For the initial ECG (above) the precordial electrodes were misplaced over the right side of the chest whilst maintaining the correct placement of the limb electrodes. This has resulted in poor R-wave progression in the precordial leads with decreasing QRS amplitudes and T-wave inversion. The limb leads remain normal/unchanged.
Repeat ECG (with corrected electrode placement):
This is similar to the characteristic pattern seen in dextrocardia:
- Right axis deviation
- Inversion of aVR (global positivity)
- Inversion of lead I (global negativity)
- Absent R-wave progression in the precordial leads with dominant S waves throughout
Of note, reversal of the left and right upper limb electrodes may produce a similar picture to dextrocardia in the limb leads, but with normal appearances in the precordial leads. See LITFL for an excellent review on on the topic of limb lead reversals.