title: OCT imaging of aorto-coronary vein graft pathology modified by external stenting: 1-year post-surgery.
abstract: OBJECTIVE
  The Venous External Support Trial (VEST) evaluated whether a novel external stent attenuated saphenous vein graft (SVG) disease assessed with intravascular ultrasound 1 year following coronary artery bypass graft (CABG) surgery. This sub-study assessed SVGs with and without external stenting using optical coherence tomography (OCT). The aim of this study was to accurately compare quantitative and qualitative features of SVGs with and without a novel external stent using OCT.
  
  
  RESULTS
  Twenty-four of 30 patients (65 ± 8 years) enrolled in VEST underwent coronary angiography with OCT imaging using a non-occlusive technique. Quantitative analysis of lumen area was performed in one frame every 10 mm along the length of the graft, from distal to proximal anastomosis, and pathological features within the lumen were noted. Mean cross-sectional area was greater in unstented vs. stented grafts (8.4 ± 3 vs. 7.6 ± 2.7 mm; P = 0.005). The lumen of the stented grafts was more homogeneous (difference between maximum and minimum lumen diameter was significantly smaller in stented compared with unstented grafts, 0.28 ± 0.19 vs. 0.33 ± 0.23 mm, respectively, P = 0.006), and more circular (mean eccentricity index 0.08 ± 0.06 vs. 0.10 ± 0.06, stented vs. unstented; P = 0.019). Adherent thrombus was identified in three grafts (all unstented).
  
  
  CONCLUSIONS
  Our findings highlight the early changes occurring in SVGs after implantation of aorto-coronary bypass conduits, changes that may accelerate vein graft failure. External stenting resulted in a more homogeneous and less eccentric lumen with no thrombus formation.
authors.affiliation: Department of Cardiology, National Institute of Health Research Cardiovascular BRU, Royal Brompton Hospital, and the National Heart & Lung Institute, Imperial College London, London, UK c.webb@imperial.ac.uk.
authors.forename: Carolyn M
authors.initials: CM
authors.lastname: Webb
authors.affiliation: Vascular Graft Solutions, Tel Aviv, Israel.
authors.forename: Eyal
authors.initials: E
authors.lastname: Orion
authors.affiliation: Nuffield Department of Surgery, University of Oxford, John Radcliffe Hospital, Oxford, UK.
authors.forename: David P
authors.initials: DP
authors.lastname: Taggart
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK.
authors.forename: Keith M
authors.initials: KM
authors.lastname: Channon
authors.affiliation: Department of Cardiology, National Institute of Health Research Cardiovascular BRU, Royal Brompton Hospital, and the National Heart & Lung Institute, Imperial College London, London, UK.
authors.forename: Carlo
authors.initials: C
authors.lastname: Di Mario
mesh_terms: D000368:Aged; D003131:Combined Modality Therapy; D017023:Coronary Angiography / Q000379:methods; D001026:Coronary Artery Bypass / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006084:Graft Rejection; D006085:Graft Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment; D012501:Saphenous Vein / Q000000981:diagnostic imaging / Q000637:transplantation*; D012720:Severity of Illness Index; D015607:Stents; D041623:Tomography, Optical Coherence / Q000379:methods*; D016896:Treatment Outcome
keywords: bypass; imaging; stents; surgery; veins