Abstract: A system and method for managing preload reserve and tracking the inotropic state of a patient's heart. The S1 heart sound is measured as a proxy for direct measurement of stroke volume. The S3 heart sound may be measured as a proxy for direct measurement of preload level. The S1-S3 pair yield a point on a Frank Starling type of curve, and reveal information regarding the patient's ventricular operating point and inotropic state. As an alternative, or in addition to, measurement of the S3 heart sound, the S4 heart sound may be measured or a direct pressure measurement may be made for the sake of determining the patient's preload level. The aforementioned measurements may be made by a cardiac rhythm management device, such as a pacemaker or implantable defibrillator.

Abstract: A system, method, or device monitor a force-frequency relationship exhibited by a patient's heart. A contractility characteristic, such as a heart sound characteristic of an S1 heart sound, is measured. The contractility characteristic indicates the forcefulness of a contraction of the heart. The frequency at which the heart is contracting is determined. A group of (contractility characteristic, heart rate) pairs is stored in a memory device. The group of pairs defines a force-frequency relationship for the heart. The method may be implemented by an implantable device, or by a system including a implantable device.

Abstract: A system comprising an implantable medical device (IMD) includes an implantable heart sound sensor to produce an electrical signal representative of at least one heart sound. The heart sound is associated with mechanical activity of a patient's heart. Additionally, the IMD includes a heart sound sensor interface circuit coupled to the heart sound sensor to produce a heart sound signal, and a signal analyzer circuit coupled to the heart sound sensor interface circuit. The signal analyzer circuit measures a baseline heart sound signal, and deems that an ischemic event has occurred using, among other things, a measured subsequent change in the heart sound signal from the established baseline heart sound signal.

Abstract: An implantable medical device (IMD) is adapted for detecting acoustic chest sounds. The IMD includes a pulse generator having a compartment, the compartment defining an isolated cavity bounded by a back wall. A diaphragm is disposed over and encloses the cavity. An acoustic sensor adapted to sense chest sounds and generate a signal is disposed between the diaphragm and the back wall. The IMD also includes a control circuit disposed within the pulse generator. The circuit is operatively coupled to the acoustic sensor and is adapted to receive the signal.

Abstract: The invention provides a method and apparatus for analysing a heart signal from a beating heart, the method comprising: collecting the heart signal, performing a cluster analysis of the signal to identify the first heart sound and the second heart sound, determining an energy envelope for each of a plurality of regions in the signal, determining the area of each of the energy envelopes, and classifying features in the signal by an analysis incorporating at least the areas, whereby one or more characteristics of the heart can be determined.

Abstract: A system for determining a patient's posture by monitoring heart sounds. The system comprises an implantable medical device that includes a sensor operable to produce an electrical signal representative of heart sounds, a sensor interface circuit coupled to the sensor to produce a heart sound signal, and a controller circuit coupled to the sensor interface circuit. The heart sounds are associated with mechanical activity of a patient's heart and the controller circuit is operable to detect a posture of the patient from a heart sound signal.

Abstract: A method for acquiring, externally or internally, for utility purposes a subject's anatomical heart-sound information including (a) for a selected time period, applying continuous, near-sensor-mechanical-resonance, vibratory stimulation to an acoustic sensor placed on or within the subject's anatomy, and (b) during that time period, detecting, as direct indications of heart sounds, changes in the sensor's physical resonance properties produced by heart sounds arriving at the sensor.

Abstract: A system and method for managing preload reserve and tracking the inotropic state of a patient's heart. The S1 heart sound is measured as a proxy for direct measurement of stroke volume. The S3 heart sound may be measured as a proxy for direct measurement of preload level. The S1-S3 pair yield a point on a Frank Starling type of curve, and reveal information regarding the patient's ventricular operating point and inotropic state. As an alternative, or in addition to, measurement of the S3 heart sound, the S4 heart sound may be measured or a direct pressure measurement may be made for the sake of determining the patient's preload level. The aforementioned measurements may be made by a cardiac rhythm management device, such as a pacemaker or implantable defibrillator.

Abstract: Sensing physiological conditions using the sensors of a respiratory therapy device can be used to assess a presence of pulmonary diseases other than breathing rhythm disorders. Non-rhythm related pulmonary diseases include, for example, obstructive pulmonary diseases, restrictive pulmonary diseases, and infectious diseases. Various pulmonary diseases will produce changes in respiratory pressure, airflow, and/or other patient conditions, facilitating assessment of a presence of disease.

Abstract: Methods, systems, and computer readable media are provided for identification of heart sound components in an audio signal of heart sounds. Time domain kurtosis and frequency domain kurtosis are used to distinguish peaks corresponding to the primary heart sounds, S1 and S2, from murmur peaks. Timing based error correction may also be used to verify that appropriate peaks corresponding to the primary heart sounds are identified.

Abstract: A system for determining a patient's posture by monitoring heart sounds. The system comprises an implantable medical device that includes a sensor operable to produce an electrical signal representative of heart sounds, a sensor interface circuit coupled to the sensor to produce a heart sound signal, and a controller circuit coupled to the sensor interface circuit. The heart sounds are associated with mechanical activity of a patient's heart and the controller circuit is operable to detect a posture of the patient from a heart sound signal.

Abstract: The disclosure describes an electronic stethoscope system that automatically detects coronary artery disease in patients. The system uses an electronic stethoscope to record acoustic data from the fourth left intercostal space of a patient. A processing technique is then applied in order to filter the data and produce Fast Fourier Transform (FFT) data of magnitude versus frequency. If a bell curve is identified in the data between a predefined frequency range (e.g., 50 and 80 Hz) with a peak magnitude of greater than a predefined threshold (e.g., 2.5 units), the system automatically provides an output indicating that the patient is likely to have 50 to 99 percent stenosis of the coronary artery. If no bell curve is present, the patient may have artery stenosis of less than 50 percent. An interface module may be used to transfer diagnosis information to the stethoscope and data to a general purpose computer.

Abstract: A system for monitoring heart and lung functions comprises an audio signal sensing unit, an audio signal processing unit, an electrocardiogram signal sensing unit, an electrocardiogram signal processing unit, and a microprocessor unit. The audio signal sensing unit senses audio signals, including a heart sound and a lung sound. The audio signal processing unit is connected to the audio signal sensing unit and processes the audio signals to obtain the heart sound and the lung sound. The electrocardiogram signal sensing unit senses an electrocardiogram signal. The electrocardiogram signal processing unit is connected to the electrocardiogram signal sensing unit and processes the electrocardiogram signal. The microprocessor unit is connected to the audio signal processing unit, the electrocardiogram signal processing unit and a computer host, and processes the heart sound, the lung sound and the electrocardiogram signal to be data that can be identified by the computer host.

Abstract: An implantable medical device such as a cardiac pacemaker or implantable cardioverter/defibrillator with the capability of receiving communications in the form of speech spoken by the patient. An acoustic transducer is incorporated within the device which along with associated filtering circuitry enables the voice communication to be used to affect the operation of the device or recorded for later playback.

Abstract: A system for fetal position-independent, non-invasive fetal monitoring includes a plurality of disposable adhesive patches for placement on an expectant mother's upper and lower abdomen. Each of the patches includes one or more miniature electronic devices embedded within the adhesive patches to detect: (i) heart sounds of a fetus within the mother, (ii) heart sounds of the mother, and (iii) signals indicative of uterine contractions of the mother. A processing hub having a receiver to receive signals from the plurality of patches, wherein the processing hub receives and processes primary signal from the primary patch and the secondary signals from the secondary patches to triangulate the location of the fetus, cancel noise in the primary signal and increase the amplitude of the primary signal for more reliable reporting.

Abstract: An apparatus for auscultation and percussion of a human or animal body has a stethoscope with a diaphragm on one side of a head thereof, and a percussion mechanism positioned in the head for selectively producing a percussion against the body such that a sound from the percussion mechanism is passed through a tube connected to the head. The percussion mechanism includes a cylinder positioned within the head, a piston slidably positioned within the cylinder, and an activator lever connected to the piston for moving the piston between a first position adjacent to an impact element and a second position away from the impact element.

Abstract: This document describes, among other things, a body having at least one acoustically detectable property that changes in response to a change in a physiological condition, such as ischemia. The body is positioned with respect to a desired tissue region. At least one acoustic transducer is used to acoustically detect a change in physical property. In one example, the body is pH sensitive and/or ion selective. A shape or dimension of the body changes in response to pH and/or ionic concentration changes resulting from a change in an ischemia state. An indication of the physiological condition is provided to a user.

Abstract: Generally, the present invention is directed to medical devices and more particularly to a patient-friendly stethoscope with interactive light emissions. An embodiment of the invention includes a stethoscope which has a pair of binaurals and a transparent acoustical tubing connecting the binaurals to the chestpiece. An optical fiber is located within the transparent acoustical tubing extending from the junction region of the tubing to and within the chestpiece, thereby illuminating the chestpiece, the rim of the diaphragm and bell, and attachments to the chestpiece. The optical fiber has a light source coupled at its proximal end thereby illuminating the transparent acoustical tubing, the chestpiece, and attachments thereto from within.

Abstract: Combining, to a singularity, from a plurality of anatomical sites, and over a plurality of heart cycles a collection of selected heart-functionality parameter measurements, such as EMAT, LVST, PADT, and AAFT measurements, including (a) collecting ECG and heart-sound data from plural anatomical sites, (b) computer processing such data to acquire plural, per-site, per-heart-cycle, nominal values for the selected parameter, (c) utilizing arithmetic mean and selected variance calculations related to such nominal values processing, and determined weight coefficients, computing weighted nominal values, (d) computing a weighted, nominal-value average of all of the nominal values by summing all of the weighted values and dividing that sum by the sum of all of the weight coefficients, and (e) presenting the computed weighted average as the combined, singularity value of the selected heart-functionality parameter.

Abstract: The disclosure describes an electronic stethoscope system that automatically detects coronary artery disease in patients. The system uses an electronic stethoscope to record acoustic data from the fourth left intercostal space of a patient. A processing technique is then applied in order to filter the data and produce Fast Fourier Transform (FFT) data of magnitude versus frequency. If a bell curve is identified in the data between a predefined frequency range (e.g., 50 and 80 Hz) with a peak magnitude of greater than a predefined threshold (e.g., 2.5 units), the system automatically provides an output indicating that the patient is likely to have 50 to 99 percent stenosis of the coronary artery. If no bell curve is present, the patient may have artery stenosis of less than 50 percent. An interface module may be used to transfer diagnosis information to the stethoscope and data to a general purpose computer.

Abstract: A method and device for automatically detecting heart valve damage for four heart valves are proposed. The automatic determination method makes use of three or more heart tone microphones to simultaneously record heart tones of a patient's heart, and then separates the heart tones into four heart tone signals of the aortic valve, the pulmonary valve, the tricuspid valve and the mitral valve of the heart based on the timing characteristics and related techniques. Next, these four heart tone signals are digitally processed into sampling signals. Subsequently, the convolution method is used to process the sampling signals for producing system transfer functions. Finally, the system transfer functions and the reference database are compared to verify and determine damage for the four heart valves. The automatic determination method can judge heart valve damage to enhance the quality and convenience of medical treatment.

Abstract: A method and system for analyzing sounds originating in at least a portion of an individual's cardiovascular system. N transducers, where N is an integer, are fixed on a surface of the individual over the thorax. The ith transducer is fixed at a location xi and generates an initial signal P(xi,i) indicative of pressure waves at the location xi, for i=1 to N. the signals P(xi,t) are processed so as to generate filtered signals in which at least one component of the signals P(xi,t)not arising from cardiovascular sounds has been removed. The filtered signals may be used for generating an image of the at least portion of the cardiovascular system.

Abstract: A dual-sensor stethoscope, or retrofit device for a stethoscope, promotes anti-sepsis and stereoscopy through use of a substantially rigid, generally T-shaped tube for support of dual stethoscope heads. Each head may be rotated away from a body independently for use of a single head or rotated into the same general plane for dual-head stereoscopy. A clinician can create a spatial, three-dimensional (3D) anti-septic barrier and avoid the need to carry multiple stethoscopes. During stereoscopy, the use of a common tube allows the transmission of sound with constructive interference of sound waves. The substantially rigid, generally T-shaped support tube allows a clinician to auscultate with one hand and monitor two locations without transference of pathogens.

Abstract: An apparatus for monitoring a patient's blood glucose level. The apparatus includes an implantable medical device having a controller and an implantable heart sounds sensor configured to transmit signals to the controller of the implantable medical device. The controller is configured to determine if a patient is hypoglycemic or hyperglycemic based on the signals from the heart sounds sensor. A method is also disclosed that includes sensing the patient's heart sounds, determining the amplitude of the S2 heart sound, determining the length of the interval from the S1 heart sound to the S2max heart sound, determining the length of the interval from the S1 heart sound to the S2end heart sound, and determining the patient's blood glucose status based on the patient's heart sounds.

Abstract: A heart sound analyzer component of an apparatus in one example extracts a heart sound of a fetus from heart sound information that comprises a plurality of mixtures of a plurality of heart sounds of a plurality of fetuses.

Abstract: An implantable medical device system senses a first signal using a first acoustical sensor adapted to be operatively positioned in a first internal body location for sensing heart sounds in a patient. The system includes a second acoustical sensor adapted to be operatively positioned in a second internal body location for sensing sounds in the patient and generate a second signal that is less responsive to the heart sounds than the first acoustical signal. An implantable medical device including a housing and a processor enclosed in the housing receives the first signal and the second signal and generates a corrected first signal by canceling non-cardiac signals in the first signal using the second signal.

Abstract: Article suitable for use as a medical device cover are disclosed. Methods of making and using the articles are also disclosed.

Abstract: A method and device for automatically detecting heart valve damage for four heart valves are proposed. The automatic determination method makes use of three or more heart tone microphones to simultaneously record heart tones of a patient's heart, and then separates the heart tones into four heart tone signals of the aortic valve, the pulmonary valve, the tricuspid valve and the mitral valve of the heart based on the timing characteristics and related techniques. Next, these four heart tone signals are digitally processed into sampling signals. Subsequently, the convolution method is used to process the sampling signals for producing system transfer functions. Finally, the system transfer functions and the reference database are compared to verify and determine damage for the four heart valves. The automatic determination method can judge heart valve damage to enhance the quality and convenience of medical treatment.

Abstract: This document describes, among other things, a body having at least one acoustically detectable property that changes in response to a change in a physiological condition, such as ischemia. The body is positioned with respect to a desired tissue region. At least one acoustic transducer is used to acoustically detect a change in physical property. In one example, the body is pH sensitive and/or ion selective. A shape or dimension of the body changes in response to pH and/or ionic concentration changes resulting from a change in an ischemia state. An indication of the physiological condition is provided to a user.

Abstract: A cardiac rhythm management system includes a heart sound detector providing for detection of the third heart sounds (S3). An implantable sensor such as an accelerometer or a microphone senses an acoustic signal indicative heart sounds including the second heart sounds (S2) and S3. The heart sound detector detects occurrences of S2 and starts S3 detection windows each after a predetermined delay after a detected occurrence of S2. The occurrences of S3 are then detected from the acoustic signal within the S3 detection windows.

Abstract: An auscultation system aids a clinician's diagnosis of the heart sounds by visually displaying at least an S1 heart sound and an S2 heart sound, and ascertaining an onset of at least one of the heart sounds. A corresponding audio representation of the heart sounds can be provided to the clinician. The auscultation system includes a sensor for sensing heart sounds from at least one chest location of the patient and for transducing the heart sounds into electrical signals. The auscultation system also includes a signal processor for selectively filtering the electrical signals thereby highlighting frequency differences of the heart sounds, and further includes a video display for selectively displaying the selectively filtered electrical heart signals.

Abstract: A method and system for modeling cardiovascular disease using a probability regression model is provided. A parameter estimate of a probability regression model for cardiovascular disease can be generated using predictors derived from cardiovascular sound signals and disease status information. A probability of cardiovascular disease can be generated using a probability regression model that includes a predictor derived from cardiovascular sound signals.

Abstract: A procedure for extracting features from phonocardiographic signals without the use of synchronizing information from electrocardiographic signals. The features extracted are the timing and value of first and second heart sounds and various combinations of timing and value of signal components constituting heart murmur. Such combinations are directly related to various heart conditions, which are more easily diagnosable by a medically trained person when assisted by the signal extraction. The features are extracted by a novel combination of energy/time relationships for the heart signal and various novel classification schemes.

Abstract: A quasi-periodic signal with high signal-to-noise ratio containing signal features that exhibit poor temporal localization is processed to identify waveform temporal reference points that are used to provide the temporal reference points for extracting a representative waveform of a signal feature having high temporal localization in a second, related, quasi-periodic signal that has low signal-to-noise ratio. The resulting representative waveform exhibits much improved signal-to-noise ratio while preserving the temporal detail contained in the second, related, quasi-periodic signal.

Abstract: A tunable auscultation system includes a heart sound acquirer for sensing heart sounds from at least one chest location of the patient. An initial conditioner then conditions the heart sounds through pre-amplification and anti-aliasing. The heart sounds are transduced into electrical signals by a signal processor. The electric heart signals are then tuned by an analysis tool. The analysis tool includes an interaction tuner, a processing tuner and an output tuner. The interaction tuner includes a preset tuning selector and a dynamic range tuning selector. The processing tuner includes a band pass filter and an algorithmic extraction engine which applies extraction algorithms to the electric heart signals, segments them and extracts signals of interest. Signals of interest may be correlated to specific pathologies. The output tuner includes a signal strength indicator, a diagnosis indicator, an overlapping cardiac cycle display and a display configuration engine. A display module provides output.

Abstract: A medical stethoscope head (1) comprises a body (2) with an inlet pipe and at least one diaphragm portion (4) provided with a diaphragm (5) at its lower surface. At least one identifying-personalizing ring (11) provided with identifying-personalizing means (14) is mounted in any area of an upper surface (10) of said diaphragm portion (4), opposite to said diaphragm (5). The identifying-personalizing ring (11), at its surface adjacent to the diaphragm portion (4), is provided with at least one locating element for explicit locating the identifying-personalizing ring (11) in defined angular position in relation to an axis (3?) of said inlet pipe (3) of said body (2).

Abstract: A system and method provide heart sound tracking, including an input circuit, configured to receive heart sound information, and a heart sound recognition circuit. The heart sound recognition circuit can be coupled to the input circuit and can be configured to recognize, within a particular heart sound of a particular heart sound waveform, a first intra heart sound energy indication and a corresponding first intra heart sound time indication using the heart sound information from the particular heart sound waveform and the heart sound information from at least one other heart sound waveform. The particular heart sound can include at least a portion of one of S1, S2, S3, and S4. Further, the first intra heart sound energy indication and the corresponding first intra heart sound time indication can correspond to the at least a portion of one of S1, S2, S3, and S4, respectively.

Abstract: A heart signal comprising both first and second heart sounds and murmurs occurring due to various heart conditions is modeled by a sum of sinusoids automatically selected to represent the heart sound without a noise component. In an analysis step the signal parameters are measured, in an interpolation and transformation part ?(t) and A(t) are interpolated from one window position to the next window position, and a synthesis part reconstructs the transformed heart signal. The transformations are transformations in either time scale (with unchanged frequency content) or frequency scale (with unchanged time progression), or both. Furthermore a dynamic transformation of an arbitrary heart signal to a fixed number of beats per minute is made possible.

Abstract: A heart sound analyzer component of an apparatus in one example extracts a heart sound of a fetus from heart sound information that comprises a plurality of mixtures of a plurality of heart sounds of a plurality of fetuses.

Abstract: A cardiac rhythm management system includes a heart sound detector providing for detection of the third heart sounds (S3). An implantable sensor such as an accelerometer or a microphone senses an acoustic signal indicative heart sounds including the second heart sounds (S2) and S3. The heart sound detector detects occurrences of S2 and starts S3 detection windows each after a predetermined delay after a detected occurrence of S2. The occurrences of S3 are then detected from the acoustic signal within the S3 detection windows.

Abstract: A multi-functional, hand-held medical device for measuring bodily functions and physiological parameters and for medical screening and diagnosis by dual sound detection. A multi-functional, hand-held medical device capable of accurate, automatic and instantaneous readings of data received from the patient's different bodily functions, enhances productivity of the user, allows for flexibility to adjust the distance between the patient and the user, and reduces the potential for transmission of infectious or contagious organisms between the patient and the user. A multi-functional, hand-held medical device that does not require the use of earpieces. A method for measuring bodily functions and physiological parameters and for medical screening and diagnosis by dual sound detection.

Abstract: A system to monitor heart sounds, such as to detect a worsening condition of heart failure decompensation. The system comprises a medical device that includes an implantable multi-axis heart sound sensor, operable to produce, for each of at least two nonparallel axes, an electrical signal representative of at least one heart sound, the heart sound associated with mechanical activity of a patient's heart. The device further includes a controller circuit coupled to the heart sound sensor. The controller circuit measures components of the heart sound that respectively correspond to each of the axes.

Abstract: A system and method for detecting and processing physiological sounds. The method includes sensing physiological sounds to acquire analog physiological signals, where the acquired analog physiological signals corresponding to basic heart sounds and sounds of interest. A predetermined frequency range of the acquired analog physiological signals that encompasses the sounds of interest are amplified, where at least a portion of the predetermined frequency range is higher than another frequency range of the acquired analog physiological signals that encompasses the basic heart sounds.

Abstract: Described is an implantable device configured to monitor for changes in the intensity and/or duration of a systolic murmur such as mitral regurgitation by means of an acoustic sensor. Such changes may be taken to indicate a change in a patient's heart failure status. Upon detection of a worsening in the patient's heart failure statue, the device may be programmed to alert clinical personnel over a patient management network and/or make appropriate adjustments to pacing therapy.

Abstract: A system comprising a heart sound sensor to produce a heart sound signal representative of at least one heart sound. A signal analyzer circuit measures a baseline time interval between a first detected physiologic cardiovascular event and at least one second detected physiologic cardiovascular event. At least one of the first and second detected physiologic cardiovascular events includes a heart sound event obtained from the heart sound signal. The sensor analyzer circuit determines that an ischemic event occurred at least in part by detecting a specified measured subsequent change from the established baseline time interval. Other systems and methods are disclosed.

Abstract: A method and system of cardiac contractility analysis is provided. Cardiac contractility may include indices such as ejection fraction (EF) and rate of change in pressure (dP/dt) in a heart. Heart sounds may be measured and calibrated by attenuation. Likewise, a first acoustic peak in the first heart sound (S1), and a second acoustic peak of the second heart sound (S2) may be identified. The first heart sound (S1) may be calibrated by the second heart sound (S2). Amplitudes of calibrated heart sounds may be correlated to cardiac contractility. Electrical activity and acoustics of the heart are measured. The pre-ejection period of the cardiac cycle may be calculated. The left ventricular ejection time of the cardiac cycle may likewise be calculated. Then a ratio of pre-ejection period over left ventricular ejection time may be calculated and correlated to cardiac contractility. Pressure on the acoustic sensor may be used to calibrate acoustic data.

Abstract: This document discusses, among other things, a system comprising an implantable medical device (IMD) including an implantable heart sound sensor circuit configured to produce an electrical heart sound signal representative of a heart sound of a subject and a processor circuit. The processor circuit is coupled to the heart sound sensor circuit and includes a detection circuit, a heart sound feature circuit and a trending circuit. The detection circuit configured to detect a physiologic perturbation and the heart sound feature circuit is configured to identify a heart sound feature in the electrical signal. The processor circuit is configured to trigger the heart sound feature circuit in relation to a detected physiologic perturbation. The trending circuit is configured to trend the heart sound feature in relation to a recurrence of the physiologic perturbation. The processor circuit is configured to declare a change in a physiologic condition of the patient according to the trending.

Abstract: Respiration-synchronized heart sound trends can be detected using an implantable medical device, including a respiration sensor, a respiration phase detector, a heart sound sensor, a heart sound detector, and a processor. The implantable medical device can also include a cardiac sensor. The respiration-synchronized heart sound trends can include heart sounds occurring during specific phases of a respiration signal, such as inspiration or expiration. The heart sound signal can be gated or the heart sound sensor can be enabled or disabled using the cardiac sensor or the respiration sensor. Further, the heart sound trends can be displayed using an external display, and can provide information about a cardiovascular status using an analysis module, or the analysis module and a blood volume sensor.

Abstract: An external heart sound sensor externally detects at least one heart sound from a patient, which information is used to automatically adjust one or more cardiac resynchronization therapy (CRT) or other control parameters of an implantable medical device, such as an implantable cardiac rhythm management device. An external telemetry circuit is coupled to the external heart sound sensor, and the telemetry circuit receives information about the at least one heart sound. The external telemetry circuit is also adapted to communicate with an implantable medical device for automatically programming at least one parameter of the implantable medical device using information about the at least one heart sound received from the external heart sound sensor.

Abstract: A heart sound analyzer component of an apparatus in one example extracts from composite heart sound information one or more discrete heart sounds of one or more corresponding distinct heart sound sources.