The content of the echocardiogram videos can be summarized in two different forms. This is a story-board type of summary in which every view of the echocardiogram video is represented by a single frame of that particular view. The important issue here is what is the best representative frame for each view.
Heart has two extreme states at each cardiac cycle.
At one extreme heart is most expanded and the blood is flowing through the valves to the ventricles to fill them up. At the other extreme heart is most contracted since the ventricles are pumping the blood out through the main veins. Hence one cardiac cycle can be represented by these two extreme states to give a fair idea of the heart condition. But the dynamics of the cardiac structure are very comlex between these two extreme states, therefore representing a cycle of the heart motion with these two states only does not help the specialist for diagnosis purposes. This frame will serve as a visual cue to browse the content of the echo video and is not aimed for diagnosis purposes.