A 75-year-old lady presented with palpitations. Her medical history revealed cardiac surgery with a mitral valve repair combined with a MAZE procedure two years prior to presentation. In the past two years, she has had no complications. The current palpitations were associated with dizziness and a general uncomfortable feeling. Upon physical examination blood pressure was found normal and the pulse was regular at 190 beats/min. Because of the high rate, the heart sounds could not be interpreted.
The ECG at presentation is shown in the attached image. Vagal maneuvers were not effective, nor was adenosine up to a dose of 18 mg. What is the diagnosis? *This patient case is from the Docplexus Editorial Team for educative purposes only.
