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US4809681A
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Electrocardiographic measurement method for controlling an intra-aortic balloon pump
Assignee: Aisin Corp
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Filing: 1987-03-30
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Granted: 1989-03-07
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Expires: 2007-03-30
Abstract
Abstract A pair of spaced electrodes are disposed inside the thoracic aorta near the heart and are used to sense R- and P-waves in an ECG signal. The electrodes are moved to an ideal intra-aortic position, which is that where R- and P-waves are sensed to have the same magnitude, the P-wave, which occurs earlier than the R-wave, serving as means for accurately predicting the occurrence of the R-wave. The electrodes are affixed to the distal end of an intra-aortic balloon, which is capable of being disposed at the ideal position by monitoring of the R- and P-waves sensed by the electrodes. The balloon is deflated at the occurrence of the R-wave, which has been correctly predicted by the earlier P-wave.
Inventors
- 👤 Adrian Kantrowitz
- 👤 Paul S. Freed
- 👤 Hiroyuki Tachi
- 👤 Akira Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:22
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/68; A61B5/6846; A61B5/6847; A61B5/6852; A61B5/6853; A61B5/02; A61B5/021; A61B5/0215; A61B5/24; A61B5/25; A61B5/279; A61B5/28; A61B5/283; A61M; A61M29/00; A61M29/02; A61M60/00; A61M60/10; A61M60/122; A61M60/126; A61M60/135; A61M60/139; A61M60/20; A61M60/295; A61M60/40; A61M60/497; A61M60/50; A61M60/508; A61M60/515; A61M2205/00; A61M2205/33; A61M2205/3303
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
122 words
An electrocardiographic measurement method for assistance in controlling deflation of an intra-aortic balloon pump disposed in the thoracic aorta of a patient, comprising the steps of: disposing at least a pair of spaced electrodes inside the thoracic aorta near the patient's heart; sensing R-waves and P-waves by said electrodes; moving said electrodes to a position in the thoracic aorta where the R- and P-waves are substantially equal in magnitude for accurately detecting the occurrence of the P-wave; predicting subsequent occurrences of the R-waves in accordance with the detected occurrences of the P-waves; and initiating deflation of the intra-aortic balloon pump in accordance with the predicted subsequent occurrences of the R-waves such that the balloon pump is deflated synchronously with each R-wave occurrence.
Claim 2
Dependent Claim
122 words
An electrocardiographic measurement method for assistance in controlling deflation of an intra-aortic balloon pump disposed in the thoracic aorta of a patient, comprising the steps of: disposing at least a pair of spaced electrodes inside the thoracic aorta near the patient's heart; sensing R-waves and P-waves by said electrodes; moving said electrodes to a position in the thoracic aorta where the R- and P-waves are substantially equal in magnitude for accurately detecting the occurrence of the P-wave; predicting subsequent occurrences of the R-waves in accordance with the detected occurrences of the P-waves; and initiating deflation of the intra-aortic balloon pump in accordance with the predicted subsequent occurrences of the R-waves such that the balloon pump is deflated synchronously with each R-wave occurrence.
Claim 3
Dependent Claim
99 words
The electrocardiographic method according to claim 1, wherein the step of moving said electrodes include the substeps of: inserting the electrodes into a deeper region in the thoracic aorta when the R-wave is larger than the P-wave at a first present position in the thoracic aorta; withdrawing the electrodes into a shallower region in the thoracic aorta when the R-wave and P-wave change polarity at a second present position in the thoracic aorta; and determining a position intermediate said first and second present positions in the thoracic aorta at which the R- and P-waves are substantially equal in magnitude.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-03-06 | 1992-09-05 | 1993-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-06 | 1996-09-05 | 1997-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-06 | 2000-09-05 | 2001-03-07 | $7700.00 | Window Closed / Lapsed |