Pacesetter, Inc.

Chih-ming James Chiang

Tibor A Nappholz

Saul E Greenhut

Daniel Cooper

Bruce M Steinhaus

Alan D Bernstein

A rate responsive implantable pacemaker generates a metabolic demand parameter which is converted into a corresponding metabolic indicated parameter. The parameter is used to determine certain characteristics related to an exercise period and the patient, including exercise duration and intensity. These characteristics are used to dynamically calculate an exercise recovery period during which the pacing rate is elevated above a rate indicated by the metabolic parameter. Preferably, fuzzy logic circuitry is used for this purpose.

Rate responsive pacemaker with exercise recovery using minute volume

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.

Rate-responsive pacemaker with minute volume determination and EMI

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 diagnostic device makes use of knowledge based rule system for making a prognosis of a cardiac malfunction based on operation parameters and/or patient characteristics received from a cardiac implant. The device generates a symptoms vector from the information received from the implant, and using the expert rules to generate an appropriate prognosis. Both pathological problems and programming problems may be detected in this manner.

Fuzzy logic expert system for an implantable cardiac device

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.

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Chandler, AZ, United States of America

Chih-ming James Chiang