IMAGES in PAEDIATRIC CARDIOLOGY

Cor triatriatum sinister is a rare congenital cardiac malformation characterized by a membrane in the left atrium which separates the left atrium into the proximal and distal chambers.Association of cor triatriatum is extremely rare with situs inversus totalis. Here we report a rare case of cor triatriatum sinister with situs inversus totalis in a 5 month old female infant. MeSH: Cor triatriatum, Situs inversus, Patent ductus arteriosus, Infant Introduction Cor triatriatum is a rare congenital cardiac malformation with an estimated incidence of 0.1% of all congenital heart disease and it usually refers to the left atrium (cor triatriatum sinister). In cor triatriatum sinister (CTS) the left atrium is divided by a fibromuscular membrane into two distinct chambers: a posterior-superior chamber receiving the four pulmonary veins and an anterior-inferior chamber (true left atrium) that connects to the left ventricle by means of the mitral valve. In CTS, the obstructive nature of the membrane leads to creation of a pressure gradient, with an associated rise in pulmonary venous pressures. Total situs inversus (TSI) is characterized by a heart on the right side of the midline while the liver and the gall bladder are on the left side.Here we report an extremely rare case of cor triatriatum sinister which is associated with TSI. Case Report A five month old female child was referred for cardiac murmur evaluation. History of suck rest suck cycle was present. No family history of congenital heart disease was noted. Physical examination revealed a pulse rate of 145 beats/minute, blood pressure of 94/50 mmHg, with baseline oxygen saturation of 99%. On cardiac examination, the second heart sound was normal and there was no evidence of pulmonary hypertension. Auscultation of the right chest revealed a 3/6 systolic murmur at the right parasternal border. Other systems were normal.Laboratory investigation showed a hemoglobin level of 10 g% and a white cell count of 16,000 mm. The chest X-ray demonstrated dextrocardia, cardiomegaly and normal pulmonary vascular markings. A gastric air bubble was noted on the right side, and a liver shadow on the left side was present. The electrocardiogram(ECG) revealed a sinus rhythm with dextrocardia. Abdominal ultrasound demonstrated the stomach and spleen on the right side and the liver on the left. The aorta and the inferior vena cava were inverted. Transthoracic echocardiography (TTE) demonstrated {I,L,I} (I, situs visceroatrialis inversus; L, L-loop of the ventricles; I, normally related inverted great arteries). It also showed a fibromuscular membrane across the left atrium, dividing it into two compartments suggestive of cor triatriatum sinister (fig1. & fig2). The two chambers communicated through two restrictive orifices (gradient:16mmHg) (fig3). A small size patent ductus arteriosus (gradient 20/6mmHg) with left to right shunt was present (fig4.). Other cardiac anomalies like patent foramen