Congenital Portosystemic Venous Connections and Other Abdominal Venous Abnormalities in Patients with Polysplenia and Functionally Univentricular Heart Disease: A Case Series and Literature Review

Objective. Published case reports suggest that congenital portosystemic venous connections (PSVC) and other abdominal venous anomalies may be relatively frequent and potentially important in patients with polysplenia syndrome. Our objective was to investigate the frequency and range of portal and other abdominal systemic venous anomalies in patients with polysplenia and inferior vena cava (IVC) interruption who underwent a cavopulmonary anastomosis procedure at our center, and to review the published literature on this topic and the potential clinical importance of such anomalies. Design. Retrospective cohort study and literature review were used. Results. Among 77 patients with heterotaxy, univentricular heart disease, and IVC interruption who underwent a bidirectional Glenn and/or modified Fontan procedure, pulmonary arteriovenous malformations were diagnosed in 33 (43%). Bilateral superior vena cavas were present in 42 patients (55%). Despite inadequate imaging in many patients, a partial PSVC, dual IVCs, and/or renal vein anomalies were detected in 15 patients (19%). A PSVC formed by a tortuous vessel running from the systemic venous system to the extrahepatic portal vein was found in six patients (8%). Abdominal venous anomalies other than PSVC were documented in 13 patients (16%), including nine (12%) with some form of duplicated IVC system, with a large azygous vein continuing to the superior vena cava and a parallel, contralateral IVC of similar or smaller size, and seven with renal vein anomalies. In patients with a partial PSVC or a duplicate IVC that connected to the atrium, the abnormal connection allowed right-to-left shunting. Conclusions. PSVC and other abdominal venous anomalies may be clinically important but under-recognized in patients with IVC interruption and univentricular heart disease. In such patients, preoperative evaluation of the abdominal systemic venous system may be valuable. More data are necessary to determine whether there is a pathophysiologic connection between the polysplenia variant of heterotaxy, PSVC, and cavopulmonary anastomosis-associated pulmonary arteriovenous malformations.