REPEAT DILATION OF INTRAVASCULAR STENTS IN CONGENITAL HEART-DEFECTS

Background Intravascular (Palmaz) stents have been successfully implan ted in patients with congenital and acquired branch pulmonary stenosis . Early results are excellent; however, there is no information on res tenosis and repeat dilation in patients with congenital heart disease. The purpose of this study is to review the incidence of restenosis an d demonstrate the safety and efficacy of repeat dilation of stents in this group of patients. Methods and Results Of 94 patients with 163 im planted stents in this single-center study, 43 patients with 73 implan ted stents underwent recatheterization. Only 2 of 73 restudied stents (3%) developed significant restenosis. In 20 patients, 30 stents were redilated. At stent implantation, the mean age of this subgroup was 14 .2 years, the mean intraluminal diameter increased from 4.9 to 10.7 mm (P=.0001), and the systolic gradient (mean) across the stent decrease d from 52 to 11 mm Hg (P=.0001). At recatheterization (mean, 13 months ), all stents were patent. The mean diameter decreased by 1.2 mm (P=.0 001), but the increase in the gradient (mean, 3 mm Hg) was not signifi cant (P=.11). After repeat dilation, the diameter increased from 9.5 t o 12.2 mm (P=.0001), and the gradient decreased from 14 to 8 mm Hg (P= .0003). The 2 stents with restenosis were redilated successfully. Two patients underwent a successful second redilation of 3 stents at 18 an d 26 months. There were no complications. Conclusions All stents remai ned patent. The occurrence of significant restenosis is low (3%), and these restenoses can be redilated and/or restented. Repeat dilation of the Palmaz stent implanted in branch pulmonary artery stenosis can be per formed with safety and efficacy (94% success rate) up to 3 years after stent implantation.