Our latest emergency department minute quiz from Brady Pregerson, MD, features a woman in her 20s with heart palpitations. Can you determine the correct diagnosis?
History: A woman in her 20s presents to the emergency department for 1 week of intermittent palpitations lasting hours each time. She feels it currently but denies being able to identify anything that triggers or worsens it and is not using any stimulants including coffee. She denies syncope, near-syncope, chest pain, SOB, fever, or other complaints.
Exam: Vital signs are normal. The exam is normal except for a regularly-irregular pulse and heart rate. Specifically, there are no murmurs, rales, or peripheral edema.
An EKG is performed:
What is the most likely diagnosis?