Abstract: Methods, systems and devices are provided for monitoring respiratory disorders based on monitored factors of a photoplethysmography (PPG) signal that is representative of peripheral blood volume. The monitored factors can be respiratory effort as well as respiratory rate and/or blood oxygen saturation level. The systems and devices may or may not be implanted in a patient.

Abstract: Methods, systems and devices are provided for reducing the amount of data, processing and/or power required to analyze hemodynamic signals such as photoplethysmography (PPG) signals, pressure signals, and impedance signals. In response to detecting a specific event associated with a cyclical body function, a hemodynamic signal is continuously sampled during a window following the detecting of the specific event, wherein the window is shorter than a cycle associated with the cyclical body function. The hemodynamic signal is then analyzed based on the plurality of samples. This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.

Abstract: Methods and systems for performing pacing interval optimization are provided. One or more optimum pacing interval is determined for each of a plurality of different ranges of heart rate, different levels of autonomic tone, different body temperature ranges, or combinations thereof. The information (e.g., measures of hemodynamic response) collected to perform pacing interval optimization can be collected and stored in a table over disjoint periods of time. Such measures of hemodynamic performance are preferably relative measures, but can alternatively be absolute measures.

Abstract: Methods, systems and devices are provided for reducing the amount of data, processing and/or power required to analyze hemodynamic signals such as photoplethysmography (PPG) signals, pressure signals, and impedance signals. In response to detecting a specific event associated with a cyclical body function, a hemodynamic signal is continuously sampled during a window following the detecting of the specific event, wherein the window is shorter than a cycle associated with the cyclical body function. The hemodynamic signal is then analyzed based on the plurality of samples. This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.

Abstract: Methods, systems and devices are provided for reducing the amount of data, processing and/or power required to analyze hemodynamic signals such as photoplethysmography (PPG) signals, pressure signals, and impedance signals. In response to detecting a specific event associated with a cyclical body function, a hemodynamic signal is continuously sampled during a window following the detecting of the specific event, wherein the window is shorter than a cycle associated with the cyclical body function. The hemodynamic signal is then analyzed based on the plurality of samples.

Abstract: Hemodynamic signals, such as photoplethysmography (PPG) signals, pressure signals, and impedance signals, are sampled once per cyclical body cycle to reduce the amount of data, processing and/or power required to analyze the hemodynamic signals.

Abstract: Methods and systems for performing pacing interval optimization are provided. One or more optimum pacing interval is determined for each of a plurality of different ranges of heart rate, different levels of autonomic tone, different body temperature ranges, or combinations thereof. The information (e.g., measures of hemodynamic response) collected to perform pacing interval optimization can be collected and stored in a table over disjoint periods of time. Such measures of hemodynamic performance are preferably relative measures, but can alternatively be absolute measures.

Abstract: Methods and systems for performing pacing interval optimization are provided. One or more optimum pacing interval is determined for each of a plurality of different ranges of heart rate, different levels of autonomic tone, different body temperature ranges, or combinations thereof. The information (e.g., measures of hemodynamic response) collected to perform pacing interval optimization can be collected and stored in a table over disjoint periods of time. Such measures of hemodynamic performance are preferably relative measures, but can alternatively be absolute measures.

Abstract: Methods, systems and devices are provided for monitoring respiratory disorders based on monitored factors of a photoplethysmography (PPG) signal that is representative of peripheral blood volume. The monitored factors can be respiratory effort as well as respiratory rate and/or blood oxygen saturation level. The systems and devices may or may not be implanted in a patient.

Abstract: Methods and devices are provided for reducing motion artifacts when measuring blood oxygen saturation. A portion of the light having the first wavelength, a portion of light having the second wavelength and a portion of the light having the third wavelength are received. A first signal is produced based on the received portion of light having the first wavelength. Similarly, a second signal is produced based on the received portion of light having the second wavelength, and a third signal is produced based on the received portion of light having the third wavelength. A difference between the second signal and the first signal is determined, wherein the difference signal is first plethysmography signal. Similarly, a difference is determined between the third signal and the first signal to produce a second plethysmography signal. Blood oxygen saturation is then estimated using the first and second plethysmography signals.

Abstract: Methods, systems and devices are provided for monitoring respiratory disorders based on monitored factors of a photoplethysmography (PPG) signal that is representative of peripheral blood volume. The monitored factors can be respiratory effort as well as respiratory rate and/or blood oxygen saturation level. The systems and devices may or may not be implanted in a patient.

Abstract: Embodiments of the present invention relate to implantable sensors for obtaining hemodynamic data and/or physiologic data. More specifically, embodiments of the present invention enable additional sensing hardware to be added into implantable devices more quickly and less expensively. Additionally, embodiments of the present invention enable such adding of additional sensing hardware with little or no effect on the conventional functions of the implantable device to which the sensor hardware is being added.

Abstract: Analysis of metabolic gases by an implantable medical device allows the assessment of the status of a congestive heart failure patient by providing for the assessment of cardiac output. The present invention is directed to an implanted medical device configured to measure concentrations of metabolic gases in the blood to determine cardiac output of a patient. The device is also configured to measure changes in the cardiac output of a patient. The present invention is also directed to a method of measuring cardiac output by an implanted medical device. Further, the detection of changes in cardiac output utilizing an implanted medical device as disclosed herein is useful in a method of detecting exacerbation of congestive heart failure. The implanted medical device can also be used to pace a heart to modify cardiac output in a patient.

Abstract: Techniques are provided for rapidly optimizing control parameters of pacemakers or implantable cardioverter defibrillators. Briefly, the heart is paced using different sets of control parameters during a sequence of consecutive short evaluation periods of equal duration, which each last only about 5-12 seconds. Transient cardiac performance is monitored during each of the short evaluation phases and optimal parameter settings are then estimated based on changes in the transient cardiac performance from one parameter setting to another. By using a series of consecutive short evaluation periods of equal duration, rather than switching between short test periods and longer baseline periods, the overall duration of the test can be reduced as compared to predecessor techniques that require long intervening baseline periods.

Abstract: Analysis of metabolic gases by an implantable medical device allows the assessment of the status of a congestive heart failure patient by providing for the assessment of cardiac output. The present invention is directed to an implanted medical device configured to measure concentrations of metabolic gases in the blood to determine cardiac output of a patient. The device is also configured to measure changes in the cardiac output of a patient. The present invention is also directed to a method of measuring cardiac output by an implanted medical device. Further, the detection of changes in cardiac output utilizing an implanted medical device as disclosed herein is useful in a method of detecting exacerbation of congestive heart failure. The implanted medical device can also be used to pace a heart to modify cardiac output in a patient.

Abstract: A method and device, such as an implantable cardiac device, for motion and noise immunity in hemodynamic measurement is presented. The method includes obtaining a template waveform representing hemodynamic performance of a heart during a first hemodynamic state and obtaining an autocharacterization measure from an autocharacterization (e.g., autocorrelation) of the template waveform. The method further includes obtaining a test waveform during a second hemodynamic state, performing a cross-characterization (e.g., cross-correlation) of the template waveform and test waveform to identify a cross-characterization measure, and comparing the autocharacterization measure with the cross-characterization measure as a measurement of hemodynamic status of the second hemodynamic state. The device includes hardware and/or software for performing the described method.

Abstract: Methods, systems and devices are provided for reducing the amount of data, processing and/or power required to analyze hemodynamic signals such as photoplethysmography (PPG) signals, pressure signals, and impedance signals. Methods, systems and devices are also provided for reducing the amount of processing required to determine blood oxygen (O2) saturation levels.

Abstract: An implantable cardiac stimulation device is configured to measure selected ventricular contraction parameters and possibly apply stimulation therapy based on the ventricular contraction parameters. In accordance with one aspect, the ventricular contraction parameters include impedance values that correspond to the volume of fluid in the right ventricle and the left ventricle. In accordance with another aspect, the ventricular contraction parameters include motion values that correspond to heart sounds/motion in the right ventricle and the left ventricle. The ventricular contraction parameters can be used to form pseudo P-V loop from which treatment decisions can be made.

Abstract: An implantable cardiac stimulation device is configured to measure selected ventricular contraction parameters and possibly apply stimulation therapy based on the ventricular contraction parameters. In accordance with one aspect, the ventricular contraction parameters include impedance values that correspond to the volume of fluid in the right ventricle and the left ventricle. In accordance with another aspect, the ventricular contraction parameters include motion values that correspond to heart sounds/motion in the right ventricle and the left ventricle. The ventricular contraction parameters can be used to form pseudo P-V loop from which treatment decisions can be made.

Abstract: A parameter in an implantable cardiac therapy device (ICTD) is optimized based on analysis of a hemodynamic signal. The method includes receiving a hemodynamic signal; filtering the hemodynamic signal data to isolate low frequency data present therein; and sampling the low frequency data according to a sampling algorithm. The parameter is optimized in the ICTD based on an analysis of the sampled low frequency data.