<prompt> All are ECG changes in hypokalemia, except:U waveU waveST segment saggingT-wave flattening or inversionQT interval prolongation  <response>: Answer is D QT Interval prolongation Hvpokalemia may also present with a apparently prolonged QT interval on ECG. However this apparently prolonged QT interval is in reality the QU interval that mimics a prolonged QT interval due to fusion of T-U waves. Prolonged QT interval is the single best answer of exclusion. QT interval and 11 pokalemia Hypokalemia causes an apparent prolongation of the QT interval but the real QT interval remains normal The apparent prolongation of QT interval is due to fusion of the T and U waves T-U fusion 