Actiheart User Manual 5.1.31 (Jun 2022)
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5.2 Waveform
Viewer
This window graphically shows all of the raw waveform data captured by the
device, in addition to summary data such as heart rate and movement. Initially
we describe the contents of the “Waveform Viewer” tab which is used to explore
the data.
The view can be navigated either using the “Step Through” buttons and “View
Size” options, or by using the mouse and scroll wheel. To zoom in and out of the
data you can move the mouse across a point of interest and then roll the scroll
wheel to zoom in our out. Once zoomed in, you can use the right mouse button
and drag the time to left or right as an alternative to the << and >> buttons.
The data channels shown in the plot are calculated as follows:
•
ECG:
The full recorded ECG waveform is graphed. When zoomed out,
this will mostly show the outer envelope of the signal which gives a quick
indication of periods of good or bad ECG electrode pickup. When zoomed
in, the individual heart beats are marked in light blue together with a
horizontal line linking them where an IBI interval is judged definitely
correct by the software.
•
ECG Peaks:
This is shown for an Actiheart 5 IBI Mode recording. It is
shown as a flat line with vertical peaks drawn at the timings and
magnitudes of ECG signal peaks recorded by the Actiheart 5. Note that it
includes not just the QRS complexes identified by light blue lines as heart
beats, but also a number of smaller noise peaks in order to allow more
robust analysis and detection of the IBI and heart rate.
