Evaluation of the Safety and Effectiveness of Renal Artery Stenting After Unsuccessful Balloon Angioplasty: The ASPIRE-2 Study

Abstract

Conclusion: Balloon-expandable stents in hypertensive patients with ostial renal artery atherosclerotic stenosis can have a beneficial impact on hypertension when initial transluminal angioplasty is unsuccessful. Summary: The authors sought to define safety and durability of renal artery stents following suboptimal or failed renal artery angioplasty when renal vascular hypertension was suspected. This was a non randomized study that enrolled 208 patients with either primary or restenontic (>70%) ostial renal artery stenosis. All patients underwent placement of a balloon-expandable stent following an unsuccessful transluminal angioplasty. Unsuccessful transluminal renal artery angioplasty was defined as >50% residual stenosis, flow limiting dissection, or a persistent trans-lesion pressure gradient. Primary end point was restenosis at 9 months as determined by angiogram or duplex scanning. Secondary end points included blood pressure, cumulative adverse events, renal function, and target lesion revascularization at 24 months. In 80.2% of cases, placement of the stent was immediately successful (n = 182 of 227). Nine month restensosis rate was 17.4%. Systolic blood pressure decreased from 168 ± 25 mm/Hg at baseline to 149 ± 24 mm/Hg at 9 months and 149 ± 25 mm/Hg at 24 months (P < .001). At 24 months, the cumulative rate of major adverse events was 19.7%. Serum creatinine concentrations were unchanged from baseline values at both 9 and 24 months. Comment: The study is limited by its retrospective nature and lack of controls in that no patients were treated with medical therapy or simple balloon angioplasty alone. In addition, primary stenting of renal artery ostial lesions is currently routine. The study provides reasonable information regarding recurrent stenosis in a sub group of patients undergoing renal artery stenting. Overall, however, it is of little relevance to modern practice.