Actiheart Guide to Getting Started 5.1.11 (Feb 2020)
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Any areas of the recording that have failed the test are displayed in red on the
scan as shown in the screen below. You may click on the scroll bar just above
the red / green bar to move the main data display to that point. This will allow you
to examine each 10 second region which may have been problematic.
It should normally be obvious from the recording why an area of the recording
has failed, for example due to movement artefacts. If it is not obvious, ensure
that the “Activity” box is selected to show the activity trace recorded with the R
wave. This may help the user identify if the problems have been caused by
movement. If a recording has failed for the 10 second period currently displayed,
as indicated by the graphics to the right of the window, this usually means that
either the noise level is too high or the R wave is too low. The following tests are
applied to determine this:
▪
16-[signal/noise x 2] <7
▪
signal /noise > 4.75
▪
signal > 9.6 but this is normally true anyway
.
In either case, it is necessary to check the position and impedance of the ECG
pads. For further details on the selection of ECG pads and skin preparation,
please see
Section 5
of the Guide to Getting Started.
Note that you will always expect that the beginning and end of the signal test will
be marked as red since these regions will not show a stable ECG pad
connection. This is not a concern
– only those periods of recording where you
know a good signal should have been present.
Scan results
