Abstract
The unique physical properties of optical coherence tomography (OCT) make it a useful technique in the study of restenosis mechanisms. In fact, OCT is able to differentiate between neointimal proliferation and neoatherosclerosis within the stent. We report a rare case of occlusive neoatherosclerosis presenting beyond one year after a successful drug-eluting stent implantation. The impact of OCT findings in the clinical decision making process is emphasized.
Highlights
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Optical coherence tomography (OCT) has the unique ability to detect lipid accumulation within the stent margins (i.e. neoatherosclerosis).
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Lipid-rich tissues produce light absorption and therefore they typically attenuate backward signals.
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Occlusive neoatherosclerosis may appear even in optimally implanted drug eluting stents.
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OCT identification of restenosis mechanisms may have implications not only in the interventional strategy, but also in the long-term medical treatment.
Neoatherosclerosis, characterized by the accumulation of macrophages and the formation of a lipid pool within the stent margins, constitutes a specific cause of late stent failure. The identification of this phenomenon can have an impact on technical aspects of coronary interventions as well as on long-term medical treatment.
A 66-year-old man with long-standing diabetes mellitus underwent successful left-circumflex everolimus-eluting TAP stenting due to silent restenosis at the side branch of a prior left main bifurcation provisional stenting ( Fig. 1 A , Video 1 ). During the following year, treatment included aspirin, prasugrel and atorvastatin 80 mg, with ezetimibe subsequently added due to LDL-cholesterol of 83 mg/dL despite high-dose statin therapy.
Sixteen months after the procedure, the patient complained of vigorous efforts stable angina, with no episodes at rest, and presented with a normal electrocardiogram and biomarkers. The exercise stress test was positive, and coronary angiography revealed an occlusive restenosis of the circumflex stent ( Fig. 1 B, Video 2 ). After conservative lesion predilatation with a 1.5 mm balloon, optical coherence tomography (OCT) was performed (ILUMIEN™ OPTIS™, St. Jude Medical, Inc., St. Paul, MN). This study identified neoatherosclerosis as the main mechanism of late in-stent restenosis, depicting a lipid-rich material with light attenuation in deep layer and shadowing the underlying stent struts. It also showed good stent expansion and nice adjustment to the vessel ostium ( Fig. 2 , Video 3 ). The patient was treated with a polymer-free biolimus-eluting stent with good final result.
