A 73-year-old woman with left ventricular systolic dysfunction presents to the emergency department. She is having palpitations and is diagnosed as having atrial fibrillation (heart rate, 130 beats/min). She denies chest pain but is mildly short of breath with a rapid ventricular rate. The patient is not sure how long she has been having palpitations; she thinks they have been intermittent during the past few months but have always resolved after a few minutes.
This episode, however, lasted for more than 2 hours, prompting her to seek treatment. Medical History Well controlled hypertension with hydrochlorothiazide. History of hypothyroidism treated medically with normal findings on sensitive thyroid-stimulating hormone test No history of bleeding problems, strokes, or transient ischemic attacks No syncope or presyncope Known coronary artery disease with 3-vessel coronary artery bypass…
