Respiratory Movement Patents (Class 607/20)
  • Patent number: 6044300
    Abstract: A heart pacemaker which is arranged to stimulate the apical area of the heart. Stimulation of this area provides synchronous mechanical contraction of the left and right ventricles and overcomes the problem of pacemaker induced left bundle branch block type conduction disturbance. The pacemaker has a base surface which conforms to the apical area of the heart and mounts a plurality of epicardial stimulating electrodes. Selection of electrodes can be made to provide the most clinically appropriate stimulation. An opposite side of the pacemaker is arranged to contact the diaphragm and is proved with sensing electrodes to sense activity of the diaphragm and adjust pacing of the heart in accordance with changes in physical activity of the patient. The electrodes used are preferably of capacitive construction, having first and second capacitive plates either side of a dielectric formed by he body of the pacemaker.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: March 28, 2000
    Inventor: Noel Desmond Gray
  • Patent number: 6038475
    Abstract: An accelerometer and sensor assemblies for medical implantable devices such as pacemakers, cardioverters, IPGs, PCDs, defibrillators, ICDs, and the like, includes at least one intermediate metallization layer sandwiched between a first lower surface of at least one upper sheet formed from a piezoelectric material surface, and a second upper surface of at least one lower sheet formed from a piezoelectric material. The at least one upper sheet has a first outer edge disposed between its first upper and first lower surfaces. The at least one lower sheet has a second outer edge disposed between its second upper and second lower surfaces. The at least one intermediate metallization layer is not disposed at all locations between the first lower surface and the second upper surface, but extends to an external region disposed between the first outer edge and the second outer edge, and is electrically connected to the external region.
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: March 14, 2000
    Assignee: Medtronic, Inc.
    Inventors: James M. Sikorski, David A. Ruben
  • Patent number: 5964788
    Abstract: In an implantable pacemaker the pacing rate is adjusted in synchrony with the respiration of the patient to thereby mimic respiratory sinus arrhythmia noted in healthy patients. Preferably, first a metabolic demand parameter pacing parameter is derived from a metabolic demand of the patient, such as minute volume, and then this parameter is adjusted using a respiration detector. The adjustment may be made dependent on the exercise level of the patient, his age and his physical fitness.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: October 12, 1999
    Assignee: Pacesetter, Inc.
    Inventor: Saul E. Greenhut
  • Patent number: 5931858
    Abstract: An implantable electronic circuit for monitoring a patient's aerobic capacity includes an accelerometer for detecting the onset and termination of a period of exercise and a means for measuring the patient's minute volume. By computing the time interval from the cessation of exercise to the point where the patient's minute volume reaches a predetermined value at or near an at-rest value thereof, a measure of aerobic capacity relating to a patient's physical fitness can be determined.
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: August 3, 1999
    Assignee: Cardiac Pacemakers, Inc.
    Inventors: Veerichetty A. Kadhiresan, Arthur L. Olive, Bruce R. Jones
  • Patent number: 5817136
    Abstract: A rate responsive pacemaker includes a noise sensor for sensing noise on the leads. If noise is detected, the pacemaker switches to a mode wherein a metabolic demand parameter is ignored. The noise is preferably detected by using test signals which are also used to measure the metabolic demand parameter.
    Type: Grant
    Filed: May 2, 1997
    Date of Patent: October 6, 1998
    Assignee: Pacesetter, Inc.
    Inventors: Tibor A. Nappholz, Saul E. Greenhut, Chih-ming James Chiang
  • Patent number: 5800470
    Abstract: A physiologic rate responsive pacer which alters the pacer's escape interval in response to the patient's respiratory minute ventilation derived from the electromyogram of selected respiratory muscle groups. The directly detected electromyogram (EMG) signal is amplified and band passed filtered, processed to remove any electrocardiogram (ECG) or pacing impulse signal, full-wave rectified, processed to develop a moving time average signal from which the peak, the maximal slope, and the average slope of the EMG moving time average may be calculated and processed in conjunction with the inspiratory and expiratory times between successive slope detections of the moving time average EMG to develop a rate control signal representative of minute ventilation.
    Type: Grant
    Filed: March 11, 1996
    Date of Patent: September 1, 1998
    Assignee: Medtronic, Inc.
    Inventors: Paul M. Stein, Tom D. Bennett, Terrell M. Williams
  • Patent number: 5792208
    Abstract: A heart pacemaker which is arranged to stimulate the apical area of the heart. Stimulation of this area provides synchronous mechanical contraction of the left and right ventricles and overcomes the problem of pacemaker induced left bundle branch block type conduction disturbance. The pacemaker has a base surface which conforms to the apical area of the heart and mounts a plurality of epicardial stimulating electrodes. Selection of electrodes can be made to provide the most clinically appropriate stimulation. An opposite side of the pacemaker is arranged to contact the diaphragm and is proved with sensing electrodes to sense activity of the diaphragm and adjust pacing of the heart in accordance with changes in physical activity of the patient. The electrodes used are preferably of capacitive construction, having first and second capacitive plates either side of a dielectric formed by he body of the pacemaker.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: August 11, 1998
    Inventor: Noel Domond Gray
  • Patent number: 5792196
    Abstract: A rate responsive pacemaker senses an instantaneous metabolic indicative parameter such as minute volume and monitors this parameter over an extended time period of 30 days. A corresponding cumulative rate control parameter is generated. The cumulative rate parameter is converted into a metabolic pulsing rate for generating pulses in accordance with a set of physical activity parameters.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: August 11, 1998
    Inventors: Daniel Cooper, Dean J. MacCarter
  • Patent number: 5792200
    Abstract: A programmable pacemaker and program therefor are disclosed, wherein the pacer is programmed to operate in a first pacing mode whenever the measured atrial rate is less than a certain threshold switching rate R.sub.T, and to operate in a second pacing mode whenever the measured atrial rate is greater than the threshold switching rate R.sub.T. The threshold switching rate R.sub.T is varied based on either a programmed algorithm or the measured value of one or more sensed parameters. In another embodiment, a hysteresis is introduced, so that the rate at which the pacer switches back to its low-activity mode is lower than the rate that triggers a switch to the high-activity mode.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: August 11, 1998
    Assignee: Sulzer Intermedics Inc.
    Inventor: Maurice A. Brewer
  • Patent number: 5674259
    Abstract: A heart pacemaker which is arranged to stimulate the apical area of the heart. Stimulation of this area provides synchronous mechanical contraction of the left and right ventricles and overcomes the problem of pacemaker induced left bundle branch block type conduction disturbance. The pacemaker has a base surface which conforms to the apical area of the heart and mounts a plurality of epicardial stimulating electrodes. Selection of electrodes can be made to provide the most clinically appropriate stimulation. An opposite side of the pacemaker is arranged to contact the diaphragm and is provided with sensing electrodes to sense activity of the diaphragm and adjust pacing of the heart in accordance with changes in physical activity of the patient. The electrodes used are preferably of capacitive construction, having first and second capacitive plates either side of a dielectric formed by the body of the pacemaker.
    Type: Grant
    Filed: June 15, 1995
    Date of Patent: October 7, 1997
    Inventor: Noel Desmond Gray
  • Patent number: 5562712
    Abstract: A rate-responsive pacemaker including a pulse generator for providing pacing current pulses at a controlled rate and two unipolar leads are provided. The pulse generator also applies a measuring current between one of the electrodes and a reference point in the pacemaker. The impedance between the other electrode and the reference point is measured across a lung of the patient. The impedance of the patient varies as a function of patient's pleural pressure, and therefore, the impedance thus represents the patient's minute volume. The rate of pacing is automatically adjusted in response to changes in the patient's minute volume.
    Type: Grant
    Filed: November 25, 1994
    Date of Patent: October 8, 1996
    Assignee: Dow Corning Corporation
    Inventors: Bruce Steinhaus, Albert Dawson, Richard Lu
  • Patent number: 5524632
    Abstract: A physiologic rate responsive pacer which alters the pacer's escape interval in response to the patient's respiratory minute ventilation derived from the electromyogram of selected respiratory muscle groups. The directly detected electromyogram (EMG) signal is amplified and band passed filtered, processed to remove any electrocardiogram (ECG) or pacing impulse signal, full-wave rectified, processed to develop a moving time average signal from which the peak, the maximal slope, and the average slope of the EMG moving time average may be calculated and processed in conjunction with the inspiratory and expiratory times between successive slope detections of the moving time average EMG to develop a rate control signal representative of minute ventilation.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: June 11, 1996
    Assignee: Medtronic, Inc.
    Inventors: Paul M. Stein, Tom D. Bennett, Terrell M. Williams
  • Patent number: 5522860
    Abstract: Process of control of an implantable active medical device. The device is under the responsive control of (enslavement to) a sensed physiological parameter. A representative magnitude of the physiological parameter is measured in the presence of a useful signal to determine a value of the parameter. Then, in the absence of the useful signal, another measure is made to determine the noise. The noise is compared to a threshold corresponding to an unacceptable level of noise. In case of crossing the noise threshold, this crossing is taken in account by a control device with a view to possible suspension of a function of the device if there is too much noise.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: June 4, 1996
    Assignee: ELA Medical S.A.
    Inventors: Renzo D. Molin, Catherine Paris
  • Patent number: 5501702
    Abstract: A cardiac pacemaker having switching circuitry for dynamically re-assigning the electrical function of a plurality of electrodes coupled thereto. The pacemaker is provided with switching circuitry for allowing the sensing signals from a plurality of implanted electrodes may be selectively applied to sensing and detection circuitry in the pacemaker. Controller circuitry in the pacemaker controls the operation of the switching circuits and of a rheography current pulse generator such that a plurality of time slots are defined during a sensing interval. During successive time slots, a different electrical function may be assigned to the same electrode. Also disclosed is a method of operating such a pacing system.
    Type: Grant
    Filed: July 19, 1994
    Date of Patent: March 26, 1996
    Assignee: Medtronic, Inc.
    Inventors: Gianni Plicchi, Massimo Ceccarelli
  • Patent number: 5404877
    Abstract: A leadless implantable cardiac arrhythmia alarm is disclosed which continuously assesses a patient's heart function to discriminate between normal and abnormal heart functioning and, upon detecting an abnormal condition, generates a patient-warning signal. The alarm is capable of sensing impedance measurements of heart, respiratory and patient motion and, from these measurements, generating an alarm signal when the measurements indicate the occurrence of a cardiac arrhythmia. Because it requires no external leads or feedthrough connectors, the hermetically-sealed patient alarm is minimally invasive and results in reduced trauma to a patient.
    Type: Grant
    Filed: June 4, 1993
    Date of Patent: April 11, 1995
    Assignee: Telectronics Pacing Systems, Inc.
    Inventors: James A. Nolan, Bruce M. Steinhaus, Tibor A. Nappholz
  • Patent number: 5355894
    Abstract: For generating a signal corresponding to the respiration volume per unit of time of a patient, a signal component correlated with the respiration is filtered out of a measured impedance signal acquired in the region of the heart of the patient, and the zero-axis crossings of this signal component are detected and the maximum values respectively arising in between two successive pairs of zero-axis crossings are identified in terms of amplitude. These maxima are added during a prescribed time interval to form a value corresponding to the respiration volume per unit of time.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: October 18, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventor: Ake Sivard
  • Patent number: 5318597
    Abstract: A rate adaptive cardiac rhythm management device in which the pacing rate is adjusted in accordance with changes in the patient's minute ventilation. An adaptive four-pole elliptic digital filter, preferably implemented in software, functions to attenuate any signal components due to cardiac activity and motion from the minute ventilation signal over the range of breathing frequencies encountered in going from a sedentary state to active exercise. The pacemaker incorporates a microprocessor-based controller that is programmed to compute from peak-to-peak excursions of the sensed parameter the instantaneous tidal volume. Likewise, it computes, using a zero-crossing technique, the breathing interval. Knowing the breathing interval and the instantaneous tidal volume, it is possible to compute minute ventilation over a predetermined time interval and it is that factor that is employed in developing the ultimate control signal used to vary the stimulating rate between a lower rate limit and an upper rate limit.
    Type: Grant
    Filed: March 15, 1993
    Date of Patent: June 7, 1994
    Assignee: Cardiac Pacemakers, Inc.
    Inventors: John A. Hauck, Arthur L. Olive
  • Patent number: 5303702
    Abstract: A cardiac pacemaker having a pacing rate responsive to a control function of a physiological parameter indicative of activity levels. The coefficients of the function are automatically calculated and modified in response to the trend of the measured physiological parameter in order to correspond to the patient real needs. For monitoring the physiological parameter minute ventilation (VE), the basic value VE low and maximum value VE max are calculated in order to vary the slope and intercept of the straight line representative of the control relation of the pacing rate FC by the minute volume VE.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: April 19, 1994
    Assignee: ELA Medical
    Inventors: Jean-Luc Bonnet, Odile Malherbe
  • Patent number: 5249572
    Abstract: Controlling a cardiac pacemaker wherein the cardiac pacing rate is controlled according to a measure of the metabolic demand. The average minute ventilation MV-8-0 is measured over the eight last breathing cycles (first one to eighth one), and it is compared with the average minute ventilation MV-8-1 over the previous eight breathing cycles (ninth one to sixteenth one), and it is determined that an effort phase is present when MV-8-0>MV-8-1, and that a recovery phase is present when MV-8-0<MV-8-1. These determinations are used to determine whether sensed changes in the ventilation correspond to transitions between the effort and recovery or ventilation gaps or artifacts so that the cardiac pacing rate is not decreased during an effort.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: October 5, 1993
    Assignee: ELA Medical
    Inventor: Jean-Luc Bonnet
  • Patent number: 5243979
    Abstract: A cardiac pacemaker of the type including a sensor responsive to the patient's metabolic demand for oxygenated blood and which varies the pacing rate in response to the output of the sensor. In the disclosed embodiment, a piezoelectric sensor bonded to the inside surface of the pacemaker's outer shield delivers a pulsatile sensor signal to activity circuitry, where the different peak values of the pulsatile signal correspond to different levels of patient activity. The activity circuit defines a plurality of sensor signal threshold levels. Rate control circuitry increases the pacing rate of the pacemaker by amounts corresponding to the threshold level exceeded by recent peak values of said pulsatile signal; peaks of said pulsatile signal which exceed only the lowest of the thresholds cause the smallest increase in the pacing rate, while sensor signals which exceed higher thresholds cause larger increases in the pacing rate.
    Type: Grant
    Filed: November 15, 1991
    Date of Patent: September 14, 1993
    Assignee: Medtronic, Inc.
    Inventors: Paul M. Stein, David L. Thompson