Click on image to view larger version.

Figure 2 Examples of frame by frame planimetry in three patients with valve area <1 cm² (A), 1 to 2 cm² (B) and more than 2 cm² (C). In each diagragm aortic valve area (AVA) in square centimeters is plotted against time which is expressed in number of video frames (each equal to 33 ms) for one ejection period.