Method and system for quantifying limitations in coronary artery blood flow during physical activity in patients with coronary artery disease

1. A system for determining an activity level recommendation for a patient, the system comprising:

at least one computer system configured to:

receive data describing a geometry of at least a portion of a patient's heart;

identify a cardiac event and a blood flow characteristic threshold value associated with the cardiac event;

determine a three-dimensional model representing the geometry of at least the portion of the patient's heart based on the received data;

determine a physics-based model of blood flow through the three-dimensional model, the physics-based model including a resistance of blood flow at the patient's myocardium simulated at a selected level of physical activity of the patient;

model the flow of blood through the three-dimensional model using the physics-based model of blood flow through the three-dimensional model simulated at the selected level of physical activity;

calculate, from the modeled flow of blood through the three-dimensional model simulated at the selected level of physical activity, a value of a blood flow characteristic within the patient's heart at the selected level of physical activity;

update the physics-based model of blood flow by iteratively reducing the resistance to blood flow at the patient's myocardium and recalculating the value of the blood flow characteristic through each updated physics-based model, until the recalculated value exceeds the blood flow characteristic threshold value associated with the cardiac event;

determine, based on one or more stored patient activities classified according to intensity level, a classification of patient activity intensity level corresponding to the physics-based model at which the recalculated value exceeded the blood flow characteristic threshold value associated with the cardiac event; and

generate an activity level recommendation based on the determined classification of the patient activity intensity level.

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

generate the activity level recommendation based on a risk of injury to the patient, the injury including stroke or myocardial infarction, or other injury.

3. The system of claim 2 , wherein the at least one computer system is further configured to:

quantify the risk of the stroke, myocardial infarction, or other injury.

4. The system of claim 1 , wherein the activity level recommendation includes a level of physical activity of an intensity level less than the determined classification of the patient activity intensity level.

5. The system of claim 1 , wherein the blood flow characteristic is chosen from coronary blood flow, blood pressure, plaque stress, myocardial perfusion, blood flow affecting plaque vulnerability, or blood flow resulting from a location in the patient's heart comprising a territory of the patient's heart at risk of insufficient blood flow.

6. The system of claim 1 , wherein the selected level of physical activity is chosen from aerobic activity and anaerobic activity.

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

generate the activity level recommendation relative to a patient activity intensity level corresponding to wherein the selected level of physical activity comprises intimacy.

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

update the activity level recommendation based on a change in the value of the blood flow characteristic over time.

9. The system of claim 8 , wherein the blood flow characteristic threshold value is derived from a normal state value of the patient or from subjects of similar age and/or fitness level to the patient.

10. The system of claim 1 , wherein the three-dimensional model representing the geometry of at least the portion of the patient's heart based on the received data includes at least a portion of an aorta and at least a portion of a plurality of coronary arteries emanating from the portion of the aorta.

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

determine a location of a functionally significant narrowing in a coronary artery of the patient's heart based on the recalculated value of the at least one blood flow characteristic.

12. A method for determining an activity level recommendation for a patient, the method comprising:

receiving data describing a geometry of at least a portion of a patient's heart;

identifying a cardiac event and a blood flow characteristic threshold value associated with the cardiac event;

determining a three-dimensional model representing the geometry of at least the portion of the patient's heart based on the received data;

determining, using the at least one computer system, a physics-based model of blood flow through the three-dimensional model, the physics-based model including a resistance of blood flow at the patient's myocardium; simulated at a selected level of physical activity of the patient;

modeling the flow of blood through the three-dimensional model using the physics-based model of blood flow through the three-dimensional model simulated at the selected level of physical activity;

calculating, from the modeled flow of blood through the three-dimensional model simulated at the selected level of physical activity, a value of a blood flow characteristic within the patient's heart at the selected level of physical activity;

updating the physics-based model of blood flow by iteratively reducing the resistance to blood flow at the patient's myocardium and recalculating the value of the blood flow characteristic through each updated physics-based model, until the recalculated value exceeds the blood flow characteristic threshold value associated with the cardiac event;

determining, based on one or more stored patient activities classified according to intensity level, a classification of patient activity intensity level corresponding to the physics-based model at which the recalculated value exceeded the blood flow characteristic threshold value associated with the cardiac event; and

generating an activity level recommendation based on the determined classification of the patient activity intensity level.

13. The method of claim 12 , wherein the method further comprises:

generating the activity level recommendation based on a risk of injury to the patient, the injury including stroke or myocardial infarction, or other injury.

14. The method of claim 13 , wherein the method further comprises:

quantifying the risk of the stroke, myocardial infarction, or other injury.

15. The method of claim 12 , wherein the activity level recommendation includes a level of physical activity of an intensity level less than the determined classification of the patient activity intensity level.

16. The method of claim 12 , wherein the blood flow characteristic is chosen from coronary blood flow, blood pressure, plaque stress, myocardial perfusion, blood flow affecting plaque vulnerability, or blood flow resulting from a location in the patient's heart comprising a territory of the patient's heart at risk of insufficient blood flow.

17. The method of claim 12 , wherein the selected level of physical activity is chosen from aerobic activity and anaerobic activity.

18. The method of claim 12 , wherein the method further comprises:

generating the activity level recommendation relative to a patient activity intensity level corresponding to intimacy.

19. The method of claim 12 , wherein the method further comprises:

updating the activity level recommendation based on a change in the value of the blood flow characteristic over time.

20. The method of claim 19 , wherein the blood flow characteristic threshold value is derived from a normal state value of the patient or from subjects of similar age and/or fitness level to the patient.

21. The method of claim 14 , wherein the method further comprises:

determining a location of a functionally significant narrowing in a coronary artery of the patient's heart based on the recalculated value of the at least one blood flow characteristic.

22. The method of claim 12 , wherein the three-dimensional model representing the geometry of at least the portion of the patient's heart based on the received data includes at least a portion of an aorta and at least a portion of a plurality of coronary arteries emanating from the portion of the aorta.

23. A non-transitory computer readable medium for use on at least one computer system containing computer-executable programming instructions for determining an activity level recommendation for a patient, the method comprising:

receiving data describing a geometry of at least a portion of a patient's heart;

identifying a cardiac event and a blood flow characteristic threshold value associated with the cardiac event;

determining a three-dimensional model representing the geometry of at least the portion of the patient's heart based on the received data;

determining a physics-based model of blood flow through the three-dimensional model, the physics-based model including a resistance of blood flow at the patient's myocardium; simulated at a selected level of physical activity of the patient;

modeling the flow of blood through the three-dimensional model using the physics-based model of blood flow;

calculating, from the modeled flow of blood through the three-dimensional model simulated at the selected level of physical activity, a value of a blood flow characteristic within the patient's heart at the selected level of physical activity;

updating the physics-based model of blood flow by iteratively reducing the resistance to blood flow at the patient's myocardium and recalculating the value of the blood flow characteristic through each updated physics-based model, until the recalculated value exceeds the blood flow characteristic threshold value associated with the cardiac event;

determining, based on one or more stored patient activities classified according to intensity level, a classification of patient activity intensity level corresponding to the physics-based model at which the recalculated value exceeded the blood flow characteristic threshold value associated with the cardiac event; and

generating an activity level recommendation based on determined classification of the patient activity intensity level.

24. The non-transitory computer readable medium of claim 23 , wherein the method further comprises:

generating the activity level recommendation based on a risk of injury to the patient, the injury including stroke or myocardial infarction, or other injury.

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

quantifying the risk of the stroke, myocardial infarction, or other injury.

26. The non-transitory computer readable medium of claim 23 , wherein the activity level recommendation includes a level of physical activity of an intensity level less than the determined classification of the patient activity intensity level.

27. The non-transitory computer readable medium of claim 23 , where the blood flow characteristic is chosen from coronary blood flow, blood pressure, plaque stress, myocardial perfusion, blood flow affecting plaque vulnerability, or blood flow resulting from a location in the patient's heart comprising a territory of the patient's heart at risk of insufficient blood flow.

28. The non-transitory computer readable medium of claim 23 , wherein the selected level of physical activity is chosen from aerobic activity and anaerobic activity.

29. The non-transitory computer readable medium of claim 23 , wherein the method further comprises:

generating the activity level recommendation relative to a patient activity intensity level corresponding to intimacy.

30. The non-transitory computer readable medium of claim 23 , wherein the blood flow characteristic threshold value is derived from a normal state value of the patient or from subjects of similar age and/or fitness level to the patient.