The X-mark signature of pulmonary veins in an infant’s heart

We present here the case of an infant with interesting pulmonary venous anatomy in which pulmonary veins drain into systemic veins via 2 separate obstructed vertical veins (VVs). The 2-month-old female patient presented with severe cyanosis and respiratory distress. An echocardiographic study revealed right atrial isomerism, complete atrioventricular septal defect, double outlet right ventricle, pulmonary stenosis, a single left-sided superior caval vein (SVC), and supracardiac obstructed total anomalous pulmonary venous connection (TAPVC). Pulmonary veins on both sides drained into the right innominate vein (RIV) and leftsided SVC via 2 separate rightand left-sided VVs obstructed at their entrance to RIV and left-sided SVC, respectively (Fig. 1a-d). She was taken to the catheterization laboratory under emergency conditions for stent implantation to the stenotic VVs to relieve the obstruction (Fig. 1e, f and Video 1). A 6×12-mm Omnilink RADIX 2 stent was placed to the right-sided VV of the patient, and the gradient of the obstruction decreased from 27 mm Hg to 9 mm Hg and the oxygen saturation improved from 55% to 80%. There is a considerable variability reported about the pulmonary to systemic venous connection in all forms of TAPVC, especially in heterotaxy syndromes. However, to our knowledge, the left and right lower veins draining into a confluence from which the left and right vertical veins arise and take the left and right upper veins, respectively, is a rare entity. Being aware of this entity for accurate diagnosis by echocardiography and emergent transcathether or surgical manipulations to relieve the obstruction is crucial for the outcome.