HEXAD ST Analysis
When operating with the IntelliVue Information Center iX, the optional
Hexad algorithm generates a Mason-Likar 12-lead ECG from a 6-wire
leadset (including four limb electrodes and two chest electrodes) placed
according to the Mason-Likar 6-electrode placement.
To generate a derived 12-lead ECG using this configuration, 8 out of the 12
leads are directly acquired (I, II, III, aVR, aVL, aVF and the two
directly-recorded V leads) and only 4 precordial leads need to be derived.
This means that 8 of 12 are identical to the 12 leads acquired using a full set
of 10-wire standard ECG lead set. For more information refer to the 12 Lead
ECG Monitoring Using a Reduced Lead Set Application Note, Part Number
ST Alarms are yellow alarms. They are announced after exceeding alarm
limits for one minute. ST Alarm Limits can only be set at the Information
Center. Each ST lead has its own alarm limit. ST alarms are triggered when
an ST value exceeds its limit for more than one minute. Turning ST Alarms
off turns off alarms for all ST leads.
The STE Alarm is a yellow alarm. It is announced after exceeding alarm
limits for one minute. It can be turned on and off at the Information Center,
however its limits are not adjustable. The STE alarm limits are gender
specific and can be set individually for limb leads, V2/V3 leads, and
V1/V4/V5/V6 leads. The default values, for example on V2 and V3 1.5 mm
for females and 2.0 mm for males, are based on the recommendations from
the American Heart Association and American College of Cardiology.
The ST Elevation measurements with automated J-point determination
generate ST Elevation alarms, in addition to the ST measurements at the
user-defined ST point (J+offset), which may be useful for ST depression
alarms. When ST and STE analysis are both in use, this may result in
redundant alarms for ST elevations. Because of the different measurement
points, there may be different values obtained. Thus there could be an ST
alarm and an STE alarm but the STE alarm may announce sooner based
upon the values obtained.
ST/AR ST Analysis Algorithm
ECG and Arrhythmia Monitoring