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.

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.

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