Abstract: This disclosure describes techniques for configuring an IMD into the exposure operating mode. Prior to a medical procedure that generates a disruptive energy field, such as an MRI scan, an electronic prescription is configured to indicate that the IMD is authorized for the medical procedure that includes a disruptive energy field. The electronic prescription includes one or more designated bits within a storage element of the IMD. When the patient in which the IMD is implanted arrives for the medical procedure, a user (such as an MRI operator) interacts with a telemetry device to determine whether the electronic prescription is configured. Upon determining that the electronic prescription is configured, the IMD transitions into the exposure operating mode designed for operation in the disruptive energy field. In this manner, the electronic prescription confirms to the user that that the IMD has been checked for suitability for operation during the medical procedure.

Abstract: The present invention provides a packaging technique and apparatus that incorporates a flexible substrate package with a three-axis magnetic sensor for three-axis sensing in an implantable medical device. The apparatus includes three single-axis magnetic sensor integrated circuits (ICs) that are mounted to a substrate and encapsulated with a polymer mold compound. The substrate is excised around each of the sensor ICs to form panels that are folded to align the three single-axis sensors in the x, y and z axis.

Abstract: This disclosure describes techniques for configuring an IMD into the exposure operating mode. Prior to a medical procedure that generates a disruptive energy field, such as an MRI scan, an electronic prescription is configured to indicate that the IMD is authorized for the medical procedure that includes a disruptive energy field. The electronic prescription includes one or more designated bits within a storage element of the IMD. When the patient in which the IMD is implanted arrives for the medical procedure, a user (such as an MRI operator) interacts with a telemetry device to determine whether the electronic prescription is configured. Upon determining that the electronic prescription is configured, the IMD transitions into the exposure operating mode designed for operation in the disruptive energy field. In this manner, the electronic prescription confirms to the user that that the IMD has been checked for suitability for operation during the medical procedure.

Abstract: This disclosure describes techniques for configuring an IMD into the exposure operating mode. Prior to a medical procedure that generates a disruptive energy field, such as an MRI scan, an electronic prescription is configured to indicate that the IMD is authorized for the medical procedure that includes a disruptive energy field. The electronic prescription includes one or more designated bits within a storage element of the IMD. When the patient in which the IMD is implanted arrives for the medical procedure, a user (such as an MRI operator) interacts with a telemetry device to determine whether the electronic prescription is configured. Upon determining that the electronic prescription is configured, the IMD transitions into the exposure operating mode designed for operation in the disruptive energy field. In this manner, the electronic prescription confirms to the user that that the IMD has been checked for suitability for operation during the medical procedure.

Abstract: In an implantable medical device having an electrical lead coupled to tissue of a user and a circuit for measuring the impedance of the lead, a method and apparatus for responding to impedance variations in the lead which includes measuring the impedance of the lead while monitoring physiologic parameters of the user, detecting the presence or absence of electromagnetic interference, and if the impedance of the lead is out-of-range, determining whether the electromagnetic interference exceeds a predetermined value, and if the electromagnetic interference exceeds a predetermined value, administering a therapy to the tissue of the user.

Abstract: An electrical medical lead is provided having two or more electrodes, electrically insulated from each other and electrically coupled to individually insulated filars in a multi-filar coiled conductor. When the lead is used with a medical device equipped with a switch matrix, electrodes are selected individually or simultaneously to serve as an anode or cathode in any unipolar, bipolar or multi-polar configuration for delivering stimulation and/or sensing signals in excitable tissue. In one embodiment, a tip electrode array is expandable for improving electrode contact with targeted tissue and stabilizing lead position.

Abstract: In an implantable medical device having an electrical lead coupled to tissue of a user and a circuit for measuring the impedance of the lead, a method and apparatus for responding to impedance variations in the lead which includes measuring the impedance of the lead while monitoring physiologic parameters of the user, detecting the presence or absence of electromagnetic interference, and if the impedance of the lead is out-of-range, determining whether the electromagnetic interference exceeds a predetermined value, and if the electromagnetic interference exceeds a predetermined value, administering a therapy to the tissue of the user.

Abstract: An electrical medical lead is provided having two or more electrodes, electrically insulated from each other and electrically coupled to individually insulated filars in a multi-filar coiled conductor. When the lead is used with a medical device equipped with a switch matrix, electrodes are selected individually or simultaneously to serve as an anode or cathode in any unipolar, bipolar or multi-polar configuration for delivering stimulation and/or sensing signals in excitable tissue. In one embodiment, a tip electrode array is expandable for improving electrode contact with targeted tissue and stabilizing lead position.

Abstract: In a pacemaker, a method and apparatus for providing rate response in proportion to the patient's metabolic demand for cardiac output as determined in response to the patient's breathing rate or respiratory minute ventilation or contraction strength, optionally augmented by the patient's activity level. An implantable pulse generator (IPG) has one or more pacing leads having a proximal end coupled to the IPG and a distal end in contact with a patient's heart. A pressure wave transducer mounted in the IPG in relation to the proximal end of the pacing lead senses pressure waves transmitted from the distal end of the pacing lead to the proximal end thereof. The pressure waves originate from disturbances imparted to the lead by heart contractions and breathing. A further isolated, reference sensor is also incorporated into the IPG in a similar fashion. An activity signal processor is coupled to the pressure wave or reference sensor for providing a patient activity physiologic signal.

Abstract: In an implanted medical device, a method and apparatus for detecting pressure waves caused by movement of a body organ, muscle group, limb or the like and transmitted through a catheter or lead body to the implanted medical device employing a pressure wave transducer mounted in relation to the proximal end of the catheter or lead to detect the transmitted pressure waves. The system may also include a reference transducer having the same pressure wave response characteristics as the pressure wave transducer but isolated from the proximal connector end for providing a reference signal including common mode pressure wave noise that both transducers are simultaneously subjected to. The pressure wave signal and the reference signal are preferably amplified, bandpass filtered to the body pressure wave of interest and stored, telemetered out or used to trigger a device operation.

Abstract: A capture verification system for a cardiac pacemaker comprising an implantable pulse generator (IPG) and one or more pacing leads having a proximal end coupled to the IPG and a distal end in contact with a patient's heart. The capture verification system employs a pressure wave sensor mounted in the IPG in relation to the proximal end of the pacing lead for sensing pressure waves transmitted from the distal end of the pacing lead to the proximal end thereof. The pressure waves include characteristic sounds of heart contraction and/or distal end lead motion caused by the contraction motion of the patient's heart that are transmitted along the lead body to the active sensor. A further isolated, reference sensor is also incorporated into the IPG in a similar fashion. Signal processors are coupled to the pressure wave and reference sensors for nulling out common mode noise.

Abstract: A method and apparatus for selectively controlling an oscillator-driven implantable stimulator to operate either in a quiescent state, in response to a command from an external communicating device, or in an active state in response either to removal of an activation pin or to an activating command from an external communicating device. Upon completion of manufacture of the stimulator, and before being placed on a shelf to await implantation in a patient, the activation pin is inserted into the stimulator and the external communicating device is triggered to send a deactivating command to the stimulator. The stimulator responds by generally disabling current sources to stimulator circuits, while maintaining current sources to a wake up circuit of the stimulator that is associated with communication operations. The stimulator is activated by subsequently transmitting an activating command from an external communicating device to the implantable stimulator, or by removing the activation pin.