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US5161529A Expired / Lapsed US ⏱️ 0.0 years remaining

Cardiac pacemaker with capture verification

Assignee: Intermedics Inc
•
Filing: 1988-12-02
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Granted: 1992-11-10
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Expires: 2008-12-02
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Abstract

Abstract A pacemaker having an electrical stimulation source of known type is provided with a sense amplifier having a switched capacitor circuit which allows switching of the amplifier's bandpass frequency characteristic thereby selectively varying the cardiac signal frequencies subject to sensing. The heart's electrical activity is detected in a first predetermined low frequency range after to delivery of a stimuli to detect evoked electrical activity and a second predetermined high frequency range to detect intrinsic electrical activity. The magnitude of stimuli is varied response to the detected presence or absence of evoked electrical activity.

Inventors

  • 👤 Lawrence J. Stotts
  • 👤 James P. Nelson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 07:07
CPC Classifications
A; A61; A61N; A61N1/00; A61N1/18; A61N1/32; A61N1/36; A61N1/362; A61N1/37; A61N1/371

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 102 words
An implantable cardiac pacemaker comprising: means for generating electrical stimuli to be selectively delivered to a patient's heart; and means for sensing electrical activity of said heart, said sensing means including at least one amplifier, and means for selectively changing the bandpass frequency characteristics of said amplifier during a cardiac cycle to a first predetermined low frequency range for a first period of time after delivery of a stimulus to said heart to detect evoked electrical activity in the heart and to a second predetermined high frequency range for a second period of time to detect intrinsic electrical activity in the heart.
Claim 2
Dependent Claim 102 words
An implantable cardiac pacemaker comprising: means for generating electrical stimuli to be selectively delivered to a patient's heart; and means for sensing electrical activity of said heart, said sensing means including at least one amplifier, and means for selectively changing the bandpass frequency characteristics of said amplifier during a cardiac cycle to a first predetermined low frequency range for a first period of time after delivery of a stimulus to said heart to detect evoked electrical activity in the heart and to a second predetermined high frequency range for a second period of time to detect intrinsic electrical activity in the heart.
Claim 3
Dependent Claim 30 words
The implantable cardiac pacemaker according to claim 1 further comprising means responsive to the presence or absence of evoked electrical activity for adjusting the output of said stimuli generating means.
Claim 4
Dependent Claim 39 words
The implantable cardiac pacemaker according to claim 2 wherein the means for selectively changing frequency characteristics comprises at least one capacitor and means for switching said capacitor into and out of connection with said amplifier at a selected frequency.
Claim 5
Dependent Claim 25 words
The implantable cardiac pacemaker according to claim 3 wherein said means for selectively changing the frequency characteristics further includes a microprocessor controlling said switching means.
Claim 6
Dependent Claim 42 words
The implantable cardiac pacemaker according to claim 1 further comprising means for selectively changing the gain of said amplifier to a first high gain during said first period of time and to a second low gain during said second period of time.
Claim 7
Dependent Claim 30 words
The implantable cardiac pacemaker according to claim 5 further comprising means responsive to the presence or absence of evoked electrical activity for adjusting the output of said stimuli generating means.
Claim 8
Dependent Claim 39 words
The implantable cardiac pacemaker according to claim 6 wherein the means for selectively changing frequency characteristics comprises at least one capacitor and means for switching said capacitor into and out of connection with said amplifier at a selected frequency.
Claim 9
Dependent Claim 25 words
The implantable cardiac pacemaker according to claim 7 wherein said means for selectively changing the frequency characteristics further includes a microprocessor controlling said switching means.
Claim 10
Dependent Claim 28 words
The implantable cardiac pacemaker according to claim 8 wherein said gain changing means comprise a plurality of capacitors and means for selectively connecting said capacitors to said amplifier.
Claim 11
Dependent Claim 17 words
The implantable cardiac pacemaker according to claim 9 wherein said selectively connecting means further comprises a microprocessor.
Claim 12
Dependent Claim 56 words
The implantable cardiac pacemaker according to claim 5 wherein the frequency changing means further comprises means for changing the bandpass frequency characteristics of said amplifier to a third predetermined higher frequency range for a third period of time at least immediately after delivery of said stimulus to the heart and before said first period of time.
Claim 13
Dependent Claim 30 words
The implantable cardiac pacemaker according to claim 11 further comprising means responsive to the presence or absence of evoked electrical activity for adjusting the output of said stimuli generating means.
Claim 14
Dependent Claim 39 words
The implantable cardiac pacemaker according to claim 12 wherein the means for selectively changing frequency characteristics comprises at least one capacitor and means for switching said capacitor into and out of connection with said amplifier at a selected frequency.
Claim 15
Dependent Claim 25 words
The implantable cardiac pacemaker according to claim 13 wherein said means for selectively changing the frequency characteristics further includes a microprocessor controlling said switching means.
Claim 16
Dependent Claim 28 words
The implantable cardiac pacemaker according to claim 14 wherein said gain changing means comprise a plurality of capacitors and means for selectively connecting said capacitors to said amplifier.
Claim 17
Dependent Claim 17 words
The implantable cardiac pacemaker according to claim 15 wherein said selectively connecting means further comprise a microprocessor.
Claim 18
Independent Claim 96 words
A method for adjusting an implantable cardiac pacemaker comprising: generating electrical stimuli to be selectively delivered to a patient's heart, sensing electrical activity of said heart, amplifying sensed electrical activity, changing bandpass frequency characteristics during a cardiac cycle to a first predetermined low frequency range for a first period of time after delivery of a stimulus to said heart, detecting evoked electrical activity in the heart, and changing bandpass frequency characteristics during said cardiac cycle to a second predetermined high frequency range for a second period of time to detect intrinsic electrical activity in the heart.
Claim 19
Independent Claim 96 words
A method for adjusting an implantable cardiac pacemaker comprising: generating electrical stimuli to be selectively delivered to a patient's heart, sensing electrical activity of said heart, amplifying sensed electrical activity, changing bandpass frequency characteristics during a cardiac cycle to a first predetermined low frequency range for a first period of time after delivery of a stimulus to said heart, detecting evoked electrical activity in the heart, and changing bandpass frequency characteristics during said cardiac cycle to a second predetermined high frequency range for a second period of time to detect intrinsic electrical activity in the heart.
Claim 20
Dependent Claim 31 words
The method for adjusting the implantable cardiac stimulator according to claim 17 further comprising adjusting the generation of said electrical stimuli responsive to the presence or absence of evoked electrical activity.
Claim 21
Dependent Claim 36 words
The method for adjusting the implantable cardiac pacemaker according to claim 18 wherein step of changing frequency characteristics comprises switching at least one capacitor into and out of connection with an amplifier at a selected frequency.
Claim 22
Dependent Claim 28 words
The method for adjusting the implantable cardiac pacemaker according to claim 19 wherein said step of changing the frequency characteristics further includes controlling said switching with a microprocessor.
Claim 23
Dependent Claim 43 words
The method for adjusting the implantable cardiac pacemaker according to claim 17 further comprising changing the gain of an amplifier to a first high gain during said first period of time and to a second low gain during said second period of time.
Claim 24
Dependent Claim 31 words
The method for adjusting the implantable cardiac stimulator according to claim 21 further comprising adjusting the generation of said electrical stimuli responsive to the presence or absence of evoked electrical activity.
Claim 25
Dependent Claim 37 words
The method for adjusting the implantable cardiac pacemaker according to claim 22 wherein the step of changing frequency characteristics comprises switching at least one capacitor into and out of connection with said amplifier at a selected frequency.
Claim 26
Dependent Claim 28 words
The method for adjusting the implantable cardiac pacemaker according to claim 23 wherein said step of changing the frequency characteristics further includes controlling said switching with a microprocessor.
Claim 27
Dependent Claim 32 words
The method for adjusting the implantable cardiac pacemaker according to claim 24 wherein said step of changing gain comprises selectively connecting at least one of a plurality of capacitors to said amplifier.
Claim 28
Dependent Claim 27 words
The method for adjusting the implantable cardiac pacemaker according to claim 25 wherein said selectively connecting step further comprises controlling selection of said capacitors with a microprocessor.
Claim 29
Dependent Claim 53 words
The method for adjusting the implantable cardiac pacemaker according to claim 21 further comprising changing the bandpass frequency characteristics of said amplifier to a third predetermined higher frequency range for a third period of time at lest immediately after delivery of said stimulus to the heart and before said first period of time.
Claim 30
Dependent Claim 31 words
The method for adjusting the implantable cardiac stimulator according to claim 27 further comprising adjusting the generation of said electrical stimuli responsive to the presence or absence of evoked electrical activity.
Claim 31
Dependent Claim 38 words
The method for adjusting the implantable cardiac pacemaker according to claim 28 wherein the step of selectively changing frequency characteristics comprises switching at least one capacitor into and out of connection with an amplifier at a selected frequency.
Claim 32
Dependent Claim 35 words
The method for adjusting the implantable cardiac pacemaker according to claim 29 wherein said step of selectively changing the frequency characteristics further includes controlling said switching of said at least one capacitor by a microprocessor.
Claim 33
Dependent Claim 32 words
The method for adjusting the implantable cardiac pacemaker according to claim 30 wherein said step of changing gain comprises selectively connecting at least some of a plurality of capacitors to said amplifier.
Claim 34
Dependent Claim 26 words
The method for adjusting the implantable cardiac pacemaker according to claim 31 wherein said step of selectively connecting further comprises controlling said capacitors with a microprocessor.

References Cited (Backward Citations)

US4261369A Cited
US4436093A Cited
US4381786A Cited
US4555668A Cited
US5024221A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-11-10 1996-05-11 1996-11-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-11-10 2000-05-11 2000-11-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-11-10 2004-05-11 2004-11-10 $7700.00 Window Closed / Lapsed

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