Abstract: Systems, methods, and devices for activating an implantable medical device from a low-power sleep state are provided. One method includes receiving a wake-up signal at a receiver device from a transmitter device. The wake-up signal includes a series of pulses having a pulse pattern encoding a predetermined wake-up code. The wake-up signal is transmitted via intracorporeal communication of electrical pulses conducted by interstitial tissues of a patient's body. The method further includes extracting the wake-up code from the wake-up signal and determining whether the wake-up code corresponds to a stored wake-up value. The method further includes, in response to determining that the predetermined wake-up code corresponds to the stored wake-up value, switching at least one active circuit element of the receiver device from a lower-power sleep state into a higher-power operational state.

Abstract: A lead for an implantable cardiac prosthesis having an integrated protection against the effects of magnetic resonance imaging (“MRI”) fields. A protection circuit (26) may be placed at the distal end of the lead comprises a resistive component (28) interposed between the electrode (E1, E2) and the distal end of the conductor (22, 24) associated with this electrode. A normally-open controlled active switch (34, 36) may allow in its closed state to short-circuit the resistive component. A control stage (32) may be coupled to the conductors and detect the voltage of a stimulation pulse applied on the conductor(s), and selectively control by this voltage the closing of the active switch for a duration at least equal to the duration of detected stimulation pulse.

Abstract: A method for use by an active medical device includes using a stimulation device and an endocardial acceleration sensor to obtain a plurality of hemodynamic parameters associated with at least three atrioventricular delays. The method further includes using the plurality of hemodynamic parameters to find a second derivative associated with the atrioventricular delays. The method further includes using interpolation to estimate an atrioventricular delay which will reduce the second derivative associated with the atrioventricular delays. The method further includes using the estimated atrioventricular delay in a subsequent stimulation.

Abstract: An autonomous active medical implantable device, with a power supply and a wake-up circuit that responds to receipt of specific pulses transmitted through the interstitial tissues of the body. A transmitter device (40) generates trains of modulated pulses applied to electrodes (22, 24), and a receiver (50) processes (e.g., filter, amplify and demodulate) pulses collected on electrodes (22?, 24?). The receiver circuits (50) are selectively activated from a dormant (sleep) state in which they are not powered by a power source (34), to an operational (active) state in which they are powered and able to process (e.g., filter, amplify and demodulate) the collected pulses. A specific wake-up pulse train, configured in a predetermined characteristic pulse pattern, triggers passive wake-up circuits (66) in the receiver (50) to switch the receiver circuits from the sleep state to the operational state.

Abstract: A intracorporeal medical capsule is shown and described. The capsule includes an elastically deformable base having an anchor at one end and coupled to a capsule body at the opposite end. An energy harvesting element is elastically coupled to a seismic mass within the capsule body. The elastically deformable base increases energy harvested at the energy harvesting element due to elastic movement of the capsule body in the presence of blood flow around the capsule body.

Abstract: An active medical device using non-linear filtering for the reconstruction of a surface electrocardiogram (ECG) from an endocardial electrogram (EGM) is disclosed. The device for the reconstruction of the surface ECG comprises: a plurality of inputs, receiving a corresponding plurality of EGM signals from endocardial or epicardial electrogram (x1[n], x2[n]), each collected on a respective EGM derivation of a plurality of EGM derivations, and at least one output delivering a reconstructed surface ECG electrocardiogram signal (y[n]), related to an ECG derivation, and a non-linear digital filter (12?, 12?, 14) with a transfer function that determines the reconstructed ECG signal based on said plurality of input EGM signals. The non-linear digital filter includes a Volterra filter type (12, 12?, 12?) whose transfer function includes a linear term (h1) and at least one quadratic (h2) and/or cubic (h3) term(s).

Abstract: A lead for an implantable cardiac prosthesis, having an integrated protection against the effects of magnetic resonance imaging (“MRI”) fields. A protection circuit (26), placed at the distal end of the lead comprises a resistive component (28) interposed between the electrode (E1, E2) and the distal end of the conductor (22, 24) associated with this electrode. A normally-open controlled active switch (34, 36), allows in its closed state to short-circuit the resistive component. A control stage (32) is coupled to the conductors and detects the voltage of a stimulation pulse applied on the conductor(s), and selectively controls by this voltage the closing of the active switch for a duration at least equal to the duration of detected stimulation pulse.

Abstract: An active medical device such as pacemaker, defibrillator and/or resynchronizer with automatic optimization of atrioventricular delay is disclosed. The active medical device is adapted for analyzing a signal delivered by a hemodynamic sensor such as an endocardial acceleration sensor, whose variation according to the AVD is represented by a sigmoid function. An optimal AVD is searched by: applying a reference AVD (XC), at least one left AVD (XL, XLL) and at least one right AVD (XR, XRR); measuring the corresponding hemodynamic parameters (Y1, Y2, Y3, Y4, Y5); evaluating the second derivative of the function at the respective points (XC, Y3; XL, Y2, XR, Y4) of the characteristic corresponding to the reference AVD, to the left AVD and to the right AVD; estimating from these values of second derivatives, the position of an intermediate point of the characteristic for which the second derivative is zero or minimum, and determining the corresponding AVD for that intermediate point as the optimal AVD.

Abstract: An active implantable medical device for cardiac resynchronization with automatic and almost in real time optimization of the interventricular and atrio-ventricular delays is disclosed. The active implantable medical device includes a closed-loop for continuously controlling the atrio-ventricular delay AVD and the inter-ventricular delay VVD according to a hemodynamic signal delivered by a hemodynamic sensor. The closed-loop provides controlled modulation (38) and demodulation (42) the AVD, and modulation (48) and demodulation (52) the VVD, the modulation and demodulation being functionally interdependent (54, 56) by a sequence of alternating operation. A closed-loop regulator (36) for controlling the AVD receives as input an error signal (EAVD) delivered based on demodulating the AVD (42) and outputs an AVD signal. A closed-loop regulator (46) for controlling the VVD receives as input a signal error (EVVD) based on demodulating the DVV and outputs a VVD signal.

Abstract: Reconstruction of a surface electrocardiogram from far field signals extracted from an endocardial electrogram in an active medical device is disclosed. The device collects a ventricular EGM signal (EGMV) and an atrial EGM signal (EGMA), and extracts a ventricular far field signal component (FFV) and an atrial far field signal component (FFA). The ventricular and atrial far field signal components are combined to deliver as an output a reconstructed surface electrogram ECG signal (ECGj*). The ventricular and atrial far field signals are respectively extracted from the collected ventricular and atrial EGM signals (FFV, FFA). The reconstruction of the ECG is operated by ventricular (18) and atrial (16) far field signal estimator filters. According to one embodiment, the far field signal estimator filters are linear or nonlinear filters, receiving as input the far field signal components. An adder (20) adds the filtered signals and delivers as output the reconstructed ECG signal (ECGj*).

Abstract: An RF telemetry receiver circuit for active implantable medical devices. The baseband binary signal (Db) is doubly modulated by a low frequency carrier (Fm) and by a high frequency carrier (Fc). The receiver circuit is a semi-passive non heterodyne circuit, devoid of a local oscillator and mixer. It comprises an antenna (104), a passive bandpass filter (108) centered on the high-frequency carrier (Fc), a passive envelope detector (120-126) and a, digital demodulator (116). The envelope detector comprises a first diode circuit (120) of non-coherent detection, an active bandpass filter (122) centered on a frequency (2.Fm) twice the low frequency carrier and having a bandwidth (2.Db) twice the baseband bandwidth, and a second diode circuit (124) of non-coherent detection, outputting a baseband signal applied to the digital demodulation stage (116).

Abstract: A lead for an implantable cardiac prosthesis, having an integrated protection against the effects of magnetic resonance imaging (“MRI”) fields. A protection circuit (26), placed at the distal end of the lead comprises a resistive component (28) interposed between the electrode (E1, E2) and the distal end of the conductor (22, 24) associated with this electrode. A normally-open controlled active switch (34, 36), allows in its closed state to short-circuit the resistive component. A control stage. (32) is coupled to the conductors and detects the voltage of a stimulation pulse applied on the conductor(s), and selectively controls by this voltage the closing of the active switch for a duration at least equal to the duration of detected stimulation pulse.

Abstract: An autonomous active medical implantable device, with a power supply and a wake-up circuit that responds to receipt of specific pulses transmitted through the interstitial tissues of the body transmitter device (40) generates trains of modulated pulses applied to electrodes (22, 24), and a receiver (50) processes (e.g., filter, amplify and demodulate) pulses collected on electrodes (22?, 24?). The receiver circuits (50) are selectively activated from a dormant (sleep) state in which they are not powered by a power source (34), to an operational (active) state in which they are powered and able to process (e.g., filter, amplify and demodulate) the collected pulses specific wake-up pulse train, configured in a predetermined characteristic pulse pattern triggers passive wake-up circuits (66) in the receiver (50) to switch the receiver circuits from the sleep state to the operational state.

Abstract: An active medical device such as pacemaker, defibrillator and/or resynchronizer with automatic optimization of atrioventricular delay is disclosed. The active medical device is adapted for analyzing a signal delivered by a hemodynamic sensor such as an endocardial acceleration sensor, whose variation according to the AVD is represented by a sigmoid function. An optimal AVD is searched by: applying a reference AVD (XC), at least one left AVD (XL, XLL) and at least one right AVD (XR, XRR); measuring the corresponding hemodynamic parameters (Y1, Y2, Y3, Y4, Y5); evaluating the second derivative of the function at the respective points (XC, Y3; XL, Y2, XR, Y4) of the characteristic corresponding to the reference AVD, to the left AVD and to the right AVD; estimating from these values of second derivatives, the position of an intermediate point of the characteristic for which the second derivative is zero or minimum, and determining the corresponding AVD for that intermediate point as the optimal AVD.

Abstract: An active implantable medical device for cardiac resynchronization with automatic and almost in real time optimization of the interventricular and atrio-ventricular delays is disclosed. The active implantable medical device includes a closed-loop for continuously controlling the atrio-ventricular delay AVD and the inter-ventricular delay VVD according to a hemodynamic signal delivered by a hemodynamic sensor. The closed-loop provides controlled modulation (38) and demodulation (42) the AVD, and modulation (48) and demodulation (52) the VVD, the modulation and demodulation being functionally interdependent (54, 56) by a sequence of alternating operation. A closed-loop regulator (36) for controlling the AVD receives as input an error signal (EAVD) delivered based on demodulating the AVD (42) and outputs an AVD signal. A closed-loop regulator (46) for controlling the VVD receives as input a signal error (EVVD) based on demodulating the DVV and outputs a VVD signal.

Abstract: Reconstruction of a surface electrocardiogram from far field signals extracted from an endocardial electrogram in an active medical device is disclosed. The device collects a ventricular EGM signal (EGMV) and an atrial EGM signal (EGMA), and extracts a ventricular far field signal component (FFV) and an atrial far field signal component (FFA). The ventricular and atrial far field signal components are combined to deliver as an output a reconstructed surface electrogram ECG signal (ECGj*). The ventricular and atrial far field signals are respectively extracted from the collected ventricular and atrial EGM signals (FFV, FFA). The reconstruction of the ECG is operated by ventricular (18) and atrial (16) far field signal estimator filters. According to one embodiment, the far field signal estimator filters are linear or nonlinear filters, receiving as input the far field signal components. An adder (20) adds the filtered signals and delivers as output the reconstructed ECG signal (ECGj*).

Abstract: An active medical device using non-linear filtering for the reconstruction of a surface electrocardiogram (ECG) from an endocardial electrogram (EGM) is disclosed. The device for the reconstruction of the surface ECG comprises: a plurality of inputs, receiving a corresponding plurality of EGM signals from endocardial or epicardial electrogram (x1[n], x2[n]) each collected on a respective EGM derivation of a plurality of EGM derivations, and at least one output delivering a reconstructed surface ECG electrocardiogram signal (y[n]), related to an ECG derivation, and a non-linear digital filter (12?, 12?, 14) with a transfer function that determines the reconstructed ECG signal based on said plurality of input EGM signals. The non-linear digital filter includes a Volterra filter type (12, 12?, 12?) whose transfer function includes a linear term (h1) and at least one quadratic (h2) and/or cubic (h3) term(s).