Abstract: Methods and/or devices are disclosed herein for monitoring cardiac impedance signal and delivering therapy to a patient's heart based upon the monitored cardiac impedance.

Abstract: A system and method is provided to measure intrathoracic complex impedance and to identify and indicate disease conditions based on the impedance measurements. Multiple impedance vectors may be taken into account, and an optimal vector may be selected to provide the most useful impedance measurement for the identification and indication of disease conditions.

Abstract: An implantable medical device and associated method to determine an optimal control parameter setting for controlling a cardiac therapy that includes a therapy delivery module to deliver cardiac pacing signals at a plurality of pacing rates, and an admittance measurement module to determine admittance signals associated with each of the plurality of pacing rates. A control unit determines metrics of hemodynamic performance corresponding to each of the plurality of pacing rates in response to the determined admittance signals, identifies pacing rates of the plurality of pacing rates as rejected rates in response to the determined metrics of hemodynamic performance, and determines a pacing rate of the plurality of pacing rates as an optimal rate for delivering the cardiac therapy in response to the identified pacing rates.

Abstract: Methods and/or devices are disclosed herein for monitoring cardiac impedance signal and delivering therapy to a patient's heart based upon the monitored cardiac impedance.

Abstract: Methods and/or devices used in delivering cardiac resynchronization therapy based on a plurality of device parameters (e.g., A-V delay, V-V delay, etc.) are optimized by setting a device parameter based on selection data. The selection data may be acquired by acquiring temporal fiducial points (e.g., heart sounds) associated with at least a part of a systolic portion of at least one cardiac cycle and/or temporal fiducial points associated with at least a part of a diastolic portion of the at least one cardiac cycle for each of a plurality of electrode vector configurations, and extracting measurements from the intracardiac impedance signal acquired for each of a plurality of electrode vector configurations based on the temporal fiducial points. The acquired selection data may be scored and used to optimize the device parameter.

Abstract: Methods and/or devices are disclosed herein for monitoring cardiac impedance signal and delivering therapy to a patient's heart based upon the monitored cardiac impedance.

Abstract: Methods and/or devices used in delivering cardiac resynchronization therapy based on a plurality of device parameters (e.g., A-V delay, V-V delay, etc.) are optimized by setting a device parameter based on selection data. The selection data may be acquired by acquiring temporal fiducial points (e.g., heart sounds) associated with at least a part of a systolic portion of at least one cardiac cycle and/or temporal fiducial points associated with at least a part of a diastolic portion of the at least one cardiac cycle for each of a plurality of electrode vector configurations, and extracting measurements from the intracardiac impedance signal acquired for each of a plurality of electrode vector configurations based on the temporal fiducial points. The acquired selection data may be scored and used to optimize the device parameter.

Abstract: Methods and/or devices used in delivering cardiac resynchronization therapy based on a plurality of device parameters (e.g., A-V delay, V-V delay, etc.) are optimized by setting a device parameter based on selection data. The selection data may be acquired by acquiring temporal fiducial points (e.g., heart sounds) associated with at least a part of a systolic portion of at least one cardiac cycle and/or temporal fiducial points associated with at least a part of a diastolic portion of the at least one cardiac cycle for each of a plurality of electrode vector configurations, and extracting measurements from the intracardiac impedance signal acquired for each of a plurality of electrode vector configurations based on the temporal fiducial points. The acquired selection data may be scored and used to optimize the device parameter.

Abstract: Methods and/or devices used in delivering cardiac resynchronization therapy based on a plurality of device parameters (e.g., A-V delay, V-V delay, etc.) are optimized by setting a device parameter based on selection data. The selection data may be acquired by acquiring temporal fiducial points (e.g., heart sounds) associated with at least a part of a systolic portion of at least one cardiac cycle and/or temporal fiducial points associated with at least a part of a diastolic portion of the at least one cardiac cycle for each of a plurality of electrode vector configurations, and extracting measurements from the intracardiac impedance signal acquired for each of a plurality of electrode vector configurations based on the temporal fiducial points. The acquired selection data may be scored and used to optimize the device parameter.

Abstract: Methods and/or devices used in delivering cardiac resynchronization therapy based on a plurality of device parameters (e.g., A-V delay, V-V delay, etc.) are optimized by setting a device parameter based on selection data. The selection data may be acquired by acquiring temporal fiducial points (e.g., heart sounds) associated with at least a part of a systolic portion of at least one cardiac cycle and/or temporal fiducial points associated with at least a part of a diastolic portion of the at least one cardiac cycle for each of a plurality of electrode vector configurations, and extracting measurements from the intracardiac impedance signal acquired for each of a plurality of electrode vector configurations based on the temporal fiducial points. The acquired selection data may be scored and used to optimize the device parameter.

Abstract: Techniques for estimating a cardiac chamber or vascular pressure based upon impedance are described. A device or system may measure an impedance between at least two electrodes implanted within or proximate to a cardiovascular system. The device or system may estimate a pressure of an element of the cardiovascular system based on a relationship between impedance and volume of the element, and based on a empirical relationship between the volume and the pressure. The device or system may also estimate the dimension of the element based on the impedance-volume relationship, or other characteristics based on the impedance. Because the impedance measurements may be obtained, in some examples, by using electrodes and leads implanted within the cardiovascular system and coupled to an implantable medical device, a practical estimation of a cardiovascular pressure can be obtained on a chronic basis without requiring the use other invasive sensors, such as micronanometer transducers.

Abstract: A medical device and associated method for delivery of a cardiac therapy that includes determining a first impedance signal along a thoracic electrode vector extending within a portion of a thoracic cavity, determining a second impedance signal along an extra-thoracic electrode vector extending outside the thoracic cavity, comparing first amplitude measurements corresponding to the first impedance signals and second amplitude measurements corresponding to the second impedance signals, comparing first slope measurements corresponding to the first impedance signals and second slope measurements corresponding to the second impedance signals, and determining delivery of the cardiac therapy in response to the comparing.

Abstract: A system and method is provided to measure intrathoracic complex impedance and to identify and indicate disease conditions based on the impedance measurements. Multiple impedance vectors may be taken into account, and an optimal vector may be selected to provide the most useful impedance measurement for the identification and indication of disease conditions.

Abstract: An implantable cardioverter defibrillator evaluates the hemodynamic stability of an arrhythmia to determine whether or not to defibrillate. The device obtains cardiac pressure and cardiac impedance data and evaluates a phase relationship between these parameters. Hemodynamically stable rhythms will result in an out of phase relationship.

Abstract: A system and method is provided to measure intrathoracic complex impedance and to identify and indicate disease conditions based on the impedance measurements. Multiple impedance vectors may betaken into account, and an optimal vector may be selected to provide the most useful impedance measurement for the identification and indication of disease conditions.

Abstract: A medical device and associated method for delivery of a cardiac therapy that includes determining a first impedance signal along a thoracic electrode vector extending within a portion of a thoracic cavity, determining a second impedance signal along an extra-thoracic electrode vector extending outside the thoracic cavity, comparing first amplitude measurements corresponding to the first impedance signals and second amplitude measurements corresponding to the second impedance signals, comparing first slope measurements corresponding to the first impedance signals and second slope measurements corresponding to the second impedance signals, and determining delivery of the cardiac therapy in response to the comparing.

Abstract: A medical device and associated method for monitoring a fluid status of a patient that includes determining a first impedance signal along an electrode vector comprising a portion of a thoracic cavity, determining a second impedance signal along an extra-thoracic electrode vector, and determining a fluid status measurement in response to the determined first impedance signal and the determined second impedance signal

Abstract: Methods and/or devices are disclosed herein for monitoring cardiac impedance signal and delivering therapy to a patient's heart based upon the monitored cardiac impedance.

Abstract: Methods and/or devices are disclosed herein for monitoring cardiac impedance signal and delivering therapy to a patient's heart based upon the monitored cardiac impedance.

Abstract: An implantable medical device and associated method detect obstructed inspiration by monitoring an blood pressure signal. A respiration signal is monitored and a phase of respiratory inspiration is detected from the respiration signal. A trend in the pressure signal is measured during the inspiration phase. Obstructed inspiration for the inspiration phase is detected in response to the measured the trend.