An 89-year-old man was referred to our institution because of mild chest discomfort. He had no respiratory symptoms. He had undergone pacemaker (VVI type) implantation because of tachybradycardia syndrome 15 years previously. A 12-lead ECG showed a sinus rhythm with a rate of 56 beats per minute and non-specific intraventricular block. Physical examination revealed a blood pressure of 120/80 mmHg. There was no history of trauma, diabetes or surgery. The patient also had no connective tissue disorders or any other systemic anomalies and there was no significant family history of disease. Chest X-ray showed a cardiothoracic ratio of 0.64 and no active lung lesion.
Cardiac ECG-gated 64-slice multidetector-row computed tomography (MDCT) showed no significant coronary artery stenosis (not shown here). However, MDCT images showed a double orifice within the mitral valve ( Figs. 1A, 1B and 2 ; Video 1 ). A central bridge of fibrous or abnormal leaflet tissue connecting the two leaflets of the mitral valve and dividing the orifice into two unequal orifices (medial and lateral) was seen. No other congenital cardiac anomalies were identified by MDCT. Transthoracic echocardiography confirmed these findings and revealed mild mitral regurgitation ( Figs. 1C and 1D ; Videos 2, 3 ). Medical treatment alone controlled his symptoms and the patient was discharged.
