Serum potassium (mEq per L)*Electrocardiograph waveformSerum potassium (mEq per L)*Electrocardiograph waveformSerum potassium (mEq per L)*Electrocardiograph waveform
> 9.0
Sinusoidal wave pattern		> 5.5
Peaked T wave		< 3.5 to ≥ 2.0
ST segment depression, T-wave inversion, prominent U wave
> 5.5 to ≤ 9.0
Wide QRS duration**		3.5 to 5.0
Normal sinus rhythm		< 3.5 to ≥ 2.0
T- and U-wave fusion
> 5.5 to ≤ 9.0
Bradyarrhythmias**		< 3.5 to ≥ 2.0
Decreased amplitude of T wave		< 3.5 to ≥ 2.0
Prolonged QT
> 5.5 to ≤ 9.0
Loss of P wave; junctional rhythms**		< 3.5 to ≥ 2.0
U waves, best seen in leads V2 and V3		< 2.0
Ventricular tachycardia, torsades de points
> 5.5 to ≤ 9.0
Prolonged PR interval