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 method and device for detecting cardiac signals that includes a first plurality of electrodes that senses cardiac signals and delivers therapy, and a second plurality of electrodes that senses the cardiac signals. A microprocessor detects a cardiac event in response to the sensing by the first plurality of electrodes, and verifies the cardiac event in response to the sensing by the second plurality of electrodes.

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 system for diagnosing Long QT Syndrome (LQTS) derives a QT/QS2 ratio from an electrical systole (QT) and a mechanical systole (QS2) to detect a prolonged QT interval in a patient's cardiac cycle. A processor acquires the systoles from a microphone and chest electrodes, calculates the QT/QS2 ratio, and outputs the result to a display. The processor may compare the QT/QS2 ratio to a threshold value stored in memory for diagnosing LQTS in the patient. A user interface provides for programming, set-up, and customizing the display. A mode selector allows the system to operate alternatively as a phonocardiograph, a 12 lead electrocardiograph, or a machine for diagnosing LQTS. A related method for diagnosing cardiac disorders such as LQTS includes measuring QT and QS2 during a same cardiac cycle, calculating a QT/QS2 ratio, and comparing the result to a threshold value derived from empirical data.

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: Apparatus for measuring a user's heart rate and other physiological parameters derived from two electrodes at least one of which is in contact with the user's head. The second electrode is in contact with the user's skin. A heart rate detection circuit is coupled to the electrodes to detect the user's heart rate as electrical potential difference between the first and second electrodes. The electrodes may be integral with user apparel such as hats, headbands, helmets, eyewear, etc. The electrodes may be integral with headphone speakers in contact with the user's ears. The heart rate detection circuit may be integral with or coupled to an audio source device such as an MP3 player or a portable communication device. The detected heart rate may be presented to the user as audio signals or as visually displayed information. A third electrode may be added to improve the quality of the sensed signals.

Abstract: Apparatus and associated methodology for monitoring correlatable anatomical electrical and sound signals, such as electrical and audio signals produced by human heart activity, including (a) attaching to a selected, common anatomical site ECG (or other) electrode structure, and a multi-axial sound sensor, and (b) simultaneously collecting from adjacent that site both ECG(or other)-electrical and sound signals, where such sound signals arrive adjacent the site along multiple, angularly intersecting axes.

Abstract: A cardiac rhythm management system provides a phonocardiographic image indicative of a heart's mechanical events related to hemodynamic performance. The phonocardiographic image includes a stack of acoustic sensor signal segments representing multiple cardiac cycles. Each acoustic sensor signal segment includes heart sounds indicative of the heart's mechanical events and representations of the heart's electrical events. The stack of acoustic sensor signal segments are aligned by a selected type of the heart's mechanical or electrical events and are grouped by a cardiac timing parameter for presentation.

Abstract: An implantable medical device includes a dual-use sensor such as a single accelerometer that senses an acceleration signal. A sensor processing circuit processes the acceleration signal to produce an activity level signal and a heart sound signal. The implantable medical device provides for rate responsive pacing in which at least one pacing parameter, such as the pacing interval, is dynamically adjusted based on the physical activity level. The implantable medical device also uses the heart sounds for pacing control purposes or transmits a heart sound signal to an external system for pacing control and/or diagnostic purposes.

Abstract: A system, method, and computer executable code for generating a likelihood of cardiovascular disease from acquired cardiovascular sound signals is diesclosed, where the generated likelihood of cardiovascular disease is based at least on an overlapping in time of bruit candidates in one heart cycle or in different heart cycles. Also disclosed is a system, method, and computer executable code for collecting, forwarding, and analyzing cardiovascular sound signals, where the collecting and analyzing may occur at locations that are remote from each other. Further disclosed is a system, method, and computer executable code for determining the time and phase information contained in cardiovascular sound signals, for use in analyzing those cardiovascular sound signals.

Abstract: A cardiac rhythm management system measures a time interval between a first fiducial marker indicative of a ventricular depolarization (e.g., a Q-wave, an R-wave, etc.) and a second fiducial marker indicative of a subsequent mitral valve closure (MVC) occurring during the same cardiac cycle. Such time intervals are used for detecting atrioventricular (AV) dissociation. The AV dissociation may, in turn, be used for discriminating between a supraventricular tachyarrhythmia (SVT) and a ventricular tachyarrhythmia (VT) or for any other diagnostic or therapeutic purpose. The AV dissociation and/or SVT/VT discrimination information may be communicated from an implantable cardiac rhythm management device to an external interface and/or used to determine the nature of therapy delivered to the subject. In a further example, amplitudes indicative of the MVCs are also used for determining whether AV dissociation exists.

Abstract: The invention relates to an arrangement for coding heart rate information, comprising means (600A, 600B) for measuring a person's heart beat intervals and means for storing (648) the measured heart beat interval information. The arrangement comprises means (654) for coding the heart beat interval information stored in the storing means (648) into music, the coding means comprising means (660) for selecting the rhythm of the music on the basis of the measured heart beat intervals.

Abstract: In a local stethoscope unit, acoustic auscultation sounds picked up by the stethoscope chest piece assembly of a local stethoscope unit are converted to analog electrical signals and then converted to digital signals. The digital signals are conveyed to a data communications system, having data communications device and a data communication channel. The digital signals are transmitted over the digital communications system to a remote stethoscope receiving unit. The remote stethoscope unit converts the digital signals back to the original analog signals suitable for listening.

Abstract: A combined audio and electrical anatomy-signal sensor which is designed to collect, essentially from a selected, common anatomical site, related audio and electrical anatomical signals, such as heart-produced signals. The sensor includes a unique body structure which is designed to function both as a part of the audio-information gathering structure, and as a part of electrical electrode structure for gathering electrical signals. Chamber space is provided within this body for receiving and containing desired electrical circuitry, in the form of circuit-board-supported electrical components, which may be designed to perform any one of a number of different functions relative to signal gathering and transferring at and from an anatomical site.

Abstract: There is provided herein a first preferred arrangement of the instant invention, wherein an electronic patient monitor utilizes a computer CPU as an alarm signal generator, which CPU is preferably directly connected to a power amplifier and/or a speaker without an intervening (or subsequent) conventional volume control. The alarm signal is preferably expressed as a series of square waves. The volume of the alarm signal as heard through the speaker is controlled by varying the width of the square waves that represent the alarm signal with the duty cycle of the square waves being shortened to reduce the output alarm volume and lengthened to increase it.

Abstract: A method and apparatus for gathering high-quality anatomical audio signals. Practice of the invention, which is illustrated herein in the context of heart-produced signals, is based upon gathering, and competitively processing audio signals collected simultaneously from two adjacent anatomical sites. Competitive processing examines these two signals in light of certain selected “quality” parameters, and thereby selects the better signal at a user-selected point in time.

Abstract: A sensor designed to collect and convey single-site-related, body-produced electrical and acoustic signals, such as those related to heart activity, where electrical electrode and audio transducer structures lie along a common axis. A portion of the electrical electrode structure forms an acoustic isolating shroud around the audio transducer.

Abstract: A method of diagnosing pathologic heart conditions in which a time series of heart sounds is filtered and parsed into a sequence of individual heart cycles. A systolic interval as well as systolic sub-intervals are identified for each heart cycle. The systolic intervals and ECG peaks are then digitally filtered to optimize for click detection. For each heartcycle, systole time limits are determined, a time series of the transform at specific wavelet scales are input to a Neyman-Pearson “constant false alarm rate” (CFAR) detector to identify anomalously high wavelet coefficients, and a vector of detections vs. time is created. The series of anomalously high detections (one series for each heart cycle) are then assembled into a matrix and convolved with an averaging vector yielding detection statistics across heart cycles and time intervals consistent with an observed spread of click occurrence times.

Abstract: A method of diagnosing pathologic heart conditions in which a time series of heart sounds is filtered and parsed into a sequence of individual heart cycles. A systolic interval as well as systolic sub-intervals are identified for each heart cycle. An energy value is computed for the systolic sub-interval of one or more heart cycles. The energy value computed is proportional to the energy level associated with the filtered series of heart sounds. A composite energy value is then computed for the systolic sub-intervals of one or more heart cycles and compared to a threshold level in order to distinguish between a normal heart and a pathologic heart. The system corresponding to the method is comprised of a portable computing device that manages data collection and stores data collected from new patients, and analyzes data.

Abstract: A system and a method for monitoring a physiological parameter of a patient providing a measurement-modulated acoustic signal (7) after/when a measurement value of the monitored physiological parameter exceeds an alarm limit.

Abstract: Myocardial performance is assessed using a combination of electrical and mechanical criteria. More specifically, this assessment may be based on a QT interval based on electrogram (EGM) readings and on first and second heart sounds. The timing relationships between the QT interval and the first and second heart sounds can be used to evaluate certain systolic, diastolic, and systolic/diastolic parameters relating to myocardial performance. In addition, these parameters may be used to automatically drive therapies. For example, myocardial performance parameters obtained from the QT interval and from the timing of the first and second heart sounds may be used to optimize the AV delay and to optimize multisite pacing.

Abstract: A system and method for use in an implantable cardiac device permits the monitoring of progression and regression in heart disease, such as congestive heart failure. During a monitoring period, a sensing circuit produces an electrogram signal of the patient's heart and a sound sensor produces a phonocardiogram of the patient's heart. A processor determines a predetermined characteristic of the heart sounds, such as amplitude, time intervals between selected heart sounds, and time intervals between selected heart sound and selected electrogram features for each cardiac cycle occurring during a monitoring period. The predetermined characteristics are thereafter averaged and stored in a memory for later retrieval. Relative changes in the average time intervals over time provides an indication of the progression or regression of the heart disease.

Abstract: A biomagnetic field measurement apparatus includes a bed which holds a subject to be inspected in a shielded room. A cryostat holds a plurality of SQUID magnetometers at low temperature. The cryostat is arranged in the shielded room and the plurality of SQUID magnetometers detect a magnetic field generated from the subject. A driving and detecting circuit drives the plurality of SQUID magnetometers and detects signals therefrom that are processed by a computer. A display that is arranged in the shielded room displays data for viewing by an operator.

Abstract: A computer site includes a data generating source. The source may include a device (e.g. a heart monitor) which may be manipulated by the patient to sense a biological function or condition such as a heart beat. The device outputs an audible signal in response to the monitored condition. A computer that can be operated by the patient or other initial user at the site runs a program that processes an electric signal generated in response to the audible signal as received through a microphone connected to the computer. The program is downloaded or otherwise accessed through a computer communications network (e.g. Internet). The computer sends resulting data signals over this network. Using a plurality of the foregoing components, any number of patients (or other users) that can access the computer communications network can provide real-time information about their personal medical condition (or other generated data) to their personal medical care providers (or other remote end users).

Abstract: A tool for measuring the oral cavity. The tool includes a first measuring member having a first leg portion and a dial portion with graduations provided thereon and a second measuring member having a second leg portion and a pointer. The pointer moves across the dial upon pivotal movement of measuring members such that the pointer designates one of the graduations to indicate the spacing between the leg portions. Second graduations provided on one of the measuring members are indicative of a second measured value. The tool also includes a support member positionable in the oral cavity of a patient with the patient biting down on the upper and lower bite surfaces of the support. The support includes an opening shaped to slidably receive and support the first leg portion and a slot offset from the opening. The slot is shaped to slidably receive the second leg portion as the second measuring member is pivoted relative to the first measuring member.

Abstract: An implantable monitor for collecting and storing for later telemetric readout physiologic data relating to cardiopulmonary performance. The monitor device includes an accelerometer and associated signal processing circuitry for analyzing the accelerometer output signal and deriving therefrom activity, respiratory, pulse pressure and heart sound information helpful in assessing the efficacy of therapy being rendered to the patient.

Abstract: The present invention relates to a sensing device for capturing acoustic heart sounds. The sensing device has a diaphragm formed from a piezoelectric transducer material which generates excitation signals in response to acoustic and vibratory energy outputs. The sensing device includes metallization layers on the diaphragm for receiving and transmitting the excitation signals to an output display device via associated electrical contacts and electrical leads and also includes a layer of adhesive material for coupling the sensing device to the subject. The sensing device further includes snap connectors for allowing the device to be quickly disengaged from electrical leads and discarded. A patch sensor device is disclosed which enables acoustic outputs to be triangulated and pinpointed.