S12 Vet Monitor User’s Manual
8-25
T wave is too flat or t wave boundary is unclear.
The existence of U wave makes the end of T wave difficult to define.
QTc measurement is unstable.
In the presence of noise, asystole, ventricular fibrillation, and ECG lead off.
In the above situation, you need to select leads with good T wave amplitude, no
visible flutter, and no dominant U wave or P wave. In some cases, such as left and right
bundle branch block or cardiac hypertrophy, QRS complex may widen. If a long QTc is
observed, this should be confirmed to ensure that it is not caused by QRS broadening.
QT measurement cannot be performed in the presence of bigeminy rhythm because
normal cardiac beats are not included in the analysis when they are followed by
ventricular beats.
QT measurement cannot be performed when the heart rate is extremely high (over
180bpm). When the heart rate changes, it can take several minutes for the QT interval to
stabilize. In order to obtain reliable QTc calculation results, it is important to avoid areas
where the heart rate changes.
8.8.2.
Enabling the QT/QTc Monitoring
QT/QTc monitoring function is off by default, and you need to turn it on before
performing QT/QTc monitoring. Enable QT/QTc monitoring as follows:
1.
Select ECG parameter area or waveform area to enter
【
ECG
】
menu.
2.
Select
【
QT
】
submenu→
【
Setting
】
submenu.
3.
Switch on
【
QT Analysis
】
.
8.8.3.
Displaying QT/QTc Parameter
The method for displaying QT parameters and waveforms is as follows:
1.
Enter the
【
Screen Layout
】
page in one of the following ways:
Select
【
Screen Setup
】
quick key→select
【
Screen Layout
】
submenu.
Select
【
Main Menu
】
quick key→from
【
Display
】
column to select
【
Screen Layout
】
.
2.
Click on the location in the parameter area where QT parameters need to be
displayed and select
【
ECG
】
→
【
QT
】
.
