RT Journal Article SR Electronic T1 Sinus venosus syndrome: atrial septal defect or anomalous venous connection? A multiplane transoesophageal approach JF Heart JO Heart FD BMJ Publishing Group Ltd and British Cardiovascular Society SP 634 OP 638 DO 10.1136/heart.88.6.634 VO 88 IS 6 A1 J M Oliver A1 P Gallego A1 A Gonzalez A1 F J Dominguez A1 A Aroca A1 J M Mesa YR 2002 UL http://heart.bmj.com/content/88/6/634.abstract AB Objective: To discuss the anatomical features of sinus venosus atrial defect on the basis of a comprehensive transoesophageal echocardiography (TOE) examination and its relation to surgical data.Methods: 24 patients (13 men, 11 women, mean (SD) age 37 (17) years, range 17–73 years) with a posterior interatrial communication closely related to the entrance of the superior (SVC) or inferior vena cava (IVC) who underwent TOE before surgical repair. Records of these patients were retrospectively reviewed and compared with surgical assessments.Results: In 13 patients, TOE showed a deficiency in the extraseptal wall that normally separates the left atrium and right upper pulmonary vein from the SVC and right atrium. This deficiency unroofed the right upper pulmonary vein, compelling it to drain into the SVC, which overrode the intact atrial septum. In three patients, TOE examination showed a defect in the wall of the IVC, which continued directly into the posterior border of the left atrium. Thus, the intact muscular border of the atrial septum was overridden by the mouth of the IVC, which presented a biatrial connection. In the remaining eight patients, the defect was located in the muscular posterior border of the fossa ovalis. A residuum of atrial septum was visualised in the superior margin of the defect. Neither caval vein overriding nor anomalous pulmonary vein drainage was present.Conclusions: Sinus venosus syndrome should be regarded as an anomalous venous connection with an interatrial communication outside the confines of the atrial septum, in the unfolding wall that normally separates the left atrium from either caval vein. It results in overriding of the caval veins across the intact atrial septum and partial pulmonary vein anomalous drainage. It should be differentiated from posterior atrial septal defect without overriding or anomalous venous connections.