Abstract: Methodology involving assessing, and applying therapy regarding, degree of ischemia and risk for sudden cardiac death in a therapy-device-equipped subject utilizing a Holter-type instrumentality. The methodology includes (a) gathering simultaneous ECG and heart-sound data, (b) computer processing and interrelating the gathered data to obtain one or more heart-functionality parameter(s), focusing on LDPT and % LVST, and (c), using these obtained parameters, adjusting, as necessary, the therapy device so as to minimize and counteract the likelihood of the onset or advancement of ischemia, and/or the onset of sudden cardiac death.

Abstract: A medical system according to embodiments of the present invention includes at least one sensor configured to monitor physiological status of a patient and to generate sensor data based on the physiological status, a user interface device, a processor communicably coupled to the user interface device, the processor configured to: present via the user interface device an array of two or more possible input elements, the input elements each comprising a class of patients or a diagnosis and treatment pathway; receive a selected input element based on a user selection among the two or more possible input elements; acquire the sensor data and process the sensor data to generate physiological data; and present via the user interface screen the physiological data according to a template that is customized for the selected input element.

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: An apparatus for outputting heart sounds includes an implantable system and an external system. The implantable system includes a sensor for generating sensed signals representing detected heart sounds, an interface circuit and a control circuit for receiving the sensed signals, generating data representing the heart sounds therefrom, and transmitting the data to the external system via the interface circuit. The external system includes an interface circuit for communicating with the implantable system, and a control circuit for receiving the data representing the heart sounds and for generating control signals that cause an output device to generate outputs representing the sounds. The implantable system may also include a sensor(s) for detecting cardiac electrical signals. In this case, outputs representing the cardiac electrical signals are also output.

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 and method to sense heart sounds with one or more implantable medical devices according to one or more signal processing parameters. The method alters one or more of the parameters as a function of one or more physiologic triggering events. The method then senses heart sounds with the one or more implantable medical devices according to at least the one or more altered signal processing parameters.

Abstract: A wavelet transform and pattern recognition method for analyzing a subject's heart sounds including (a) obtaining subject-related heart-sound data utilizing a first sampling rate, (b) obtaining simultaneously existing subject ECG data, including pre-selected ECG fiducial data, and (c) processing such obtained data including, relative to the heart-sound data, (1) computing the maximum-overlap discrete wavelet transform (MODWT) for a preselected number of wavelet scales, (2) locating the peaks in time of the absolute values of the MODWT coefficients respecting each of a such scales, and (3), for each such scale, (i) interpolating between the located peaks, and (ii) subsampling each interpolation result at a second sampling rate which no greater than the mentioned first sampling rate.

Abstract: The present invention exploits a visual rendering of heart sounds and models the morphological variations of audio envelopes through a constrained non-rigid translation transform. Similar heart sounds are then retrieved by recovering the corresponding alignment transform using a variant of shape-based dynamic time warping.

Abstract: A method for detecting a condition of a heart of a patient using an implantable medical device, including the steps of sensing acoustic signals indicative of heart sounds of the heart of the patient; extracting signals corresponding to a first heart sound (S1) and a second heart sound (S2) from sensed signals; calculating an energy value corresponding to a signal corresponding to the first heart sound (S1) and an energy value corresponding to the second heart sound (S2); calculating a relation between the energy value corresponding to the first heart sound and the energy value corresponding to the second heart sound for successive cardiac cycles; and using at least one relation to detect the condition or a change of the condition. A medical device for determining the posture of a patient and a computer readable medium encoded with instructions are used to perform the inventive method.

Abstract: Systems according to the invention employ an acceleration sensor to characterize displacement and vibrational LV motion, and uses this motion data to characterize the different phases of the LV cycle for analyzing LV function. Systems may identify a target pacing region or regions in the LV or RV using the acceleration sensor by localizing regions of late onset of motion relative to the QRS, or isovolumic contraction, or mitral valve closure, or by pacing of target regions and measuring LV function in response to pacing. Systems further provide an implantable or non-implantable acceleration sensor device for measuring LV motion and characterizing LV function. An implantable myocardial acceleration sensing system (“IAD”) includes at least one acceleration sensor, a data acquisition and processing device, and an electromagnetic, e.g., RF, communication device. The IAD may be integrated into the pacing lead of a CRT device and can operate independently of the CRT IPG.

Abstract: A cardiac rhythm management system provides for ambulatory monitoring of hemodynamic performance based on quantitative measurements of heart sound related parameters for diagnostic and therapeutic purposes. Monitoring of such heart sound related parameters allows the cardiac rhythm management system to determine a need for delivering a therapy and/or therapy parameter adjustments based on conditions of a heart. This monitoring also allows a physician to observe or assess the hemodynamic performance for diagnosing and making therapeutic decisions. Because the conditions of the heart may fluctuate and may deteriorate significantly between physician visits, the ambulatory monitoring, performed on a continuous or periodic basis, ensures a prompt response by the cardiac rhythm management system that may save a life, prevent hospitalization, or prevent further deterioration of the heart.

Abstract: Cardiac monitoring and stimulation methods and systems provide audio playback of cardiac events and transthoracic monitoring and therapy. A medical system includes a housing and electrodes configured for sensing cardiac electrical activity. Another sensor may be configured to sense heart movement and produce a signal in response, such as an audio signal. Memory stores the audio signal and the cardiac electrical signal. A controller and communications circuitry telemeter the cardiac electrical signal and the audio signal to a patient-external device. Energy delivery circuitry may deliver cardiac therapy. The device may further include a patient actuatable trigger configured to communicate to the controller via the communications circuitry. The controller may initiate storing of the cardiac electrical signal and the audio signal in response to the trigger. The patient-external device may further include a storage media.

Abstract: A cable monitoring apparatus includes a housing having an input interface adapted to electrically connect to one end of a medical cable and an output interface adapted to electrically connect to a medical monitoring apparatus. Signal processing circuitry is incorporated within the housing for receiving a medical signal from the medical cable via the input interface and for selectively passing the medical signal to the medical monitoring apparatus via the output interface when in a first mode of operation, and has application software for selectively testing functionality of the medical cable when in a second mode of operation.

Abstract: Aspects of the of the disclosure relate to a non-contact physiological motion sensor and a monitor device that can incorporate use of the Doppler effect. A continuous wave of electromagnetic radiation can be transmitted toward one or more subjects and the Doppler-shifted received signals can be digitized and/or processed subsequently to extract information related to the cardiopulmonary motion in the one or more subjects. The extracted information can be used, for example, to determine apneic events and/or to provide apnea therapy to subjects when used in conjunction with an apnea therapy device. In addition, methods of use are disclosed for sway cancellation, realization of cessation of breath, integration with multi-parameter patient monitoring systems, providing positive providing patient identification, or any combination thereof.

Abstract: A method and system of supplying rodents, such as mice, to medical researchers pre-installs and/or embeds physiologic sensors onto or within the rodents prior to selling the modified rodents to the researchers. The specialty skills, such as small animal surgical and anesthesia skills and sensor placement and testing, are centralized in one organization rather than being spread about a collection of researchers. The subjects with preinstalled, pre-tested hardware, are sold to the researcher as needed. Communication hardware and software will be supplied for the user to convert their desktop computer into a wireless monitoring station. Additionally an external pulse oximeter for small rodents, such as mice, provides measurements on a hand or foot of the rodent with a sensor configured to avoid shunting around the rodent appendage, and configured for high heart rates (200-900 beats per minutes) of the subjects.

Abstract: A system and method to sense heart sounds with one or more implantable medical devices according to one or more parameters. The system alters one or more of the parameters as a function of one or more triggering events. The system then senses heart sounds with the one or more implantable medical devices according to at least the one or more altered parameters.

Abstract: An enclosure for a medical instrument including a pair of flexible sheets transmissive to a signal generated by a subject, the pair of sheets being arranged in parallel to each other, sealed along the sides and the top, and between the opposing lateral sides and the top and bottom ends along one or more seam lines.

Abstract: An embodiment of an auscultation device can be constructed using electronic components to provide improved acquisition, processing, and communication of sound signals. An input device can be used for detecting sounds, and electrical signals representing the sounds can be processed and transmitted via Bluetooth and/or another form of wireless communication. Such embodiments can employ, at least in part, one or more of several commercially available wireless receiver devices, such as, without limitation, headsets and headphones, mobile phones, PDAs and/or other handheld devices, desktop, laptop, palmtop, and/or tablet computers and/or other computer devices and/or electronic devices.

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: Systems and methods to monitor cardiac mechanical vibrations using information indicative of lead motion are described. In an example, a system including an implantable medical device can include an excitation circuit configured to provide a non-tissue stimulating, non-therapeutic electrical excitation signal to a portion of an implantable lead. A receiver circuit can be configured to obtain information indicative of a mechanical vibration of the implantable lead due at least in part to one or more of an impact of at least a portion of the heart to the implantable lead, or friction contact between the implantable lead and cardiac tissue. The system can include a processor circuit configured to determine one or more of a lead mechanical status, or information indicative of valvular activity using the information indicative of the mechanical vibration of the implantable lead.

Abstract: A system and method for assessing cardiac performance through cardiac vibration monitoring is described. Cardiac vibration measures are directly collected through an implantable medical device. Cardiac events including at least one first heart sound reflected by the cardiac vibration measures are identified. The first heart sound is correlated to cardiac dimensional measures relative to performance of an intrathoracic pressure maneuver. The cardiac dimensional measures are grouped into at least one measures set corresponding to a temporal phase of the intrathoracic pressure maneuver. The at least one cardiac dimensional measures set is evaluated against a cardiac dimensional trend for the corresponding intrathoracic pressure maneuver temporal phase to represent cardiac performance.

Abstract: Apparatus and methods for vibro-acoustic detection of cardiac conditions are disclosed. An example method includes calculating a frequency difference between a first frequency of a first cardiac signal and a second frequency of a second cardiac signal; calculating an amplitude difference between the first cardiac signal and the second cardiac signal; calculating a root-mean-square value based on a difference between the first cardiac signal and the second cardiac signal; calculating a value based on the frequency difference, the amplitude difference, and the root-mean-square value; and detecting a cardiac condition based on the value.

Abstract: A method for gathering, creating and utilizing signal-processed ECG and acoustic signals for assessing, via presenting a highly intuitive, multi-component, common-time-base, real-time output display of selected (1) timing, (2) relative timing, and (3) other significant heart-behavioral elements relevant to such an assessment, a pacemaker patient's hemodynamic condition. The method offers an important option and capability for automatic, and/or manual, medical-treatment and/or pacemaker-control feedback, in real time, to improve a pacemaker patient's hemodynamic status, with such a patient's resulting hemodynamic-behavioral/status changes caused by such feedback being viewable immediately in the invention's produced output display.

Abstract: A cardiac rhythm management system provides for ambulatory monitoring of hemodynamic performance based on quantitative measurements of heart sound related parameters for diagnostic and therapeutic purposes. Monitoring of such heart sound related parameters allows the cardiac rhythm management system to determine a need for delivering a therapy and/or therapy parameter adjustments based on conditions of a heart. This monitoring also allows a physician to observe or assess the hemodynamic performance for diagnosing and making therapeutic decisions. Because the conditions of the heart may fluctuate and may deteriorate significantly between physician visits, the ambulatory monitoring, performed on a continuous or periodic basis, ensures a prompt response by the cardiac rhythm management system that may save a life, prevent hospitalization, or prevent further deterioration of the heart.

Abstract: An implantable device and method for monitoring S1 heart sounds with a remotely located accelerometer. The device includes a transducer that converts heart sounds into an electrical signal. A control circuit is coupled to the transducer. The control circuit is configured to receive the electrical signal, identify an S1 heart sound, and to convert the S1 heart sound into electrical information. The control circuit also generates morphological data from the electrical information. The morphological data relates to a hemodynamic metric, such as left ventricular contractility. A housing may enclose the control circuit. The housing defines a volume coextensive with an outer surface of the housing. The transducer is in or on the volume defined by the housing.

Abstract: The invention provides a method of processing at least one heart sound signal, and the method comprises the step of: receiving (11) the at least one heart sound signal, segmenting (12) the heart sound signal into a plurality of segments, identifying (13) attribute information for each segment, annotating (14) each segment with corresponding attribute information, and outputting (15) an annotated Phonocardiogram for the at least one heart sound signal. The invention also provides a processing system for implementing the step of the methods as mentioned above.

Abstract: An acoustic-electronic stethoscope that filters aberrant environmental background noise. The chest piece employs acoustic vents to inhibit resonant amplification of noise and contains a diaphragm design that focuses vibrational energy to a raised ring, which transfers and further focuses the energy to a piezoelectric polymer sensor with dual elements. The ensuing electrical signal is then preamplified with the low frequency sound, comprising predominantly background noise, filtered out. The stethoscope contains a binaural head set and output jack for down loading of data. Furthermore, areas normally subject to exposure and damage to water, such as the chest piece and headset, are water-tight.

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: A neural stimulation system senses autonomic activities and applies neural stimulation to sympathetic and parasympathetic nerves to control autonomic balance. The neural stimulation system is capable of delivering neural stimulation pulses for sympathetic excitation, sympathetic inhibition, parasympathetic excitation, and parasympathetic inhibition.

Abstract: A system and method for assessing cardiac performance through cardiac vibration monitoring is described. Cardiac vibration measures are directly collected through an implantable medical device. Cardiac events including at least one first heart sound reflected by the cardiac vibration measures are identified. The first heart sound is correlated to cardiac dimensional measures relative to performance of an intrathoracic pressure maneuver. The cardiac dimensional measures are grouped into at least one measures set corresponding to a temporal phase of the intrathoracic pressure maneuver. The at least one cardiac dimensional measures set is evaluated against a cardiac dimensional trend for the corresponding intrathoracic pressure maneuver temporal phase to represent cardiac performance.

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 determining a heartbeat rate of a user from an acoustic heartbeat signal, a heartbeat rate measuring device, and a mobile device are described.

Abstract: An implantable device and method for monitoring S1 heart sounds with a remotely located accelerometer. The device includes a transducer that converts heart sounds into an electrical signal. A control circuit is coupled to the transducer. The control circuit is configured to receive the electrical signal, identify an S1 heart sound, and to convert the S1 heart sound into electrical information. The control circuit also generates morphological data from the electrical information. The morphological data relates to a hemodynamic metric, such as left ventricular contractility. A housing may enclose the control circuit. The housing defines a volume coextensive with an outer surface of the housing. The transducer is in or on the volume defined by the housing.

Abstract: Methods and systems for mapping a physiological signal into clinical guideline parameters are disclosed. A physiological signal having a characteristic that may represent an anomaly is received and mapped to a clinical guideline condition space. Probabilities are determined that the mapped signal with which the anomaly may be associated represents a first clinical guideline condition corresponding to a referral indication or a second clinical guideline condition corresponding to an absence of the referral indication. The determined probability is presented and a referral decision is made responsive to the determined probability that the anomaly is associated with the first clinical guideline condition.

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 stethoscope cover and carrier strip assembly and a respective stethoscope diaphragm cover dispensing apparatus. The stethoscope cover and carrier strip assembly comprises a plurality of stethoscope covers detachably coupled to a carrier strip in a linear, spatial arrangement. Each cover is fabricated of a thin, elastically deformable membrane-like central portion defined by a peripheral edge. The covers are sized and shaped for placement over stethoscope diaphragm or a complete stethoscope head. The dispenser advances a cover into a staging area, where the cover is stretched in both a longitudinal and a lateral direction to allow unencumbered insertion of the stethoscope diaphragm or a complete stethoscope head. The cover is removed from the carrier and the spent carrier material is collected for disposition.

Abstract: Systems and methods are provided for graphically configuring leads for a medical device. According to one aspect, the system generally comprises a medical device and a processing device, such as a programmer or computer, adapted to be in communication with the medical device. The medical device has at least one lead with at least one electrode in a configuration that can be changed using the processing device. The processing device provides a graphical display of the configuration, including a representative image of a proposed electrical signal to be applied by the medical device between the at least one electrode of the medical device and at least one other electrode before the medical device applies the electrical signal between the at least one electrode and the at least one other electrode. In one embodiment, the graphical display graphically represents the lead(s), the electrode(s), a pulse polarity, and a vector.

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 monitoring physiological parameters is useful for remote auscultation of the heart and lungs. The system includes an acoustic sensor (105) that has a stethoscopic cup (305). A membrane (325) is positioned adjacent to a first end of the stethoscopic cup (305), and an impedance matching element (335) is positioned adjacent to the membrane (325). The element (335) provides for acoustic impedance matching with a body such as a human torso. A microphone (315) is positioned near the other end of the stethoscopic cup (305) so as to detect sounds from the body. A signal-conditioning module (110) is then operatively connected to the acoustic sensor (105), and a wireless transceiver (115) is operatively connected to the signal-conditioning module (110). Auscultation can then occur at a remote facility that receives signals sent from the transceiver (115).

Abstract: A cardiac rhythm management system provides for ambulatory monitoring of hemodynamic performance based on quantitative measurements of heart sound related parameters for diagnostic and therapeutic purposes. Monitoring of such heart sound related parameters allows the cardiac rhythm management system to determine a need for delivering a therapy and/or therapy parameter adjustments based on conditions of a heart. This monitoring also allows a physician to observe or assess the hemodynamic performance for diagnosing and making therapeutic decisions. Because the conditions of the heart may fluctuate and may deteriorate significantly between physician visits, the ambulatory monitoring, performed on a continuous or periodic basis, ensures a prompt response by the cardiac rhythm management system that may save a life, prevent hospitalization, or prevent further deterioration of the heart.

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: 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 to monitor heart sounds. The system comprises an implantable heart sound sensor configured to produce an electrical signal representative of at least one heart sound, an implantable posture sensor operable to produce an electrical signal representative of a patient's posture, and a controller circuit. The controller circuit is configured to determine a patient posture, measure at least one heart sound in correspondence with at least one corresponding patient posture, adjust the heart sound measurement by using the corresponding determined patient posture to reduce or remove variation in the heart sound measurement due to patient posture, detect a change in the adjusted heart sound measurement, and provide an indication of congestive heart failure to a user or an automated process in response to the detected change.

Abstract: A method and apparatus are disclosed for treating mitral regurgitation with electrical stimulation. By providing pacing stimulation to the left atrium during ventricular systole, a beneficial effect is obtained which can prevent or reduce the extent of mitral regurgitation.

Abstract: A method and system for processing of physiological signals is provided. The system processes information signals in subband-domain associated with the physiological signals in time-domain. The information signals are obtained by one or more over-sampled filterbanks. The method and system possibly synthesizes the subband signals obtained by subband processing. The method and system may implement the analysis, subband processing, and synthesis algorithms on over-sampled filterbanks, which are implemented on ultra low-power, small size, and low-cost platform in real-time. The method and system may use over-sampled, Weighted-Overlap Add (WOLA) filterbanks.

Abstract: A method for personalizing a stethoscope, wherein the personalization permanently identifies the owner of the stethoscope and also decorates the stethoscope. The personalization does not deter from the normal operation of the stethoscope, and allows for full sterilization of the stethoscope. The diaphragm of the stethoscope, includes an exterior side that is adapted to come into contact with the patient and, an interior side that is not exposed to the outside. A design selected by the owner is applied, in reverse, to the interior surface of the diaphragm. The design is preferably painted on the diaphragm in stages, or layers. Using the present reverse application technique, images painted on the right-half of the interior surface, appear on the left-half, when viewed from the exterior of the stethoscope. Further, in the present application technique, the foreground is painted on, or applied, first, and the background of the personalization is applied last.

Abstract: Embodiments of the invention include a system and methods for providing status information about resuscitation efforts of a person receiving chest compressions as part of Cardiopulmonary Resuscitation (CPR). A microphone generates a soundtrack by sampling sounds within or around the body of the person receiving CPR. The soundtrack is gated in one or more various ways to eliminate portions of the soundtrack, and analysis performed on the remaining portions. By evaluating the remaining portions of the soundtrack, the system can determine a cardiovascular effect of the compressions and provide status information to the rescuer about the determined cardiovascular effect.

Abstract: An apparatus for outputting heart sounds includes an implantable system and an external system. The implantable system includes a sensor for generating sensed signals representing detected heart sounds, an interface circuit and a control circuit for receiving the sensed signals, generating data representing the heart sounds therefrom, and transmitting the data to the external system via the interface circuit. The external system includes an interface circuit for communicating with the implantable system, and a control circuit for receiving the data representing the heart sounds and for generating control signals that cause an output device to generate outputs representing the sounds. The implantable system may also include a sensor(s) for detecting cardiac electrical signals. In this case, outputs representing the cardiac electrical signals are also output.

Abstract: A vector method for monitoring a subject's hemodynamic condition including (a) utilizing at least one, external or internal, anatomy-attached, three-axis accelerometer, collecting from the subject, during a selected cardiac cycle, related, three-orthogonal-axes accelerometer signal data, (b) following such collecting, processing collected signal data to obtain associated, signal vector, magnitude and directionality information, and (c) analyzing such obtained vector information for assessment of the subject's heart hemodynamic condition. ECG and signal time-frequency data is also collected and used in certain manners and implementations of the invention.

Abstract: A cardiac rhythm management system provides for ambulatory monitoring of hemodynamic performance based on quantitative measurements of heart sound related parameters for diagnostic and therapeutic purposes. Monitoring of such heart sound related parameters allows the cardiac rhythm management system to determine a need for delivering a therapy and/or therapy parameter adjustments based on conditions of a heart. This monitoring also allows a physician to observe or assess the hemodynamic performance for diagnosing and making therapeutic decisions. Because the conditions of the heart may fluctuate and may deteriorate significantly between physician visits, the ambulatory monitoring, performed on a continuous or periodic basis, ensures a prompt response by the cardiac rhythm management system that may save a life, prevent hospitalization, or prevent further deterioration of the heart.