Medtronic, Inc.

Peter W Wohlgemuth

Mattias Rouw

Henk Westendorp

Harry W M De Bruyn

Geeske Van Oort

Peter M Van Dam

Dave J Munneke

Gustaaf Stoop

Jacob Dave Munneke

Anton L Huijnen

J Dave Munneke

There is provided an implantable cardiac pacing system or other cardiac monitoring system having an enhanced capability to classify intracardiac signals through a combination of DSP techniques and software algorithms. The implantable device has one or more DSP channels corresponding to different signals which are being monitored. Each DSP channel most preferably amplifies the incoming signal, converts the signal from analog to digital form, digitally filters the converted signals to provide a filtered signal, operates on the filtered signal to provide a slope signal, determines from the filtered and slope signals when an intracardiac event has been detected, signal processes the filtered and slope signals for a predetermined analysis interval after threshold crossing, and generates a plurality of wave parameters corresponding to the signal. The generated wave parameters are further operated on by a programmable algorithm to classify the detected event based upon DSP-generated parameters, and then monitor or detect the onset, development or presence of an undesired heart condition in a patient. The system may further provide for the delivery of treatment, storage of intracardiac data, or provision of a warning to a patient or physician in response to the detection of such a heart condition.

Cardiac pacing system with improved physiological event classification and heart monitoring based on DSP

A cardiac pacing system and method incorporate DSP processing and software algorithms for collecting signal amplitude data and noise data, and organizing the data for automatic checking of signal channel gain and signal detection sensitivity. Unfiltered signals are used to obtain values representative of maximum amplitude, which values are stored in a gain histogram, from which determination of the percentage of clipped signals can be made. Gain is adjusted by limiting clipping to a predetermined range of allowed clipping, to optimize use of the DSP range. The signals, both P waves and R waves for a dual chamber system, are also processed by DSP and parameters representing maximum amplitudes are stored in amplitude histograms. At the same time, noise is analyzed for respective windows of time following each ventricular event, and noise amplitude data is stored in noise histograms. After a predetermined waiting period, the signal amplitude and noise histograms are analyzed and compared, and for each channel the sensitivity is adjusted to fall between a calculated noise floor and the lowest bin of the amplitude histogram that contains valid data.

Implantable medical device with autosensitivity algorithm for controlling sensing of cardiac signals

A method and system for ventricular fusion prevention is provided. It is determined whether an atrial sense occurred within a prior wait time and a scheduled ventricular pace is administered if no atrial sense occurred. If an atrial sense occurred and a ventricular sense follows within an additional wait time, the scheduled ventricular pace is canceled to avoid a fusion beat. If an atrial sense occurred and no ventricular sense follows within an additional wait time, the scheduled ventricular pace is administered. In another embodiment, the max AV interval is increased if too many scheduled ventricular paces are canceled to avoid fusion beats.

Method and system for ventricular fusion prevention

A system for a method of classifying distinct signals sensed from an electrode of an implantable cardiac pacing system positioned within an atrium of a heart of a patient is disclosed. The cardiac pacing system includes a pulse generator for generating pacing pulses and a controller for controlling the operation of a pacemaker. The method includes collecting atrial event signals consisting of P-wave signals and far field R-wave signals. An interim form factor histogram is generated based upon a form of collected atrial event signals. The interim form factor histogram includes an interim P-wave form factor histogram and an interim far field R-wave form factor histogram, each having bins of atrial event signals. A previously generated form factor histogram is weighted and combined with the interim form factor histogram to create a representative form factor histogram. The representative form factor histogram is analyzed to determine if a minimal safety margin is located between the representative P-wave form factor histogram and the representative far field R-wave form factor histogram. Atrial event signals are classified by form as either P-wave signals or far field R-wave signals based upon the representative form factor histogram.

System and method for classifying sensed atrial events in a cardiac pacing system

A method for determining a representative noise floor in a cardiac pacing system from which future events are measured is provided. An event amplitude is determined. Pluralities of noise levels are recorded, when each of the plurality of noise levels is less than a predetermined percentage of the event amplitude. The noise floor is determined as an absolute maximum value of the plurality of recorded noise levels.

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Neukirchen, Germany

Peter W Wohlgemuth