Atrial septal defect combined with partial anomalous pulmonary venous return: complete anatomic and functional characterization by cardiac magnetic resonance.

The presented case regards a 17-year-old male with new-onset right bundle branch block and significantly enlarged right-heart sections as the only pathologic finding on transthoracic echocardiography. Cardiac magnetic resonance (CMR) revealed the presence of a superior sinus venosus atrial septal defect associated with a partial anomalous pulmonary venous return, with the right upper lobe pulmonary vein draining into the superior vena cava. CMR has developed in recent years into an accurate modality for non-invasive evaluation of patients with congenital heart disease, especially through improvements in quality and speed of image acquisition. With echocardiography, sinus venosus defects and anomalous pulmonary vein drainage may be more easily detected by a transoesophageal approach because of the proximity of the transducer to the atrial septum. CMR may be specifically recommended as an alternative to transoesophageal echocardiography in any patient with an unexplained dilatation of the right ventricle.