Impact of intrapulmonary-artery septation to pulmonary vein obstruction for two-lung Fontan

Patients with unbalanced pulmonary artery (PA) growth and decreased unilateral pulmonary circulation are considered unsuitable candidates for the Fontan procedure. Following our previous study on the utility of intrapulmonary-artery septation for patients with PA hypoplasia, we investigated its use in patients with pulmonary venous obstruction (PVO).

We recruited 42 patients who underwent intrapulmonary-artery septation for unilateral PA hypoplasia and/or PVO between 1998 and 2018 and classified them into no PVO or PVO group. We analysed overall survival, success of the Fontan procedure and data from catheterization and echocardiography. In PVO, we evaluated the functional lung area before the Fontan procedure and the relevance of this parameter to operative outcomes.

The PVO and no-PVO group included 24 and 18 patients, respectively. One patient in the no-PVO and 6 patients in the PVO group died during follow-up; this difference was statistically significant (log-rank P = 0.040). In the no-PVO group, 15 (83%) patients achieved two-lung Fontan circulation. In the PVO group, 12 (50%) patients achieved two-lung Fontan circulation. Multivariate analysis revealed that functional lung area and shunt size [significantly larger in patients with functional lung area ≥50% in affected lung (P = 0.040)] were significant factors for successful two-lung Fontan procedure (P = 0.030).

Intrapulmonary-artery septation may contribute to increase functional lung area after PVO release to establish two-lung Fontan circulation in patients with PVO who have unbalanced PA growth and/or decreased unilateral pulmonary circulation.