Anomalous pulmonary venous drainage of the right lung into the inferior vena cava

Scimitar syndrome and evolution of managements

The Scimitar syndrome is a rare congenital anomaly that consists in part of total or partial anomalous venous drainage of the right lung to the inferior vena cava (IVC). This descending vein is visible on CXR as a curvilinear density along the right heart border and resembles the curved Turkish sword that gives the condition its name. Scimitar syndrome forms part of the large spectrum of associated conditions known as venolobar syndrome. These include right lung hypoplasia or sequestered segments of the right lung, congenital heart disease and various others. Surgical approaches to the Scimitar syndrome have varied according to the anatomic and pathologic features presented in each case. Here we review the clinical signs and symptoms, diagnostic dilemmas, current medical and surgical managements of Scimitar syndrome.

CORRECTION OF ANOMALOUS VENOUS RETURN FROM THE RIGHT LUNG TO THE INFERIOR VENA CAVA (SCIMITAR DEFORMITY)

Anomalous pulmonary venous drainage to the inferior vena cava is a rare congenital cardiac defect. Oxygenated blood from the right lung enters the right atrium resulting in a left-to-right shunt. Because the radiographic shadow of the anomalous vein resembles a curved saber, this defect has been called the "scimitar" deformity. From 1958 through June 30, 1975, 11 patients underwent surgical correction of this anomaly at our institution with 10 survivors. Diagnosis was made by routine roentgenography of the chest in all but one patient. Eight patients had total correction which consisted of implanting the anomalous vein into the right atrium, opening the interatrial septum and applying a patch graft as a baffle to direct pulmonary venous blood into the left atrium. Five patients had associated cardiac defects which were also repaired. Three patients underwent pneumonectomy and all survived. The only operative death occurred in a 5-year-old female with an atrial septal defect and endocardial cushion defect. We believe the existence of a large left-to-right shunt justifies surgical intervention. The prognosis appears to depend upon the presence of other cardiac or pulmonary anomalies.

Horseshoe lung associated with a variant of the 'scimitar' syndrome

Images

Anomalous pulmonary venous return into inferio vena cava and associated bronchovascular anomalies (the scimitar syndrome)

Among the different anatomical forms of anomalous pulmonary venous return, that of the inferior vena cava is of particular interest for the following reasons: the special radiological pattern which is referred to as the scimitar sign and the associated anomalies which often occur in the lungs. We have successfully operated on three¹ patients who are reported in this paper, and we have included a review of the literature.

Intrapulmonary segment in anomalous pulmonary venous connection. Resemblance to scimitar syndrome

Three cases showing a large anomalous venous channel in the right lung are presented. In each case the large vein was a part of a pulmonary venous collateral system in association with anomalous pulmonary venous connection, partial in one case, and total in two. In two of the cases, each of which was an example of total anomalous pulmonary venous connection, the anomalous vein in the right lung received the entire venous system of the left lung. In the two cases with conventional roentgenograms the anomalous vein within the right lung was apparent. Its shape, in some respects, resembled that of the anomalous pulmonary vein in the scimitar syndrome. Selective pulmonary arteriography appears to offer the best means of differentiation between an anomalous vein of the type described here and that of anomalous drainage of the hypoplastic right lung to the inferior vena cava (the scimitar syndrome).