Patent application number | Description | Published |
20090171220 | METHODS FOR DETECTING AND MONITORING SLEEP DISORDERED BREATHING USING AN IMPLANTABLE MEDICAL DEVICE - A method of identifying sleep disordered breathing (SDB) in a patient includes monitoring a hemodynamic pressure, deriving high, middle, and low values representative of the distribution of the hemodynamic pressure over a storage interval, measuring a ratio of a lower range to a full range of the hemodynamic pressure based on the derived high, middle, and low values, and using the ratio to determine whether the patient has experienced an SDB episode. Certain embodiments of the invention compare the ratio to a threshold value to identify the occurrence of an SDB episode, while other embodiments of the invention identify the occurrence of an SDB episode by monitoring for a simultaneous increase in both the ratio and the full range of the hemodynamic pressure. In certain other embodiments of the invention, activity level and/or duration criteria may be employed to confirm the occurrence of an SDB episode detected using the ratio. | 07-02-2009 |
20090209876 | Method and apparatus for continuous pulse contour cardiac output - A system and method are provided for sensing cardiac electrogram (EGM) signals and ventricular pressure signals and for using the sensed EGM and sensed pressure signals for estimating stroke volume (SV). A measure of cardiac output can be computed from the estimated SV and a heart rate determined from the EGM signals. The sensed ventricular pressure signal and the sensed EGM signal are used to derive landmark points such as an estimated pulmonary diastolic pressure, a mean pulmonary artery pressure, a peak right ventricular pressure (RVP), and various time intervals used in computing an area or a pulse contour integral. The pulse contour integral is used to estimate SV. The estimated pulmonary diastolic pressure, mean pulmonary artery pressure and CO computed from the estimated SV can be used to compute a pulmonary vascular resistance. | 08-20-2009 |
20090275843 | SYSTEM AND METHOD OF DETERMINING ARTERIAL BLOOD PRESSURE AND VENTRICULAR FILL PARAMETERS FROM VENTRICULAR BLOOD PRESSURE WAVEFORM DATA - A system and method of determining hemodynamic parameters uses sensed ventricular blood pressure during a portion of ventricular pressure waveform following peak pressure. An estimated arterial diastolic pressure is based upon an amplitude of the sensed ventricular pressure corresponding to a time at which a first derivative of ventricular pressure as a function of time is at a minimum (dP/dt | 11-05-2009 |
20090299198 | ESTIMATING PULMONARY ARTERY DIASTOLIC PRESSURE - A method for estimating pulmonary artery diastolic pressure, for a single heart beat, includes establishing a time window for sampling and storing pressure data points from a right ventricular pressure transducer. The time window may be established according to predetermined parameters and/or according to one or more triggering events. An approximate time at which the pulmonary artery valve opens is determined, either via the sampled pressure data points, or via another form of more direct monitoring, during the time window, in order to estimate the pulmonary artery diastolic pressure. A plurality of sets of N pressure data points may be collected, from the sampled data, and, for each collected set, a weighted sum is calculated. Each weighted sum may be employed to evaluate a quality of the sampled data and/or to estimate the pulmonary artery diastolic pressure, if the more direct monitoring of the pulmonary artery valve is not employed. | 12-03-2009 |
20100056885 | IMPLANTABLE BIOSENSOR DEVICES FOR MONITORING CARDIAC MARKER MOLECULES - An implantable biosensor system is disclosed for determining levels of cardiac markers in a patient to aid in the diagnosis, determination of the severity and management of cardiovascular diseases. The sensor includes nanowire sensor elements having a biological recognition element attached to a nanowire transducer that specifically binds to the cardiac marker being measured. Each of the sensor elements is associated with a protective member that prevents the sensor element from interacting with the surrounding environment. At a selected time, the protective member may be disabled, thereby allowing the sensor element to begin sensing signals within a living body. | 03-04-2010 |
20100076322 | METHOD AND APPARATUS FOR DETERMINING A RESPIRATION PARAMETER IN A MEDICAL DEVICE - A method of determining a respiration parameter in a medical device in which pressure signals are sensed to generate corresponding sample points, and a breath detection threshold is continuously adjusted in response to the generated sample points to generate a current adjusted breath detection threshold. A current generated sample point is compared to the current adjusted breath detection threshold, and the continuous adjusting of the breath detection threshold is suspended and the breath detection threshold is equal to the most current adjusted breath detection threshold generated prior to the suspending in response to the comparing. A next sample point, generated subsequent to the suspending, is compared to the set breath detection threshold, and the respiration parameter is determined in response to the comparing of a next sample point to the set breath detection threshold. | 03-25-2010 |
20100076323 | METHOD AND APPARATUS FOR DETERMINING A RESPIRATION PARAMETER IN A MEDICAL DEVICE - An apparatus for determining a respiration parameter in a medical device in which a pressure sensor senses pressure signals, and a signal processor, coupled to the pressure sensor, receives the sensed pressure signals and generates corresponding sample points. A microprocessor continuously adjusts a breath detection threshold in response to the generated sample points to generate a current adjusted breath detection threshold, compares a current generated sample point to the current adjusted breath detection threshold, suspends the continuous adjusting of the breath detection threshold and sets the breath detection threshold equal to the most current adjusted breath detection threshold generated prior to the suspending, and determines the respiration parameter in response to a comparing of a next generated sample point to the set breath detection threshold | 03-25-2010 |
20100076324 | METHOD AND APPARATUS FOR DETECTING RESPIRATORY EFFORT IN A MEDICAL DEVICE - A medical device for determining a respiratory effort having a pressure sensor to sense pressure signals, a housing having system components positioned therein, and a microprocessor positioned within the housing, wherein the microprocessor detects an inspiration and an expiration in response to the pressure signals, detects a breath in response to the detected inspiration and the detected expiration, and determines the respiratory effort in response to the detected breath. | 03-25-2010 |
20100076325 | METHOD AND APPARATUS FOR DETERMINING RESPIRATORY EFFORT IN A MEDICAL DEVICE - A method of determining respiratory effort in a medical device in which pressure signals are sensed to generate corresponding sample points, an inspiration and an expiration are detected in response to the sensed pressure signals, a breath is detected in response to the detected inspiration and the detected expiration, and the respiratory effort is determined in response to the detected breath. | 03-25-2010 |
20100076514 | FILTERING OF A PHYSIOLOGIC SIGNAL IN A MEDICAL DEVICE - A system and method for filtering a pressure signal in a medical device in which a sensor terminal senses the pressure signal, an electrode terminal receives cardiac electrical signals, a signal filtering system filters the sensed pressure signal in response to a determined heart rate to generate a heart-rate dependent frequency response, and a microprocessor derives a respiration signal in response to the heart rate dependent frequency response, and determines metrics of hemodynamic function in response to the derived respiration signal. | 03-25-2010 |
20100113888 | HEART FAILURE DECOMPENSATION DETERMINATION - Heart failure decompensation is detected by sensing at least one physiological signal. Values of at least two different heart failure variables are derived using one or more physiological signals and a threshold for the first heart failure variable is adjusted in response to the value of the second heart failure variable. The value of the first heart failure variable is compared to first threshold for detecting a heart failure condition. | 05-06-2010 |
20100113890 | HEART FAILURE PATIENT MANAGEMENT USING AN IMPLANTABLE MONITORING SYSTEM - An implantable medical device system and method provide physiological variable monitoring for use in patient management. A target value for a physiological variable and formulations for computing metrics of the physiological variable are stored. Values of the physiological variable are determined from a sensed physiological signal and are used to compute a selected metric. The metric is compared to the stored target value. | 05-06-2010 |
20100114230 | Method and Apparatus to Detect Ischemia With A Pressure Sensor - The present disclosure provides an apparatus and method of detecting ischemia with a pressure sensor. The method can include obtaining a pressure signal and determining a pressure rate of change. The method can also include identifying at least one of impaired relaxation and impaired contractility in order to detect ischemia. | 05-06-2010 |
20100210954 | SYSTEM AND METHOD FOR DETECTING ARTIFACTUAL HEMODYNAMIC WAVEFORM DATA - A system and method for cardiovascular analysis includes an implantable medical device capable of generating hemodynamic pressure waveform data based upon sensed pressure. Hemodynamic waveform data is analyzed to identify artifactual data represented in the hemodynamic waveform. | 08-19-2010 |
20100217135 | METHOD AND SYSTEM FOR INTERPRETING HEMODYNAMIC DATA INCORPORATING PATIENT POSTURE INFORMATION - Systems and methods for improving hemodynamic data interpretation by accounting for the effects of patient posture is disclosed. In certain embodiments, a posture signal is acquired and used to categorize hemodynamic data according to posture to facilitate distinguishing posture-related changes in acquired hemodynamic data from those due to pathophysiologic changes. Posture information may be used to normalize data acquired in various postures to facilitate interpretation of such data. Baseline measurements of hemodynamic data acquired in various postures may also be used to subsequently detect changes in patient posture without the need for an implanted posture sensor. | 08-26-2010 |
20110077574 | SYSTEM AND METHOD TO REGULATE ULTRAFILTRATION - A medical device system including a physiological sensor and ultrafiltration unit senses a physiological signal in a patient and computes a fluid status measurement of the patient using the physiological signal. Ultrafiltration therapy is delivered to the patient according to a therapy delivery control parameter established in response to the fluid status measurement. | 03-31-2011 |
20110077616 | METHODS FOR GUIDING HEART FAILURE DECOMPENSATION THERAPY - An implantable medical device system and associated method for use in guiding an acute decompensated heart failure therapy set an optimal fluid status measurement level. A physiological sensor signal sensed by an implantable medical device is used to compute the fluid status measurement. A target rate of change of the fluid status measurement is computed for guiding the therapy. | 03-31-2011 |
20110105927 | DETECTION OF WAVEFORM ARTIFACT - An implantable medical device system including a physiological sensor detects signal artifact in a signal waveform acquired by the sensor. Features of individual waveforms in the sensor signal are extracted. Sample waveforms are classified by expert observation into at least two classes including an artifact class. A distribution range for each of the extracted features from the sample waveforms is determined for each of the classes. Waveform classification criteria are established in response to the determined distribution ranges. | 05-05-2011 |
20110106191 | IMPLANTABLE MEDICAL DEVICE NOISE MODE - Techniques for activating an alternative operating mode in an implantable medical device based on a determination that the device is within a relatively high noise environment or otherwise exposed to relatively high noise. The implantable medical device can automatically detect its presence in a high noise environment and automatically revert to the alternative operating mode, the device may be manually switched to alternative operating mode, or a hybrid manual/automatic approach may be used to switch the device to alternative operating mode. | 05-05-2011 |
20110172544 | METHOD FOR CONTINUOUS BAROREFLEX SENSITIVITY MEASUREMENT - A medical device and method for determining baroreflex sensitivity (BRS) based on one or more respiration cycles. The BRS determination may be performed continuously based on measurements of heart rate, blood pressure, and respiration cycles. | 07-14-2011 |
20110208078 | METHODS OF IDENTIFYING AND/OR ASSESSING CARDIAC ARRHYTHMIAS USING AN IMPLANTABLE MEDICAL DEVICE - Apparatus using one or more modes of statistical analysis with one or more monitored parameters of a patient's heart to identify and/or assess arrhythmias. Through use of the one or more modes of statistical analysis, a medical professional can be aided during evaluation of patient data for diagnosis of the patient. At least one of the monitored parameters may include one or more values used representatively for storage intervals of a selected length. As such, for each storage interval, a value may be determined for the one monitored parameter occurring at an upper percentile and a lower percentile. In addition, a median value may be determined for the one monitored parameter for each storage interval. Over a plurality of the storage intervals, these determined values can be used in one or more modes of statistical analysis to better identify and assess the arrhythmias. | 08-25-2011 |
20110251496 | VOLUME DEPLETION DETECTION - Detection of volume depletion, particularly after an incidence of volume overload is disclosed. Various methods, systems, and devices are disclosed that sense and analyze a physiological parameter related to a patient's fluid level in order to warn patients of potentially dangerous volume depletion conditions while minimizing false notifications. | 10-13-2011 |
20110301474 | Heart Failure Monitor Quicklook Summary for Patient Management Systems - Continuous remote monitoring of patients based on data obtained from an implantable hemodynamic monitor provides an interactive patient management system. Using network systems, patients are remotely monitored to continuously diagnose and treat heart-failure conditions. A screen displayable summary provides continuous feedback and information to physicians, patients and authorized third parties. The quick look summary includes various sites and presentation tailored to match the patients' and physicians' needs. The quick look summary further includes intelligent features that understand and retain the user's interests, preferences and use patterns. Patients, physicians and other caregivers are seamlessly connected to monitor and serve the chronic needs of heart-failure patients in a reliable and economic manner. | 12-08-2011 |
20120108984 | INTEGRATED PATIENT CARE - A therapy regimen, e.g., a contingent medication prescription, may be created and automatically distributed to a patient via an integrated patient care system. A clinician may create therapy instructions by at least associating patient conditions with one or more therapy regimens, e.g., medication prescriptions. In some examples, the integrated patient care system may present historical condition data to the clinician to aid the clinician with creating and/or updating the therapy instructions specific to the patient. A therapy module of the integrated patient care system may use the therapy instructions to automatically select a therapy regimen from the therapy instructions based on a patient condition detected based on a sensed physiological parameter. The physiological parameter of the patient may be sensed by an implanted or external sensor. In some examples, the therapy regimen can be presented to the patient according to a predetermined schedule or in response to the detected condition. | 05-03-2012 |
20120197088 | DETECTION OF WAVEFORM ARTIFACT - A medical device system including a physiological sensor is configured to perform a method for detecting signal artifact in a signal waveform acquired by the sensor. A signal waveform is sensed in a patient using the physiological sensor and a fiducial point associated with the sensed waveform is identified. A point value is established using the fiducial point. Signal artifact is detected in response to the established point value and an established threshold, and at least a portion of the signal waveform is rejected in response to detecting signal artifact. | 08-02-2012 |
20120283580 | VERIFICATION OF PRESSURE METRICS - An example system may include at least one pressure sensor configured to measure a cardiovascular pressure signal and another medical device configured to measure an electrical depolarization signal of the heart. The system determines a plurality of cardiovascular pressure metrics based on the measured cardiovascular pressure signal, including at least one cardiovascular pressure metric indicative of a timing of at least one cardiac pulse. The system also determines a metric indicative of a timing of at least one heart depolarization within the measured electrical depolarization signal. The system compares the timing of the at least one cardiac pulse to the timing of the at least one depolarization, and determines whether to discard the plurality of cardiovascular pressure metrics based on whether the timings substantially agree. | 11-08-2012 |
20120290032 | TECHNIQUES FOR MODIFYING BREATHING RATE USING CARDIAC PACING - A method includes controlling a cardiac pacing rate of an implantable medical device (IMD) to control a heart rate of a patient and determining that the patient is in a resting state. The method further includes modifying the pacing rate of the IMD for N cardiac cycles in response to determining that the patient is in the resting state. N is an integer greater than 1. Modifying the pacing rate includes incrementally increasing the pacing rate for a first portion of the N cardiac cycles, and incrementally decreasing the pacing rate for a second portion of the N cardiac cycles. | 11-15-2012 |
20120290033 | TECHNIQUES FOR MODIFYING BREATHING RATE USING CARDIAC PACING - A method includes controlling a cardiac pacing rate of an implantable medical device to control a heart rate of a patient and detecting inhalation and exhalation of the patient. The method further includes determining that the patient is in a resting state, and, in response to determining that the patient is in the resting state, incrementally increasing the pacing rate while exhalation of the patient is detected and incrementally decreasing the pacing rate while inhalation of the patient is detected. | 11-15-2012 |
20130085399 | THERAPY CONTROL BASED ON NIGHTTIME CARDIOVASCULAR PRESSURE - Techniques for controlling therapy based on a physiological parameter indicative of ventricular filling pressure, such as various cardiovascular pressures, are described. One or more values of the physiological parameter that are collected during nighttime, or while the patient is otherwise asleep, inactive, or within a recumbent position, may be compared to one or more values of the physiological parameter collected during daytime, or while the patient is otherwise awake, active and/or upright. A therapy, such as for treating physiological factors that may lead to worsening HF, may be initiated or adjusted based on the comparison, e.g., if the nighttime values exceed the daytime values. | 04-04-2013 |