An unusual example of isolated double-orifice tricuspid valve
A 12-year-old girl presented with palpitation of recent onset. She was previously identified to have a restrictive perimembranous ventricular septal defect (VSD) (restricted by the septal tricuspid leaflet) during infancy. She remained asymptomatic throughout childhood and presented 12 years later with a history of palpitation of one-month duration. On examination, there was left parasternal heave with epigastric pulsations, a wide variably split second heart sound and a pansystolic murmur at the left lower sternal border. There was no cyanosis. The electrocardiogram showed ectopic atrial rhythm with low atrial focus and incomplete right bundle branch block. Transthoracic echocardiography showed dilated right atrium (RA) and right ventricle (RV). An accessory opening of the tricuspid valve (TV) into the left ventricle (LV) was found to be situated in the posterior plane with a separate tensor apparatus [Figure and ]. The atrioventricular junction was overriding the ventricular septum. A large LV-to-RA shunt was noticed through the regurgitant accessory tricuspid orifice during systole. There was unobstructed flow from RA to LV during diastole. The other orifice (RA to RV) was unobstructed and competent. No VSD was seen.\nSurgical findings showed two tricuspid valves. The additional valve orifice with separate tensor apparatus with ruptured chordae was situated posterior and inferior to the normal valve orifice [Figure and ]. On testing with saline, an LV-to-RA shunt was found. Under cardiopulmonary bypass through RA, the abnormal TV leaflets were sutured together and the additional orifice was further closed with a tanned pericardial patch, sutured along the annulus, safeguarding the conduction tissue. There was no residual shunt on postoperative echocardiography.