Operating instructions

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HeartView CT
ECG Trace Editor
The ECG trace editor is used to modify the ECG signal.
This editing tool is available after spiral scan data has
been acquired. By using the right mouse menu on the
Trigger tabcard you have access to several modifica-
tion tools for the ECG Sync, such as Delete, Disable,
Insert. In patients with only single or few extra-systolic
beats overall image quality may be improved by edit-
ing the ECG prior to reconstruction. Deleting the corre-
sponding R-peaks prevents image reconstruction in
the extra-systolic heart periods. Please keep in mind
that absolute gating (in ms) must be chosen if R-peaks
are deleted. Although ECG-gated spiral scanning is less
sensitive to variable heart rates than ECG-triggered
sequential scanning, the examination of patients with
complex arrhythmia that results in unpredictable vari-
ations of the RR-intervals (e.g. complex ventricular
arrhythmia or multiple extra beats) can result in lim-
ited image quality and should be performed in excep-
tional cases only.