Arguments against conventional balloon dilatation of recurrences within the stent

Abstract

Today, stent restenosis is the major limitation of coronary stent implantation. Despite several prospective randomized trials, which documented significantly lower restenosis rates after stenting compared to conventional balloon angioplasty for the treatment of de-novo stenoses, restenotic lesions, bypass graft stenoses and symptomatic dissections, in daily clinical practice restenosis rates after coronary stenting are reported between 18% and 78% depending on the lesions treated. Interventional treatment options for symptomatic stent restenosis include repeat balloon angioplasty, a combination of ablative approaches (rotablation, laser angioplasty, directional atherectomy) with balloon angioplasty, and stent-in-stent (sandwich technique) placement. Long-term success for the treatment of focal (< or = 10 mm) stent restenosis seems to be equivalent for all these strategies with a restenosis rate of about 30% while after balloon angioplasty of diffuse (> 10 mm) stent restenosis restenosis rates range between 35% and 85%. From a pathophysiological point of view it seems conclusive that balloon angioplasty can only achieve a limited lumen by plastic deformation of the obstructive neointimal tissue, which is responsible for stent restenosis. In this situation techniques, which ablate the neointimal tissue, can create a more adequate lumen without extensive vessel trauma supported by lower restenosis rates between 25% and 56% compared to balloon angioplasty alone. Prospective randomized trial are needed in the future to support a superiority of ablative techniques over conventional balloon angioplasty for the treatment of stent restenosis.