Anatomic and technical predictors of stent malposition during implantation for vascular obstruction in patients with congenital and acquired heart disease.

OBJECTIVES We evaluated the anatomic and technical factors predicting stent malposition and embolization in patients undergoing endovascular stent implantation for relief of noncoronary vascular obstruction. BACKGROUND Endovascular stent implantation provides a highly effective, minimally invasive solution to vascular obstruction in patients with structural heart disease. However, stent implantation is technically challenging and stent embolization occurs in up to 5.5% of cases. METHODS We reviewed patient and procedural characteristics of all endovascular stent implantations performed for relieving noncoronary vascular obstruction from January 1, 1999, through December 31, 2009. Univariate and multivariate predictors of stent malposition or embolization were explored through logistic regression methods. RESULTS During the 10-year study period, 429 stents were implanted. Of these, 399 were placed for relief of vascular obstruction in 267 patients during 322 procedures. Initial implantation failure occurred in 33 patients (8.3%), including stent malposition in 18 (4.5%) and stent embolization in 15 (3.8%). Patient size and vascular obstruction caused by external compression or a vascular fold were independent predictors of stent malposition or embolization. All malpositioned and embolized stents were successfully managed without surgery, and none resulted in death, sustained hemodynamic instability, or important vascular injury. CONCLUSIONS Endovascular stent implantation is a highly effective and safe means of relieving noncoronary vascular obstruction in patients with congenital and acquired structural heart disease. Stent embolization occurs in approximately 3.8% of implantation procedures but can be managed successfully without surgical intervention. Anatomic and technical factors predict stent malposition, and consideration of these factors may improve procedural results.