History: A 39-year-old woman presents to the emergency department complaining of palpitations. She says she has also had "a little diarrhea" today, but that she has similar symptoms any time she is stressed. She denies any fever, abdominal pain, chest pain, syncope, or near-syncope. She also denies any relevant medical history but says she does take furosemide as needed when her legs swell. She states that her regular doctor ordered a full blood panel and an echocardiogram to look for a cause of the swelling and that everything was fine.
Examination: Her exam is essentially normal including her vital signs. There are no rales and no peripheral edema. She does, however, seem a bit shaky/tremulous.
Initial concerns: Dysrhythmia, electrolyte abnormality
Testing: Her ECG is shown in Figure 1, at top right (click on image to enlarge).
- What are the ECG findings?
- What is the most likely diagnosis?
- What is the most likely cause?
For answers and discussion, please click below.