Three-dimensional quantitative heart hemodynamics in medical imaging
A medical system is provided for three-dimensional hemodynamic quantification. Comprehensive three-dimensional (3D) plus time (3D+t) assessment of flow patterns inside the heart are provided by a combination of lumped-parameter modeling and computational flow dynamic modeling. Using medical scanning, the lumped parameter model is personalized to a given patient. The personalized lumped-parameter model provides pressure curves (i.e., pressure as a function of time) for one or more locations. Using geometry of the patients heart segmented from the medical scanning and the pressure curves as boundary conditions, the computational flow dynamics model calculates the absolute pressure for any location (e.g., for a three-dimensional field of locations) in the patient heart at any one or more phases of the cardiac cycle. More accurate absolute pressure may be provided without invasive measurement.
1. A method for three-dimensional hemodynamic quantification in a medical system, the method comprising:
capturing cardiovascular spatial data and flow data of a heart of a patient with a medical scanner of the medical system, the spatial and flow data representing a three-dimensional volume;
measuring pressure data of the patient with a pressure sensor of the medical system;
generating a three-dimensional representation of a portion of the heart from the spatial data;
estimating flow across valves of the heart from the flow data;
personalizing a lumped-parameter hemodynamics model representing at least the portion of the heart of the patient, the personalizing using the spatial data, the flow across the valves, and the pressure data, wherein personalizing the lumped-parameter hemodynamics model comprises calculating mean arterial pressure from the pressure data, calculating ejection fraction and end-diastolic volume from the spatial data, calculating values for a first sub-set of parameters of the lumped-parameter hemodynamics model from the mean arterial pressure, ejection fraction, and end-diastolic volume, and calibrating a second sub-set of the parameters of the lumped-parameter hemodynamics model with an optimization algorithm;
quantifying a hemodynamic parameter from computational flow dynamics using the three-dimensional representation and using the lumped-parameter hemodynamics model for a boundary condition, the quantifying providing a three-dimensional distribution of the hemodynamic parameter for the portion of the heart; and
indicating a metric on a display for the patient, the metric being a function of the quantifying of the hemodynamic parameter.
2. The method of claim 1 wherein capturing the cardiovascular spatial data and the flow data comprises capturing ultrasound data of the heart with the medical scanner comprising an ultrasound scanner.
3. The method of claim 1 wherein measuring the pressure data comprises measuring with a pressure cuff.
4. The method of claim 1 wherein generating the three-dimensional representation comprises segmenting the portion of the heart as represented in the cardiovascular spatial data.
5. The method of claim 1 wherein generating the three-dimensional representation comprises separately segmenting different parts of a left heart of the heart and fusing the different parts together into a mesh for the portion of the heart.
6. The method of claim 1 wherein estimating the flow comprises estimating the flow across regions detected in the spatial data for an atrial valve and a mitral valve, the flow calculated from the flow data for the regions.
7. The method of claim 1 wherein personalizing the lumped-parameter hemodynamics model comprises personalizing pulmonary circulation as a pulmonary resistance and compliance with the flow data, personalizing a time varying elastance model for heart chamber flow with volume over time from the spatial data and velocity from the flow data, personalizing valve resistance and inertance from the flow data, and personalizing systemic circulation with a Windkessel model.
8. The method of claim 1 further comprising determining a pressure-volume loop from the personalized lumped-parameters hemodynamics model, and wherein quantifying comprises constraining an integration constant as a function of the pressure-volume loop.
9. The method of claim 1 further comprising determining pressure over time from the personalized lumped-parameters hemodynamics model, and wherein quantifying comprises quantifying with the pressure over time as the boundary condition.
10. The method of claim 1 wherein quantifying comprises quantifying the hemodynamic parameter as temporally-consistent pressure field during an iso-volumic phase.
11. The method of claim 1 wherein quantifying comprises quantifying with Navier-Stokes equations with finite element modeling.
12. The method of claim 1 wherein quantifying comprises quantifying with aortic pressure over time from the lumped-parameter hemodynamics model as the boundary condition at an aortic vessel of the three-dimensional representation, and with atrial pressure over time from the lumped-parameter hemodynamics model as the boundary condition at a mitral rim.
13. The method of claim 1 wherein quantifying comprises calculating pressures along tissue as the three-dimensional distribution.
14. The method of claim 1 wherein quantifying comprises calculating pressure, velocity, or pressure and velocity fields.
15. The method of claim 1 wherein indicating the metric comprises indicating an apical residence time derived from the hemodynamic parameter.
16. The method of claim 1 wherein personalizing comprises personalizing with the lumped-parameter hemodynamics model representing one or more chambers and one or more valves.
17. The method of claim 16 wherein personalizing comprises personalizing with a change in volume of the one or more chambers being a difference in out and in flow rates and resistance and inertance of the one or more valves being a function of a difference in out and in pressures.
18. The method of claim 16 wherein personalizing comprises personalizing with the lumped-parameter hemodynamics model representing systemic circulation separately from the one or more chambers and the one or more valves.
19. The method of claim 1 wherein quantifying comprises constraining an integration constant in a Poisson solver during isovolumetric stages with a pressure from the lumped-parameter hemodynamics model.