Infradiaphragmatic partial anomalous pulmonary venous connection in adulthood. Considerations for management: a single centre experience.

Background and Objectives: Infradiaphragmatic partial anomalous pulmonary venous connection is occasionally diagnosed in adulthood. Management of infradiaphragmatic PAPVC depends on anatomy and clinical presentation.
Methods: Over a 10-year period, we observed seven adult patients (median age 29 years) with partial anomalous pulmonary venous connection. We classified our patients in two groups. Group I: isolated partial anomalous pulmonary venous connection from one pulmonary lobe to the inferior vena cava, three patients. Group II: partial anomalous pulmonary venous connection of the entire right lung to IVC, four patients.
Results: The mean term follow-up was 5.4 years. Patients in Group I have been managed conservatively, as they were asymptomatic, without a significant shunt. Patients in Group II were surgically corrected using long right intra-atrial baffles. After 6 months of follow-up, the first two cases were diagnosed with complete tunnel thrombosis and loss of right lung function. Oral anticoagulation failed to recanalize the tunnel. Considering this serious complication, the other two patients were empirically and preventively treated with anticoagulation after surgery, with good outcome on long-term follow-up.
Conclusions: Conservative management should be considered for asymptomatic patients, without a significant shunt. Surgical treatment of infradiaphragmatic partial anomalous pulmonary venous connection of the entire right lung in inferior vena cava is challenging. Slow blood flow inside the long intra-atrial baffles inclines to thrombosis and occlusion, as we observed in two cases. Therefore, oral anticoagulation should be considered for long baffles with slow blood flow.