This series of two ECGs was obtained from a 41-year-old woman who was brought to the Emergency Department and subsequently suffered cardiac arrest. ECG no. 1 is pre-arrest and ECG no. 2 is post-arrest.  We do not know the symptoms she presented to the ED with, or the type of arrest (bradycardic or VFib, for example).  So, our discussion is speculative.  But the difference between the pre- and post-arrest ECGs is striking.

Do you see any abnormalities in the first ECG which might indicate that an arrest is pending? Is there any clue to her medical problems?  In ECG no. 2, do we see signs of the cause of the arrest, or are all the changes due to the loss of perfusion during resuscitation attempts? 

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