Cor triatriatum is among the rarest of all congenital cardiac abnormalities accounting for 0.1-0.4% of all congenital heart disease. Its coexistence with a very prominent Eustachian valve which mimics a Cor triatriatum dextrum is an exceptionally rare finding in an asymptomatic adult. We report the case of a 44 year old male who presented to our department on observing a pulse rate of 44 beats per minute during a home blood pressure check with his digital sphygmomanometer. Clinical examinationwas however, unremarkable and resting electrocardiography showed sinus rhythm with atrial premature complexes. The diagnosis was made on a two dimensional transthoracic echocardiography. Isolated atrial premature complexes and bradycardia may be a clinical presentation of Cor triatriatum in adult population. Although extremely rare, its coexistence with a prominent Eustachian valve may remain asymptomatic into adult life.
Key words: Cor triatriatum sinistrum, prominent Eustachian valve.