Rotational Atherectomy for the Management of Undilatable In-Stent Restenosis with Single or Multiple Stent Layers.

<bold>Background: </bold>There is no consensus on the best treatment of undilatable coronary in-stent restenosis (ISR) regardless of the number of stent layers. We aimed to evaluate the procedural and clinical outcomes of rotational atherectomy (RA) to treat undilatable coronary ISR with single or multiple stent layers.<bold>Methods: </bold>We retrospectively evaluated consecutive patients treated with RA for undilatable ISR with single or multiple stent layers in the Mount Sinai catheterization laboratory between January 2016 and September 2018. Procedural success was defined as angiographic success without in-hospital major adverse cardiac events (MACE): a composite of death, myocardial infarction (MI), and target lesion revascularization (TLR). Clinical outcomes were assessed at one-year post-procedure.<bold>Results: </bold>A total of 26 patients were included in the study, in which 18 (69.2%) patients were with multiple stent layers. After RA, 9 (34.6%) were received a new drug-eluting stent, and 6 (23.1%) were treated with intravascular brachytherapy. Angiographic success was achieved in 24 (92.3%) patients, and procedural success was achieved in 22 (84.6%) patients. In-hospital MACE occurred in 4 (15.4%) patients, all due to periprocedural non-Q wave MI. Within one year, MACE occurred in 9 (34.6%) patients with 5 (19.2%) TLR.<bold>Conclusions: </bold>RA for undilatable ISR with single or multiple stent layers was performed with favorable procedural outcomes and a relatively high MACE rate driven by TLR within one year. [ABSTRACT FROM AUTHOR]