title: Accuracy of intravascular ultrasound and optical coherence tomography in identifying functionally significant coronary stenosis according to vessel diameter: A meta-analysis of 2,581 patients and 2,807 lesions.
abstract: BACKGROUND
  Accuracy of intracoronary imaging to discriminate functionally significant coronary stenosis according to vessel diameter remains to be defined.
  
  
  METHODS
  PubMed, Scopus, and Google Scholar were systematically searched for studies assessing diagnostic accuracy (area under the receiver operating characteristic curve [AUC], the primary end point) and sensitivity and specificity (the secondary end points) of minimal luminal area (MLA) or of minimal luminal diameter (MLD) derived from intravascular ultrasound (IVUS) or optical coherence tomography (OCT) to detect functionally significant stenosis as determined with fractional flow reserve (FFR).
  
  
  RESULTS
  Fifteen studies were included, 2 with 110 patients analyzing only left main (LM), 5 with 224 patients and 306 lesions using OCT, and 9 with 1532 patients and 1681 lesions with IVUS. Median MLA for the OCT studies was 1.96 mm(2) (1.85-1.98 mm(2)), 2.9 mm(2) (2.7-3.1 mm(2)) for MLA of all lesions assessed with IVUS, 2.8 mm(2) (2.7-2.9 mm(2)) for lesions with an angiographic diameter >3 mm, 2.4 mm(2) (2.4-2.5 mm(2)) for lesions <3 mm, and 5.4 mm(2) (5.1-5.6 mm(2)) for LM lesions. For OCT-MLA, AUC was 0.80 (0.74-0.86), with a sensitivity of 0.81 (0.74-0.87) and specificity of 0.77 (0.71-0.83), whereas OCT-MLD had an AUC of 0.85 (0.79-0.91), sensitivity of 0.74 (0.69-0.78), and specificity of 0.70 (0.68-0.73). For IVUS-MLA, AUC was 0.78 (0.75-0.81) for all lesions, 0.78 (0.73-0.84) for vessels with a diameter >3 mm, and 0.79 (0.70-0.89) for those with a diameter <3 mm. Left main AUC was 0.97 (0.93-1).
  
  
  CONCLUSIONS
  Intravascular ultrasound and OCT had modest diagnostic accuracy for identification hemodynamically significant lesions, also with specific cutoff for different diameters. Invasive imaging for assessment of LM severity demonstrated excellent correlation with FFR. What is already known about this subject? Fractional flow reserve represents the criterion standard to evaluate the prognostic value of coronary stenosis, whereas its relationship with IVUS and OCT remains to be assessed. What does this study add? Despite improvement, IVUS and OCT do not predict functional stenosis, even with dedicated cutoff, apart from LM disease. How might this impact on clinical practice? The recent guidelines of myocardial revascularization have stressed the crucial role of FFR before performing percutaneous coronary intervention on LM, whereas intravascular imaging is often exploited to drive revascularization. The present analysis stresses the point that LM percutaneous coronary intervention may be driven only by intravascular imaging, given the high accuracy for significant ischemic lesions, whereas for other vessels, these 2 techniques mirror 2 different aspects.
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy. Electronic address: fabrizio.dascenzo@gmail.com.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: D'Ascenzo
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Umberto
authors.initials: U
authors.lastname: Barbero
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Cerrato
authors.affiliation: Division of Cardiology, Medstar Washington Hospital Center, Washington, DC.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lipinski
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Omedè
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Montefusco
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Salma
authors.initials: S
authors.lastname: Taha
authors.affiliation: Department of Cardiology,University Hospital of the RWTH Aachen, Aachen, Germany.
authors.forename: Toru
authors.initials: T
authors.lastname: Naganuma
authors.affiliation: Global Genomics Group, Richmond, VA.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Reith
authors.affiliation: Interventional Cardiology Unit, San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Szilard
authors.initials: S
authors.lastname: Voros
authors.affiliation: Department of Cardiology,University Hospital of the RWTH Aachen, Aachen, Germany.
authors.forename: Azeem
authors.initials: A
authors.lastname: Latib
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Nieves
authors.initials: N
authors.lastname: Gonzalo
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Quadri
authors.affiliation: Department of Cardiology,University Hospital of the RWTH Aachen, Aachen, Germany.
authors.forename: Antonio
authors.initials: A
authors.lastname: Colombo
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Biondi-Zoccai
authors.affiliation: Hospital Universitario Clinico San Carlos, Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Escaned
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Moretti
authors.affiliation: Department of Cardiology, Division of Internal Medicine, Città Della Salute e Della Scienza, Turin, Italy.
authors.forename: Fiorenzo
authors.initials: F
authors.lastname: Gaita
mesh_terms: D000328:Adult; D019540:Area Under Curve; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence; D018084:Ultrasonography, Interventional