Abstract
Intracoronary in-stent restenosis (ISR) is a phenomenon that generally occurs between 3 and 6 months after stent placement. With the introduction of drug-eluting stents (DES), the incidence of ISR has decreased but not disappeared. We report a case of reiterant in-stent restenosis of an 81-year-old female patient who underwent multiple percutaneous coronary intervention and two coronary artery bypass surgeries. ISR is possibly associated with extra-stent, stent-related and intra-stent factors. Here, we excluded the first two and focused on the intra-stent factors that seem more likely in our case. A challenging diagnostic workup led us to the hypothesis of a coronary vasculitis potentially triggered by some component of the stent in a predisposed patient carrier of non-disease-specific ANA, with an exaggerated immune response. No recurrence of ISR occurred after the introduction of steroids. Biological and intra-stent causes of ISR should be taken into careful consideration to aim for the early detection of the underlying mechanism of restenosis and to embrace the best therapeutic strategy. LEARNING POINTS: Intra-stent restenosis is possibly associated with extra-stent, stent-related and intra-stent factors.Coronary vasculitis is potentially triggered by some component of the stent in a predisposed patient.Immunosuppressive treatment should be taken into consideration in case of recurrent intra-stent restenosis.