[Partial anomalous pulmonary venous return].

A 51-year-old man with no cardiovascular symptoms was referred for cardiac magnetic resonance imaging (CMRI) for further investigation of alterations observed on previous exams. CMRI revealed biventricular dilatation and paradoxical septal motion compatible with volume overload. Balanced steady-state free precession sequences in axial planes showed an anomalous vein oriented vertically and lateral to the aortic arch, communicating with the innominate vein (Figure 1), and a normal-sized coronary sinus. Three-dimensional angiographic reconstruction of the heart and great vessels showed an anomalous pulmonary vein draining into the innominate vein (Figures 2 and 3), causing partial anomalous pulmonary venous return (PAPVR) from the left upper pulmonary lobe (Qp:Qs of 1.4:1). PAPVR is a venous anomaly in which some pulmonary veins drain into the right atrium, directly or indirectly through a systemic vein. It has an overall incidence of 0.5% and most frequently involves the right lung. Anomalous left pulmonary veins generally drain the upper lobe into the innominate vein. PAPVR causes a left-to-right shunt that is usually insignificant and asymptomatic.