PRESSURE RECOVERY INDEX TO ASSESS CARDIAC FUNCTION

• US 20090209869A1
• Filed: 02/17/2009
• Published: 08/20/2009
• Est. Priority Date: 02/18/2008
• Status: Active Grant

• Current Assignee: Washington University In St Louis
• Original Assignee: Washington University In St Louis
• Inventors: Zhang, Wei, Chung, Charles, Kovacs, Sandor J., Shmuylovich, Leonid
• Granted Patent: US 8,273,029 B2
• Time in Patent Office: Days
• US Class Current: 600/486
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders

Abstract

Determining an index for assessing cardiac function. In an embodiment, a method includes receiving ventricular pressure data during an invasive cardiac procedure, wherein the received pressure data includes a diastatic ventricular pressure value, a minimum ventricular pressure value, and a predefined fiducial marker pressure value. An index value is calculated by comparing a first pressure difference to a second pressure difference. The first pressure difference represents the difference between the received diastatic ventricular pressure value and the received minimum ventricular pressure value. The second pressure difference represents the difference between the received fiducial marker pressure value and the received minimum ventricular pressure value. The index value is provided to a health care provider to assess early diastolic cardiac function.

Claims

1. A method comprising:

receiving ventricular pressure data during an invasive cardiac procedure, said received pressure data comprising a diastatic ventricular pressure value, a minimum ventricular pressure value, and a predefined fiducial marker pressure value;

determining a first pressure difference between the received diastatic ventricular pressure value and the received minimum ventricular pressure value;

determining a second pressure difference between the received fiducial marker pressure value and the received minimum ventricular pressure value;

comparing the first pressure difference with the second pressure difference to generate an index value indicative of early diastolic cardiac function; and

providing the generated index value to a health care provider to assess cardiac function.

2. The method of claim 1, wherein said determining the first pressure difference, said determining the second pressure difference, said comparing, and said providing occur during or after the invasive cardiac procedure to enable the health care provided to dynamically assess cardiac function.

3. The method of claim 1, wherein the fiducial marker pressure value corresponds to one or more of the following:

an end diastolic pressure value, and a pressure value at the steepest slope of a pressure contour derived from the ventricular pressure data.

4. The method of claim 1, wherein receiving the ventricular pressure data comprises receiving left ventricular pressure data sampled over time.

5. The method of claim 1, wherein the generated index is indicative of one or more of the following:

ventricular diastolic function, ventricular viscoelasticity, ventricular relaxation, presence or absence of a delayed relaxation pattern, valvular function, ventricular efficiency, and ventricular energetics.

6. The method of claim 1, wherein receiving the ventricular pressure data comprises receiving running averages of each of the diastatic ventricular pressure value, the minimum ventricular pressure value, and the predefined fiducial marker pressure value.

7. The method of claim 1, further comprising:

storing the generated index;

receiving additional ventricular pressure data;

determining the first and second pressure differences as a function of the received additional ventricular pressure data;

comparing the first and second pressure differences to generate another index value;

averaging the index value and the other index value; and

providing the averaged index value to the health care provider.

8. The method of claim 1, wherein comparing the first pressure difference with the second pressure difference comprises calculating a ratio of the first pressure difference to the second pressure difference.

9. A system comprising:

a memory area for storing ventricular pressure data obtained during an invasive cardiac procedure, said ventricular pressure data comprising a diastatic ventricular pressure value, a minimum ventricular pressure value, and a predefined fiducial marker pressure value; and

a processor configured to execute computer-executable instructions for;

determining a first pressure difference between the diastatic ventricular pressure value and the minimum ventricular pressure value stored in the memory area;

determining a second pressure difference between the fiducial marker pressure value and the minimum ventricular pressure value;

comparing the first pressure difference with the second pressure difference to generate an index value indicative of early diastolic cardiac function; and

calculating parameters of an echocardiogram waveform corresponding to the ventricular pressure data stored in the memory area as a function of the generated index value and the ventricular pressure data stored in the memory area.

10. The system of claim 9, further comprising:

means for obtaining the ventricular pressure data for storage in the memory area; and

means for defining the fiducial marker pressure value.

11. The system of claim 9, further comprising means for generating the index value as a function of the first and second pressure differences.

12. The system of claim 9, further comprising means for calculating the parameters of the echocardiogram waveform.

13. The system of claim 9, wherein the generated index corresponds to a pressure recovery ratio.

14. The system of claim 9, wherein the first pressure difference represents recovered pressure during early filling of the ventricle, and the second pressure difference represents lost pressure during early filling of the ventricle.

15. The system of claim 9, wherein the processor is further configured to execute computer-executable instructions for plotting the echocardiogram waveform based on the calculated parameters.

16. The system of claim 9, wherein the processor is further configured to execute computer-executable instructions for calculating a damping constant for the echocardiogram waveform as a function of the generated index value.

17. The system of claim 9, wherein the processor is further configured to execute computer-executable instructions for calculating an initial upslope for the echocardiogram waveform as a function of the determined second pressure difference.

18. The system of claim 9, wherein the processor is further configured to execute computer-executable instructions for calculating a frequency of the echocardiogram waveform as a function of one or more of the following:

an estimated echocardiogram waveform start time, an estimated echocardiogram waveform end time, and an estimated echocardiogram waveform peak time.

19. One or more computer-readable media having computer-executable components, said components comprising:

a memory component for accessing ventricular pressure data stored during an invasive cardiac procedure, said ventricular pressure data comprising a diastatic ventricular pressure value, a minimum ventricular pressure value, and a predefined fiducial marker pressure value;

a processor component for determining a first pressure difference between the diastatic ventricular pressure value and the minimum ventricular pressure value accessed by the memory component, said processor component further determining a second pressure difference between the fiducial marker pressure value and the minimum ventricular pressure value accessed by the memory component;

an index component for calculating a ratio of the first pressure difference to the second pressure difference to generate a dimensionless index value indicative of early diastolic cardiac function; and

an interface component for providing the index value calculated by the index component to a health care provider to assess cardiac function.

20. The computer-readable media of claim 19, wherein the fiducial marker pressure value corresponds to one or more of the following:

an end diastolic pressure value, and a pressure value at the steepest slope of a pressure contour derived from the ventricular pressure data.