Method and system for image processing and patient-specific modeling of blood flow

• US 9,839,484 B2
• Filed: 08/26/2016
• Issued: 12/12/2017
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Heartflow Inc.
• Original Assignee: Heartflow Inc.
• Inventors: Taylor, Charles A.
• Primary Examiner(s): Rahmjoo, Manuchehr
• Application Number:
  US15/248,632
• Publication Number:
  US 20160371455A1
• Time in Patent Office: 473 Days
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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 computer-implemented method for determining a hemodynamic pressure quantity, the method comprising:

acquiring angiography data from a patient at a first physiological state of the patient, the first physiological state comprising a state of hyperemia, a state of rest, or a state of exercise, the angiography data comprising x-ray angiography data, magnetic resonance angiography data, and/or computed tomographic angiography data;

determining, by a processor, a first flow in a blood vessel of the patient based on the angiography data, wherein the first flow corresponds to the first physiological state of the patient;

determining, by the processor, a second flow in a blood vessel based on scaling the first flow by a numerical factor from the first physiological state to a second physiological state, the second physiological state comprising a state of hyperemia, a state of rest, or a state of exercise, wherein the second flow corresponds to the second physiological state of the patient that is different from the first physiological state of the patient;

determining, by the processor, the hemodynamic pressure quantity based on the second flow; and

reporting the hemodynamic pressure quantity.

2. The computer-implemented method of claim 1 wherein the hemodynamic pressure quantity comprises fractional flow reserve.

3. The computer-implemented method of claim 1 wherein at least a portion of the angiography data is acquired when the patient is at rest.

4. The computer-implemented method of claim 1 wherein at least a portion of the angiography data is acquired when the patient is in a state of hyperemia.

5. The computer-implemented method of claim 1 wherein the second flow comprises hyperemic flow.

6. The computer-implemented method of claim 1 wherein the blood vessel comprises a stenosis.

7. The computer-implemented method of claim 1 further comprising determining both the flow and a change in pressure.

8. The computer-implemented method of claim 1 wherein the angiography data is acquired only when the patient is at rest.

9. The computer-implemented method of claim 1 wherein the first physiological state comprises a rest state and wherein the second physiological state comprises a hyperemic state.

10. The computer-implemented method of claim 1 wherein acquiring angiography data from a patient is based on a contrast agent in the blood vessel.

11. The computer-implemented method of claim 1 further comprising modeling at least a portion of the blood vessel based on the angiography data.

12. The computer-implemented method of claim 1 wherein the first flow comprises a rest-state flow.

13. The computer-implemented method of claim 12 wherein determining the second flow comprises determining a hyperemic flow, wherein the hyperemic flow is derived from the rest-state flow.

14. A system for determining a hemodynamic pressure quantity, the system comprising:

a processor;

a non-transitory memory coupled to the processor;

first logic stored in the memory and executable by the processor to cause the processor to acquire angiography data from a patient at a first physiological state of the patient, the first physiological state comprising a state of hyperemia, a state of rest, or a state of exercise, the angiography data comprising x-ray angiography data, magnetic resonance angiography data, and/or computed tomographic angiography data;

second logic stored in the memory and executable by the processor to cause the processor to determine a flow as a scaled flow based on the angiography data, wherein the flow corresponds to a second physiological state of the patient that is different from the first physiological state of the patient, the second physiological state comprising a state of hyperemia, a state of rest, or a state of exercise;

third logic stored in the memory and executable by the processor to cause the processor to determine a change in pressure in a blood vessel of the patient based on the angiography data;

fourth logic stored in the memory and executable by the processor to cause the processor to determine the hemodynamic pressure quantity based on the flow and/or the change in pressure; and

a display configured to output the hemodynamic pressure quantity.

15. The system of claim 14 wherein the hemodynamic pressure quantity comprises fractional flow reserve.

16. The system of claim 14 further comprising fifth logic stored in the memory and executable by the processor to cause the processor to monitor a contrast agent in the blood vessel.

17. The system of claim 14 further comprising fifth logic stored in the memory and executable by the processor to cause the processor to model at least a portion of the blood vessel based on the angiography data.

18. A non-transitory computer readable storage medium having stored therein data representing instructions executable by a programmed processor for determining a hemodynamic pressure quantity, the storage medium comprising instructions for:

acquiring angiography data from a patient at a first physiological state of the patient, the first physiological state comprising a state of hyperemia, a state of rest, or a state of exercise, the angiography data comprising x-ray angiography data, magnetic resonance angiography data, and/or computed tomographic angiography data;

determining a flow based on the angiography data, wherein the flow corresponds to a second physiological state of the patient that is different from the first physiological state of the patient, the second physiological state comprising a state of hyperemia, a state of rest, or a state of exercise, the flow being derived by scaling another flow determined for the first physiological state;

determining a change in pressure in a blood vessel of the patient based on the angiography data;

determining the hemodynamic pressure quantity based on the flow and/or the change in pressure; and

outputting the hemodynamic pressure quantity.