A young woman with vomiting

A 20-something presented with vomiting.An ECG was recorded:HR is 101The prior ECG was normal.The computerized QT measurement was 353 ms, and Hodges QTc was 411 msWhat is going on?There aredown-up T-waves, in which the QT interval (measure wrong by the computer) is too long.I measure it as460 ms in lead V3, with aHodges QTc of 532 ms.There is also some diffuse non-specific ST depression.Down-up T-waves should make you think one of two things:1) reciprocal to up-down T-waves  a) up-down waves in leads V7-V9 of reperfused posterior MI often manifest with down-up T-waves in V2 and V3  b) in lead III, reciprocal to aVL  c) in lead aVL, reciprocal to III2) Hypokalemia, in which the up component is really a U-wave.  In these cases the apparent QT is very long, and is really a QU-wave.DDx of ST depression in the presence of a normal QRS (i.e., not LVH, LBBB, RVH, RBBB, WPW, etc.) is:1) non-pathologic2) ischemia3) digoxin4) hypokalemiaHere are leads III and V3 magnified:Hypokalemia is the etiology here.  K was 2.3 mEq/L.===================================MY Comment by KEN GRAUER, MD (5/3/2020):===================================Interesting case presented by Dr. Smith — especially from the viewpoint of clinical synthesis. The patient is a 20-something woman, who presented with vomiting and the ECG that I have labeled and reproduced in Figure-1.I arrived at the same conclusion as Dr. Smith — although my path for getting the...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs