There
is symmetrical T-wave inversion in Leads II, III and aVF in
this ECG. Ordinarily this would suggest ischemia localized
to the inferior wall. However, we've gotten a little tricky
here and would like you to note two important, subtle observations.
First
of all, notice aVR. The P wave is upright, the QRS is positive
and the T wave is upright. This is almost never the case.
In aVR all deflections are usually negative because of the
orientation of the lead directly above the cavity of the heart.
In this tracing aVR just doesn't look right.
Secondly,
lead aVF looks exactly like an aVR pattern: P, QRS, and T
are all negative.
In
this ECG the technician inadvertently reversed leads aVF and
aVR. Lead II is affected since it is the instantaneous difference
between aVF and aVR (II = aVF - aVR) and also Lead III is
likewise affected
(III = aVF -aVL). So now the erroneous negative T wave in
aVF also occurs in Leads II and III and gives a pattern consistent
with ischemia. The negative P waves in II, III, and aVF erroneously
suggest an AV junctional rhythm but this arrhythmia would
be benign and is not uncommon in normal individuals. The factitious
rhythm here would not cause a severe problem.
Click
here for the ECG produced with
careful attention to correct lead placement.
