Prior Innominate Vein Occlusion Does Not Preclude Successful Bidirectional Superior Cavopulmonary Connection

Low superior vena cava (SVC) blood flow has recently been identified as a marker for bidirectional superior cavopulmonary connection (SCPC) failure and death. Prior innominate vein occlusion is considered a significant anatomic risk factor for SCPC failure. We therefore evaluated the outcomes of infants who underwent SCPC with known upper-body venous obstruction.

Between February 1995 and June 2014, SCPC was carried out in 8 patients who had either a single SVC with known prior occlusion of the innominate vein (n = 6) or bilateral SVCs without a bridging vein with occlusion of one SVC (n = 2). The cause of the occlusion was an indwelling catheter in 5 patients. These patients were compared with 8 patients with normal upper-body venous drainage who underwent SCPC. Patients were evaluated for preoperative risk factors (including SVC size, pulmonary artery size, Nakata index, pulmonary vascular resistance), operative factors, and clinical outcomes to determine the impact of prior upper-body venous occlusion on SCPC failure or death.

There were no significant differences in preoperative risk factors between the two groups, except for a significantly lower Nakata index in the study group with a trend toward smaller pulmonary artery branch size. There were no SCPC takedowns or mortalities. There was no significant difference in postoperative length of stay (median of 7 days [range, 5 to 32 days] versus 5 days [range, 4 to 32 days]; p = 0.17. Study patients had a lower mean systemic oxygen saturation at discharge, 81% versus 85% (p = 0.05). In the study group, at a median follow-up of 42 months, 3 patients underwent successful Fontan completion and 5 are still awaiting Fontan completion.

Although patients with prior upper-body venous obstruction may have lower systemic oxygen saturations at hospital discharge, they do not demonstrate an increased SCPC failure or mortality rate. Innominate vein occlusion or its equivalent in patients with bilateral SVCs should not preclude the performance of SCPC. Physiologic rather than anatomic evaluation of preoperative systemic venous return may be more useful to predict outcome after SCPC.