Complex sentence: More severe symptoms such as tetany and paralysis have commonly been reported.Cardiac arrhythmia on ECG and sudden cardiac death and long QT have been reported due to low potassium levels.
Split into simpler sentences: More severe symptoms such as tetany and paralysis have commonly been reported. Abnormal heart rhythms and a prolonged QT interval can be detected on electrocardiogram and cases of sudden cardiac death have been reported due to low potassium levels.