V1-V6 waveforms as a surface and image

All 6 precordial leads (V1-V6) can be plotted together at the same time to see positional variations in the EKG waveform with respect to electrode location. Here is an example in which a single cycle of each waveform is extracted from a set of previously recorded EKG data. All six waveforms are synchronized independently about the R peak of the trace, and then they are combined into a single 6 column dataset which can be manipulated or visualized as a unit. This dataset can be plotted as a set of 1d curves, showing the cross-sectional variation in each waveform, as a 3d shaded surface which can be rotated and zoomed with the mouse, or as a 2d image showing the height of the surface as a variation in image color.

Here is a detail of the 3d surface, which contains 6 x 256 points. Time is along the X axis, and the V leads are arranged from front to back along the Y axis:

Here is a detail of the image plot, showing just the V2, V3, and V4 leads arranged left to right, with time going down the plot:

A subset can be extracted from the combined dataset to show detail about some feature along the time axis. Here is a detail of the RS "complex" for all 6 leads:

The combined dataset can be downsampled in order to improve visibility at low magnifications. Here the previous dataset has been downsampled from 256 to 64 points before being plotted as a surface:

Finally, the scale of the Z axis can be enlarged to show detail of the non-RS part of the waveforms. Points of the surface lying outside of the scale boundary can be clipped so as not to obscure other points. Here is a detail of the previous surface showing the positional change in shape of the T "wave". The surface has been rotated by about 90 degrees to show the back of the plot:


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