Intentional fracture of maximally dilated balloon-expandable pulmonary artery stents using ultra-high-pressure balloon angioplasty

Abstract

Background - Treatment with endovascular stents has become increasingly common for the management of vascular stenosis in congenital heart disease. The use of stents in smaller patients has been tempered by concerns about the potential for stent expansion to accommodate somatic growth. One solution to limited stent diameter is the intentional fracture of maximally dilated stents, which can be accomplished using ultra-high-pressure (UHP) balloons. Methods and Results - This retrospective cohort study compared procedural characteristics and adverse events between a cohort of patients with branch pulmonary artery (PA) stents who underwent stent fracture using UHP balloons and control patients who underwent UHP redilation of previously placed PA stents without stent fracture between 2004 and 2014. Two control patients were selected for every case. Thirty-three PA stents were fractured in 31 patients with a median of 10 years after initial stent placement. The median balloon:waist ratio was 1.17 (1-1.71), and the median inflation pressure was 20 (8-30) atm. There were significant reductions in pressure gradient after angioplasty, with no difference in postangioplasty gradients between cases and controls. There were no major PA complications in the stent fracture group and no difference in the number of adverse events between the 2 groups. Conclusions - In this small series, PA stent fracture using UHP balloon angioplasty was feasible and did not result in major complications although predictors of successful fracture were not identified. Intentional fracture with UHP balloon angioplasty may be considered when treating stents that have become restrictive despite maximal dilation.