Optical coherence tomography: guided therapy of in-stent restenosis for peripheral arterial disease.

Approximately 27 million people in Europe and North America currently have peripheral arterial disease (PAD). The endovascular treatment of stenosis or blocked peripheral arteries in PAD include percutaneous transluminal angioplasty with or without a drug coated balloon (DCB), atherectomy (rotational, directional, orbital or laser), and stenting. The development of next generation peripheral stents and drug-coated stents have led to the improved treatment of complex superficial femoral artery (SFA) lesions, and consequently increased their usage. Additionally, the technologies developed for PAD intervention have further improved the overall adoption of endovascular procedures leading to increased utilization of stents to address procedural dissections (bailout stenting), as support scaffolding for complex lesions, and to prevent preventing elastic recoil post balloon angioplasty. For example, bail-out stenting after DCB angioplasty has been reported to be as high as 40% in long lesions and as high as 46% in chronic total occlusions lesions. In total, approximately 200,000 stents are placed annually in the femoral and popliteal arteries in PAD patients in the USA, with 30% to 40% of these stents expected to develop in-stent restenosis within 2-3 years of implantation. Accordingly, the treatment of in-stent restenosis (ISR) remains a substantial healthcare burden. Few technologies reported on improved ISR patency rates as compared to PTA treatment alone, including drug-eluting stents and balloons, laser atherectomy or covered stents. However, the reported longer-term patency for ISR remains suboptimal creating a cyclical treatment pattern that burdens patients and providers. In this review, we present the rational and clinical evidence for utilizing OCT-guided therapies for the treatment of ISR for PAD.