Methods: Between January 2010 and March 2012, six patients (3 boys, 3 girls; mean age 4.1; range 3 days - 9 years) were diagnosed with an absent right superior vena cava (RSVC) accompanied by persistent left superior vena cava (PLSVC) in our clinic. The diagnosis of the absent RSVC was established by echocardiography and angiography.

Results: Diagnosis of the absent RSVC was confirmed by echocardiography in four patients. The diagnosis was based on cardiac catheterization and angiography in two patients. Additional cardiac anomalies included peripheral pulmonary stenosis, patent ductus arteriosus, tetralogy of Fallot, atrial septal defect, ventricular septal defect and interrupted aortic arch type B. One patient had Trisomy 9p syndrome, while another one was the baby of a diabetic mother. Three patients were followed clinically, while other three patients were operated.

Conclusion: Absent RSVC should be thoroughly investigated in cases with a large coronary sinus along with increased coronary sinus flow and PLSVC, as evidenced by echocardiography.