  Image-based computational fluid dynamics (CFD) has emerged as a powerful tool
to study cardiovascular flows while 2D echocardiography (echo) is the most
widely used non-invasive imaging modality for diagnosis of heart disease. Here,
echo is combined with CFD, i.e., an echo-CFD framework, to study ventricular
flows. To achieve this, our previous 3D reconstruction from multiple 2D-echo at
standard cross-sections is extended by 1) reconstructing valves (aortic and
mitral valves) from 2D-echo images and the superior wall; 2) optimizing the
location and orientation of the surfaces to incorporate the physiological
assumption of fixed apex as a reference (fixed) point for reconstruction; and
3) incorporating several smoothing algorithms to remove the nonphysical
oscillations (ringing) near the basal section observed in our previous study.
The main parameters of the reconstructed left ventricle (LV) are all within the
physiologic range. Our results show that the mitral valve can significantly
change the flow pattern inside the LV during the diastole phase in terms of
ring vortex formation/propagation as well as the flow circulation. In addition,
the abnormal shape of unhealthy LV can drastically change the flow field during
the diastole phase. Furthermore, the hemodynamic energy loss, as an indicator
of the LV pumping performance, for different test cases is calculated which
shows a larger energy loss for unhealthy LV compared to the healthy one.
