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Congenital absence of right superior vena cava: a "stomach" within the heart.

A 17-year-old boy with visceroatrial situs solitus had a perimembranous ventricular septal defect scheduled for surgical closure. Preoperative echocardiography confirmed the presence of a left superior vena cava (SVC) and a substantially dilated coronary sinus. After induction of anesthesia, there was marked difficulty in advancing the guidewire into the internal jugular vein during central venous catheterization. After multiple attempts, the guidewire was advanced sufficiently to thread a central venous catheter. At surgery, the right SVC was noted to be absent; the right brachiocephalic vein drained into the left SVC. We closed the ventricular septal defect. Postoperative fluoroscopy revealed that the central venous catheter, after passing through the right internal jugular vein, had crossed the midline into the left SVC (Fig. 1). A venogram confirmed the absence of the right SVC; the right brachiocephalic vein joined the left SVC, which drained into the right atrium through the dilated coronary sinus (Fig. 2). The orientation of the coronary sinus within the heart gave the appearance of a stomach, with lesser and greater curvatures. Agitated saline solution injected into the left and right brachial vein showed contrast enhancement of the right atrium through the coronary sinus (Fig. 3). 
 
 
 
Fig. 1 Fluoroscopic image shows the central venous catheter passing through the right internal jugular vein and then crossing the midline into the left superior vena cava. 
 
 
 
 
 
Fig. 2 Venograms. A) Contrast injection into the right internal jugular vein shows that the right brachiocephalic vein joins the left brachiocephalic vein and drains into the left superior vena cava. The right superior vena cava is absent. B) Contrast ... 
 
 
 
 
 
Fig. 3 Contrast echocardiogram with use of agitated saline solution through the A) right and B) left brachial vein. The coronary sinus fills before the right atrium fills. Real-time motion images are available at www.texasheart.org/journal.