Evaluation of the safety and effectiveness of renal artery stenting after unsuccessful balloon angioplasty: the ASPIRE-2 study.

OBJECTIVES: This study sought to define the safety and durability of renal stenting after suboptimal/failed renal artery angioplasty in patients with suspected renovascular hypertension.

BACKGROUND: Few prospective multicenter studies have detailed the safety, efficacy, and long-term clinical benefits of renal artery stent revascularization in hypertensive patients with aorto-ostial atherosclerotic renal artery lesions.

METHODS: This non-randomized study enrolled 208 patients with de novo or restenotic > or = 70% aorto-ostial renal artery stenoses, who underwent implantation of a balloon-expandable stent after unsuccessful percutaneous transluminal renal angioplasty (PTRA), which was defined as a > or = 50% residual stenosis, persistent translesional pressure gradient, or a flow-limiting dissection. The primary end point was the nine-month quantitative angiographic or duplex ultrasonography restenosis rate adjudicated by core laboratory analysis. Secondary end points included renal function, blood pressure, and cumulative incidence of major adverse events and target lesion revascularization at 24 months.

RESULTS: The stent procedure was immediately successful in 182 of 227 (80.2%) lesions treated. The nine-month restenosis rate was 17.4%. Systolic/diastolic blood pressure decreased from 168 +/- 25/82 +/- 13 mm Hg (mean +/- standard deviation) at baseline to 149 +/- 24/77 +/- 12 mm Hg at 9 months (p < 0.001 vs. baseline), and 149 +/- 25/77 +/- 12 mm Hg at 24 months (p < 0.001 vs. baseline). Mean serum creatinine concentration was unchanged from baseline values at 9 and 24 months. The 24-month cumulative rate of major adverse events was 19.7%.

CONCLUSIONS: In hypertensive patients with aorto-ostial atherosclerotic renal artery stenosis in whom PTRA is unsuccessful, Palmaz (Cordis Corp., Warren, New Jersey) balloon-expandable stents provide a safe and durable revascularization strategy, with a beneficial impact on hypertension.