Prehospital Ventricular Fibrillation in a Young Woman. What is the Diagnosis?
Posted Sep 15 2012 9:44am
An under 30 yo woman collapsed and was found in ventricular fibrillation, and was successfully defibrillated.
Here is her prehospital ECG
What is it?
ECG diagnosis: There is sinus rhythm. There is what I call a "wavy" pattern and large U-waves (see arrow). Do not mistake the U-wave for a T-wave, or the long Q-U interval for a long QT. This is diagnostic of hypokalemia. The K was 1.3 mEq/L.The patient eventually recovered.
Here are more ECGs of hypokalemia which demonstrate the "wavy" pattern:
Notice the "wavy" pattern in V2 and V3, created by downsloping ST depression followed by the U-wave.
When there is an apparent T-wave with an apparent "down-up" pattern (in contrast to an up-down pattern, as in Wellens'), the terminal "up" portion is almost always NOT a T-wave, but rather a U-wave. There is one exception to this: when the down-up is actually reciprocal to an up-down: this happens with Wellenesque T-waves in opposite leads aVL and III: Wellenesque up-down T-wave in lead III, indicative of inferior Wellens' waves (and thus inferior Non-STEMI), will have a reciprocal down-up in lead aVL and vice versa.
Here is another
K = 1.4. Notice again the wavy pattern in almost all leads, with down-up. The end of each wave is the (upright) U-wave.