Letâ€™s take another look at the ECG from Part 2.
Does anything stand out?
How about lead V4?
Here you can see the terminal deflection (blue arrow) is positive, and so is the T-wave (inappropriate T-wave concordance). There is also at least 1 mm of ST segment elevation. Thatâ€™s definitely abnormal!
Now letâ€™s look in the inferior leads. They all look abnormal, but Iâ€™m going to use lead aVF as the example.
The terminal deflection is negative (blue arrow) and the T wave is also negative (inappropriately concordant T-wave). The inferior leads are reciprocal to the anterior leads. Could this represent reciprocal changes? Absolutely!
It is sometimes said that reciprocal changes are of no value in the presence of bundle branch blocks. Thatâ€™s not entirely true! You just have to interpret them within the context of appropriate T-wave discordance.
In other words, in the presence of bundle branch block, if the terminal deflection of the QRS complex is negative in lead III and positive in lead aVL, then you will have pseudo reciprocal changes (positive in lead III and negative in lead aVL). This is a normal finding in left bundle branch block, for example.
If, however, the terminal deflection of the QRS complex is negative in lead III (as in this ECG) and the same lead is showing inappropriately concordant ST-segment depression or T-wave inversion, then itâ€™s probably not a pseudo reciprocal change.
Iâ€™d also like to point out that leads V2 and V3 look really strange in this ECGÂ with aÂ merging together of the S-wave and T-wave (sometimes seen in severe hyperkalemia). We would normally expect a terminal R wave in lead V2 with right bundle branch block.
Somethingâ€™s going on here!
Letâ€™s look at some serial ECGs. This one was taken just 4 minutes later.
Hereâ€™s the final ECG in the series, recorded as the ambulance arrived at the hospital.
Quite a difference! Once again, itâ€™s easy to see the value of serial ECGs.
Letâ€™s take a look at lead V2 and see how it changed from the first ECG to the last.
Right bundle branch block: Part 3