title: Diagnostic accuracy of optical coherence tomography parameters in predicting in-stent hemodynamic severe coronary lesions: validation against fractional flow reserve.
abstract: BACKGROUND
  By means of optical coherence tomography (OCT), coronary dimensions can be assessed accurately. However, whether OCT can identify hemodynamic significant coronary lesions as determined by fractional flow reserve (FFR) in patients with an in-stent lesion is not known. Therefore, we tried to assess the predictive value of OCT parameters in this setting as compared to FFR.
  
  
  RESULTS
  In patients who underwent a percutaneous coronary intervention for an in-stent restenotic lesion, pre-, post-procedural and 6-month follow-up OCT and FFR acquisitions were performed. In case of an FFR ≤ 0.80, a lesion was classified as hemodynamically severe. Diagnostic efficiency of several OCT parameters were assessed with receiver operating characteristic curves. In 27 patients, 66 coupled OCT and FFR segments were analyzed and compared. The diagnostic efficiencies of OCT-based minimal luminal diameter (MLD) and minimal luminal area (MLA) are good, with an area under the curve (AUC) of 0.83 (95% confidence interval: 0.74-0.93) and 0.83 (0.73-0.93), and a best cutoff value of 1.77 mm (sensitivity 74% and specificity 78%) and 2.54 mm(2) (sensitivity 71% and specificity 84%), respectively. The diagnostic efficiency of OCT-based maximum neointimal area is moderate [AUC 0.73 (0.61-0.85)], and regarding maximum neointimal area stenosis, it is poor [0.39 (0.25-0.53)]. The corresponding best cutoff values are 5.01 mm(2) (sensitivity 66% and specificity 72%) and 49% (sensitivity 40% and specificity 66%), respectively.
  
  
  CONCLUSIONS
  With OCT, a good diagnostic efficiency can be achieved in identifying coronary severity in in-stent lesions in a per-group analysis. This hallmark provides an extra dimension, next to morphological information, when acquiring OCT images in scientific studies. However, OCT seems limited in a per-patient clinical decision making process due to reasonable but limited sensitivity and specificity in predicting coronary severity.
authors: Department of Cardiology, University Medical Center Utrecht, Utrecht, Netherlands.
authors: Anouar
authors: A
authors: Belkacemi
authors: Pieter R
authors: PR
authors: Stella
authors: Danish S
authors: DS
authors: Ali
authors: Putri W
authors: PW
authors: Novianti
authors: Pieter A
authors: PA
authors: Doevendans
authors: Eric
authors: E
authors: van Belle
authors: Pierfrancesco
authors: P
authors: Agostoni
mesh_terms: D000368:Aged; D023903:Coronary Restenosis / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012042:Registries; D015607:Stents / Q000009:adverse effects; D041623:Tomography, Optical Coherence / Q000592:standards*
keywords: Fractional flow reserve; In-stent restenosis; Optical coherence tomography