Welch Allyn Means ECG Physicians Manual for CP Series Electrocardiographs - User Manual - Manual (Page 22)

MEANS Physicians Manual
Welch Allyn
22
Lateral infarction
Say: “lateral infarct”
if: Q duration

35 ms and Q/R ratio

1/3 in V5 or V6
or Q duration

40 ms and Q amplitude > 100 µV in V5 or V6
or QS pattern in V5 or V6
or R amplitude < 100 µV in V5 and V6
or R amplitude < 150 µV in V4 and V5
and R amplitude < 150 µV or Q wave in V6
or R amplitude in V5 < R amplitude in V4
and R amplitude in V5 < 150 µV
and R amplitude in V5 > R amplitude in V6 or Q wave in V6
Say:
“probable lateral infarct”
if: 35

Q duration < 40 ms and 1/4

Q/R ratio < 1/3 in V5 or V6
or Q duration < 35 ms and Q/R ratio

1/3 in V5 or V6
and R amplitude in V5 < R amplitude in V4  50 µV
or R amplitude in V6 < 150 µV
and R amplitude in V6 < R amplitude in V5

50 µV
and test RBBB did not pass
and test RVH did not pass
Say:
“possible lateral infarct”
if: 25  Q duration < 35 ms and 1/4  Q/R ratio < 1/3 in V5 or V6