Method and system for patient-specific modeling of blood flow

• US 9,268,902 B2
• Filed: 06/16/2014
• Issued: 02/23/2016
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Heartflow Inc.
• Original Assignee: Heartflow Inc.
• Inventors: Taylor, Charles A., Choi, Gilwoo
• Primary Examiner(s): Clow, Lori A
• Application Number:
  US14/305,671
• Publication Number:
  US 20140355859A1
• Time in Patent Office: 617 Days
• Field of Search: None
• US Class Current: 1/1
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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 image data regarding a geometry of an anatomical structure of the patient, the anatomical structure including at least a portion of at least one coronary artery emanating from an aorta;

create a three-dimensional model representing at least the portion of the at least one coronary artery using the received patient-specific image data;

determine a blood flow model defining the flow of blood through the three-dimensional model representing at least the portion of the at least one coronary artery;

calculate one or more values of a blood flow characteristic within the portion of the at least one coronary artery using by modeling blood flow through the three-dimensional model using the determined blood flow model, where the blood flow model is a function of the three-dimensional model;

calculate at least one of;

(i) a risk of plaque rupture within the portion of the at least one coronary artery using the modeled blood flow through the three-dimensional model and the one or more calculated values of the blood flow characteristic, and (ii) a risk of perfusion deficit within at least a portion of the anatomical structure of the patient using the modeled blood flow through the three-dimensional model and the one or more calculated values of the blood flow characteristic; and

display on the three-dimensional model representing at least the portion of the at least one coronary artery, a visual representation associated with at least one of;

(i) the calculated risk of plaque rupture within the portion of the at least one coronary artery, and (ii) the calculated risk of perfusion deficit within at least the portion of the anatomical structure.

2. The system of claim 1, wherein the visual representation includes a map of at least one plaque at risk of rupture at a plurality of locations in the portion of the at least one coronary artery.

3. The system of claim 1, wherein the at least one computer system is configured to calculate the at least one of the risk of plaque rupture and the risk of perfusion deficit based on at least one of a calculated traction force, a pressure gradient, a fractional flow reserve, and a ratio of plaque stress to a plaque strength.

4. The system of claim 1, wherein the at least one computer system is configured to calculate the at least one of the risk of plaque rupture and the risk of perfusion deficit based on at least one of hemodynamic stress, stress frequency, and stress direction.

5. The system of claim 1, wherein the at least one computer system is configured to calculate the at least one of the risk of plaque rupture and the risk of perfusion deficit based on plaque properties chosen from at least one of plaque strength, plaque density, plaque size, plaque composition, and plaque type.

6. The system of claim 1, wherein the at least one computer system is further configured to identify one or more segments of myocardial tissue that would be affected by the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit.

7. The system of claim 6, wherein the visual representation associated with the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit further includes the one or more segments of myocardial tissue that would be affected by the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit.

8. The system of claim 1, wherein the at least one computer system is further configured to assess the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit under simulated physiological conditions.

9. The system of claim 8, wherein the simulated physiological conditions are chosen from rest and exercise.

10. The system of claim 1, wherein the at least one computer system is configured to calculate the risk of plaque rupture by calculating the risk as a ratio of simulated plaque stress to an estimated plaque strength.

11. The system of claim 10, wherein the plaque strength is estimated using material composition data derived from CCTA or MRI.

12. The system of claim 1, wherein the at least one computer system is configured to calculate the risk of perfusion deficit by identifying one or more myocardial segments as having a high probability of low perfusion due to the risk of rupture of at least one plaque.

13. The system of claim 1, wherein the at least one computer system is further configured to calculate a plaque rupture vulnerability index based on at least one of total hemodynamic stress, stress frequency, stress direction, and plaque strength.

14. The system of claim 1, wherein the at least one computer system is further configured to determine at least one location where at least one plaque at risk of rupture may create an impediment to flow by comparing a size of the at least one plaque at risk of rupture to a size of one or more downstream vessels.

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

receiving, at a computer system, patient-specific image data regarding a geometry of an anatomical structure of a patient, the anatomical structure including at least a portion of at least one coronary artery emanating from an aorta;

creating, using the computer system, a three-dimensional model representing at least the portion of the at least one coronary artery using the received patient-specific image data;

determining, using the computer system, a blood flow model defining the flow of blood through the three-dimensional model representing at least the portion of the at least one coronary artery;

calculating, using the computer system, one or more values of a blood flow characteristic within the portion of the at least one coronary artery using by modeling blood flow through the three-dimensional model using the determined blood flow model, where the blood flow model is a function of the three-dimensional model;

calculating, using the computer system, at least one of;

(i) a risk of plaque rupture within the portion of the at least one coronary artery using the modeled blood flow through the three-dimensional model and the one or more calculated values of the blood flow characteristic, and (ii) a risk of perfusion deficit within at least a portion of the anatomical structure of the patient using the modeled blood flow through the three-dimensional model and the one or more calculated values of the blood flow characteristic; and

displaying on the three-dimensional model, using the computer system, representing at least the portion of the at least one coronary artery, a visual representation associated with at least one of;

(i) the calculated risk of plaque rupture within the portion of the at least one coronary artery, and (ii) the calculated risk of perfusion deficit within at least the portion of the anatomical structure.

16. The method of claim 15, wherein the visual representation includes a map of at least one plaque at risk of rupture at a plurality of locations in the at least one coronary artery.

17. The method of claim 15, wherein the at least one of the risk of plaque rupture and the risk of perfusion deficit is calculated based on at least one of a calculated traction force, a pressure gradient, a fractional flow reserve, and a ratio of plaque stress to a plaque strength.

18. The method of claim 15, wherein the at least one of the risk of plaque rupture and the risk of perfusion deficit is calculated based on at least one of hemodynamic stress, stress frequency, and stress direction.

19. The method of claim 15, wherein the at least one of the risk of plaque rupture and the risk of perfusion deficit is calculated based on plaque properties chosen from at least one of plaque strength, plaque density, plaque size, plaque composition, and plaque type.

20. The method of claim 15, further comprising identifying one or more segments of myocardial tissue that would be affected by the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit.

21. The method of claim 20, wherein the visual representation further includes the one or more segments of myocardial tissue that would be affected by the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit.

22. The method of claim 15, further comprising assessing the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit under simulated physiological conditions.

23. The method of claim 22, wherein the simulated physiological conditions are chosen from rest and exercise.

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

receiving patient-specific image data regarding a geometry of an anatomical structure of the patient, the anatomical structure including at least a portion of at least one coronary artery emanating from an aorta;

creating a three-dimensional model representing at least the portion of the at least one coronary artery using the received patient-specific image data;

determining, using the computer system, a blood flow model defining the flow of blood through the three-dimensional model representing at least the portion of the at least one coronary artery;

calculating one or more values of a blood flow characteristic within the portion of the at least one coronary artery using by modeling blood flow through the three-dimensional model using the determined blood flow model, where the blood flow model is a function of the three-dimensional model;

calculating at least one of;

(i) a risk of plaque rupture within the portion of the at least one coronary artery using the modeled blood flow through the three-dimensional model and the one or more calculated values of the blood flow characteristic, and (ii) a risk of perfusion deficit within at least a portion of the anatomical structure of the patient using the modeled blood flow through the three-dimensional model and the one or more calculated values of the blood flow characteristic; and

displaying on the three-dimensional model representing at least the portion of the at least one coronary artery, a visual representation associated with at least one of;

(i) the calculated risk of plaque rupture within the portion of the at least one coronary artery, and (ii) the calculated risk of perfusion deficit within at least the portion of the anatomical structure.

25. The non-transitory computer readable medium of claim 24, wherein the visual representation includes a map of at least one plaque at risk of rupture at a plurality of locations in the at least one coronary artery.

26. The non-transitory computer readable medium of claim 24, wherein the at least one of the risk of plaque rupture and the risk of perfusion deficit is calculated based on at least one of a calculated traction force, a pressure gradient, a fractional flow reserve, and a ratio of plaque stress to a plaque strength.

27. The non-transitory computer readable medium of claim 24, wherein the at least one of the risk of plaque rupture and the risk of perfusion deficit is calculated based on at least one of hemodynamic stress, stress frequency, and stress direction.

28. The non-transitory computer readable medium of claim 24, wherein the at least one of the risk of plaque rupture and the risk of perfusion deficit is calculated based on plaque properties chosen from at least one of plaque strength, plaque density, plaque size, plaque composition, and plaque type.

29. The non-transitory computer readable medium of claim 28, wherein the visual representation associated with the at least one of the calculated risk of plaque rupture and the calculated risk of perfusion deficit further includes the one or more segments of myocardial tissue that would be affected by the at least one of the calculated risk of rupture and the calculated risk of perfusion deficit.

30. The non-transitory computer readable medium of claim 24, wherein the method further comprises identifying one or more segments of myocardial tissue that would be affected by the at least one of the calculated risk of rupture and the calculated risk of perfusion deficit.