Background:

The initial management of neonate patients with tetralogy of Fallot (TOF) associated with an unfavorable anatomy and significantly reduced pulmonary vascular flow is controversial and continues to be a clinical challenge.

Objective:

The aim of this study was to describe the clinical evolution and to compare pulmonary artery branch development in symptomatic neonatal TOF patients who received a modified Blalock Taussig shunt (mBT) versus right ventricular outflow tract stent placement (RVOTs) at the Department of Cardiology, Hospital de Niños de Córdoba, between March 2011 and March 2021.

Methods:

A retrospective, observational study identified 113 patients with TOF, 20 of which (18%) were symptomatic neonates requqiring initial palliative intervention. Categorical variables are expressed as percentage and continuous variables as median and interquartile range (IQR). A p value <0.05 was considered significant.

Results:

Among the 20 patients included in the study, 11 (55%) formed the mBT group and 9 (45%) the RVOTs group. In the mBT group, pre-palliative procedure right pulmonary artery (RPA) Z score was -3 (IQR 4.20) and increased to -1.6 (IQR 1.56) (p = 0.11) and left pulmonary artery (LPA) Z score of -2.5 (IQR 4.8) increased to -1.80 (IQR 2.36) (p = 0.44). In the RVOTs group, RPA Z score prior to palliative intervention was -3.45 (IQR 3.83) and increased to -2.5 (IQR 3.58) (p = 0.021) and LPA Z score of -4.10 (IQR 2.51) to -2.00 (IQR 3.75) (p = 0.011). Pre-intervention peripheral O2 saturation of 75% (IQR 6) increased to 87% (IQR 9) in the mBT group (p= 0.005) and from initially 75% (IQR 16) to 91% (IQR 13) in the RVOTs group (p= 0.008). Mean hospital stay after the procedure was 10 days (IQR 11) in the mBT group and 6 days (IQR 2) in the RVOTs group (p= 0.095).

Conclusions:

In symptomatic neonates with TOF, both palliative strategies improved the clinical condition. In patients who received RVOTs, there was greater development of pulmonary artery branches. A larger number of cases and longer-term follow-up will be necessary to confirm these findings.