Early Results of Stent Implantation in Branch Pulmonary Artery Stenosis after Tetralogy of Fallot Repair

ABSTRACT

PURPOSE: Pulmonary artery stenosis is mainly complicated by aortopulmonary shunt or total correction of tetralogy of Fallot(TOF). Results of surgical angioplasty are poor and the success rate of balloon angioplasty is 53-72%. Endovascular stents have been applied to these lesions. The purpose of this study is to evaluate the early results of stent implantation in postoperative pulmonary artery stenosis in TOF. METHODS: Nineteen children with postoperative pulmonary artery stenosis were selected and balloon-expandable stent implantation was attempted between May 1994 and Feb 2000. For assessment of the results of stent implantation, the intraluminal diameter and the pressure gradient across the narrowest point were measured, as were the ratio of a right ventricle and aorta pressure, and a radionuclide lung perfusion scan was done before and after the procedure. RESULTS: Nineteen stents were implanted in 19 children, aged 2.3 years to 25,5 years. The increase of vessel diarneter ranged from 5.0+/-1.4mm to 10.7+/-2.1mm, pulmonary perfusion ratio from 16.7+/-5.3% to 29.2+/-10.0% and pressure gradients from 28.0+/-18.0 to 11.0+/-11.0mmHg with stent implantation. The systolic pressure ratio of the right ventricle and aorta decreased from 0.55+/-0.16 to 0.45+/-0.14. All above changes were statistically significant. Implantation failure occurred in 1 case and complications arose in 4 cases. CONCLUSIONS: The success rate of stent implantation is 94.296. Stent implantation is an effective and safe treatment method for postoperative pulmonary artery stenosis of TOF in short-term follow-up.