Telectronics Pacing Systems, Inc.

Pacesetter, Inc.

Other

Dow Corning Corporation

Bruce M Steinhaus

Tibor A Nappholz

Richard M Lu

Albert K Dawson

Saul E Greenhut

Ken Koestner

James A Nolan

Randy T Wells

Peter A Crosby

Robert A Morris

Edward H Cully

Carey V Campbell

Benjamin M Trapp

Robert L Cleek

Thomas G Triebes

Thane L Kranzler

Chih-ming James Chiang

Theresa A Holland

Mei Li

Michael J Vonesh

Cody L Hartman

Jeffrey B Duncan

Paul D Gassler

Nathan L Friedman

Daniel Cooper

Kent E Samuelson

Alan D Bernstein

John W Camerlo

Fred L Vance

Fred I Vance

Anne Curtis

William N Hursta

Janice Nolan

Stephen M Quist

Gregory Lostracco

Peter Heicksen

Paul D Drumheller

Daniel L Crandall

James F Davidson

An implanted pacemaker senses intrinsic atrial events and generates corresponding pacing pulses. The atrial events are also monitored for a precursor of an atrial fibrillation episode. If such a precursor is detected, the pacemaker generates therapy designed to prevent the atrial fibrillation episode. For example, the atrium and/or the ventricle may be overdriven at a pacing rate above the intrinsic rate.

Apparatus for preventing atrial fibrillation using precursors

A rate responsive implantable pacemaker generates a metabolic demand parameter such as a thoracic impedance which is converted into a corresponding metabolic indicated parameter. During the conversion, intermediate parameters, such as either tidal volume and respiration rate, or a derivative of the metabolic demand parameter are used by a cross-check circuit to insure that artefacts due for example to stroke volume noise are eliminated. The peak limiter is used to limit the metabolic indicated rate to an acceptable range. Both protection circuits use fuzzy logic components.

Rate-responsive pacemaker with noise-rejecting minute volume

A graphic user interface for a cardiac implant, such as an implant programmer, includes image generators for generating multiple images on a screen, each image corresponding to as representation of a parameter related to the operation of the implant or a cardiac function, and an indicia generator for superimposing on the images an indicia indicative of the interrelation between the parameters. The indicia allows a user to obtain a clear understanding and appreciation of the cause and effect rules between various cardiac parameters and/or functions, the parameters or functions could be actual, i.e., obtained from the implant and/or the patient's heart, or they can be simulated to provide the user an indication on how the pacemaker will operate under these simulated conditions parameters.

Pacemaker programmer menu with selectable real or simulated implant data

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.

Minute volume rate-responsive pacemaker using dual unipolar leads

A pacemaker is provided in which ventricular rate instability is detected and automatically corrected by gradually increasing the ventricular pacing rate. Once the ventricle is stabilized, its pacing rate is gradually decreased as much as possible without losing ventricular stability. Ventricular instability can be a result of an atrial tachyrhythmia such as atrial fibrillation. Therefore, if the pacemaker is a dual chamber pacemaker, its operation is switched to a single chamber pacing mode thereby decoupling the ventricular pacing signals from the atrial pacing signals and atrial triggered ventricular pacing is inhibited until the atrial fibrillation terminates.

Apparatus and method for stabilizing the ventricular rate of a heart

A clinical programming system is disclosed for use with an implanted cardiac pacemaker to automatically determine the minimum pacing energy which is necessary to evoke an atrial depolarization. The system utilizes a series of pacing pulses of progressively decreasing energies to stimulate the atrium and detects following R-waves. The absence of an R-wave indicates the loss of atrial capture.

Automatic atrial pacing pulse threshold determination utilizing an

A clinical programming system for use with an implanted cardiac pacemaker to automatically determine the minimum pacing energy which is necessary to evoke an atrial depolarization. The system utilizes a series of pacing pulses of progressively decreasing energies to stimulate the atrium, and detects an evoked response during the AV delay interval that follows each pulse. Initial P-wave intervals are subjected to morphological analysis to generate a P-wave template. Subsequent intervals are similarly analyzed and the results compared with the template. The absence of similarity with the template indicates the loss of atrial capture and that the minimum pacing energy has been reached.

Automatic atrial pacing threshold determination utilizing an external

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.

Leadless implantable sensor assembly and a cardiac emergency warning

A clinical programming system is disclosed for use with an implanted cardiac pacemaker to automatically determine the minimum pacing energy which is necessary to evoke a ventricular depolarization. The system utilizes a series of pacing pulses of progressively decreasing energies to stimulate the ventricle, and detects evoked responses through measurements of the integrals of the R-waves provided by a surface electrocardiogram. Upon loss of capture, the minimum pacing energy is a function of the energy of the last pacing pulse which evoked a ventricular depolarization.

Automatic ventricular pacing pulse threshold determination utilizing an

A time domain reflectometry (TDR) impedance sensor is provided for measuring body impedance along a lead or catheter implanted in a patient's cardiovascular system. The TDR sensor applies an electrical stimulus to the lead and measures reflections echoed from impedance variations along and distal to the lead, which are superimposed on the applied stimulus. The measured signals may be analyzed with respect to time-of-flight and distance along the lead to detect a plurality of physiologically meaningful signals.

Time domain reflectometer impedance sensor method of use and implantable

A patient-implantable cardiac stimulation apparatus adapted to measure body impedance, derive at least one physiological parameter from the impedance measurement, sample a time sequence of the physiological parameter and transmit the sequence to an external monitoring device for display and analysis. The apparatus may also sense intracardiac electrograms while it is measuring body impedance and deriving the physiological parameter, in which case it formats and transmits a combined intracardiac electrogram and physiological signal to the monitoring device.

Apparatus and method for measuring, formatting and transmitting combined

A method and apparatus for detecting cardiac arrhythmias are disclosed. The detecting method and apparatus sense cardiac electrical signals when the heart is functioning in a known cardiac state, such as a physiologically normal cardiac state, then define and store an array of amplitude windows wherein each sample in the array of amplitude windows corresponds to a sample of the known cardiac signal. Each amplitude window delineates a range of signal amplitudes bracketing the amplitude of the known cardiac electrical signal sample. The array of amplitude windows corresponds in time to periodically occurring known cardiac signal samples occurring within a predetermined time of interest. Subsequently, when the heart is functioning in an unknown cardiac state, the method and apparatus monitor cardiac electrical signals by time aligning samples and comparing, on a sample by sample basis, the amplitude of unknown state cardiac signal samples with the amplitude range within the stored array of amplitude window samples. The relative number of samples falling outside the amplitude windows is the basis for analyzing cardiac signal morphology for the purpose of detecting cardiac arrhythmias.

Detection of cardiac arrhythmias using template matching by signature

A method and apparatus for aligning periodic cardiac signal waveforms for the purpose of signal averaging over a number of cardiac cycles. The aligning method and apparatus sense cardiac electrical signals over a number of cardiac cycles, store a template characterizing these signals, reduce the data rate of the same sensed signals by temporal data compression, and store a compressed template sequence. Subsequently, the method and apparatus perform signal averaging by monitoring cardiac electrical signals, storing samples of these signals, temporally compressing these samples and scan correlating the compressed samples with the previously stored compressed template sequence to derive correlation coefficients. Thereafter, the method and apparatus utilize the maximum correlation coefficient to roughly align the monitored waveform with the averaged signal, and then they scan correlate a portion of the noncompressed monitored waveform adjacent to the maximum correlation coefficient with a corresponding portion of the non-compressed template to provide precise alignment of the monitored waveform with the averaged signal.

Signal averaging of cardiac electrical signals using temporal data

A method and apparatus for detecting cardiac arrhythmias in a patient's heart is disclosed. The monitoring method and apparatus sense cardiac electrical signals when the heart is functioning in a known cardiac state, then characterize this known cardiac state by storing a temporally compressed template of time sequence samples. The method and apparatus allow testing during multiple different cardiac states and provide for storage of templates associated with each state. Subsequently, when the heart is functioning in an unknown cardiac state, the method and apparatus monitor cardiac electrical signals by temporally compressing samples and scan correlating these samples with the previously stored template sequences to derive correlation coefficients. The method and apparatus then use these correlation coefficients to characterize cardiac function.

Detection of cardiac arrhythmias using correlation of a cardiac

A method and apparatus for storing a representation of a cardiac signal by compressing the data using scan correlation and temporal data compression techniques. The method and apparatus sense cardiac signals when the heart is functioning in a known cardiac state, then characterize this known state by storing a temporally compressed template of time sequence samples. The method and apparatus may perform testing for multiple different cardiac states and store templates associated with each state. Subsequently when the heart is functioning in an unknown cardiac state, the method and apparatus monitor cardiac signals by temporally compressing samples and scan correlating these samples with the previously stored templates to derive correlation coefficients. These correlation coefficients are a basis for identifying and classifying cardiac signal waveforms. For waveforms which correlate highly with a particular template, analysis of the timing of the maximum correlation coefficient provides a fiducial time which designates the time relationship of waveforms within different cardiac cycles. The method and apparatus store information in the form of templates, fiducial timing markers, and waveform occurrence counts. This data provides the information necessary to subsequently reproduce a long-term signal record.

Growing community of inventors

Parker, CO, United States of America

Bruce M Steinhaus