In-Stent Restenosis: Pathophysiology and Treatment.

Management of in-stent restenosis (ISR) remains a clinical challenge after both bare metal stent and drug-eluting stent placement. Autopsy studies and intravascular imaging have augmented our understanding of the pathophysiology of ISR. The clinical presentation and symptoms vary considerably among patients from stable angina to unstable angina and acute myocardial infarction. Potential treatment strategies include plain old balloon angioplasty (POBA), rotational atherectomy, vascular brachytherapy (VBT), bare metal stents (BMS), drug-coated balloons (DCBs), and drug-eluting stent (DES) placement. The most efficacious therapy depends on patient and lesion characteristics, but drug-eluting stents and drug-coated balloons yield the most successful angiographic and clinical results. Here, we discuss the underlying pathology, risk factors, and clinical presentation of ISR while examining the evidence supporting the optimal interventional techniques for this commonly encountered clinical entity.