Figure 1.

(A) Maximum intensity projection pulmonary arterial phase CT images of the thorax reveal extensive venous collaterals arising from the superior vena cava (arrow), (B) which join to the inferior vena cava (arrowhead) and markedly dilated IVC and right atrium (star). (C) An apical 4 chamber view on transthoracic echocardiography, demonstrating an echodense muscular band within the RV, consistent with a DCRV. (D) Balanced steady state free precession (B-SSFP) cine true axial reveal a thickened muscular band extending across the right ventricle (large arrow). (E) Subtracted MR pulmonary angiogram via right antecubital vein injection reveals a patent Glenn shunt and tortuous venous collaterals extending from the SVC to IVC as demonstrated on the CT examination. Note there is only very minimal reflux of contrast into the proximal left innominate vein (arrow). (F) Selective venogram of the left innominate vein demonstrates the large venous collateral draining into the left superior pulmonary vein (arrow) along with the previously demonstrated SVC-IVC venous collaterals (arrowhead).