Left ventricle-coronary sinus fistula and left ventricular pseudoaneurysm are unusual and frightening complications after mitral valve replacement. A 27-year-old female patient underwent mitral valve replacement 5 years previously and trans-thoracic echocardiography showed an outpouching lesion at the atrioventricular groove. It was difficult to differentiate whether the lesion was a left ventricle-coronary sinus fistula or a left ventricular pseudoaneurysm by two-dimensional echocardiography. Cardiac computed tomography confirmed a left ventricular pseudoaneurysm compressing the coronary sinus.
Keywords: Coronary sinus fistula; Mitral valve replacement; Pseudoaneurysm.