The left ventricle has an important function in our body. The left ventricle receives oxygenated blood from the left atrium and brings through the aorta to the body. Therefore, estimation and visualization of blood flow velocity in the left ventricle are essential in clinical diagnosis. Color Doppler ultrasound is one of the instruments for left ventricle assessment that is used to detect blood flow velocity in the heart. However, color Doppler ultrasound shows the two-dimensional (2D) distribution of the one-dimensional (1D) velocity component of blood flow, forward or away along the transducer. The purpose of this study is to estimate and visualize the blood flow velocity in the left ventricle of the healthy volunteer and heart failure volunteers (mitral stenosis and mitral regurgitation) by Doppler ultrasound using echodynamography (EDG) method. The purpose of EDG is to estimate velocity component in a perpendicular direction to the ultrasound beam and to visualize the 2D velocity vectors of blood flow in the left ventricle. EDG composed the flow into the vortex (vortices laminar flow) and base flow (non-vortical laminar flows) components. The separation of flow is based on the continuity equation of fluid dynamics and hydrodynamics characteristics (stream function and flow function). The results show the blood flow velocity vectors are higher in the heart failure cases than the healthy case and indicated the vortex existence in the heart failure cases. In conclusion, the EDG method successfully estimated and visualized blood flow velocity in the left ventricle of the healthy and heart failure volunteers. Furthermore, the EDG method may contribute to the practical and clinical diagnosis of left ventricle assessment.