratory amplitude is lower than that when the subject is snoring by an amount greater than a threshold or by a rate or ratio greater than a threshold, or if the respiratory amplitude is lower than that observed a certain period of time ago by an amount greater than a threshold or by a rate or ratio greater than a threshold. A flag that a respiratory abnormality is occurring (also referred to as “respiratory abnormality flag”) may be turned on if it has been determined that abnormality of respiration is occurring, and be turned off if the respiratory amplitude is back to the normal value or if it does not fulfill the condition.

[0033] The radar unit may be a Doppler radar unit. Alternatively, the control unit is configured to calculate Doppler effects based on the radar signals from the radar unit. The frequency of the radar signal shifts in accordance with the velocity of the target.

[0034] The frequency shift is expressed by using the time differential of the phase. The Doppler velocity, which corresponds to the velocity of the target in the line-of-straight direction, can be determined by the Doppler frequency. By using a multi-static radar, the velocity vector of the target itself can be determined.

[0035] If the Doppler velocity changes in time, the time-frequency analysis is performed to separate frequency components. As an exemplary algorithm of the time-frequency analysis is short-time Fourier transform (STFT). STFT is a function of time and frequency and thus gives a spectrogram which shows the time-frequency distribution of the radar signals. Using such a spectrogram the changes in Doppler velocity can be analyzed, and micro-Doppler, or for example movements of each body part can be detected.

[0036] The Doppler velocity reflects a body movement of the subject such as movements of arms, legs, and a body rolling. Human body is a complex structure including multiple parts such as the torso, the limbs, and the head that are connected. These parts exhibit complex movements.

[0037] For example, an ultra-wide radar can be used to analyze the dimensions of space, time and distance. For example, movements of body parts can be recognized by using a time-frequency analysis. For example, movements of body parts can be recognized by applying a convolutional neural network (CNN) to an I-Q plot of the received radar signals. Such a model using CNN can differentiate multiple gestures or movements of different body parts.

[0038] Thus, the Doppler shifts due to movements of those parts are useful to analyze vital information. Such methods enable analyzing the movements of each body part at a high accuracy. If such a body movement is detected, it may be determined that the subject is not sleeping. Thus, the Doppler velocity is useful for the sleep stage classification or the sleep-wake classification.

[0039] In some embodiments, the phase signals may be used to obtain the heartbeat intervals. Electrocardiogram has been used to acquire the variation of heartbeat intervals or the heart rate variability. But according to some embodiments of the present disclosure, the phase signals of the Doppler signals from the subject can also be used for the sleep stage classification or the sleep-wake classification.

[0040] Sleep Status Detection Unit In some embodiments, the apparatus may include a unit configured to detect signals related to the sleep status of the subjects. In some embodiments, the unit for sleep detection, or the sleep detection unit, may be a radar unit. In some embodiments, the sleep detection unit may be a sound detection unit. The details of the sound detection unit will be explained below.

[0041] The sleep detection unit may be disposed inside the body of the apparatus, integrated in the apparatus, or attached or fixed to the apparatus. In some embodiments, the sleep detection unit may be disposed as a unit separate from the apparatus and be configured to be connected to the apparatus. The connection may be wired or wireless. The sleep detection unit may be connected to the control unit for communication. The communication may be at least data transmission from the sleep detection unit to the apparatus.

[0042] In some embodiments, the sleep detection unit may detect signals related to sleep statuses of the subject. In some embodiments, the sleep detection unit may detect signals related to movements of parts of the body. In general, large movements occur while awake. Thus, movements peculiar to sleep may be detected by judging the amplitude, the speed, the pattern and the like of movements. Examples of the parts that show typical movements of sleep include, but are not limited to, arms, legs, or the entire body. Examples of the movements include, but are not limited to, raising an arm, raising a knee, and rolling the body.

[0043] Such body movements may be detected by a radar unit. In general, such movements are fast enough, and therefore may be detected by using a Doppler velocity. Doppler velocity methods can detect movements which are faster than respiratory movements.

[0044] In some embodiments, the sleep detection unit may detect snores, breathing or respiratory sounds such as the sounds caused by air passing through the respiratory sounds or airflow sounds in the respiratory tract.

[0045] In some embodiments, the sleep detection unit may include another device such as a wearable device, an actigraphic device, a pulse wave device, and the like.

[0046] Radar Unit as Sleep Detection Unit In some embodiments, the radar unit may be used as the sleep detection unit. In general, body movements during sleep are greater than when awake. For example, the respiration speed or period is smaller during sleep than while awake. For example, the heartbeat is smaller during sleep than while awake. Thus, millimeter-waves may be applied to a body part of the subject, and reflected waves may be detected. From the reflected waves, body movements of the subjects may be identified. It may be determined that the subject is sleeping if the body movements are smaller than a threshold, and it may be determined that the subject is sleeping if the body movements become great again.

[0047] The criterion of whether or not the subject is sleeping be set in accordance with the sleep stage. In some embodiments, the sleep stage may be determined in accordance with the body movements by using radar signals. In some embodiments, the sleep stage may be determined by using both radar signals and sound signals.

[0048] The beam shaping technique described above may also enhance the detection of in-bed presence and body movements during sleep. A wider lateral beam supports robust detection of large body motions such as rolling, while a narrow elevational beam prevents interference from external movements, making sleep-wake classification more reliable.

[0049] Relationship Between Occurrence of Sleep Apnea or Hypopnea and Cardiovascular Disorder In some embodiments, the detection of sleep apnea or hypopnea may not be performed for just one occurrence. The detection of sleep apnea or hypopnea may be continued for a certain period of time, or for a “session” or “detection session”. For example, the detection of sleep apnea or hypopnea may be continued for a time during which the subject is supposed to sleep even though the subject wakes up, stays awake, is sleeping, or is not in a sleeping state. For example, the detection session corresponds to a time during which the subject is in bed, or a “bedtime”.

[0050] The number of times of apnea and / or hypopnea may be counted for a sleeping time. The number of times that an occurrence of apnea or hypopnea is detected in one detection session may be obtained.

[0051] A frequency of apnea or hypopnea may be obtained as the number of apneas or hypopneas divided by the duration of the detection session. Such a frequency may be used as an index. For example, the frequency of apnea or hypopnea may be called an index of sleep apnea or hypopnea or a sleep apnea or hypopnea index (AHI).

[0052] The frequency of apnea or hypopnea may be related to cardiovascular disorders. Patients with heart failure or impaired left ventricle function are more likely to develop pulmonary congestion. Pulmonary congestion increases pulmonary artery pressure. Pulmonary congestion, on the other hand, causes a decrease in partial pressure of CO2(PaCO2) in the blood and thus increases the likely hood of causing central sleep apnea (CSA). Thus, CSA are associated with cardiovascular disorders such as heart failure diseases.

[0053] The relationship between the apnea-hypopnea index (AHI) and PCWP may be obtained by a statistical study, and predetermined (for example, see NPL 4).

[0054] Actual PCWP data may be obtained by performing pressure measurements by use of a catheter on the right side of the heart of congestive heart failure patients who provided written informed consent. AHI data may be obtained by performing overnight sleep studies on the same patients. The sleep studies may be performed for multiple nights, for a month, for multiple weeks, or for multiple months.

[0055] The sleep studies may be carried out by performing multiple measurements. Examples of such measurements include the determination of sleep stages by using electro-oculograms, submental electromyogram, or the like, the heart recordings, the SpO2and PCO2measurements, and the chest abdominal measurement using respiratory effort bands, the oronasal airflow monitoring by thermocouples and the snoring monitoring by a piezo snore sensor, and the like. The above-mentioned acquisition methods of PCWP and AHI data are shown as examples and not to exclude other methods or data types from the present disclosure.

[0056] In some embodiments, the relationship between AHI and PCWP may be a substantially linear or monotonous relationship between AHI and PCWP. In some embodiments, the relationship between AHI and PCWP may be an amount of change in PCWP with respect to an amount of change in AHI.

[0057] The relationship may be expressed by an equation, a function, or an association table. The relationship may not be expressed in a quantitative fashion but expressed in a qualitative fashion, e.g. by an expression such as “decrease” or “increase” of one parameter with respect to “decrease” or “increase” of the other parameter. For example, a decrease of AHI may correspond to a decrease of PCWP.

[0058] An index related to a cardiovascular disorder may be obtained or calculated by using the obtained frequency of occurrence of sleep apnea or hypopnea of the subject and the predetermined relationship between the frequency of occurrence of sleep apnea or hypopnea and the cardiovascular disorder. For example, if an AHI of the subject is obtained for a certain detection session, the predetermined relationship between the AHI and PCWP is used to estimate a PCWP of the subject, in other words, to estimate a PCWP which would be obtained by performing a catheterization method at or around the time of the same detection session.

[0059] In the case of CSA, the amplitude of the chest movement of breathing decreases only gently. For example, Cheyne-Stokes breathing which occurs before apnea occurs does not generate snoring, and its amplitude gradually decreases. Such a gradual change in breathing amplitude can be detected and followed by using radar detection techniques.

[0060] In some embodiments, a cardiovascular index (CDV index) may be a PCWP. In some embodiments, a CDV index may be an index of one of the cardiovascular disorders such as left ventricular filling pressure, left atrial pressure, left ventricular preload, mitral valve function, severity of congestive heart failure, and the like.

[0061] The value of left ventricular filling pressure, left atrial pressure, or left ventricular preload itself may be the index.

[0062] Examples of indices of mitral valve function include, but are not limited to: indices by echocardiography such as regurgitation (volume and velocity) by observing the motion of the mitral valve, stenosis (degree of narrowing and flow rate), and valve morphology (size); indices by cardiac catheterization such as pressure gradients across the valve and the volume of regurgitation; and indices by cardiac MRI such as valve morphology (size), motion (velocity), and the presence of regurgitation, by the high-resolution imaging.

[0063] Examples of indices of severity of congestive heart failure include: indices by echocardiography such as left ventricular systolic function (ejection fraction, size of the left ventricle), diastolic function, ventricular wall thickness, regional wall motion abnormalities, and pulmonary artery pressure; indices by cardiac catheterization such as pressures in different parts of the heart, cardiac output, and systemic vascular resistance to quantitatively assess heart failure severity; indices by cardiac MRI such as left ventricular systolic function, myocardial quality (such as fibrosis or scarring), and levels of myocardial stress markers; and indices by blood tests such as levels of biomarkers such as brain natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP).

[0064] Stimulation Unit In some embodiments, the apparatus may include a unit configured to apply stimulations to the subjects. The degree of the stimulation to be applied is adjusted as not to waken the subject or as to cause a micro-arousal for the subject. In some embodiments, the apparatus may not include a stimulation unit or be configured without a stimulation unit.

[0065] In some embodiments, the unit for stimulation application, or the stimulation unit, may cause auditory stimulations, tactile stimulation, visual or light stimulations, electric stimulations, heat stimulations, vibrations, and the like. The stimulation unit may be a speaker which causes sounds as auditory stimulations.

[0066] The examples of sounds include, but are not limited to a low frequency sound, ultrasound, audible sound. In some examples, the frequency may be set outside of an audible range. In some examples, the frequency may be set at a low part of the audible range. In some examples, the frequency may be set between 30 Hz and 60 Hz. A non-audible sound may not be heard by others, or non-subject persons, who are present near the subject. A low frequency sound in the audible range may least impact the non-subject persons near the subject.

[0067] In some embodiments, the stimulation sound may be a chirp signal or a sweep signal. The chirp signal may be an up-chirp signal, a down-chirp signal, or a combination of the two. An example of the stimulation sound may be a chirp signal starting at 30 Hz and increasing to 60 Hz.

[0068] The stimulation unit may be a fan which generates winds as tactile stimulations. The stimulation unit may be a light source which generates lights. The lights to be emitted may be a flashlight, light pulses, or the like. The stimulation unit may be an electric stimulator that generate an electric current so as to flow through a part of the subject’s body in contact therewith. The electric current may be a galvanic current, electric pulses, or the like. The stimulation may be a thermal stimulation. A heating element may be attached to a skin or the cloth of the subject and be heated. A heated element may be brought into contact with the subject. The stimulation may be vibrations. A vibrator may be attached to a skin or the cloth of the subject or disposed near the subject.

[0069] In some embodiments, if an occurrence of apnea or hypopnea is detected, the control unit may send a command to the stimulation unit to apply a stimulation to the subject. The control unit may send a command to apply a stimulation to the subject only after a certain period of time from the point of time when the occurrence of apnea or hypopnea is detected. This can avoid too frequent applications of stimulation, which can happen if the decision of respiration abnormality is set to be highly sensitive. On the other hand, it should not wait for too long a time, because it could oversee a respiratory arrest. The holding time may preferably be set between one second and 3 seconds.

[0070] Control Unit In some embodiments, the control unit is configured to communicate with, to receive information and signals from, to send information, signals, instructions and orders to, and / or to control, the radar unit. In some embodiments, the control unit may control a stimulation unit. In some embodiments, the control unit may perform necessary processing by controlling the units or parts configured in the control unit.

[0071] The control unit may include a circuitry. The control unit may include a processor or a processing unit. The processing unit may be a central processing unit (CPU). The processing unit may include an arithmetic logic unit, a microprocessor, a general-purpose controller, a single core or multicore processor, or multiple processors for parallel computations.

[0072] The control unit may include or be connected to a storage. The storage may be a non-transitory storage medium that stores programs and data for providing the functionality described herein. The storage may be, but is not limited to, a dynamic random access memory (DRAM) device, a static random access memory (SRAM), a flash memory, or some other memory devices. In some embodiments, the storage may be a non-volatile memory or a similar permanent storage device or media. Examples of such a storage include, but are not limited to, a hard disk device, a floppy disk device, a CD-ROM device, a DVD-ROM device, a DVD-RAM device, a DVD-RW device, a magnetic-tape data storage device, and some other mass storage device for storing information on a more permanent basis.

[0073] The control unit may include or be connected to a memory. The memory may store instructions and data that may be executed by the processing unit. The instructions and data may include codes for performing the techniques described herein. The processing unit may move the programs and data stored in the storage to the memory, and execute and use them. The memory may be a cache memory. The memory may be, but is not limited to, a dynamic random access memory (DRAM) device, a static random access memory (SRAM), a flash memory, or some other memory devices.

[0074] In some embodiments, the control unit may have a timer or a timer function. The timer may be a hardware timer. The timer may be a software timer.

[0075] In some embodiments, the control unit is configured to receive from the respiration detection unit the detected signal related to the respiratory movement of the subject. It may also determine an amplitude of the respiratory movement of the subject. In some embodiments, the control unit is configured to receive from the sleep detection unit the signal related to the sleep status of the subject. It may also determine a sleep-wake state of the subject.

[0076] Some embodiments and examples of the present disclosure will now be discussed in detail by referring to the following figures. The embodiments and examples, with reference to the accompanying drawings, are given as examples only, and they should not be interpreted as being limiting. FIG. 1 shows a flowchart of a process for estimating a cardiovascular disorder index from respiratory and sleep signals, according to an embodiment. FIG. 2 shows a flowchart of a process for correlating apnea-hypopnea index (AHI) and PCWP over multiple sessions, according to an embodiment. FIG. 3 shows a schematic diagram of an apparatus for non-invasive acquisition of respiratory and cardiac motion. FIG. 3A shows a schematic diagram of an embodiment of an apparatus including a beam-shaping element such as a lens for focused radar transmission and reception toward a region of interest (ROI) located in a thoracic region of a subject. FIG. 4 shows a block diagram of an apparatus, showing functional units such as a radar unit, control circuitry, and storage.

[0077] Embodiment of Process 1 FIG. 1 shows a flowchart S100 of steps of obtaining an index related to a cardiovascular disorder (CVD) according to an embodiment.

[0078] The detection session of occurrences of apnea or hypopnea is started (S110). The condition to end this detection session (S116) is set.

[0079] Radio waves are transmitted to the subject and the radio waves reflected from the subject are received (S111). Based on the reflected radio waves, the amplitude of the respiratory movement is calculated (S112), and the sleep-wake state of the subject is determined (S113).

[0080] Based on the calculated respiratory amplitude and the sleep-wake state, it is determined whether apnea or hypopnea is occurring (S115). For example, if the respiratory amplitude is smaller than a threshold and the subject is sleeping, it is determined that apnea or hypopnea is occurring.

[0081] If it is determined whether apnea or hypopnea is occurring, it is counted as one “occurrence of apnea or hypopnea” (S115). Please note that the occurrence(s) of apnea or hypopnea is referred to as “AH occurrence” in FIGS. 1, 2 and 4. For example, one occurrence of apnea or hypopnea is determined by a period during which apnea or hypopnea is continuously occurring. If apnea or hypopnea stops, the period of the occurrence of apnea or hypopnea ends. For example, such occurrences can be observed multiple times for one night.

[0082] If the predetermined condition is not yet met (S116), the detection of occurrences of apnea or hypopnea (S110~S116) is repeated. If the predetermined condition is met, the detection of occurrences of apnea or hypopnea (S110~S116) ends (S116).

[0083] The frequency of the occurrences of apnea or hypopnea is calculated by dividing the total number of the counts or the occurrences of apnea or hypopnea during the detection session divided by the duration of the detection session (S120).

[0084] The relationship between the frequency of the occurrences of apnea or hypopnea and the index of the cardiovascular disorder is referred to (S130).

[0085] Based on the calculated frequency of the occurrences of apnea or hypopnea and the relationship, the index of the cardiovascular disorder is estimated (S140).

[0086] Embodiment of Process 2 FIG. 2 shows a flowchart S200 of steps of obtaining an index related to a cardiovascular disorder (CVD) according to an embodiment.

[0087] The detection session of occurrences of apnea or hypopnea is started (S210). The condition to end this detection session (S216) is set.

[0088] Radio waves are transmitted to the subject and the radio waves reflected from the subject are received (S211). Based on the reflected radio waves, the amplitude of the respiratory movement is calculated (S212), and the sleep-wake state of the subject is determined (S213).

[0089] Based on the calculated respiratory amplitude and the sleep-wake state, it is determined whether apnea or hypopnea is occurring (S215). For example, if the respiratory amplitude is smaller than a threshold and the subject is sleeping, it is determined that apnea or hypopnea is occurring.

[0090] If it is determined whether apnea or hypopnea is occurring, it is counted as one “occurrence of apnea or hypopnea” (S215).

[0091] If the predetermined condition is not yet met (S216), the detection of occurrences of apnea or hypopnea (S210~S216) is repeated. If the predetermined condition is met for the first time, the detection of occurrences of apnea or hypopnea (S210~S216) ends (S216).

[0092] The frequency of the occurrences of apnea or hypopnea is calculated by dividing the total number of the counts or the occurrences of apnea or hypopnea during the detection period divided by the duration of the detection period (S221). In this embodiment, the frequency of the occurrences of apnea or hypopnea is referred to as “apnea or hypopnea index” (AHI). The AHI obtained for the initial detection session is referred to as “initial AHI” or “first (1st) AHI”.

[0093] In parallel to the first detection session, the PCWP is measured by using a catheterization method applied to the subject (S231). In this way, the relationship between the first AHI and the measured PCWP is obtained for the subject (S232).

[0094] Following the initial detection session, subsequent detection sessions (S210 ~ S216) are carried out or repeated. For the n-th detection session, the n-th AHI is obtained (S222).

[0095] Based on the n-th AHI the relationship between the first AHI and the corresponding PCWP, the PCWP at the time of the n-th detection session is estimated (S240). In general, there is a linear or monotonous relationship between the AHI and the PCWP. Therefore, for example, if the n-th AHI is smaller than the first AHI, the real PCWP for the n-th detection session (hereinafter also referred to as “n-th PCWP”) is expected to be smaller than the measured PCWP. As an example, a quantitative value of PCWP may be estimated.

[0096] The PCWP has been measured in a very invasive manner, e.g. by using a catheterization method. Methods according to the present embodiment minimizes the number of invasive PCWP measurements, and enables a much less invasive assessment of the PCWP.

[0097] Embodiment of Apparatus 1 FIG. 3 shows a schematic diagram of an apparatus 300 according to an embodiment, to explain the functions of the apparatus and the interaction thereof with a subject 370.

[0098] The apparatus 300 includes a control unit 310, a radar unit 320 which functions as a respiration detection unit and a sleep detection unit.

[0099] The radar unit 320 has multiple transmitting antennas 321 and multiple receiving antennas 323. The control unit 310 instructs the radar unit 320 to transmit radio waves 322 from the transmitting antennas 321 towards the subject 370. The radio waves 324 reflected by the body surface (typically the chest) of the subject 370 are detected by the receiving antennas 323. The radar unit 320 converts the detected signals to communication signals and sends the same to the control unit 310.

[0100] The control unit 310 receives the information sent from the radar unit 320. Based on the received information, the control unit 310 determines or judges whether there is an occurrence of apnea or hypopnea.

[0101] Each time it is determined or judged that there is an occurrence of apnea or hypopnea, the control unit 310 counts it as one occurrence of apnea or hypopnea. This detection session of occurrences of apnea or hypopnea is continued for a predetermined period of time. When the detection session ends, the frequency of the occurrences of apnea or hypopnea is calculated by dividing the total number of the counts or the occurrences of apnea or hypopnea during the detection session divided by the duration of the detection session.

[0102] Embodiment of Apparatus 2 FIG. 3A shows a schematic diagram of another embodiment of an apparatus 300A configured to transmit a radio wave toward a region of interest 371A located in the thoracic region of a subject 370A.

[0103] The apparatus 300A includes a radar unit 320A and a control unit 310A. The radar unit 320A includes multiple transmitting antennas 321A and receiving antennas 323A. A beam-shaping element 330A such as a lens is disposed between the antennas and the subject 370A. The beam-shaping element 330A is configured to form a directional beam having a relatively wide beam width in the lateral direction and a narrower beam width in the elevational direction.

[0104] The control unit 310A instructs the radar unit 320A to transmit radio waves 322A from the transmitting antennas 321A. These waves pass through the beam-shaping element 330A and are directed toward the region of interest 371A. The radio waves 324A reflected from the region of interest pass again through the beam-shaping element 330A and are received by the receiving antennas 323A. The radar unit 320A converts the received signals into radar signals and transmits them to the control unit 310A. The lens may have a half power beam width of 30 degrees or less in the vertical direction and more than 30 degrees in the horizontal direction.

[0105] The control unit 310A receives the radar signals and calculates phase signals at multiple positions or distances within the region of interest 371A. The control unit 310A may select an optimal phase signal based on signal quality, and calculate a respiratory amplitude and / or heartbeat interval based on the selected phase signal. These values may be used for determining the occurrence of sleep apnea or hypopnea and for estimating a cardiovascular disorder related index.

[0106] The control unit may evaluate the signal quality (e.g., SNR, phase stability, or amplitude consistency) at each selected position or distance, and may adaptively select the optimal position or distance from which to extract phase signals. This adaptive selection improves the accuracy and robustness of the estimated heartbeat intervals and respiratory intervals.

[0107] Embodiment of Apparatus 1-1 FIG. 4 shows a block diagram of a sleep apnea treatment apparatus 400 according to an embodiment. This embodiment may be employed to the above explained Apparatus Embodiment 1. The apparatus 400 includes a control unit 410, and a radar unit 420. In FIG. 4, the apparatus 400 further includes a communication unit 450 or an I / O port to communicate with external devices or a network, and a display 460. The control unit 410 includes a process unit 411, a memory 412 and a storage 413. These units and components can communicate with each other via a bus 470.

[0108] The storage 413 is a non-transitory computer readable memory that stores a program code 413a to be executed by the process unit 411 to perform the steps explained in the present embodiment and a relationship between the frequency of the occurrences of apnea and hypopnea and the index related to the cardiovascular disorder 413b.

[0109] The process unit 411 includes an apnea or hypopnea detection session control part 411a, a radar transmission order part 411b, a phase signal calculation part 411c, a respiratory amplitude calculation part 411d, a sleep stage determination part 411e, an apnea or hypopnea occurrence determination part 411f, an apnea or hypopnea occurrence counter 411g, an apnea or hypopnea frequency calculation part 411h, and a cardiovascular disorder index obtainment part 411i.

[0110] The AH detection session control part 411a receives information including the conditions for starting an AH detection session and for ending it. Typically the condition may include the starting time and the ending time. The starting time may be the time when the subject goes to bed. The ending time may be the time when the subject goes out of bed. The AH detection session control part 411a may use the radar signals obtained by the radar unit 420 to judge when the subject is in bed, when the subject goes to bed, when the subject goes out of bed, and the like.

[0111] In some embodiments, one AH detection session may be one night. In some embodiments, one AH detection session may include multiple nights, for example, three nights, multiple nights over a week, over multiple weeks, over a month, over multiple months. In some embodiments, one AH detection session may include multiple nights that are not consecutive. In some embodiments, one AH detection session may include a non-night or day-time zone in accordance with the subject’s sleeping time.

[0112] In FIG. 4, the radar unit 420 is an ultra-wideband millimeter-wave radar unit. The radar unit 420 includes multiple transmitting antennas 421 and multiple transmitting antennas 423.

[0113] The radar transmission order part 411b sends a signal or an order to the radar unit 420 to transmit ultra-wideband millimeter-waves.

[0114] Upon receiving the order from the radar transmission order part 411b, each of the multiple transmitting antennas 421 transmit its respective ultra-wideband millimeter-waves to a subject (not shown). The ultra-wideband millimeter-waves are modulated by using a pulse compression technique such as m-sequence.

[0115] The transmitted ultra-wideband millimeter-waves are reflected at the body surface of the subject. Each of the multiple receiving antennas 421 receives its respective ultra-wideband millimeter-waves. The radar unit 420 sends the information of the received radar signals to the memory 412, to store the information therein as radar signals.

[0116] The phase signal calculation part 411c refers to the radar signals stored in the memory 412 and calculates the phase signal of each of the radar signals, or each of the radar signals from the respective receiving antennas.

[0117] The radar signals received from the radar unit may be stored temporarily in the memory, which is accessible by the control unit. The control unit may retrieve the stored radar signals and process them to calculate the phase signals and other derived parameters.

[0118] The respiratory amplitude calculation part 411d refers to the phase signals calculated by the phase signal calculation part 411c, and calculates the respiratory amplitude, or the amplitude of respiration movements of the body part of interest.

[0119] The sleep stage determination part 411e refers to the phase signals calculated by the phase signal calculation part 411c, which determines whether the subject is sleeping or awake. For example, the radar signals include large movements of a body part compared to a reference, it determines that the subject is not sleeping, awake, or in a wake state. For example, the radar signals do not include large movements of a body part compared to a reference, it determines that the subject is sleeping, or in a sleep state.

[0120] The apnea or hypopnea occurrence determination part 411f refers to the outputs of the respiration state determination part 411d and the sleep stage determination part 411f. If the obtained respiratory amplitude is smaller than a threshold and the subject is sleeping, in other words, if both of the two conditions have been fulfilled, the apnea or hypopnea occurrence determination part 411h determines or judges that it is an occurrence of apnea or hypopnea for the subject.

[0121] The apnea or hypopnea occurrence counter 411g counts each time an occurrence of apnea or hypopnea is detected, as one occurrence of apnea or hypopnea or one AH occurrence.

[0122] The AH detection session control part 411a recognizes the ending condition of the AH occurrence detection session and ends the session. Then the apnea or hypopnea frequency calculation part 411h calculates the frequency of the occurrence of apnea or hypopnea during the detection session. Typically, the apnea or hypopnea frequency calculation part 411h divides the number of the occurrences of apnea or hypopnea detected during the detection session by the duration of the detection session. This frequency may be called an apnea or hypopnea index (AHI).

[0123] The cardiovascular disorder index obtainment part 411i refers to the relationship data between the frequency of the occurrence of apnea or hypopnea and the index related to the cardiovascular disorder of interest, and obtains the index related to the cardiovascular disorder of interest for the subject.

[0124] The present disclosure also provides following embodiments: A001. An apparatus for acquiring vital information related to a cardiovascular disorder, comprising: a radar system configured to transmit a radio wave to a subject and receive the radio wave reflected by the subject; a controller configured to: (a) calculate a respiratory amplitude, based on the radio wave reflected by the subject, (b) determine a sleep status of the subject, based on the radio wave reflected by the subject, (c) judge an occurrence of sleep apnea or hypopnea, based on the respiratory amplitude and the sleep-wake state, (d) obtain a frequency of the occurrences of sleep apnea or hypopnea, and (e) obtain a cardiovascular disorder related index (CVDI), based on a relationship between the frequency of the occurrence of sleep apnea or hypopnea and the cardiovascular disorder. A011. The apparatus of A001 or any one of embodiments, wherein the radar system is a microwave radar system or an ultra-wideband millimeter-wave radar system. A021. The apparatus of A001 or any one of embodiments, wherein the circuitry further configured to: convert the received microwave to a radar signal, select a position of a region of interest of the subject or a distance between the radar system to the region of interest of the subject, calculate a phase signal from the radar signal at the selected position or at the selected distance, calculate the respiratory amplitude from the phase signal, and determine the sleep state of the subject from the phase signal. A031. The apparatus of A001 or any one of embodiments, wherein the subject has a heart failure or has a mild symptom of a heart failure. A041. The apparatus of A001 or any one of embodiments, wherein the index is a pulmonary capillary wedge pressure. A042. The apparatus of A001 or A041, or any one of embodiments, wherein the index is related to a cardiovascular disorder selected form the group consisting of a left ventricular filling pressure, a left atrial pressure, a left ventricular preload, a mitral valve function, and a severity of congestive heart failure. A043. The apparatus of any one of A001 to A042, or any one of embodiments, wherein the index comprises a plurality of indices related to a plurality of cardiovascular disorders. A051. The apparatus of A001 or any one of embodiments, wherein said determining of the occurrence of sleep apnea or hypopnea based on the respiratory amplitude and the sleep status comprises determining that sleep apnea or hypopnea is occurring when the respiratory amplitude decreases and when the subject is sleeping. A061. The apparatus of A001 or any one of embodiments, wherein the relationship between the occurrence of sleep apnea or hypopnea and the cardiovascular disorder is a relationship between an apnea-hypopnea index and a pulmonary capillary wedge pressure. A071. The apparatus of A001, A051, or A061 or any one of embodiments, wherein the sleep apnea is central sleep apnea (CSA), and / or the sleep hypopnea is central sleep hypopnea (CSH). A081. The apparatus of A001 or any one of embodiments, wherein the circuitry further configured to calculate a probability of developing a heart failure and / or an acute exacerbation of heart failure. A082. The apparatus of A001 or any one of embodiments, wherein the circuitry is further configured to: estimate a severity of sleep apnea, and based on the estimated severity of sleep apnea, generate a diagnostic result and an appropriate treatment. A083. The apparatus of A001 or any one of embodiments, wherein the circuitry is further configured to: receive a treatment history of the subject, and calculate a probability of developing a heart failure and / or an acute exacerbation of heart failure. A084. The apparatus of A001 or any one of embodiments, wherein the controller is further configured to calculate a possibility of pulmonary congestion and / or congestive heart failure.A085. The apparatus of A001 or any one of embodiments, wherein the controller is further configured to calculate an appropriate dosage of diuretics. A091. The apparatus of A001 or any one of embodiments, further comprising a stimulation device, wherein the controller further configured to: determine whether sleep apnea or hypopnea is occurring, and if it is determined that sleep apnea or hypopnea is occurring, send an order to the stimulation device to apply a stimulation to the subject. A092. The apparatus of A091 or any one of embodiments, wherein the stimulation is selected from the group consisting of a low-frequency sound, an infrasound, an ultrasound, an audible sound, a vibration, a wind flow, a light stimulation, a thermal stimulation, and an electrical stimulation. A101. The apparatus of A001 or any one of embodiments, wherein the radar system is configured to direct the radio wave toward a region of interest on the subject's body, such as a thoracic region, and wherein the radar system comprises a beam-shaping element configured to form a directional beam having a relatively wide beam width in a lateral direction and a narrower beam width in an elevational direction. A102. The apparatus of A101 or any one of embodiments, wherein the controller is configured to select one or more positions or distances within the region of interest and calculate phase signals from radar signals at the selected positions or distances, so as to extract heartbeat intervals and / or respiratory intervals with improved signal quality. A103. The apparatus of A101 or any one of embodiments, wherein the beam-shaping element comprises a lens or a horn configured to form a beam having different lateral and elevational beam widths. A104. The apparatus of A103 or any one of embodiments, wherein the beam-shaping element is configured to provide a lateral beam width sufficient to detect the subject even when the subject turns during sleep. A105. The apparatus of A102 or any one of embodiments, wherein the controller is configured to select an optimal position or distance within the region of interest based on a signal quality indicator to calculate the phase signal. A106. The apparatus of A101 or any one of embodiments, wherein targeting the region of interest improves a signal-to-noise ratio of the respiratory amplitude or heartbeat interval estimation. A107. The apparatus of A103, wherein the beam-shaping element is configured to form a beam having a half power beam width of 30 degrees or less in a vertical direction and more than 30 degrees in a horizontal direction. A001b. An apparatus for acquiring vital information related to a cardiovascular disorder, comprising: a radar system configured to transmit a microwave to a subject and receive the microwave reflected by the subject; a circuitry configured to: (a) calculate a respiratory amplitude, based on the radio wave reflected by the subject, (b) determine a sleep status of the subject, based on the radio wave reflected by the subject, (c) judge an occurrence of sleep apnea or hypopnea, based on the respiratory amplitude and the sleep-wake state, (d) obtain a frequency of the occurrence of sleep apnea or hypopnea, and (e) obtain a cardiovascular disorder related index (CVDI), based on a relationship between the frequency of the occurrence of sleep apnea or hypopnea and the cardiovascular disorder. B001. A method for acquiring vital information related to a cardiovascular disorder, comprising: causing a radar system to transmit a microwave to a subject; causing the radar system to receive the microwave reflected by the subject; calculating a respiratory amplitude, based on the radio wave reflected by the subject; determining a sleep status of the subject, based on the radio wave reflected by the subject; determining an occurrence of sleep apnea or hypopnea based on the respiratory amplitude and the sleep status; obtaining a frequency of the occurrences of sleep apnea or hypopnea; and obtaining a cardiovascular disorder related index, based on a relationship between the frequency of the occurrences of sleep apnea or hypopnea and the cardiovascular disorder. C001. A software program configured to cause a computer to execute the method of B001 or B011. D001. A non-transitory storage medium storing the software program of C001.

[0125] Terms and phrases used in this application, and variations thereof, especially in the appended claims, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing, the term ‘including’ should be read to mean ‘including, without limitation,’ ‘including but not limited to,’ or the like; the term ‘comprising’ as used herein is synonymous with ‘including,’ ‘containing,’ or ‘characterized by,’ and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps; the term ‘having’ should be interpreted as ‘having at least;’ the term ‘includes’ should be interpreted as ‘includes but is not limited to;’ the term ‘example’ is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof.

[0126] A group of items linked with the conjunction ‘and’ should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as ‘and / or’ unless expressly stated otherwise. Similarly, a group of items linked with the conjunction ‘or’ should not be read as requiring mutual exclusivity among that group, but rather should be read as ‘and / or’ unless expressly stated otherwise.

[0127] With respect to the use of substantially any plural and / or singular terms herein in the English language, those having skill in the art can translate from the plural to the singular and / or from the singular to the plural as is appropriate to the context and / or application. The various singular / plural permutations may be expressly set forth herein for sake of clarity. The indefinite article “a” or “an” does not exclude a plurality.

[0128] Any of the embodiments or any of the aspects disclosed herein is independently combinable, partly or wholly with other embodiments described herein in any way, e.g., one, two, or three or more embodiments may be combinable in whole or in part. Further, any of the features of any of the embodiments or any of the aspects disclosed herein is applicable to any of the other embodiments and aspects, or may be made optional to other embodiments or aspects.

[0129] While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. It is not intended that the invention be limited by the specific examples provided within the specification. While the invention has been described with reference to the aforementioned specification, the descriptions and illustrations of the embodiments herein are not meant to be construed in a limiting sense. Numerous variations, changes, and substitutions may now occur to those skilled in the art without departing from the invention. Furthermore, it shall be understood that all aspects of the invention are not limited to the specific depictions, configurations or relative proportions set forth herein which depend upon a variety of conditions and variables. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is therefore contemplated that the invention shall also cover any such alternatives, modifications, variations or equivalents. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims

1. An apparatus for acquiring vital information related to a cardiovascular disorder, comprising: a radar system configured to transmit a radio wave to a subject and receive the radio wave reflected by the subject; a controller configured to: (a) calculate a respiratory amplitude, based on the radio wave reflected by the subject, (b) determine a sleep status of the subject, based on the radio wave reflected by the subject, (c) judge an occurrence of sleep apnea or hypopnea, based on the respiratory amplitude and the sleep state, (d) obtain a frequency of the occurrences of sleep apnea or hypopnea, and (e) obtain a cardiovascular disorder related index (CVDI), based on a relationship between the frequency of the occurrence of sleep apnea or hypopnea and the cardiovascular disorder.

2. The apparatus of claim 1, wherein the radar system is a microwave radar system or an ultra-wideband millimeter-wave radar system.

3. The apparatus of claim 1, wherein the circuitry further configured to: convert the received microwave to a radar signal, select a position of a region of interest of the subject or a distance between the radar system to the region of interest of the subject, calculate a phase signal from the radar signal at the selected position or at the selected distance, calculate the respiratory amplitude from the phase signal, and determine the sleep state of the subject from the phase signal.

4. The apparatus of claim 1, wherein said determining of the occurrence of sleep apnea or hypopnea based on the respiratory amplitude and the sleep status comprises determining that sleep apnea or hypopnea is occurring when the respiratory amplitude decreases and when the subject is sleeping.

5. The apparatus of claim 1, wherein the relationship between the occurrence of sleep apnea or hypopnea and the cardiovascular disorder is a relationship between an apnea-hypopnea index and a pulmonary capillary wedge pressure.

6. The apparatus of claim 1, wherein the index is a pulmonary capillary wedge pressure.

7. The apparatus of claim 6, wherein the index is related to a cardiovascular disorder selected form the group consisting of: a left ventricular filling pressure, a left atrial pressure, a left ventricular preload, a mitral valve function, and a severity of congestive heart failure.

8. The apparatus of claim 1, wherein the circuitry is further configured to: estimate a severity of sleep apnea, and based on the estimated severity of sleep apnea, generate a diagnostic result and an appropriate treatment.

9. The apparatus of claim 1, wherein the circuitry is further configured to: receive a treatment history of the subject, and calculate a probability of developing a heart failure and / or an acute exacerbation of heart failure.

10. The apparatus of claim 1, wherein the controller is further configured to calculate an appropriate dosage of diuretics.

11. The apparatus of claim 1, wherein the radar system is configured to direct the radio wave toward a region of interest on the subject's body, such as a thoracic region, and wherein the radar system comprises a beam-shaping element configured to form a directional beam having a relatively wide beam width in a lateral direction and a narrower beam width in an elevational direction.

12. The apparatus of claim 11, wherein the controller is configured to select one or more positions or distances within the region of interest and calculate phase signals from radar signals at the selected positions or distances, so as to extract heartbeat intervals and / or respiratory intervals with improved signal quality.

13. The apparatus of claim 11, wherein the beam-shaping element comprises a lens or a horn configured to form a beam having different lateral and elevational beam widths.

14. The apparatus of claim 13, wherein the beam-shaping element is configured to provide a lateral beam width sufficient to detect the subject even when the subject turns during sleep.

15. The apparatus of claim 12, wherein the controller is configured to select an optimal position or distance within the region of interest based on a signal quality indicator to calculate the phase signal.

16. The apparatus of claim 11, wherein targeting the region of interest improves a signal-to-noise ratio of the respiratory amplitude or heartbeat interval estimation.

17. The apparatus of claim 13, wherein the beam-shaping element is configured to form a beam having a half power beam width of 30 degrees or less in a vertical direction and more than 30 degrees in a horizontal direction.

18. The apparatus of claim 1, further comprising a stimulation device, wherein the controller further configured to: determine whether sleep apnea or hypopnea is occurring, and if it is determined that sleep apnea or hypopnea is occurring, send an order to the stimulation device to apply a stimulation to the subject.

19. The apparatus of claim 18, wherein the stimulation is selected from the group consisting of a low-frequency sound, an infrasound, an ultrasound, an audible sound, a vibration, a wind flow, a light stimulation, a thermal stimulation, and an electrical stimulation.

20. A method for acquiring vital information related to a cardiovascular disorder, comprising: causing a radar system to transmit a microwave to a subject; causing the radar system to receive the microwave reflected by the subject; calculating a respiratory amplitude, based on the radio wave reflected by the subject; determining a sleep status of the subject, based on the radio wave reflected by the subject; determining an occurrence of sleep apnea or hypopnea based on the respiratory amplitude and the sleep status; obtaining a frequency of the occurrences of sleep apnea or hypopnea; and obtaining a cardiovascular disorder related index, based on a relationship between the frequency of the occurrences of sleep apnea or hypopnea and the cardiovascular disorder.

21. A software program configured to cause a computer to execute the method of claim 20.

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