A system that provides the ability to integrate both diagnostic tissue detection and therapeutic tissue treatment functionality in an implantable medical device (IMD), such as a graft or stent. The system comprises: an IMD having a pair of electrodes configured to contact biological tissue at an implant location; an impedance sensor configured to detect data indicative of a complex impedance of the biological tissue at the electrodes for a plurality of frequencies; and an analysis device configured to determine one or more cell types in the biological tissue using information indicative of variation in phase and magnitude of the complex impedance across the plurality of frequencies. The system may include a signal generator for applying a treatment signal to the same electrodes.

A system that provides the ability to integrate both diagnostic tissue detection and therapeutic tissue treatment functionality in an implantable medical device (IMD), such as a graft or stent. The system comprises: an IMD having a pair of electrodes configured to contact biological tissue at an implant location; an impedance sensor configured to detect data indicative of a complex impedance of the biological tissue at the electrodes for a plurality of frequencies; and an analysis device configured to determine one or more cell types in the biological tissue using information indicative of variation in phase and magnitude of the complex impedance across the plurality of frequencies. The system may include a signal generator for applying a treatment signal to the same electrodes.

The disclosed technology includes a medical probe comprising a tubular shaft extending along a longitudinal axis and including a proximal end and a distal end. The medical probe further comprises an expandable basket assembly proximate the distal end of the tubular shaft. The basket assembly comprises a plurality of C-shaped spines and one or more electrodes coupled to each of the spines, each electrode defining a lumen through the electrode so that a spine extends through the lumen of each of the one or more electrodes. The spines converge at a central spine intersection at a distal end of the basket assembly. Each spine comprises a respective end connected to the distal end of the tubular shaft.

The present disclosure is directed to a system and method for measuring impedance across a plurality of electrodes and assessing proximity or contact between electrodes of a medical device and patient tissue. In one embodiment, contact is assessed individual electrodes and cardiac tissue using bipolar electrode complex impedance measurements. Initially, baseline impedance values are established for each of the individual electrodes based on the responses of the electrodes to the applied drive signals. After establishing the baseline impedance values a series of subsequent impedance values are measured for each electrode. For each electrode, each subsequent impedance value may be compared to a previous baseline impedance value for that electrode. If a subsequent impedance value is less than the baseline impedance value for a given electrode, the baseline impedance value may be reset to the subsequent impedance value. Such systems and method are particularly applicable to medical devices having numerous electrodes.

The present disclosure is directed to a system and method for measuring impedance across a plurality of electrodes and assessing proximity or contact between electrodes of a medical device and patient tissue. In one embodiment, contact is assessed individual electrodes and cardiac tissue using bipolar electrode complex impedance measurements. Initially, baseline impedance values are established for each of the individual electrodes based on the responses of the electrodes to the applied drive signals. After establishing the baseline impedance values a series of subsequent impedance values are measured for each electrode. For each electrode, each subsequent impedance value may be compared to a previous baseline impedance value for that electrode. If a subsequent impedance value is less than the baseline impedance value for a given electrode, the baseline impedance value may be reset to the subsequent impedance value. Such systems and method are particularly applicable to medical devices having numerous electrodes.

In some examples, a device includes a catheter insert elongated body defining a body lumen, the catheter insert elongated body being configured to be at least partially inserted to a catheter lumen defined by a catheter without covering a first fluid opening of the catheter and to form a fluidically tight coupling with the catheter, and one or more sensors positioned on the elongated body. At least one of the one or more sensors are configured to sense a substance of interest. The catheter insert elongated body includes a material that is a substantially non-permeable to the substance of interest.

In some examples, a device includes a catheter insert elongated body defining a body lumen, the catheter insert elongated body being configured to be at least partially inserted to a catheter lumen defined by a catheter without covering a first fluid opening of the catheter and to form a fluidically tight coupling with the catheter, and one or more sensors positioned on the elongated body. At least one of the one or more sensors are configured to sense a substance of interest. The catheter insert elongated body includes a material that is a substantially non-permeable to the substance of interest.

Devices, systems, and techniques are described to detect when a power transmitting and receiving system is in an inefficient position, which may cause a thermal response that less desirable than a more efficient position. The system may power transmitting device configured to wirelessly transfer electromagnetic energy to a power receiving device. Processing circuitry of the system may compute a target output power deliverable by the power transmitting device for a first duration and control the power transmitting device to output the target output power based in part on a heat limit. The processing circuitry may further calculate an energy transfer efficiency to the power receiving unit, update an adjustment factor based on the calculated energy transfer efficiency, and apply the adjustment factor to the heat limit for a subsequent duration.

A method for converting physiological signals includes: obtaining a first signal as a function of a time parameter, wherein the first signal represents electrocardiogram data; obtaining a second signal as a function of the time parameter, wherein the second signal represents physiological data different from the electrocardiogram data; mixing the first signal and the second signal to obtain a mixed signal; and generating a frequency spectrum pertaining to the mixed signal.

Devices, systems, and techniques are disclosed for determining spatial relationships between electrodes implanted within a patient. In one example, a medical device delivers, via a first electrode, an electrical stimulus and senses, for each other electrode, a respective electrical signal indicative of the electrical stimulus. The medical device determines, for each other electrode, a respective value for each respective electrical signal. The medical device determines, based on the respective values for each respective electrical signal and values of tissue conductivity of tissues of the patient interposed between the first electrode and the other electrodes, spatial relationships between the first electrode and each other electrode of the plurality of electrodes.