At present, nearly half of the patients seen at our institution for a second opinion of a previously rendered diagnosis of LQTS are departing without such a diagnosis ... 16 17 The U wave is a common ...

Hypokalemia causes U waves in the ECG seen as a positive wave just after the T wave. Hyperkalemia causes peaked T waves initially, then an intraventricular conduction delay with a widened QRS ...

How often do you see an ECG that is just a little off? Maybe the T wave is flat, oddly-shaped or inverted. Maybe the ST segment is coved, very minimally-depressed or shows some J point elevation.