In this report we describe the case of a 42-year-old woman who experienced an episode of near drowning during recreational swimming. A diagnosis of Andersen-Tawil syndrome was made based on the patient's dysmorphic features, characteristic T-U-wave patterns and ventricular arrhythmias. To our knowledge, this is the first report of a swimming-triggered cardiac event in a patient with Andersen-Tawil syndrome.