Welch Allyn Cardioperfect Workstation, PEDMEANS ECG Interpretation Module - Physicians - User Manual - Manual (Page 23)

CardioPerfect Workstation
PEDMEANS ECG Interpretation Module Physicians Manual
DIR 80015051 Rev. C 23 / 55
2.16 Repolarization
Negative T waves are classified in one of the following categories:
“flat”:
positive T amplitude < 50 µV and negative T amplitude

50 µV
“(abnormal) small negative”: ULN + 50 < negative T amplitude

ULN + 100 µV
“(abnormal) negative”: ULN + 100 < negative T amplitude

ULN + 250 µV
“large negative”: ULN + 250 < negative T amplitude

ULN + 500 µV
“very large negative”: negative T amplitude > ULN + 500 µV
Using this negative T-wave classification, repolarization statements can be made for five different
localizations: “inferior” (II, III, aVF), “highlateral” (I, aVL), “right precordial” (V3R, V1), “mid precordial”
(V2, V4), and “left precordial” (V6, V7). Because normal T waves can be negative in V3R, V1, and V2,
the ULN of the negative T wave is used. In the other leads the ULN is zero. The severity of a
repolarization disturbance is indicated by one of six possible grades: “minimal”, “minor”, “slight”,
“moderate”, “strong”, “very strong”. The grades of severity are determined by considering the
negativity of the T wave in the leads that are pertinent to a particular localization.
In general, the statement “very strong repolarization disturbance”, where denotes one of
the five localizations mentioned above, requires a very large negative T wave in at least one of the
leads pertaining to that localization with additional less severe constraints on the remaining leads. In a
similar way, the statement “strong repolarization disturbance” requires a large negative T wave
in at least one of the relevant leads. Statements for “moderate”, “slight”, and “minimal” repolarization
disturbances require negative, small negative, and flat or low negative T waves, respectively. Grade
“minor” requires both small negative and flat or low negative T waves to be present.
Additionally, the program looks for mainly positive T in the right-precordial leads, for children aged 3
days up to 6 years.
Say: “right precordial repolarization disturbance”
if: positive T amplitude – negative T amplitude > 100 µV in 1 of V3R, V1
and 3 days < age < 6 years
After each repolarization statement, a statement as to the cause of the repolarization disturbance is
appended. Depending on the T abnormalities found and possible other abnormalities, such as LVH,
the program may append one of the following statements:
“secondary to LVH”
“secondary to RVH”
“secondary to RBBB”
“secondary to LBBB”
“secondary to infarct”
“compatible with early repolarization”