Abstract: A fixation member component, for example, employed by a relatively compact implantable medical device, includes a plurality of fingers; each finger includes a first segment extending from a fixed end of the corresponding finger, and a second segment extending from the corresponding first segment to a free end of the corresponding finger. Each first segment is elastically deformable from a relaxed to an extended condition, and from the relaxed to a compressed condition, and includes a peripheral portion and a central cut-out portion, framed by the peripheral portion. In the compressed condition, a free tip of the cut-out portion of some or all of the fingers may lodge against opposing tissue surfaces, via a spring force of the compressed fingers. Each second segment and cut-out portion is preferably configured to prevent penetration thereof within tissue at the implant site.

Abstract: A medical device system is configured to sense physiological events by a first device and control a transducer to emit trigger signals in response to the sensed physiological events. A second device detects the trigger signals and delivers therapeutic stimulation pulses in response to the trigger signals. The therapeutic stimulation pulses have a combined total time duration over the sensed physiological events that is greater than the combined total time duration of the trigger signals.

Abstract: A tine portion for an implantable medical device includes a hook segment and a distal segment terminated by a tissue-piercing tip, wherein the distal segment extends from the hook segment to the tip. The hook segment, which is elastically deformable from a pre-set curvature, has one of: a round cross-section and an elliptical cross-section, while the distal segment has a flattened, or approximately rectangular cross-section. One or a pair of the tine portions may be integrally formed, with a base portion, from a superelastic wire, wherein the base portion is configured to fixedly attach to the device, for example, being captured between insulative members of a fixation subassembly.

Abstract: A medical device system is configured to sense a physiological signal by a first device and generate a control signal by the first device in response to the physiological signal. An acoustical emitting device is controlled by the first device to emit an acoustical trigger signal in response to the control signal. A second device detects the acoustical trigger signal and delivers an automatic therapy to a patient in response to detecting the acoustical trigger signal.

Abstract: A tine portion of an implantable medical device includes a hook segment and a distal segment extending therefrom, wherein the hook segment is pre-set to extend along a curvature and is elastically deformable therefrom to an open position. The distal segment includes a tooth and an end that surrounds the tooth, wherein the end includes a pair of legs and a distal arch. The legs extend along a length of, and on opposing sides of the tooth, and the distal arch extends between the legs, distal to a tissue-piercing tip of the tooth. When the hook segment is in the open position, and a force is applied along a longitudinal axis of the device, to push the distal arch of the distal segment against tissue, for initial tissue penetration, the legs of the end of the distal segment bend in elastic deformation to expose the tissue-piercing tip to the tissue.

Abstract: A fixation member component, for example, employed by a relatively compact implantable medical device, includes a plurality of fingers; each finger includes a first segment extending from a fixed end of the corresponding finger, and a second segment extending from the corresponding first segment to a free end of the corresponding finger. Each first segment is elastically deformable from a relaxed to an extended condition, and from the relaxed to a compressed condition, and includes a peripheral portion and a central cut-out portion, framed by the peripheral portion. In the compressed condition, a free tip of the cut-out portion of some or all of the fingers may lodge against opposing tissue surfaces, via a spring force of the compressed fingers. Each second segment and cut-out portion is preferably configured to prevent penetration thereof within tissue at the implant site.

Abstract: A tine portion of an implantable medical device includes a hook segment and a distal segment extending therefrom, wherein the hook segment is pre-set to extend along a curvature and is elastically deformable therefrom to an open position. The distal segment includes a tooth and an end that surrounds the tooth, wherein the end includes a pair of legs and a distal arch. The legs extend along a length of, and on opposing sides of the tooth, and the distal arch extends between the legs, distal to a tissue-piercing tip of the tooth. When the hook segment is in the open position, and a force is applied along a longitudinal axis of the device, to push the distal arch of the distal segment against tissue, for initial tissue penetration, the legs of the end of the distal segment bend in elastic deformation to expose the tissue-piercing tip to the tissue.

Abstract: A tine portion for an implantable medical device includes a hook segment and a distal segment terminated by a tissue-piercing tip, wherein the distal segment extends from the hook segment to the tip. The hook segment, which is elastically deformable from a pre-set curvature, has one of: a round cross-section and an elliptical cross-section, while the distal segment has a flattened, or approximately rectangular cross-section. One or a pair of the tine portions may be integrally formed, with a base portion, from a superelastic wire, wherein the base portion is configured to fixedly attach to the device, for example, being captured between insulative members of a fixation subassembly.

Abstract: A medical device system is configured to sense a physiological signal by a first device and generate a control signal by the first device in response to the physiological signal. An optical transducer is controlled by the first device to emit an optical trigger signal in response to the control signal. A second device receives the optical trigger signal and delivers an automatic therapy to a patient in response to detecting the optical trigger signal.

Abstract: A medical device system is configured to sense physiological events by a first device and control a transducer to emit trigger signals in response to the sensed physiological events. A second device detects the trigger signals and delivers therapeutic stimulation pulses in response to the trigger signals. The therapeutic stimulation pulses have a combined total time duration over the sensed physiological events that is greater than the combined total time duration of the trigger signals.

Abstract: A medical device system is configured to sense a physiological signal by a first device and generate a control signal by the first device in response to the physiological signal. An acoustical emitting device is controlled by the first device to emit an acoustical trigger signal in response to the control signal. A second device detects the acoustical trigger signal and delivers an automatic therapy to a patient in response to detecting the acoustical trigger signal.

Abstract: A tine portion of an implantable medical device includes a hook segment and a distal segment extending therefrom, wherein the hook segment is pre-set to extend along a curvature and is elastically deformable therefrom to an open position. The distal segment includes a tooth and an end that surrounds the tooth, wherein the end includes a pair of legs and a distal arch. The legs extend along a length of, and on opposing sides of the tooth, and the distal arch extends between the legs, distal to a tissue-piercing tip of the tooth. When the hook segment is in the open position, and a force is applied along a longitudinal axis of the device, to push the distal arch of the distal segment against tissue, for initial tissue penetration, the legs of the end of the distal segment bend in elastic deformation to expose the tissue-piercing tip to the tissue.

Abstract: 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.

Abstract: A tine portion for an implantable medical device includes a hook segment and a distal segment terminated by a tissue-piercing tip, wherein the distal segment extends from the hook segment to the tip. The hook segment, which is elastically deformable from a pre-set curvature, has one of: a round cross-section and an elliptical cross-section, while the distal segment has a flattened, or approximately rectangular cross-section. One or a pair of the tine portions may be integrally formed, with a base portion, from a superelastic wire, wherein the base portion is configured to fixedly attach to the device, for example, being captured between insulative members of a fixation subassembly.

Abstract: 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.

Abstract: A system and method for identifying the location of a medical device within a patient's body may be used to localize the fossa ovalis for trans-septal procedures. The systems and methods measure light reflected by tissues encountered by an optical array. An optical array detects characteristic wavelengths of tissues that are different distances from the optical array. The reflectance of different wavelengths of light at different distances from an optical array may be used to identify the types of tissue encountered, including oxygenated blood in the left atrium as detected from the right atrium through the fossa ovalis.

Abstract: A method and device for delivering therapy that includes an electrode to sense cardiac signals and to deliver a therapy, a monitoring module detecting a cardiac event in response to the sensed cardiac signals using first detection criteria, a sensor emitting light and detecting emitted light scattered by a tissue volume adjacent the sensor to generate a corresponding detected light intensity output signal, a control module coupled to the sensor to control light emission of the sensor in response to delivering the therapy, and a controller coupled to the monitoring module, the therapy delivery module and the sensor, the controller configured to determine tissue oxygenation measurements in response to the output signal, determine a tissue oxygenation trend in response to the tissue oxygenation measurements, determine a recovery index in response to the determined tissue oxygenation trend, and control one or both of detecting a cardiac event by the monitoring module and delivery of therapy by the therapy deliver

Abstract: A method for using a medical device comprising an optical sensor to measure calibrated oxygen saturation in a body tissue uses a standard spectral response of blood established for multiple of oxygen saturations and a standard spectral response of a reference material. The standard responses are established using a spectrometer. The spectral power output of the optical sensor is measured using a spectrometer. The optical sensor output signal response to the reference material is obtained. A processor computes a device-specific calibration curve for the medical device using the measured spectral power output and the standard spectral response of blood and computes an optical gain using the standard spectral response of the reference material and the measured spectral power output of the optical sensor. The device-specific calibration curve and optical gain of the optical sensor are stored in a memory of the medical device.

Abstract: An implantable medical sensor system provides signals representative of a magnitude of moment fraction applied to a sensor module at a selected site. A sensor module includes a first transducer producing a first signal having an associated first response to pressure and strain applied to the sensor module and a second transducer producing a second signal having an associated second response to pressure and strain applied to the sensor module. A moment fraction is computed in response to the first signal and the second signal. In various embodiments, the moment fraction is used to guide positioning of the sensor module, indicate a need for repositioning the sensor module, report loading of the sensor module during normal operation for use as sensor design information and in setting sensor calibration ranges.

Abstract: 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.