Abstract. A 24-year-old woman with no relevant cardiac historypresented for evaluation of palpitation and chest pain. Electrocardiographyshowed non-specific ST-T wave changes in inferior leads. Transthoracicechocardiography showed a dilated coronary sinus. The thoracic computedtomography (CT) scan with contrast showed the normal right superior vena cavaand the persistent left superior vena cava (PLSVC) draining into the rightatrium through the coronary sinus. Transthoracic echocardiography - includingagitated saline infusion to both antecubital veins - and computed tomographyare important non-invasive diagnostic tools for accurate diagnosis of this rarecongenital venous malformation. This malformation is quite frequently found,especially with the advent of cardiac ultrasound or CT, magnetic resonanceimaging (MRI). Key words: Persistent left superior vena cava, coronary sinus,retrograde cardioplegia, resynchronization therapy, echocardiography, computedtomography