July 14, 2004

Restenosis In Gold Coated Renal Stents

Brian W Nolan, Marc Schermerhorn, Richard Powell, Erin Rowell, Mark Fillinger, Eva Rzucidlo, Mark Wyers, David Whittaker, Daniel Walsh, Robert Zwolak, Jack Cronenwett
Dartmouth Hitchcock Medical Center, Lebanon, NH

Introduction: Gold-coating improves stent visibility under fluoroscopy. This is particularly valuable for precise stent placement during renal artery stenting (RAS). There is conflicting evidence however regarding restenosis with gold-coated stents. To evaluate the effect of gold coating on restenosis after renal stenting, we reviewed the results of all patients undergoing RAS in our practice.

Methods: A retrospective cohort study of all patients undergoing RAS between June 2000 and September 2003 was performed. Restenosis (>60% diameter) was determined by serial follow-up duplex exams (peak systolic velocity>180cm/s and renal aortic ratio>3.5). Restenosis rates were determined using the Kaplan-Meier life-table method. Other variables potentially affecting restenosis were evaluated with the log rank test and Cox proportional hazards modeling.

Results: RAS was performed in 97 arteries (78 patients). Gold-coated stents were placed in 59 arteries (48 patients). Stainless steel stents were placed in 38 arteries (30 patients). Patient demographics, indication for treatment, technical success and complications did not differ between gold and stainless steel stent groups. Mean follow-up was 340 + 225-days for gold stents and 441 + 383-days for stainless steel stents (difference not significant). The overall 1-year restenosis rate was 30%; 15% in arteries treated with stainless steel stents and 41% in arteries with gold stents (p=0.007; hazard ratio 4.6, 95% CI 1.3 to 15.6). Stent diameter, gender, age, indication for RAS, and diabetes had no effect on restenosis by univariate analysis. By multivariate analysis only gold-coated stents predicted restenosis (p=0.004). There were no significant differences in clinical outcomes other than restenosis (blood pressure and renal function) between the two groups.

Conclusion: Gold-coated stents had a substantially higher rate of restenosis than stainless steel stents in our series. Patients receiving gold-coated stents for the treatment of atherosclerotic renal artery stenosis should be followed closely for evidence of restenosis.