 An echocardiogram demonstrated significant cyanotic congenital heart disease consisting of normal situs, a left superior vena cava draining into the left atrium, a criss-cross heart with atrioventricular discordance of the right atrium draining through the mitral valve into the left-sided morphologic left ventricle. 
An echocardiogram demonstrated significant cyanotic congenital heart disease consisting of normal situs , a left superior vena cava draining into the left atrium , a criss - cross heart with atrioventricular discordance of the right atrium draining through the mitral valve into the left - sided morphologic left ventricle .