Experience of Stent Implantation in Branch Pulmonary Artery Stenosis of the Congenital Heart Disease

Yun, Yong Soo; Cheon, Eun Jung; Kim, Ho Sung; Noh, Chung Il; Choi, Jung Yun

Abstract

PURPOSE
Branch pulmonary artery stenosis remains a clinically challenging lesion. Results of surgical angioplasty are rarely rewarding, and balloon angioplasty is not uniformly successful. So, endovascular stent has been applied recently to these lesions. But this new modality has not been fully evaluated. The aim of this study is to evaluate the short-term result of stent implantation in postoperative branch pulmonary artery stenosis.
METHODS
In selected 17 children with postoperative branch pulmonary artery stenosis, balloon-expandable stent implantation were attempted between Aug. 1993 and Feb.1996. They all had Tetralogy of Fallot except one with ventricular septal defect and pulmonary atresia and had been underwent total correction. For assessment of results of stent implantation, intraluminal diameter ratio (LPA/RPA) and pressure gradient across the narrowest point were measured, and radionuclide lung perfusion scan was done before and after the procedure.
RESULTS
Fifteen stents were successfully implanted in each 15 children, aged 3.4 years to 12.7 years. The average ratio of vessel diameter (LPA/RPA) on angiogam increased from 0.49+/-0.15 to 0.96+/-0.18, pulmonary perfusion fraction from 25.6+/-6.1 to 38.9+/-9.9% and pressure gradients from 19.0+/-8.5mmHg to 7.4+/-6.0mmHg with stent placement. All changes were statistically significant. There were no fever, transfusion requirement, femoral artery thrombosis, and transient bradycardia during the procedure. Implantation failure was two cases. Failure was due to displacement of stent to distal pulmonary artery.
CONCLUSIONS
Success rate of stent implantation is 88%. Effective relief of stenosis is accomplished in 93%. Stent implantation is effective and safe modality for postoperative branch pulmonary artery stenosis in short-term follow-up.