A cardiac rhythm management system provides an increase in pacing rate as a combination of responses to three characteristics of a relative-temperature signal: a dip, a positive slope, and a positive magnitude. The relative-temperature signal is the difference between a short-term and a long-term temperature average. A dip produces a limited and temporary rate increase having a first proportionality. A positive slope produces a rate increase with a second proportionality. A positive magnitude produces a rate increase with a third proportionality. The dip response seeds the slope response to provide a seamless and immediate rate transition after a dip. The cardiac rhythm management system limits and filters the sum of the rate increases to provide a sensor indicated rate, which is used to stimulate the heart.

Aspects of the present disclosure are directed toward a medical device having a a core assembly. The core assembly includes a core circuit assembly and a core assembly housing configured to enclose the core circuit assembly. The core assembly housing includes a first portion, and a second portion configured to be coupled to the first portion along a weld seam. The second portion includes at least one weld joint feature, which includes a thinned section of the second portion.

This document discusses, among other things, systems and methods for monitoring a patient at risk of epilepsy. A system comprises a sensor circuit that senses from the patient at least first and second physiological or functional signals. A wellness detector circuit can detect an epileptic event using the sensed physiological or functional signals, or additionally classify the epileptic event into one of epileptic seizure types. The system can generate a wellness indicator based on a trend of the physiological or functional signal during the detected epileptic event. The wellness indicator indicates an impact of the detected epileptic event on the health status of the patient. The system includes an output unit configured to output the detection of the epileptic event or the wellness indicator to a user or a process.

Systems and methods for ambulatory detection of medical events such as cardiac arrhythmia are described herein. An embodiment of an arrhythmia detection system may include a detection criterion circuit that determines a patient-specific detection criterion using a baseline cardiac characteristic when the patient is free of cardiac arrhythmias. The detection criterion circuit generates a patient-specific threshold of a signal metric by adjusting a population-based threshold of the signal metric, where the manner and the amount of adjustment is based on information about patient baseline cardiac characteristic. The arrhythmia detection system detects an arrhythmia episode using a physiologic signal sensed from the patient and the patient-specific arrhythmia detection threshold.

A system for application of neurostimulation includes an outer sheath, an elongate inner member in the outer sheath and movable relative to the outer sheath. The inner lumen has a distal end. An expandable member is coupled to the distal end of the inner member and is in the outer sheath. The expandable member is self-expanding upon from a compressed state in the outer sheath to an expanded state out of the outer sheath. The expandable member includes a distal portion including a plurality of wires woven together and a proximal portion including the plurality of wires extending parallel to a longitudinal axis. The system includes a plurality of electrode assemblies outward of the expandable member and circumferentially spaced around the expandable member. Each electrode assembly is coupled to two of the wires extending parallel to the longitudinal axis. Each electrode assembly includes a plurality of longitudinally-spaced electrodes.

Techniques for switching an implantable medical device (IMD) from a first mode to a second mode in relation to signals obtained from internal sensors are described. The internal sensors may include a temperature sensor and a biosensor. In some examples, processing circuitry of the IMD may make a first preliminary determination that the IMD is implanted based on a first signal from the temperature sensor. In response to the first preliminary determination being that the IMD is implanted, the processing circuitry may make a second preliminary determination that the IMD is implanted based on a second signal from the biosensor. The processing circuitry may switch the IMD from a first mode to a second mode based on both the first preliminary determination and the second preliminary determination being that the IMD is implanted.

Systems and methods for managing cardiac arrhythmias are discussed. A data management system receives a first detection algorithm including a detection criterion for detecting a cardiac arrhythmia. An arrhythmia detector detects arrhythmia episodes from a physiologic signal using a second detection algorithm that is different from and has a higher sensitivity for detecting the cardiac arrhythmia than the first detection algorithm. The arrhythmia detector assigns a detection indicator to each of the detected arrhythmia episodes. The detection indicator indicates a likelihood that the detected arrhythmia episode satisfies the detection criterion of the first detection algorithm. The system prioritizes the detected arrhythmia episodes according to the assigned detection indicators, and outputs the arrhythmia episodes to a user or a process according to the episode prioritization.

A medical device is configured to sense an acceleration signal and determine at least one frequency metric from the acceleration signal that is correlated to a frequency of oscillations of the acceleration signal. The medial device is configured to determine that the at least one frequency metric meets atrial tachyarrhythmia criteria and detect an atrial tachyarrhythmia in response to at least the frequency metric meeting the atrial tachyarrhythmia criteria.

A mechanism for transferring energy from an external power source to an implantable medical device is disclosed. A sensor may be used to measure a parameter that correlates to a temperature of the system that occurs during the transcutaneous coupling of energy. For example, the sensor may measure temperature of a surface of an antenna of the external power source. The measured parameter may then be compared to a programmable limit. A control circuit such as may be provided by the external power source may then control the temperature based on the comparison. The programmable limit may be, for example, under software control so that the temperature occurring during transcutaneous coupling of energy may be modified to fit then-current circumstances.

Certain embodiments of the present technology disclosed herein relate to implantable systems, and methods for use therewith, that use a temperature sensor to initially detect an onset of patient activity, and then use a motion sensor to confirm or reject the initial detection of the onset of patient activity. Other embodiments of the present technology disclosed herein relate to implantable systems, and methods for use therewith, that use a motion sensor to initially detect an onset of patient activity, and then use a temperature sensor to confirm or reject the initial detection of the onset of patient activity. The use of both a motion sensor and a temperature sensor provides improvements over using just one of the types of sensors for rate responsive pacing.