Fig. 4

Schemes showing the strategy of making a differential diagnosis of dilated coronary sinus. This is an original illustration. Tracing the inflow vein of the CS in parasagittal views assists in clarifying the reasons for its dilatation. If the inflow vein extends cephalically, it turns to be the left innominate vein in the case of a LSVC (a). If the inflow vein turns to the rear of the atrium when the sound beam is rotated from the sagittal view to the transverse view, the vessel might be the CPV in the case of an anomalous pulmonary venous connection (b). If a vessel runs cephalically, running parallel to the inferior vena cava and ultimately joining the coronary sinus, it may be the aberrant ductus venosus (c). CPV: common pulmonary vein; CS: coronary sinus; DV: ductus venosus; HV: hepatic vein; LA: left atrium; LSVC: left superior vena cava; PA: pulmonary artery; RA: right atrium