Self-expandable stents for the treatment of iliac artery obstructive lesions: long-term success and prognostic factors.

OBJECTIVE: The purpose of our study was to report long-term (more than 2 years of follow-up) angiographic patency after self-expandable stent implantation in the iliac artery and to identify patient- or procedure-related prognostic factors of angiographic patency. SUBJECTS AND METHODS: Ninety-five consecutive patients (101 arteries) underwent Wallstent implantation to treat claudication (n=95 limbs), rest pain (n=2), and nonhealing ulcer (n=3). Another patient was asymptomatic but was treated for acute occlusion of the iliac artery after coronary angioplasty. After implantation of self-expandable stents, we followed up by examining clinical and angiographic records at 6 months, 1 year, and annually thereafter. The Kaplan-Meier survival curve was used to determine primary and secondary patency rates. Primary patency was that achieved after the initial procedure only. Secondary patency was defined as that achieved after one or more successful additional percutaneous procedures within the stent or beyond the stent. Multivariate analysis using the Cox proportional hazard model was performed to identify predictive factors of angiographic failure, defined as restenosis of 50% or greater or occlusion.
RESULTS: Four-year patency rates of 61% (primary) and 86% (secondary) were found (mean follow-up, 29 months). The following five factors were associated with long-term angiographic failure: occlusion of the superficial femoral artery (relative hazard = 5.21), absence of hypertension (relative hazard = 4.85), a stent diameter of less than 8 mm (relative hazard = 4.45), two or more stents implanted (relative hazard = 3.56), and current tobacco consumption (relative hazard = 2.46).
CONCLUSION: Improved patency rates may be obtained by selecting patients for Wallstent implantation in the iliac artery based on five factors shown to be prognostically important.