by the Institutional Animal Care and Use Committee at the Mayo Clinic).

Previous LV reconstruction method {#Previous LV reconstruction method}
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The following steps are performed by Rajan et al. [@rajan2016automated] to reconstruct the LV from 2D-echo images:

1.  **Endocardial border detection**\
    LV endocardial borders are identified using the gradient in the RGB (Red, Green, Blue) values and extracted from black and white echo image in standard long axis (LA) and short axis (SA) echo projections of a pig heart for an entire cardiac cycle with the frame rate ranged from $36$ fps to $55$ fps for different sections.

2.  **B-spline data smoothing**\
    The segmented boundaries extracted from echo images are not smooth and a B-spline curve fitting is used for smoothing the detected endocardial borders.

3.  **Temporal interpolation**\
    Since the image frame rate for various sections is not the same, temporal interpolation is used to obtain different cross-sections at the same time instants. A cubic spline with natural boundary conditions is used for temporal interpolation [@rajan2016automated].

4.  **Scaling, positioning and orientation of the LV sections**\
    The left ventricular end-diastolic dimension (LVEDD) is chosen as the scaling parameter to scale all the extracted data to the physical dimension. The angular 