Prevalence, factors, and clinical impact of self-expanding stent fractures following iliac artery stenting

PurposeTo evaluate the prevalence, factors, and clinical impact of self-expanding stent fracture following iliac artery stenting.Materials and MethodsA review of the endovascular registry database for our department showed 353 patients with occlusive diseases of the iliac artery who underwent stenting between 1997 and 2007. While clinical data and images were retrospectively reviewed for all patients, 165 patients who underwent self-expanding stenting and plain radiograph with ≥6-months follow-up were analyzed. Mean follow-up was 43 months for 305 stents (elgiloy, n = 83; nitinol, n = 222) implanted in 216 iliac arteries. The mean duration until the last imaging study was 38 months. Items concerning prevalence of stent fracture, factors associated with fracture, and outcomes for patients with stent fracture were analyzed.ResultsStent fracture was detected in 11 of 216 iliac arteries (5.1%). In stent-based analysis, 11 of 305 stents (3.6%) showed stent fracture, classified as type I in 2 stents, type II in 3 stents, type III in 4 stents, type IV in 1 stent, and type V in 1 stent. Stent fracture was detected in 11 of 222 nitinol stents (5.0%), but no Elgiloy stents. Cox proportional hazards regression model indicated stenting for chronic occlusion as a risk factor associated with nitinol stent fracture (hazard ratio [HR] = 6.09, P = 0.008, 95% confidence interval [CI] 1.59-23.3). Cumulative primary patency rates in iliac arteries with and without fractured stents were 90% and 91% at 8 years (P = .80), respectively.ConclusionFracture of self-expanding stents is rare in iliac arteries, but stenting for chronic occlusion represents a risk factor for fracture. Fractures of stents placed in iliac arteries rarely affect patency.