| Patent application number | Description | Published |
| 20080208020 | IMPLANTABLE TISSUE PERFUSION SENSING SYSTEM AND METHOD - A medical device for sensing cardiac events that includes a plurality of light sources capable of emitting light at a plurality of wavelengths, and a detector to detect the emitted light. A processor determines a plurality of light measurements in response to the emitted light detected by the detector, updates, for each of the plurality of wavelengths, a first normalization coefficient and a second normalization coefficient in response to the detected emitted light, and adjusts the determined plurality of light measurements in response to the first normalization coefficient and the second normalization coefficient. | 08-28-2008 |
| 20080208021 | IMPLANTABLE TISSUE PERFUSION SENSING SYSTEM AND METHOD - A medical device for sensing cardiac events that includes a plurality of electrodes sensing cardiac signals utilized to identify a cardiac event, a plurality of light sources capable of emitting light at a plurality of wavelengths, and a detector to detect the emitted light. A processor determines a plurality of light measurements in response to the emitted light detected by the detector, an isobestic blood volume index in response to determined light measurements of the plurality of light measurements from a first light source of the plurality of light sources emitting light at an isobestic wavelength, determines an oxygen index associated with light measurements of the plurality of light measurements from a light source of the plurality of light sources other than the first light source, and verifies the identifying of the cardiac event in response to the determined isobestic blood volume index and the determined oxygen index. | 08-28-2008 |
| 20080208066 | IMPLANTABLE TISSUE PERFUSION SENSING SYSTEM AND METHOD - A medical device for sensing cardiac events that includes a plurality of light sources capable of emitting light at a plurality of wavelengths, and a detector to detect the emitted light. A processor generates an ambient light measurement in response to ambient light detected by the detector, generates a plurality of light measurements in response to the emitted light detected by the detector, and adjusts the plurality of light measurements in response to the ambient light measurement. | 08-28-2008 |
| 20080208067 | IMPLANTABLE TISSUE PERFUSION SENSING SYSTEM AND METHOD - A medical device for sensing cardiac events that includes a plurality of electrodes sensing cardiac signals utilized to identify a cardiac event, a plurality of light sources capable of emitting light at a plurality of wavelengths, and a detector to detect the emitted light. A processor determines a plurality of light measurements in response to the emitted light detected by the detector, and generates a blood volume index in response to a light source of the plurality of light sources emitting light at an isobestic wavelength. The blood volume index is then utilized to verify the identifying of the cardiac event. | 08-28-2008 |
| 20080208269 | IMPLANTABLE TISSUE PERFUSION SENSING SYSTEM AND METHOD - A medical device system for sensing cardiac events that includes a plurality of electrodes sensing cardiac signals utilized to identify a cardiac event, a plurality of light sources capable of emitting light at a plurality of wavelengths, and a detector to detect the emitted light. A processor determines a plurality of light measurements in response to the emitted light detected by the detector, determines changes in perfusion in response to first changes in the plurality of light measurements in a direction indicative of a decrease in blood oxygenation and second changes in a direction indicative of a decrease in blood volume, and adjusts delivery of therapy by the device in response to the determined loss of perfusion. | 08-28-2008 |
| 20080228094 | Heart Monitoring Systems, Apparatus and Methods Adapted to Detect Myocardial Ischemia - Embodiments include heart monitoring systems, apparatus, and methods adapted to detect myocardial ischemia. An apparatus includes at least one first-tier sensor/analyzer adapted to sense a first input related to cardiac function, and to produce a first-tier trigger signal when the first input indicates myocardial ischemia. In an embodiment, a first-tier sensor/analyzer includes an ECG sensor/analyzer. In another embodiment, a first-tier sensor/analyzer includes a patient activator. An apparatus further includes at least one second-tier sensor/analyzer adapted to sense a second input related to cardiac function, and to produce a second-tier trigger signal when the second input indicates myocardial ischemia. In an embodiment, a second-tier sensor-analyzer includes a heart sound sensor/analyzer. A triggering element is adapted to produce a response-invoking signal in response to the first-tier trigger signal and the second-tier trigger signal. The response-invoking signal may invoke a patient alert, a message to an external system, and/or a cardiac stimulus. | 09-18-2008 |
| 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 |
| 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 |
| 20100317937 | Device and Method for Monitoring of Absolute Oxygen Saturation and Total Hemoglobin Concentration - A medical device for monitoring of oxygen saturation includes an optical sensor adapted for positioning adjacent to a tissue volume. The optical sensor has a light emitting portion capable of emitting light at a plurality of wavelengths and a light detecting portion capable of generating an electrical output signal corresponding to light incident on the detecting portion. A control module coupled to the optical sensor controls the light emitted by the light emitting portion. A monitoring module receives the output signal from the light detecting portion and computes a volume-independent measure of oxygen saturation in the volume of tissue using the output signal. | 12-16-2010 |
| 20100317938 | Device and Method for Monitoring of Absolute Oxygen Saturation and Tissue Hemoglobin Concentration - A method and medical device for detecting signals that detects emitted light scattered by a volume of tissue delivered along a first pathway at a plurality of wavelengths to generate corresponding first detected light intensity output signals, detects emitted light scattered by the volume of tissue delivered along a second pathway different from the first pathway at a plurality of wavelengths to generate corresponding second detected light intensity output signals, determines whether a difference between the emitted light detected along the first pathway and the emitted light detected along the second pathway is greater than a predetermined threshold, and alters sensing by the device in response to the determining whether a difference is greater than the predetermined threshold. | 12-16-2010 |
| 20100317939 | Device and Method for Monitoring of Absolute Oxygen Saturation and Tissue Hemoglobin Concentration - A method and medical device for detecting signals that detects emitted light scattered by a volume of tissue delivered along a first pathway and a second pathway different from the first pathway, detects emitted light scattered by a volume of tissue delivered along a third pathway and a fourth pathway different from the third pathway, determines a first uniformity corresponding to the emitted light detected along the first pathway and the second pathway, determines a second uniformity corresponding to the emitted light detected along third pathway and the fourth pathway, determines a total uniformity in response to the determined first uniformity and the determined second uniformity, and alters sensing by the device in response to the determined total uniformity. | 12-16-2010 |
| 20100317942 | Tissue Oxygenation Monitoring in Heart Failure - A medical device system and associated method are used for monitoring a heart failure patient. A medical device for monitoring delivery of a therapy includes a sensor sensing an optical sensor signal corresponding to light attenuation by a volume of body tissue of a patient, a therapy delivery module to deliver a therapy, and a processor configured to compute a first tissue oxygenation measurement from the optical sensor signal prior to initiating delivery of the therapy, compute a second tissue oxygenation measurement from the optical sensor signal subsequent to initiating delivery of the therapy, compare the first and the second tissue oxygenation measurements, and determine whether the delivered therapy was successful in response to the first tissue oxygenation measurement and the second tissue oxygenation measurement. | 12-16-2010 |
| 20100317946 | Shock Reduction Using Absolute Calibrated Tissue Oxygen Saturation and Total Hemoglobin Volume Fraction - An implantable medical device for detecting and treating an arrhythmia includes an optical sensor adapted for positioning adjacent to a blood-perfused tissue volume. In one embodiment for controlling arrhythmia therapies delivered by the device, the optical sensor is controlled to emit light in response to detecting an arrhythmia, detect light scattered by the volume of blood perfused tissue including measuring an optical sensor output signal corresponding to the intensity of scattered light for at least four spaced-apart wavelengths, and compute a volume-independent measure of tissue oxygen saturation from the detected light. The hemodynamic status of the arrhythmia is detected in response to the measure of tissue oxygen saturation. | 12-16-2010 |
| 20100317947 | Tissue Oxygenation Monitoring in Heart Failure - A medical device system and associated method control the delivery of a therapy to a patient. The system includes an activity sensor and detects a change in activity level of the patient. The system further include an optical sensor to sense signal corresponding to tissue light attenuation. The system computes a tissue oxygenation measurement in response to detecting a change in activity level. A parameter controlling delivery of the therapy is adjusted in response to detecting the decreased tissue oxygenation. | 12-16-2010 |
| 20100318146 | Tissue Oxygenation Monitoring in Heart Failure - A medical device for monitoring delivery of a therapy that includes a therapy delivery module to deliver a therapy, a controller to set a therapy delivery control parameter, an optical sensor to produce a signal corresponding to tissue light attenuation, and a processor configured to compute a tissue oxygenation measurement from the optical sensor signal, wherein the controller, the optical sensor, and the processor operate cooperatively to determine a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation. | 12-16-2010 |
| 20100318149 | Shock Reduction Using Absolute Calibrated Tissue Oxygen Saturation and Total Hemoglobin Volume Fraction - An implantable medical device that includes an optical sensor for providing a signal corresponding to light attenuation by a volume of blood perfused tissue, a control module coupled to the optical sensor controlling the light emitted by the optical sensor, a monitoring module receiving an optical sensor output signal and measuring light attenuation, a tissue electrode for stimulating the volume of blood perfused tissue, a pulse generator coupled to the tissue electrode for delivering electrical stimulation to the volume of blood-perfused tissue, and a processor coupled to the cardiac electrode and the monitoring module and configured to detect an arrhythmia in response to the depolarization signals, compute a tissue oxygenation measurement and control the pulse generator to deliver electrical stimulation to the volume of blood-perfused tissue in response to detecting the arrhythmia, and detect a hemodynamic status of the arrhythmia in response to at least one of a detected rate of tissue oxygenation decline and a detected rate of tissue oxygenation recovery. | 12-16-2010 |