User's Manual

ST/AR ST Segment Algorithm
7-8 ST/AR Arrhythmia & ST Segment Monitoring
measurement and the ST point provides the other measurement point. It is
positioned with reference to the J-point.
Algorithm
Processing
ST analysis analyzes ECG signals to classify the heart beats. Only beats
classified as normal or Supraventricular (atrially paced) are used to calculate ST
elevations and depressions.
The ST/AR ST algorithm processing includes special ST filtering, beat selection
and statistical analysis, calculation of ST segment elevations and depressions,
and lead reconstruction and wave generation.
When ST analysis is being performed on two leads, the averaged derived and
reconstructed ST waves and associated ST segment values are given for up to
six leads, depending on the type of patient cable:
• 3-wire: one lead
• 5-wire: up to two leads if monitoring a chest and a limb lead
• 5-wire: up to six leads if monitoring two limb leads
• 5-wire: up to 12 leads if monitoring using EASI
• 6-wire: up to 8 leads if monitoring two limb leads and two chest leads
Note—No ST analysis is done on a patient if an electrode falls off.
R-WAVE PEAK
AT 0 MSEC
J POINT
ISO ELECTRIC
POINT
DEFAULT =
-80 MSEC
MEASUREMENT
POINT
DEFAULT =
J+60 MSEC
DIFFERENCE =
ST VALUE
P
Q
S
ST
T