Method and system for patient-specific modeling of blood flow

• US 8,386,188 B2
• Filed: 01/27/2011
• Issued: 02/26/2013
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Heartflow Inc.
• Original Assignee: Heartflow Inc.
• Inventors: Taylor, Charles A., Fonte, Timothy A., Bai, Ying
• Primary Examiner(s): Clow, Lori A
• Application Number:
  US13/014,850
• Publication Number:
  US 20120041323A1
• Time in Patent Office: 761 Days
• Field of Search: None
• US Class Current: 702/19
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Abstract

Embodiments include a system for determining cardiovascular information for a patient. The system may include at least one computer system configured to receive patient-specific data regarding a geometry of the patient'"'"'s heart, and create a three-dimensional model representing at least a portion of the patient'"'"'s heart based on the patient-specific data. The at least one computer system may be further configured to create a physics-based model relating to a blood flow characteristic of the patient'"'"'s heart and determine a fractional flow reserve within the patient'"'"'s heart based on the three-dimensional model and the physics-based model.

Claims

1. A system for determining cardiovascular information for a patient, the system comprising:

at least one computer system configured to;

receive patient-specific data regarding a geometry of at least a portion of an anatomical structure of the patient, the anatomical structure including at least a portion of a plurality of arteries and myocardial tissue connected to at least some of the plurality of arteries;

create a three-dimensional model representing the anatomical structure of the patient based on the patient-specific data;

divide at least a portion of the three-dimensional model representing the myocardial tissue into segments; and

determine perfusion information associated with at least one of the segments based on the three-dimensional model and a physiological condition of the patient.

2. The system of claim 1, wherein the at least one computer system is further configured to determine the perfusion information by determining a blood flow into the at least one segment.

3. The system of claim 1, wherein the at least one computer system is further configured to:

subdivide at least one of the segments into subsegments; and

determine the perfusion information by determining a blood flow into at least one of the subsegments.

4. The system of claim 1, wherein the at least one computer system is further configured to subdivide the segments until a desired resolution is obtained.

5. The system of claim 1, wherein the at least one computer system is further configured to determine a size of the at least one segment based on a size of at least one of the arteries connected to the at least one segment.

6. The system of claim 1, wherein the physiological condition of the patient includes at least one of a cardiac output, a heart rate, a stroke volume, a blood pressure, a level of exercise or exertion, a level of hyperemia, or a medication for the patient.

7. The system of claim 1, wherein the at least one computer is further configured to prepare a three-dimensional simulation of the anatomical structure indicating the information regarding the perfusion information associated with a plurality of the segments.

8. The system of claim 7, wherein the at least one computer system is further configured to determine the perfusion information by determining a blood flow into respective segments, and variations in the blood flow into the respective segments are indicated by variations in color or shading.

9. The system of claim 1, wherein the at least one computer system is further configured to determine a location of the at least one segment based on a location of at least one artery of the plurality of arteries that is connected to the at least one segment.

10. The system of claim 1, wherein the plurality of arteries includes a plurality of coronary arteries emanating from the patient'"'"'s aorta.

11. The system of claim 1, wherein the patient-specific data includes computed tomography imaging data.

12. The system of claim 11, wherein:

the patient-specific data includes time-varying data regarding the geometry of at least the portion of the anatomical structure of the patient at different times; and

the at least one computer system is configured to create the three-dimensional model based on the time-varying data and determine the perfusion information based on the time-varying data.

13. The system of claim 1, wherein the at least one computer is further configured to determine the perfusion information by determining information relating to an amount of flow from an outlet of at least one artery of the plurality of arteries that is connected to a respective segment and by determining information relating to a volume of the respective segment.

14. The system of claim 13, wherein the at least one computer is further configured to determine the perfusion information by dividing the determined information relating to the amount of flow from the outlet of the at least one artery by the determined information relating to the volume of the respective segment.

15. A method for determining cardiovascular information for a patient using at least one computer system, the method comprising:

receiving, using at least one computer system, patient-specific data regarding a geometry of at least a portion of an anatomical structure of the patient, the anatomical structure including at least a portion of a plurality of arteries and myocardial tissue connected to at least some of the plurality of arteries;

creating, using the at least one computer system, a three-dimensional model representing the anatomical structure of the patient based on the patient-specific data;

extending, using the at least one computer system, the three-dimensional model to form an augmented model;

dividing, using the at least one computer system, at least a portion of the augmented model representing the myocardial tissue into segments; and

determining, using the at least one computer system, perfusion information associated with at least one of the segments based on the augmented model and a physiological condition of the patient.

16. The method of claim 15, wherein:

extending the three-dimensional model includes extending at least one of the arteries included in the three-dimensional model;

dividing the at least one portion of the augmented model includes dividing an extended portion of the at least one artery into segments; and

the perfusion information is associated with at least one of the segments of the extended portion.

17. The method of claim 15, wherein:

extending the three-dimensional model includes creating additional branches of arteries connected to at least one of the arteries included in the three-dimensional model;

dividing the at least one portion of the augmented model includes dividing at least one of the additional branches into segments; and

the perfusion information is associated with at least one of the segments of the at least one additional branch.

18. The method of claim 15, further comprising determining a size of the at least one segment based on a size of at least one of the arteries connected to the at least one segment.

19. The method of claim 15, further comprising determining a size of the segments based on sizes of a plurality of neighboring arteries connected to the respective segments.

20. The method of claim 15, wherein:

the three-dimensional model is extended such that at least one artery of the plurality of arteries included in the three-dimensional model is extended along or within the myocardial tissue.

21. The method of claim 15, wherein:

extending the three-dimensional model includes extending at least one of the arteries included in the three-dimensional model or creating additional branches of arteries connected to at least one of the arteries included in the three-dimensional model; and

the three-dimensional model is extended until a desired size of the at least one extended artery or the additional branches is obtained; and

at least the portion of the augmented model representing the myocardial tissue is divided until a desired segment size is obtained.

22. The method of claim 21, wherein:

the patient-specific data includes imaging data; and

the desired size of the at least one extended artery and the desired segment size depend on a resolution of the imaging data.

23. The method of claim 15, wherein the augmented model includes at least a portion of a coronary arterial tree on an epicardial surface.

24. A non-transitory computer readable medium for use on a computer system containing computer-executable programming instructions for performing a method for determining cardiovascular information for a patient, the method comprising:

receiving patient-specific data regarding a geometry of at least a portion of an anatomical structure of the patient, the anatomical structure including at least a portion of a plurality of arteries and myocardial tissue connected to at least some of the plurality of arteries;

creating a three-dimensional model representing the anatomical structure of the patient based on the patient-specific data;

dividing at least a portion of the three-dimensional model representing the myocardial tissue into segments; and

determining perfusion information associated with at least one of the segments based on the three-dimensional model and a physics-based model relating to the anatomical structure.

25. The non-transitory computer readable medium of claim 24, the method further comprising:

comparing the determined information with measured perfusion information at a plurality of locations in the anatomical structure; and

adjusting the three-dimensional model or the physics-based model in response to the comparison.

26. The non-transitory computer readable medium of claim 25, wherein:

the physics-based model includes at least one lumped parameter model representing a blood flow through boundaries of the three-dimensional model, and

the at least one lumped parameter model is adjusted based on the comparison.

27. The non-transitory computer readable medium of claim 25, wherein the three-dimensional model or the physics-based model is adjusted until a difference between the determined information and the measured information is below a threshold.

28. The non-transitory computer readable medium of claim 25, wherein:

the three-dimensional model is adjusted by extending the three-dimensional model until a difference between the determined information and the measured information is below a threshold.