COMPARISON OF LONG-TERM RESULTS OF A PHASED APPROACH WITH STENTING OF THE RIGHT VENTRICULAR OUTFLOW TRACT AND ONE-STAGE RADICAL CORRECTION IN CHILDREN WITH TETRALOGY OF FALLOT
Authors: Lyapin Anton A. , Tarasov Roman S. 
Published: July 2024

Highlights

Right ventricular outflow tract stenting in children with the tetrad of Fallot as a palliative stage allowed to perform radical correction of the malformation effectively and safely afterwards.

 

Abstract

Aim. Evaluation of short-term and long-term results of a phased correction of the tetrad of Fallot (ToF) with stenting of the right ventricular outflow tract (RVOT) in comparison with a one-stage radical correction (RC) of the defect.

Methods. Two groups of patients with classical ToF were formed. Group 1 (n = 25; median age 72 days) was initially represented by children with ToF with a more severe clinical status, many of them were premature (median weight 3.8 kg), with more pronounced cyanosis; there were prenatal lesions of the central nervous system, brain malformations, intrauterine development delays. The children of group 1 underwent the first stage of RVOT stenting, and the second stage of RC ToF. Group 2 (n = 25) was represented by older patients, with a higher body weight and SpO2 level, and they underwent a single-stage RC of the defect.

Results. The application of a step-by-step ToF correction approach with RVOT stenting in low-weight newborns with severe hypoxemia demonstrated an equivalent effect on SpO2 dynamics, reverse remodeling of the heart when compared with a less severe cohort of patients who underwent simultaneous RC of classical ToF. After RVOT stenting in children from group 1, the median SpO2 increased from 80% to 94.5%, the median Z value of the pulmonary artery (PA) trunk of the from 16.1 mm to 16.9 mm, the median index of end-diastolic volume (EDV) of left ventricle (LV) from 23.07 mm/m2 to 57.6 ml/m2. Initially, groups of children who were not equivalent in their clinical status practically leveled off in terms of their indicators after RVOT stenting with patients undergoing simultaneous RC of ToF. In group 2, at the time of the RC of defect, the median SpO2 was 94%, the median Z value of the PA trunk was 15.4 mm, and the median index of EDV of LV was 57.6 ml/m2. RC ToF in children from group 1 with a phased strategy of correction of the defect was no less successful than in children who underwent simultaneous RC. In the long-term follow-up period, children after RC ToF from groups that were obviously unequal in their initial status were practically comparable in clinical characteristics, features of cardiac remodeling, and achievement of endpoints. In assessing the long-term results, we focused on such endpoints as: death from all causes (3 in the RVOT stenting group and 1 in the simultaneous RC group), re-operations for the underlying disease were not performed in any case, cardiac conduction disorders requiring the installation of a cardiac pacemaker (one child in each group), acute cerebrovascular accident was observed in only one child from group 2. And there were no significant differences between the two groups in the frequency of reaching the endpoints during the annual, three-year and five-year follow-up period.

Conclusion. The strategy of RVOT stenting followed by RC ToF in a severe group of children demonstrated comparable results compared with the results of simultaneous RC of ToF in a more stable group of patients during the hospital, annual, three-year and five-year follow-up period.