Case report

A 69-year-old male with a history of atrial fibrillation presented with increasing dyspnoea on exertion. He required a pacemaker due to tachycardia–bradycardia syndrome. During percutaneous pacemaker lead placement at another institution, the lead ended up in the left ventricle, confirmed by chest radiograph (Figure 1S (Supplemental)) and transesophageal echocardiography. The lead was removed and the patient had a CT angiography of the chest, which demonstrated a right upper pulmonary vein–superior caval vein window (Figure 1a–c), moderate right cardiac dilatation, and no significant coronary artery disease. The right upper pulmonary vein drained the anterior and medial aspect of the right upper lobe and connected to the posterior wall of the superior caval vein. The rest of the right upper and middle lobe pulmonary veins drained via a common trunk to the left atrium. A transesophageal echocardiogram showed the window (Figure 2S [Supplemental] A, B, C) and a patent foramen ovale. At catheterisation, the pressures were as follows: right atrium, mean 21 mmHg; right ventricle, 53/23 mmHg; pulmonary artery, 46/24, mean of 34 mmHg; pulmonary capillary wedge, mean of 22 mmHg, descending aorta, 106/69 mmHg, and left ventricle, 112/16 mmHg. Saturations were high superior caval vein 65%, inferior caval vein 77%, right ventricle 89%, pulmonary artery 88%, and aorta 99%. The Qp/Qs was 2.8/1.0. Pulmonary vascular resistance was 2.8 Wood units. The coronary arteries had no significant lesions. The superior caval vein measured 17–18 mm proximally and 30–32 mm distally (Figure 2a–c). A 32 mm x 5 cm Endurant II aortic stent graft extension (Medtronic, Minneapolis, MN) was placed into the distal superior caval vein, and a 4.5 cm covered mounted CP stent (B Braun, Bethlehem, PA) was telescoped into the proximal end of the Endurant graft using a 20 mm balloon (Figure 2d–f). Two small right upper pulmonary veins that drained more cranially into the superior caval vein were sacrificed during stent implantation. Post-procedural transesophageal echocardiography showed unobstructed flow from the right upper pulmonary vein to the left atrium and laminar superior caval vein flow (Figure 2S (Supplemental) D, E, F); the mean pulmonary arterial pressure was 20–22 mmHg.

Figure 1.

CT angiography images: ( a ) Axial view demonstrating the window between the right upper pulmonary vein and the superior caval vein (asterisk). ( b ) Right and anterior view and ( c ) left and posterior view of reconstructed images showing the veno-venous window (arrows). Follow-up images: ( d ) axial view showing the stent separating the superior caval vein from the right upper pulmonary vein. ( e ) Reconstructed image from a right and anterior view and ( f ) from a posterior and left view. PV = right upper pulmonary vein; S = superior caval vein.

Figure 2.

( a ) Angiogram in the superior caval vein—AP view. ( b ) Angiogram in a small right upper lobe pulmonary vein—lateral view. ( c ) Angiogram in a large right upper pulmonary vein—lateral view. After stent implantation: ( d ) AP view angiogram in the superior caval vein. ( e ) Lateral view angiogram in the superior caval vein. ( f ) Right upper pulmonary vein angiogram—AP view. AP = Anteroposterior; PV = right upper pulmonary vein; S = superior caval vein; R = right atrium.

The patient had an exacerbation of back pain a week after the procedure. An echocardiogram showed a small to moderate-sized pericardial effusion. On CT angiography, there was no residual communication between the superior caval vein and right upper pulmonary vein. There was a mild to moderate circumferential pericardial effusion measuring 10–12 mm in diameter, with a density of 30–50 Hounsfield units, suggestive of a haemorrhagic component. The patient was clinically stable, and the haemoglobin level was unchanged. Five months post-stent implantation, an echocardiogram continued to show a moderate pericardial effusion. A CT angiography showed a similar-sized effusion, and the right upper pulmonary vein and superior caval vein remained unobstructed (Figure 1d–f). Six months after stent placement, he underwent an elective pericardial subxiphoid window with the removal of 400 ml of pericardial fluid. Two years later, the patient was clinically stable; an echocardiogram showed normal biventricular size and systolic function and no pericardial effusion.