Balloon angioplasty with stent implantation in experimental coarctation of the aorta

Abstract

Background: Balloon angioplasty of coarctation of the aorta is an effective method of treatment but is complicated by tearing of the aortic intima, formation of aneurysms, and restenosis. Stent placement at the time of balloon dilation could prevent restenosis and could also prevent progression of intimal tears to aneurysms. The purpose of this study was to evaluate the feasibility of balloon dilation and implantation of balloon- expandable stents in an experimental model of coarctation and to examine the effect of stent placement at the site of surgically created stenosis. Methods and Results: Coarctation of the aorta was surgically produced in 11 juvenile swine. Simultaneous coarctation angioplasty and stent implantation was performed in 10 animals 34±7.8 days after surgery. Repeat catheterization was performed 59±6 days after stent implantation. Five animals underwent reexpansion of stents with subsequent follow-up catheterization. Aortic specimens were examined by light microscopy and scanning electron microscopy. Coarctation angioplasty with stent implantation was successful in all with an increase in coarctation diameter from 46±8.5% to 90±12.2% of proximal aortic diameter (P=.0001). Systolic pressure gradient decreased from 32±19.8 to 0.5±2.8 mm Hg (P