A 52 year old female referred by their GP with abnormal biochemistry results.  Below is the patients ECG:

Describe and Interpret the ECG:

Rate: 66 beats per minute

Rhythm:

• Complexes 1-4/6-7/9/11 regular sinus
• Complex 5 PVC
• Complexes 8 and 10 junctional escape complexes with sinus arrest

Axis: Normal

Intervals

• PR 160ms
• QRS 120ms
• QTc/ QU 545ms (Bazett)

Additional:

• Baseline artefact
• ST depression inferolaterally
• T wave inversion inferiorly
• U waves inferiorly

The above ECG shows typical features for hypokalaemia

• U wave
• Prolonged QTc/QU
• ST depression
• Increased automaticity

The patient had a potassium of 2.2mmol/l.  Other electrolytes need to be checked in this case as often patients also have low magnesium +/- low calcium.

ECG obtained from John Larkins ECG of the Week July 2017. With Thanks