US4877035A
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Measurement of the end-systolic pressure-volume relation using intraaortic balloon occlusion
Assignee: University of Pennsylvania
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Filing: 1988-10-12
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Granted: 1989-10-31
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Expires: 2008-10-12
Abstract
Abstract Novel, noninvasive in vivo methods and apparatus for measuring the end-systolic pressure-volume relation and deriving peak end-systolic elastance, Emax, which do not alter intrinsic or reflex-stimulated cardiac contractility are disclosed. Afterload is varied by the controlled inflation of an intraaortic balloon catheter positioned in the ascending aorta. Balloon inflation is timed to transiently interrupt ventricular ejection at different times during the ejection phase, producing contraction at different ventricular volumes. Simultaneous measurements of left ventricular pressure and aortic volume during the occlusion sequence allows pressure vs. ejected volume loops to be generated, from which the slope of the end-systolic pressure-volume relationship, Emax is determined. Emax was measured in 6 Dorsett sheep with normal, enhanced, and depressed contractile states. In the normal states, Emax ranged from 1.01 to 5.08 mmHg/ml in animals with body weights ranging from 23 to 32 kg. This data was not significantly different (p>0.05) from the Emax-body weight curve compiled from other measurements of Emax, After epinephrine infusion, Emax increased from 3.07+/-1.49 to 5.79+/-1.97 mmHg/ml, consistent with previous investigations. Furthermore, serial measurements of Emax tracked cardiac function even in severely depressed hearts or other biological pumps with rapidly changing contractility.
Inventors
- 👤 Daniel Bogen
- 👤 Krishanu Gupta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:25
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/021; A61B5/0215; A61B5/026; A61B5/029
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
132 words
A method of determining an index of the global ventricular contractility of a biological pump, comprising the steps of: (a) acquiring data representative of ventricular pressure and data representative of ventricular volume of the biological pump during at least one beat of the biological pump; (b) transiently altering the hemodynamic load of the biological pump; (c) acquiring data representative of ventricular pressure and data representative of ventricular volume of the biological pump during at least one beat of the biological pump while the biological pump is in the altered hemodynamic state; (d) identifying the pressure and volume data value associated with the end-systolic point of the beats the biological pump of steps (a) and (c); and (e) relating the data identified in step (d) to the end-systolic elastance of the biological pump.
Claim 2
Independent Claim
132 words
A method of determining an index of the global ventricular contractility of a biological pump, comprising the steps of: (a) acquiring data representative of ventricular pressure and data representative of ventricular volume of the biological pump during at least one beat of the biological pump; (b) transiently altering the hemodynamic load of the biological pump; (c) acquiring data representative of ventricular pressure and data representative of ventricular volume of the biological pump during at least one beat of the biological pump while the biological pump is in the altered hemodynamic state; (d) identifying the pressure and volume data value associated with the end-systolic point of the beats the biological pump of steps (a) and (c); and (e) relating the data identified in step (d) to the end-systolic elastance of the biological pump.
Claim 3
Dependent Claim
17 words
The method of claim 1, wherein said transiently altered hydrodynamic load is initiated by a variable afterload.
Claim 4
Dependent Claim
17 words
The method of claim 2, wherein said varying afterload is produced by intermittent blockage of the aorta.
Claim 5
Dependent Claim
22 words
The method of claim 3, wherein said intermittent blockage of the aorta is produced by the inflation of an intraaortic balloon catheter
Claim 6
Dependent Claim
35 words
The method of claim 4, wherein said inflation of an intraaortic balloon catheter is timed to transiently interrupt ventricular ejection at different times during the ejection phase, to produce isovolumic contraction at differing ventricular volumes.
Claim 7
Dependent Claim
27 words
The method of claim 1, wherein steps (b) and (c) are repeated to acquire a plurality of data sets, each associated with a different altered hemodynamic load.
Claim 8
Dependent Claim
35 words
The method of claim 1, wherein step (e) is further comprised of: performing a linear regression to determine the slope of a line connecting the end-systolic pressure and volume data pairs identified in step (d).
Claim 9
Dependent Claim
113 words
Apparatus for determining an index of global ventricular contractility of a biological pump, comprising: (a) means for transiently and intermittently occluding the aorta of a biological pump; (b) means for acquiring data representative of ventricular pressure of the biological pump; (c) means for acquiring data representative of ventricular volume of the biological pump; (d) means for monitoring the data representative of ventricular pressure and determining if said ventricular pressure has reached a specified value; (e) means for transmitting a control signal, said control signal being transmitted upon said ventricular pressure reaching said specified value; and (f) means for actuating said means for occluding an aorta, said actuation means governed by said control signal.
Claim 10
Dependent Claim
113 words
Apparatus for determining an index of global ventricular contractility of a biological pump, comprising: (a) means for transiently and intermittently occluding the aorta of a biological pump; (b) means for acquiring data representative of ventricular pressure of the biological pump; (c) means for acquiring data representative of ventricular volume of the biological pump; (d) means for monitoring the data representative of ventricular pressure and determining if said ventricular pressure has reached a specified value; (e) means for transmitting a control signal, said control signal being transmitted upon said ventricular pressure reaching said specified value; and (f) means for actuating said means for occluding an aorta, said actuation means governed by said control signal.
Claim 11
Dependent Claim
60 words
The apparatus of claim 8, wherein said means for transiently and intermittently occluding the aorta of a biological pump is comprised of: (a) intraaortic balloon catheter; (b) means for inflating said balloon catheter; (c) means for controlling the amount of inflation of said balloon catheter and (d) means for inflating said balloon catheter at designated times within a cardiac cycle.
Claim 12
Dependent Claim
16 words
The apparatus of claim 8, wherein said means for determining ventricular pressure is a catheter-tip manometer.
Claim 13
Dependent Claim
17 words
The apparatus of claim 8, wherein said means for determining aortic volume is an electromagnetic flow probe.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-30 | 1993-05-01 | 1993-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-30 | 1997-05-01 | 1997-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-30 | 2001-05-01 | 2001-10-31 | $7700.00 | Window Closed / Lapsed |