Claims
- 1. An improved implantable defibrillator apparatus for producing a capacitive-discharge defibrillation waveform to be delivered through at least two electrodes adapted for implantation in a human patient, the implantable defibrillator apparatus including a self-contained human implantable housing having electrical connections to at least two electrodes adapted for implantation in the human patient, the implantable housing containing a waveform-generating capacitor means for storing an electrical charge, means for charging the waveform-generating capacitor means, and means for selectively discharging the electrical charge in the capacitor means through the at least two electrodes in response to a control signal from a means for sensing of a cardiac arrhythmia in the human patient, the improvement comprising:
- the means for selectively discharging including means for controlling the discharge of the capacitor means through the at least two electrodes to produce a defibrillation waveform comprising at least one electrical pulse having a predetermined optimum pulse duration that is set by the apparatus according to at least one pre-selected criterion selected from the set consisting of a fixed duration for the pulse waveform, a fixed tilt for truncation the pulse waveform, a minimum duration of the pulse waveform, a minimum tilt for the pulse waveform, and any combination thereof.
- 2. The apparatus of claim 1 wherein the at least one criterion for optimization of the pulse wave form is a fixed duration for the pulse wave form in those conditions where a predetermined resistance of the patient in a path through which the pulse must flow is low.
- 3. The apparatus of claim 2 wherein the resistance in the path through which the pulse must flow is less than 40 ohms.
- 4. The apparatus of claim 1 wherein the at least one criterion for determination of the pulse duration is a fixed tilt to signal truncation of the waveform where a predetermined resistance of the patient in a path through which the pulse must flow is low.
- 5. The apparatus of claim 4 wherein the resistance in the path through which the pulse must flow is greater than 60 ohms.
- 6. The apparatus of claim 1 wherein the at least one criterion for optimization of the pulse wave form is a combination of fixed duration and fixed tilt.
- 7. The apparatus of claim 6 wherein the combination of fixed duration and fixed tilt is selected to result in a shorter pulse duration as determined in comparison to the duration determined according to either a fixed pulse criterion or a fixed tilt criterion.
CROSS REFERENCES TO APPLICATIONS
This is a continuation of application Ser. No. 08/322,189, entitled OPTIMAL PULSE DEFIBRILLATOR, filed on Oct. 12, 1994 now U.S. Pat. No. 5,549,643.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
5215081 |
Ostroff |
Jun 1993 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
322189 |
Oct 1994 |
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