Three dimensional reconstruction of blood flow within the left ventricle: comparison of normal, dilated cardiomyopathy and reduced ejection fraction

Abstract

We have developed a method for creating a 3D reconstruction of blood flow within the left ventricular (LV) chamber from a set of 2D color flow echocardiographic cine loops. The resulting reconstructions allow a physician to view bloodflow in multiple dimensions, permitting an immediate perception of the dynamic shape, size and direction of the flow structures and patterns in their true nature, without the need for the physician to mentally construct 3D views from a limited number of 2D color flow loops. In addition to their value in qualitative assessment, these 3D reconstructions offer the promise of a more complete quantitative clinical assessment of blood flow based on statistical values derived from these 3D models of flow - as opposed to extrapolated from 2D data, as is done clinically today. The ability to measure LV flow rates and volume is quite important because changes inflow rates and volume may prove critical for analysis of patients with heart failure. These measurements are also keys to understanding the ventricular function. We also have defined an approach for creating a 3D reconstruction of LV blood flow over time - in effect, a 4D model of LV blood flow. We have shown that, in the absence of significant velocity aliasing defects, the models obtained by this technique conform to the conservation of flow. Finally, we note that this study can be used to differentiate between normal dilated cardiomyopathy and reduced ejection fraction, although it offers limited insight into the specific causes of these disorders.