Mindray BeneView T1, Operator'S Manual

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8.6.9 Adjusting ST Measurement Points
As shown in the figure below, the ST measured for each beat complex is the vertical difference between two
measurement points with the R-wave peak as the baseline for the measurement.
The ISO and ST points need to be adjusted when you start monitoring and if the patient’s heart rate or ECG morphology
changes significantly. Exceptional QRS complexes are not considered for ST-segment analysis.
WARNING

Always make sure that the positions of ST measurement points are appropriate for your patient.
To adjust the ST measurement points:
1. In the [ ST Analysis ] menu, select [ Adjust ST Point >> ]. In the [ Adjust ST Point ] window, three vertical lines
represent the ISO, J and ST point positions respectively.
2. Use the arrows and besides the [ View Leads ] button to select an ECG lead with obvious J point and R
wave.
3. Adjust the position of [ ISO ], [ J ] or [ ST Point ].

The ISO-point (isoelectric) position is given relative to the R-wave peak. Position the ISO-point in the middle of
the flattest part of the baseline (between the P and Q waves).

The J-point position is given relative to the R-wave peak and helps locating the ST-point. Position the J-point at
the end of the QRS complex and the beginning of the ST segment.

The ST-point is positioned a fixed distance from the J-point. Move the J-point to position the ST-point at the
midpoint of the ST segment. Position the ST-point relative to the J-point at either [ J+60/80ms ], [ J+40ms ],
[ J+60ms ] or [ J+80ms ]. When [ J+60/80ms ] is selected, the ST-point will be positioned 80 ms (heart rate 120
bpm or less) or 60 ms (heart rate more than 120 bpm) from the J-point.
R-wave peak
P
T
Isoelectric point
ST measurement point
Difference=ST value
J point
Q