Abstract: RF telemetry for an active medical device such as active implant or programmer for such implant. The device includes at least one RF antenna (14), and at least one RF telemetry transmitter/receiver (44) with, for coupling to the antenna, an associated band rejection filter (54). The band rejection filter (54) comprises at least one volume acoustic wave BAW resonator (40) of the SMR type with insulation by Bragg acoustic reflector (42). The device can be a multi-band device comprising a plurality of RF transmitters/receivers (12, 44) operating in respective distinct bands of frequencies such as the 402˜405-MHz, 863˜870-MHz, 902˜928-MHz and 2.4-GHz bands or by UWB transmission.

Abstract: An active implantable medical device including bidirectional communications between a generator and sensors or actuators located at the distal extremity of a lead. A lead (14) is connected at its proximal end to a generator (10) and has at the distal end electrodes (38, 42) able to come in contact with surrounding tissues. A two-wire connection (34, 36) connects these electrodes to the generator. The lead incorporates transducers (24, 26) of sensor or actuator type. The generator includes circuits for sending and receiving digital data (46,48,50,54,56) capable of producing instructions to one of the transducers and to receive and decode information from one of the transducers in response to a specific instruction produced by the generator. The transducer is able to receive, decode and carry out the aforementioned controls, as well as send data in response.

Abstract: A circuit for controlled commutation of multiplexed electrodes, for an active implantable medical device. This circuit is located in a lead equipped with multiplexed sensing/pacing electrodes. This circuit decodes a signal generated by a generator, commanding a series of switches, which ensures selective coupling of the various electrodes to the proximal and distal terminals of the generator. This signal is a modulated signal comprising a coded series of logic pulses defining a particular configuration for coupling the lead electrodes to the proximal or distal terminal of the generator. The signal comprises a micropulse, that precedes the coded series of logic pulses and has an amplitude and duration lower than the amplitude and duration of each of the logic pulses. The detection of this micropulse activates, in response, all the circuit switches to an open position over a duration (PHASE 1) at least equal to the duration of reception of the coded series of logic pulses.

Abstract: The reconstruction of a surface electrocardiogram based upon an endocardial electrogram. This method includes: (a) acquisition (10) of a plurality of endocardial electrogram signals (EGM) through a plurality of endocardial derivations defined based upon endocardial electrodes; (b) calculation (12), by combining the endocardial electrogram (EGM) signals acquired at step (a), of the corresponding endocardial vectogram (VGM); (c) angular resealing (14) of the orthonormated mark of the endocardial vectogram (VGM) with that of the surface vectocardiogram (VCG); (d) estimation (16), based upon the endocardial vectogram (VGM) calculated at step (b), of a reconstructed surface vectocardiogram (VCGreconstructed); and (e) calculation (18) of the surface electrocardiogram (ECG) corresponding to said reconstructed surface vectocardiogram (VCGreconstructed).

Abstract: The reconstruction of a surface electrocardiogram based upon an endocardial electrogram. This method includes: (a) acquisition (10) of a plurality of endocardial electrogram signals (EGM) through a plurality of endocardial derivations defined based upon endocardial electrodes; (b) calculation (12), by combining the endocardial electrogram (EGM) signals acquired at step (a), of the corresponding endocardial vectogram (VGM); (c) angular resealing (14) of the orthonormated mark of the endocardial vectogram (VGM) with that of the surface vectocardiogram (VCG); (d) estimation (16), based upon the endocardial vectogram (VGM) calculated at step (b), of a reconstructed surface vectocardiogram (VCGreconstructed), and (e) calculation (18) of the surface electrocardiogram (ECG) corresponding to said reconstructed surface vectocardiogram (VCGreconstructed).

Abstract: RF telemetry for an active medical device such as active implant or programmer for such implant. The device includes at least one RF antenna (14), and at least one RF telemetry transmitter/receiver (44) with, for coupling to the antenna, an associated band rejection filter (54). The band rejection filter (54) comprises at least one volume acoustic wave BAW resonator (40) of the SMR type with insulation by Bragg acoustic reflector (42). The device can be a multi-band device comprising a plurality of RF transmitters/receivers (12, 44) operating in respective distinct bands of frequencies such as the 402˜405-MHz, 863˜870-MHz, 902˜928-MHz and 2.4-GHz bands or by UWB transmission.

Abstract: Apparatus for telemetry equipment for communication with an active device implanted in the thoracic area of a patient This equipment includes a wave collector (16) essentially sensitive to a magnetic field so as to allow an exchange of signals through magnetic coupling (i.e., an inductive channel) with the implanted device (14). The wave collector is connected to an electronic circuit package (24) for transmission/reception and signal processing of acquired data and programming. The apparatus further comprises a cloth (10) in the form of a vest to be worn by and able to cover at least one part of the patient's anatomy, a support structure (18) for receiving and supporting the wave collector, and adjustable members able to fix the support structure at a chosen location of the cloth, for example, by means of hooking tapes (20) disposed on the support (18) and cooperating surface material on the cloth.

Abstract: An active implantable medical device with RF telemetry comprising subcutaneous ECG electrodes. The case (12) of the device comprises electrodes (20, 22, 24, 26) for collecting subcutaneous ECG signals coming into contact with the patient's tissues surrounding the case after implantation, as well as an RF telemetry antenna (30). These ECG electrodes are surface electrodes and the RF antenna is a surface antenna. The case (12) presents a significantly planar face (16) for mounting the ECG electrodes in an arrangement where these electrodes are significantly coplanar and spaced apart with each other, and receiving the surface RF antenna. A platelet (18) mounted onto the case comprises an insulating substrate comprising on its free face, conductive deposits (20, 22, 24, 26, 30) forming the ECG electrodes and the RF antenna.

Abstract: A circuit for delivering a back-up stimulation voltage in a cycle to cycle capture test for an active implantable medical device such as a pacemaker, defibrillator and/or cardiovertor or a multisite device having an enhanced circuit for delivering back-up stimulation pulses.

Abstract: An active implantable medical device, in particular a pacemaker, cardioverter, defibrillator and/or a multisite device having circuits for measuring a trans-septal bio-impedance. This device is used with electrodes placed in a plurality of distinct respective sites comprising at least one left ventricular site and one right atrial site. These electrodes are connected to a collection circuit for collecting cardiac signals, in particular to detect a potential of depolarization, and to a stimulation circuit, to apply stimulation pulses to at least some of the aforementioned sites. The device evaluates the cardiac flow by obtaining an intracardiac measurement of the bio-impedance, more particularly measuring the trans-septum impedance bio-between the left ventricle and the right atrium, by injection of a current (16) between an atrial site (RA−) and a ventricular site (LV−), and collection of a differential potential (20) between an atrial site (RA+) and a ventricular site (LV−).

Abstract: Measuring a trans-valvular bio-impedance in an active implantable medical device, in particular, a pacemaker, a defibrillator and/or a cardioverter and/or a multisite device in which electrodes are placed in at least one ventricular site and one atrial site and are connected to at least one circuit for the collection (detection) of cardiac signals, to detect a depolarization potential. The electrodes also are connected to a stimulation circuit to deliver stimulation pulses to at least some of the sites. The trans-valvular bio-impedance is measured by injecting a current between an atrial site and a ventricular site, and collecting a potential differential between an atrial site and a ventricular site. The measurement configuration is a tripolar configuration, with one site common to the injection and the collection, one site dedicated for the injection and one site dedicated for the collection.

Abstract: A process for sampling a cardiac parameter, in particular an intracardiac impedance, in an active implantable medical device such as a pacemaker, defibrillator, cardioverter and/or multisite device. The process includes carrying out in a repeated manner over a plurality of successive cardiac cycles (CYCLE 1 . . . CYCLE 8), the steps of detecting a moment (E) at which a ventricular event occurred, and then sampling the aforesaid signal during each cardiac cycle with a constant sampling step and a predetermined temporal shift (&Dgr;t1 . . . &Dgr;t8) between the detected ventricular event and the first sample in each cycle, this temporal shift being a progressive variable shift from one cycle to the following cycle.

Abstract: An active implantable medical device, in particular a pacemaker, defibrillator and/or cardiovertor of the multisite type providing resynchronization of the ventricles electrodes are placed in at least two sites, right and left, and are connected to a circuit for the collection of cardiac signals, to detect a depolarization potential. Electrodes also are connected to a stimulation circuit, to apply stimulation pulses to at least some of the sites. The device provides resynchronization of the ventricular contraction, by establishing a delay between the times of application of the respective stimulation pulses on the right ventricle (RV) and left ventricle (LV), determining a parameter (z) representative of the degree of synchronization between ventricles, and varying the delay in the direction of the improvement of the aforesaid representative parameter. The parameter is a bio-impedance measurement.

Abstract: An active implantable medical device, in particular a pacemaker, defibrillator or cardioveter of the multisite type, including a circuit for measuring intercardiac impedance. Electrodes are placed in at least one ventricular site and one atrial site, and are connected to a circuit for the collection of cardiac signals, to detect a depolarization potential, as well as to a stimulation circuit, to apply stimulation pluses to at least some of the aforementioned sites. The measurement of a trans-pulmonary bio-impedance is obtained by injecting a current from an injection circuit (16) between the case (18) of the device and a first atrial (RA−) (or ventricular) site, and measuring a differential potential (20) between the case (18) and a point of measurement located in a second atrial (RA+) (or ventricular) site using a collection circuit.

Abstract: A circuit for delivering a back-up stimulation voltage in a cycle to cycle capture test for an active implantable medical device such as a pacemaker, defibrillator and/or cardiovertor or a multisite device having an enhanced circuit for delivering back-up stimulation pulses.

Abstract: A process for the measurement of the complex impedance of a lead for an active implantable medical device, in particular a pacemaker, defibrillator and or cardiovertor. This process includes the steps of producing a stimulation pulse by the discharge on the lead (10) of a tank-capacitor (22) of the device (20), charged beforehand to a given voltage level; measuring the voltage variation (V(t)) at the terminals of the tank-capacitor during the discharge; and determining the lead impedance (Zs) from the voltage thus measured. The measurement stage includes sampling at least three successive values of the voltage at the terminals of the tank capacitor, and the determining stage includes the separate determination of the resistive (Rs) and/or capacitive (CH) components of the complex impedance of the lead from the aforesaid at least three sampled values of voltage thus obtained.

Abstract: A process for sampling a cardiac parameter, in particular an intracardiac impedance, in an active implantable medical device such as a pacemaker, defibrillator, cardioverter and/or multisite device. The process includes carrying out in a repeated manner over a plurality of successive cardiac cycles (CYCLE 1 . . . CYCLE 8), the steps of detecting a moment (E) at which a ventricular event occurred, and then sampling the aforesaid signal during each cardiac cycle with a constant sampling step and a predetermined temporal shift (&Dgr;t1. . . &Dgr;t8) between the detected ventricular event and the first sample in each cycle, this temporal shift being a progressive variable shift from one cycle to the following cycle.

Abstract: An active implantable medical device, in particular a pacemaker, cardioverter, defibrillator and/or a multisite device having circuits for measuring a trans-septal bio-impedance. This device is used with electrodes placed in a plurality of distinct respective sites comprising at least one left ventricular site and one right atrial site. These electrodes are connected to a collection circuit for collecting cardiac signals, in particular to detect a potential of depolarization, and to a stimulation circuit, to apply stimulation pulses to at least some of the aforementioned sites. The device evaluates the cardiac flow by obtaining an intracardiac measurement of the bio-impedance, more particularly measuring the trans-septum impedance bio-between the left ventricle and the right atrium, by injection of a current (16) between an atrial site (RA−) and a ventricular site (LV−), and collection of a differential potential (20) between an atrial site (RA+) and a ventricular site (LV−).

Abstract: An active implantable medical device, in particular a pacemaker, defibrillator or cardioveter of the multisite type, including a circuit for measuring intercardiac impedance. Electrodes are placed in at least one ventricular site and one atrial site, and are connected to a circuit for the collection of cardiac signals, to detect a depolarization potential, as well as to a stimulation circuit, to apply stimulation pluses to at least some of the aforementioned sites. The measurement of a trans-pulmonary bio-impedance is obtained by injecting a current from an injection circuit (16) between the case (18) of the device and a first atrial (RA−) (or ventricular) site, and measuring a differential potential (20) between the case (18) and a point of measurement located in a second atrial (RA+) (or ventricular) site using a collection circuit.

Abstract: Measuring a trans-valvular bio-impedance in an active implantable medical device, in particular, a pacemaker, a defibrillator and/or a cardioverter and/or a multisite device in which electrodes are placed in at least one ventricular site and one atrial site and are connected to at least one circuit for the collection (detection) of cardiac signals, to detect a depolarization potential. The electrodes also are connected to a stimulation circuit to deliver stimulation pulses to at least some of the sites. The trans-valvular bio-impedance is measured by injecting a current between an atrial site and a ventricular site, and collecting a potential differential between an atrial site and a ventricular site. The measurement configuration is a tripolar configuration, with one site common to the injection and the collection, one site dedicated for the injection and one site dedicated for the collection.