Fig. 1

Transthoracic apical 4-chamber view with color Doppler (a) showing turbulence in the roof of the left atrium near the right pulmonary vein suggesting pulmonary venous obstruction or stenosis. On cardiac magnetic resonance imaging (b), a membrane (arrow) was demonstrated in the left atrium, with the left pulmonary veins draining into the left atrium, and the right pulmonary veins into the accessory (proximal) atrial chamber