title: Evaluation of below-the-knee drug-eluting stents with frequency-domain optical coherence tomography: neointimal hyperplasia and neoatherosclerosis.
abstract: OBJECTIVE
  To report the use of intravascular frequency-domain optical coherence tomography (FD-OCT) to detect and characterize in-stent neointimal tissue following infrapopliteal drug-eluting stent (DES) placement in patients suffering from critical limb ischemia.
  
  
  METHODS
  This prospective study included 12 patients (7 men; mean age 72.8±7.2 years) who had previously received 21 infrapopliteal sirolimus- or everolimus-eluting stents. The patients returned for regular angiographic follow-up or presented with clinical relapse of symptoms over a mean follow-up of 13.5±7.3 months (range 6-33), at which time FD-OCT imaging was performed. Study endpoints were technical imaging success, defined as successful FD-OCT acquisition and visualization of the arterial lumen and complete vessel wall, and the detection and characterization of in-stent neointimal hyperplasia according to widely accepted OCT criteria.
  
  
  RESULTS
  OCT imaging was successfully completed in 19 of the 21 stents. Binary in-stent restenosis (ISR>50%) was detected in 10/19 stents. Percent restenosis was higher after longer follow-up (60.6%±19.8% ≥1 year vs. 35.3%±20.6% <1 year, p=0.03) and in symptomatic vs. asymptomatic patients (61.5%±20.4% vs. 37.2%±19.3%, p=0.04). Neoatherosclerosis findings included lipid-laden neointima (16/19), neointimal neovascularization (13/19), neointimal calcifications (6/19), and thrombus (5/19); no cases of thin-cap fibroatheroma were identified. Neointimal calcifications were more frequent after ≥12 months of follow-up compared to <12 months (46.6% vs. 0%, p=0.02).
  
  
  CONCLUSIONS
  FD-OCT of the infrapopliteal arteries following DES placement is safe and feasible and may demonstrate features of developing neointimal neoatherosclerosis. The latter might play a key role as a mechanism of below-the-knee ISR and warrants further investigation.
authors: Department of Diagnostic and Interventional Radiology, Patras University Hospital, Patras, Greece. paraskevopoulosioannis@yahoo.gr
authors: Ioannis
authors: I
authors: Paraskevopoulos
authors: Stavros
authors: S
authors: Spiliopoulos
authors: Periklis
authors: P
authors: Davlouros
authors: Dimitrios
authors: D
authors: Karnabatidis
authors: Konstantinos
authors: K
authors: Katsanos
authors: Dimitrios
authors: D
authors: Alexopoulos
authors: Dimitrios
authors: D
authors: Siablis
mesh_terms: D000368:Aged; D050197:Atherosclerosis / Q000209:etiology* / Q000473:pathology*; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000209:etiology; D007511:Ischemia / Q000601:surgery*; D007866:Leg / Q000098:blood supply*; D008297:Male; D058426:Neointima / Q000473:pathology*; D011183:Postoperative Complications / Q000473:pathology*; D011446:Prospective Studies; D041623:Tomography, Optical Coherence