Method for determining cardiovascular information
View Patent ↗A noninvasive patient-specific method is provided to aid in the analysis, diagnosis, prediction or treatment of hemodynamics of the cardiovascular system of a patient. Coronary blood flow and pressure can be predicted using a 3-D patient image-based model that is implicitly coupled with a model of at least a portion of the remaining cardiovascular system. The 3-D patient image-based model includes at least a portion of the thoracic aorta and epicardial coronaries of the patient. The shape of one or more velocity profiles at the interface of the models is enforced to control complex flow features of recirculating or retrograde flow thereby minimizing model instabilities and resulting in patient-specific predictions of coronary flow rate and pressure. The invention allows for patient-specific predictions of the effect of different or varying physiological states and hemodynamic benefits of coronary medical interventions, percutaneous coronary interventions and surgical therapies.
1. A method for determining cardiovascular information for a patient, the method comprising:
receiving, using at least one computer system, patient-specific image data representing a first portion of a cardiovascular structure generated using non-invasive imaging techniques, wherein the first portion includes at least one coronary artery emanating from the patient's aorta;
receiving, using at least one computer system, patient-specific image data representing a second portion of the cardiovascular structure generated using non-invasive imaging techniques, wherein the second portion includes at least one coronary artery located downstream from the first portion;
creating, using at least one computer system, a three-spatial-dimension model of the first portion of the cardiovascular structure using the patient-specific image data, wherein the three-spatial-dimension model is associated with a first set of fluid dynamics equations representing the flow of fluid through the cardiovascular structure and comprising one or more parameters for blood flow rate, coronary blood pressure, and/or vessel wall displacement;
receiving, using at least one computer system, vessel morphology data generated using non-invasive imaging techniques;
receiving, using at least one computer system, at least one non-patient-specific resistance parameter value;
creating, using at least one computer system, a lumped-parameter coronary vascular model of the second portion of the cardiovascular structure using the vessel morphology data and the at least one non-patient-specific resistance parameter value, wherein the lumped-parameter coronary vascular model is associated with a second set of fluid dynamics equations comprising one or more parameters including at least one flow resistance parameter, and wherein the lumped-parameter coronary vascular model has less than three spatial dimensions;
generating, using at least one computer system, a modified model representing the first and second portions of the cardiovascular structure by coupling the three-spatial-dimension model of the first portion of the cardiovascular structure with the lumped-parameter coronary vascular model of the second portion of the cardiovascular structure, wherein the first set and second set of fluid dynamics equations associated with the three-spatial-dimension model and the lumped-parameter model are mathematically coupled;
calculating, using at least one computer system, one or more blood flow characteristics including blood flow rate, coronary blood pressure, and/or vessel wall displacement in the first portion of the cardiovascular structure using the modified model by simultaneously solving the mathematically coupled first set and second set of fluid dynamics equations associated with the modified model; and
displaying, using at least one computer system, a visual representation based on the blood flow rate, coronary blood pressure, and/or vessel wall displacement.
2. The method of claim 1 , further comprising:
modifying, using at least one computer system, the second set of fluid dynamics equations associated with the modified model based on a change in a physiological state of the patient, wherein the physiological state comprises a state of rest, a state of exercise, or a state of pharmacology-induced stress; and
recalculating, using at least one computer system, one or more blood flow characteristics including blood flow rate, coronary blood pressure, and/or vessel wall displacement in the first portion of the cardiovascular structure using the modified model by simultaneously solving the mathematically coupled first set and second set of fluid dynamics equations associated with the modified model.
3. The method of claim 1 , further comprising:
modifying, using at least one computer system, a parameter of the second set of fluid dynamics equations associated with the modified model; and
recalculating, using at least one computer system, one or more blood flow characteristics including blood flow rate, coronary blood pressure, and/or vessel wall displacement in the first portion of the cardiovascular structure using the modified model by simultaneously solving the mathematically coupled first set and second set of fluid dynamics equations associated with the modified model.
4. A non-transitory computer readable medium for use on at least one computer system containing computer-executable programming instructions for performing a method for calculating cardiovascular information for a patient, the method comprising:
receiving, using at least one computer system, patient-specific image data representing a first portion of a cardiovascular structure generated using non-invasive imaging techniques, wherein the first portion includes at least one coronary artery emanating from the patient's aorta;
receiving, using at least one computer system, patient-specific image data representing a second portion of the cardiovascular structure generated using non-invasive imaging techniques, wherein the second portion includes at least one coronary artery located downstream from the first portion;
creating, using at least one computer system, a three-spatial-dimension model of the first portion of the cardiovascular structure using the patient-specific image data, wherein the three-spatial-dimension model is associated with a first set of fluid dynamics equations representing the flow of fluid through the cardiovascular structure and comprising one or more parameters for blood flow rate, coronary blood pressure, and/or vessel wall displacement;
receiving, using at least one computer system, vessel morphology data generated using non-invasive imaging techniques;
receiving, using at least one computer system, at least one non-patient-specific resistance parameter value;
creating, using at least one computer system, a lumped-parameter coronary vascular model of the second portion of the cardiovascular structure using the vessel morphology data and the at least one non-patient-specific resistance parameter value, wherein the lumped-parameter coronary vascular model is associated with a second set of fluid dynamics equations comprising one or more parameters including at least one flow resistance parameter, and wherein the lumped-parameter coronary vascular model has less than three spatial dimensions;
generating, using at least one computer system, a modified model representing the first and second portions of the cardiovascular structure by coupling the three-spatial-dimension model of the first portion of the cardiovascular structure with the lumped-parameter coronary vascular model of the second portion of the cardiovascular structure, wherein the first set and second set of fluid dynamics equations associated with the three-spatial-dimension model and the lumped-parameter model are mathematically coupled;
calculating, using at least one computer system, one or more blood flow characteristics including blood flow rate, coronary blood pressure, and/or vessel wall displacement in the first portion of the cardiovascular structure using the modified model by simultaneously solving the mathematically coupled first set and second set of fluid dynamics equations associated with the modified model; and
displaying, using at least one computer system, a visual representation based on the blood flow rate, coronary blood pressure, and/or the vessel wall displacement.
5. The non-transitory computer readable medium of claim 4 , wherein the at least one flow resistance parameter comprises at least one of a coronary arterial resistance parameter, a coronary arterial microcirculation resistance parameter, a coronary venous microcirculation resistance parameter, and a coronary venous resistance parameter.
6. The non-transitory computer readable medium of claim 4 , wherein the lumped-parameter coronary vascular model includes at least one of a coronary arterial compliance parameter or a myocardial compliance parameter.
7. The non-transitory computer readable medium of claim 4 , wherein the coronary blood pressure varies over time.
8. The non-transitory computer readable medium of claim 4 , wherein the lumped-parameter coronary vascular model includes at least one of an atrial elastance parameter or a ventricular elastance parameter.
9. The non-transitory computer readable medium of claim 8 , wherein at least one of the atrial elastance parameter or the ventricular elastance parameter varies over time.
10. The non-transitory computer readable medium of claim 4 , wherein the lumped-parameter coronary vascular model includes an inductance parameter.
11. The method of claim 1 , wherein:
the three-spatial-dimension model comprises a finite element model;
the three-spatial-dimension model comprises a plurality of coronary outlets that feed into the lumped-parameter coronary vascular model; and
the lumped-parameter coronary vascular model comprises resistance parameters implicitly coupled to one or more of the plurality of coronary outlets of the three-spatial-dimension model based on one or more equations of continuity of mass or momentum.
12. The non-transitory computer readable medium of claim 4 , wherein:
the three-spatial-dimension model comprises a finite element model;
the three-spatial-dimension model comprises a plurality of coronary outlets that feed into the lumped-parameter coronary vascular model; and
the lumped-parameter coronary vascular model comprises resistance parameters implicitly coupled to one or more of the plurality of coronary outlets of the three-spatial-dimension model based on one or more equations of continuity of mass or momentum.