Patent US1963670A successfully refreshed from Google Patents.
Patent US5978710A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5978710A Expired / Lapsed US ⏱️ 0.0 years remaining

Implantable cardiac stimulator with safe noise mode

Assignee: Intermedics Inc
•
Filing: 1998-01-23
•
Granted: 1999-11-02
•
Expires: 2018-01-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An implantable medical device for electrically stimulating the heart to beat generally includes a processor, a plurality of electrodes, a sense amplifier, a pulse generator, and a heart status monitor. The processor can determine when the patient has entered an environment of high electromagnetic interference. When this occurs, the processor forces the implantable device into a safe noise mode. While in the same noise mode (which preferably continues while the patient is experiencing the electromagnetic interference), the implantable device paces the heart on demand and inhibits pacing during the vulnerable period. The processor determines when the vulnerable period is occurring and when the heart needs to be paced by monitoring a status signal from the heart status monitor. The status signal generated by the heart status monitor preferably is not sensitive to the electromagnetic interference, and thus the processor can determine the bio-mechanical state of the heart during a cardiac cycle even in the face of high electromagnetic interference. The heart status monitor preferably includes an impedance measurement circuit, but may include any type of cardiac sensor that can generate a status signal from which the processor can determine the beginning and ending of the vulnerable period. Accordingly, even during a period of high electromagnetic interference, the implantable device can provide on demand pacing support to the patient.

Inventors

  • 👤 David Prutchi
  • 👤 Patrick J. Paul

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 20:39
CPC Classifications
A; A61; A61N; A61N1/00; A61N1/18; A61N1/32; A61N1/36; A61N1/362; A61N1/37; A61N1/3718; Y; Y10; Y10S; Y10S128/00; Y10S128/901

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 144 words
A medical device adapted to be implanted in the human body for electrically stimulating the heart to beat and adapted to operate in at least two modes of operation, said medical device comprising: a plurality of electrodes; a sense circuit coupled to the electrodes; a pulse generator coupled to the electrodes; and a heart status monitor including a processor, said heart status monitor coupled to at least two of said electrodes, and said heart status monitor generating a heart status signal indicative of the bio-mechanical state of the heart during a cardiac cycle; said processor receiving the heart status signal and determining when the medical device is in a high noise environment and changing the mode of operation of the medical device to a safe noise mode in which the processor determines the bio-mechanical state of the heart by monitoring the heart status signal.
Claim 2
Dependent Claim 144 words
A medical device adapted to be implanted in the human body for electrically stimulating the heart to beat and adapted to operate in at least two modes of operation, said medical device comprising: a plurality of electrodes; a sense circuit coupled to the electrodes; a pulse generator coupled to the electrodes; and a heart status monitor including a processor, said heart status monitor coupled to at least two of said electrodes, and said heart status monitor generating a heart status signal indicative of the bio-mechanical state of the heart during a cardiac cycle; said processor receiving the heart status signal and determining when the medical device is in a high noise environment and changing the mode of operation of the medical device to a safe noise mode in which the processor determines the bio-mechanical state of the heart by monitoring the heart status signal.
Claim 3
Dependent Claim 32 words
The medical device of claim 1 wherein said processor is coupled to said sense circuit and determines the bio-mechanical state of the heart by monitoring an output signal from the sense circuit.
Claim 4
Dependent Claim 31 words
The medical device of claim 2 wherein said processor discontinues monitoring the output signal from said sense circuit when the processor determines the medical device is in a high noise environment.
Claim 5
Dependent Claim 29 words
The medical device of claim 3 wherein said heart status monitor includes an impedance measurement circuit and said heart status signal is indicative of the impedance of the heart.
Claim 6
Dependent Claim 20 words
The medical device of claim 4 wherein said processor computes the impedance of the heart from the heart status signal.
Claim 7
Dependent Claim 28 words
The medical device of claim 5 wherein said cardiac cycle includes a vulnerable period of time and said processor determines said vulnerable period during said safe noise mode.
Claim 8
Dependent Claim 26 words
The medical device of claim 6 wherein said processor determines said vulnerable period from the impedance of the heart and inhibits pacing during said vulnerable period.
Claim 9
Dependent Claim 41 words
The medical device of claim 4 wherein the said heart status monitor includes a sensor that is adapted to respond to a cardiac parameter and that provides a sensor output signal to said processor that is indicative of said cardiac parameter.
Claim 10
Dependent Claim 28 words
The medical device of claim 8 wherein said cardiac cycle includes a vulnerable period of time and said processor determines said vulnerable period during said safe noise mode.
Claim 11
Dependent Claim 30 words
The medical device of claim 9 wherein said processor determines said vulnerable period from said sensor output signal during said safe noise mode and inhibits pacing during said vulnerable period.
Claim 12
Dependent Claim 13 words
The medical device of claim 10 wherein said sensor includes a pressure transducer.
Claim 13
Dependent Claim 13 words
The medical device of claim 10 wherein said sensor includes a flow transducer.
Claim 14
Dependent Claim 13 words
The medical device of claim 10 wherein said sensor includes a volume transducer.
Claim 15
Dependent Claim 14 words
The medical device of claim 10 wherein said sensor includes a cardiac sound transducer.
Claim 16
Dependent Claim 13 words
The medical device of claim 10 wherein said sensor includes an acceleration transducer.
Claim 17
Dependent Claim 109 words
An implantable medical device for electrically stimulating a human heart, including: a plurality of electrodes; a processor including a first mode and a second mode of operation; an impedance circuit coupled to said processor, for generating a status signal indicative of the heart's impedance; a pulse generator to stimulate the heart; and a sense circuit to process electrical signals from said electrodes; said processor changes the operation of said medical device from said first mode to said second mode during a high noise event, and during said second mode said processor monitors the status signal, determines when a vulnerable period is occurring and inhibits pacing during said vulnerable period.
Claim 18
Dependent Claim 109 words
An implantable medical device for electrically stimulating a human heart, including: a plurality of electrodes; a processor including a first mode and a second mode of operation; an impedance circuit coupled to said processor, for generating a status signal indicative of the heart's impedance; a pulse generator to stimulate the heart; and a sense circuit to process electrical signals from said electrodes; said processor changes the operation of said medical device from said first mode to said second mode during a high noise event, and during said second mode said processor monitors the status signal, determines when a vulnerable period is occurring and inhibits pacing during said vulnerable period.

References Cited (Backward Citations)

US4091818A Cited
US4516579A Cited
US4733667A Cited
US5031614A Cited
US4940052A Cited
US5010887A Cited
US5144949A Cited
US5269299A Cited
US5314453A Cited
US5531772A Cited
US5697958A Cited
US5817136A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-11-01 2003-05-03 2003-11-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-11-01 2007-05-03 2007-11-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-11-01 2011-05-03 2011-11-02 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag