Refractory In-Stent Restenosis: Improving Outcomes by Standardizing Our Approach.

PURPOSE OF REVIEW: This review will focus on our approach for the treatment of refractory in-stent restenosis.

RECENT FINDINGS: The discovery of bare metal stents over three decades ago set a milestone in the evolution of percutaneous coronary intervention, which is currently the most widely performed procedure for the treatment of symptomatic coronary disease. However, the broad utilization of stents resulted in the new phenomenon of in-stent restenosis (ISR). Over the years, there has been an increase of the incidence of ISR despite continued improvement of drug-eluting stent (DES) technology. The mechanism of ISR is multifactorial, including biological, mechanical, patient, and operator-related factors. The most common factor is aggressive neointimal proliferation and neoatherosclerosis. ISR presentation is not benign, and treatment is challenging, especially in cases of DES-ISR. We review available therapy modalities for ISR, including medical therapy, scoring balloons, atheroablative therapies, repeat DES, vascular brachytherapy, drug-coated balloons, and coronary artery bypass grafting.