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Patient
Young man 22 years of age, asymptomatic, with no prior history and a normal cardiac ultrasound (same patient as in Tracing 1);
Trace
There is a reversal of the electrodes of both arms; lead I is inverted (negative P-wave, QRS-complex and T-wave); right axis deviation; normal R wave progression in precordial leads;
Trace
There is a reversal of the left arm/left leg electrodes; lead III is inverted and becomes -III with negative P-wave, QRS-complex and T-wave; leads I and II are switched; P-wave is taller in lead I than in lead II;
Trace
There is a reversal of the right arm/right leg electrodes; pseudo-asystole pattern in lead II; leads aVR and aVF are identical; negative P-wave, QRS-complex and T-wave in lead I;
Trace
There is a reversal of the right arm/right leg electrodes; pseudo-asystole pattern in lead II; leads aVR and aVF are identical; negative P-wave, QRS-complex and T-wave in lead I;
Trace
There is a reversal of the right arm/right leg electrodes; pseudo-asystole pattern in lead III; leads aVL and aVF are identical; similarly, leads I and II become identical;
Trace
There is a bilateral reversal of electrodes of both arms with those of both legs, lead I is nearly isoelectric; leads II, III and aVF become identical; leads aVR and aVL also become identical;
Trace
There is a reversal of the electrodes of both legs; electrocardiographic pattern unchanged;
Exergue
The presence of a negative P-wave and negative QRS in lead I should lead to suspect a reversal of left and right arm electrodes; a flat-line (pseudo-systole) pattern in leads I, II or III should evoke a reversal between the right leg electrode and one of the other 3 limb electrodes.
Normally, lead I represents the difference in potential between the right arm (negative pole) and the left arm (positive pole), lead II represents the difference between the right arm (negative pole) and the left leg (positive pole), lead III the difference between the left arm (negative pole) an