Table 5. Frequent causes of electrocardiographic electrode placement and artifacts: REVERSE mnemonic.

^aAlso, negative P-QRS-T in lead I. And concordant negative QRS and T waves in lead I, II, III, aVL, and/or aVF (right arm and left leg, right arm and left arm, and right leg and left leg misplacement).

^bAlso negative R wave in lead I, positive R wave in aVF.

^cAn isolated “flat” lead.

^dThe P wave in lead I is greater than in lead II. The sensitivity of this finding is 90 percent.

^ePredominant R wave in V₁ and predominant S wave in V₆. Also, the orientation of the QRS complexes in leads I and V₆ should be the same.

^fNegative P waves in lead I.

^gThese artifacts mimic tachycardias or ST-T changes.

M: mnemonic; mV: millivolt; <: less than

M	Abnormal electrocardiogram finding	Reversal of electrode leads
R	R wave is positive in aVR (P wave also is positive).a	Left arm and right arm
E	Extreme axis deviation: QRS axis between +180 degrees and -90 degreesb	Left arm and right arm
V	Very low voltage (<0.1 mV) amplitude in an isolated limb leadc	Right leg and left arm or right arm
E	Exchange amplitude of the P wavesd	Left arm and left leg
R	R wave: abnormal progression in the precordial leadse	Precordial leads (V1 through V6)
S	Suspect dextrocardiaf	Left arm and right arm
E	Eliminate noise and interferenceg	Artifact