A 15-year-old girl presents is brought to the ED complaining of palpitations and near-syncope. She is found to be tachycardic on arrival and the following ECG is obtained:
A 57-year-old woman presents to the ED with palpitations and dyspnea. She has a prior history of having an elevated heart rate but has never been formally diagnosed with any specific tachydysrhythmia. The…