Incidental echocardiographic fi nding of non-obstructive cor triatriatum in a healthy triathlete

A 43-year-old man, who was an elite triathlete, was referred to our sports medical centre for pre-participation screening and abilitation in the triathlon competition. This athlete has been active in racing triathlon and long distance cycling competitions for the last 10 years. His family history revealed no known congenital or other cardiovascular disease and no known causes of premature sudden cardiac death among close relatives. He had no relevant past medical history and physical examination was unremarkable. Peripheral blood pressure was 110/70 mmHg. Resting 12-lead electrocardiogram showed a sinus bradycardia and incomplete right bundle block. The cycloergometre and treadmill maximal exercise test showed a good performance and absence of any electrocardiographic abnormality, with a peak cycling workload of 330 watt, 15 METS on the treadmill Astrand protocol and a maximal heart rate of 165–170 bpm. Twodimensional trans-thoracic echocardiogram demonstrated a left atrium divided into two compartments by an incomplete membrane appearing in an incomplete thin diaphragm in all echocardiographic windows (Figures 1, 2 and 3). The mitral valve appeared slightly dysplastic with mild regurgitation. Pulmonary artery pressure was estimated to be 25 mmHg. Hence, the filling pressure was not elevated and the athlete was asymptomatic. Suspected diagnosis of nonobstructive cor triatriatum sinister was performed. Subsequently, a two-dimensional echocardiogram