Fate of Duct-Dependent, Discontinuous Pulmonary Arteries After Arterial Duct Stenting.

Significant and balanced PA growth following arterial duct (AD) stenting has already been consistently reported in literature. However, to date, no data are available about the role of this approach as palliation of congenital heart disease with a duct-dependent discontinuous pulmonary artery (dPA). The aim of this study was to evaluate the fate of a dPA of ductal origin following trans-catheter AD stabilization. Angiographic PA evaluation was performed in seven patients submitted to neonatal AD stenting as palliative recruitment of dPA. Five patients showed discontinuity of one PA, while two patients had both PAs served by bilateral ducts. PA growth was evaluated as per the Nakata index, McGoon ratio as well as dPA (n = 9) versus heart-dependent PA (hPA; n = 5) size and z-score changes. AD stabilization was performed using coronary stents dilated to 3.2 ± 0.3 mm (median 3.4), with significant increase of O2 saturation (from 83 ± 11 to 95 ± 5%, p < 0.02). Control angiography was performed 5.1 ± 2.8 months (median 6 months) after duct stenting, showing significant growth of the dPA (from 3.7 ± 1.0 to 7.6 ± 2.7 mm, p < 0.001; z-score from -0.7 ± 1.4 to 1.7 ± 2.2, p < 0.01). A trend toward better growth of the dPA as compared with the hPA was found (117 ± 87 vs. 54 ± 34%, p = NS). The final vessel size was still significantly different between the groups (dPA 7.6 ± 2.7 vs. hPA 11.9 ± 3.4 mm, p = 0.02), although the final z-score value did not significantly differ (dPA 1.7 ± 2.2 vs. hPA 3.8 ± 0.9 mm, p = NS). In conclusion, percutaneous AD stenting is effective in promoting a significant catch-up growth of duct-dependent dPA, being, therefore, advisable as a reliable alternative to surgical palliation.