# Comparative Study on the Outcomes of Right Ventricular Outflow Tract Stenting vs. Modified Blalock-Taussig Shunt in Patients with Tetralogy of Fallot: A Prospective Randomized Trial

## TL;DR

This study compares two surgical treatments for tetralogy of Fallot in infants, finding that stenting leads to better pulmonary artery growth than a shunt.

## Contribution

A novel prospective randomized trial comparing right ventricular outflow tract stenting and modified Blalock-Taussig shunt outcomes in Tetralogy of Fallot.

## Key findings

- Stenting led to significantly greater increases in Nakata index compared to shunt placement.
- Pulmonary artery growth rates were higher in the stent group for both right and left arteries.
- Complete correction procedures were similarly frequent between the two groups.

## Abstract

To evaluate pulmonary vascular development and outcomes of complete
correction following palliative treatment in infants with critical tetralogy
of Fallot.

This prospective, randomized, two-center study included infants with
tetralogy of Fallot who underwent surgery between June 2018 and 2022. The
patients were divided into two groups - those who underwent stenting of the
right ventricular outflow tract (stent group, n=21) and those who underwent
modified Blalock-Taussig shunt placement (shunt group, n=21).

In the stent group, a significantly greater increase in Nakata index was
observed, with mean values rising from 104.2 to 208.6
mm2/m2, compared to an increase from 107.3 to
169.4 mm2/m2 in the shunt group (P<0.01). According
to the mixed model analysis, the rate of growth of the right pulmonary
artery in the stent group was 2.05*10-2 z score/day, which was 3.01 times
greater than that in the shunt group (P<0.01). The rate of growth of the
left pulmonary artery in the stent group was 2.3*10-2 z score/day, which was
1.47 times greater than that in the shunt group (P<0.01). In one patient
(4.8%), after 76 days following the stenting of the RVOT, a severe
infectious process with sepsis occurred, leading to a fatal outcome.
Complete correction in the stent group involved transannular patch repair of
the right ventricular outflow tract to the pulmonary artery in 12 patients
(60%), while the same procedure was performed in 15 patients (71.4%) in the
shunt group (P=0.52).

Stenting of the right ventricular outflow tract provides hemodynamic
stabilization and symmetric growth of the pulmonary vascular bed compared to
the formation of a modified Blalock-Taussig shunt.