This 41-year old woman reports palpitations since she was a teenager, with the sensation of rapid pounding in her left anterior chest, starting and ending suddenly. Recently, the episodes have been lasting 15-30 minutes and have been associated with weakness and mild dyspnea:

• Sinus rhythm
• Wolff-Parkinson-White

The patient was referred to the arrhythmia service, where EP studies demonstrated an anteroseptal bypass tract, that was successfully ablated. There was no recurrence of palpitations.