Hypokalaemia causes typical ECG changes of widespread ST depression, T wave inversion, and prominent U waves, predisposing to malignant ventricular arrhythmias
The U wave is a small (0.5 mm) deflection immediately following the T wave, usually in the same direction as the T wave. Best seen leads V2 and V3.
A 50 year old Chinese female presents with severe weakness. She has a history of previous similar episodes that self-resolved. What's going on?