title: Intravascular ultrasound assessment of remodelling and reference segment plaque burden in type-2 diabetic patients.
abstract: OBJECTIVE
  Intravascular ultrasound (IVUS) assesses arterial remodelling by comparing the lesion external elastic membrane (EEM) with the reference segments; however, reference segments are rarely disease-free. The aim was to assess lesion and reference segment remodelling and plaque burden in patients with type-2 diabetes mellitus.
  
  
  RESULTS
  We used pre-intervention IVUS to study 62 de novo lesions in 43 patients with type-2 diabetes mellitus. The lesion site was the image slice with the smallest lumen cross-sectional area (CSA). The proximal and distal reference segments were the most normal-looking segments within 5 mm proximal and distal to the lesion. Plaque burden was measured as plaque CSA/EEM CSA. The remodelling index was defined as lesion EEM CSA/mean reference EEM CSA. Reference segment plaque burden measured 0.54 +/- 0.09. The majority of lesions (83.9%) had negative remodelling (lesion EEM < reference). Similarly, the slope of the regression line relating EEM to plaque CSA within the lesion was less than the reference substantiating negative remodelling. The reference segment plaque burden correlated inversely with the difference between IVUS lumen and quantitative coronary angiographic artery size [slope = -0.12 (95% CI -0.17 to -0.07); P < 0.001] in all patients with type-2 diabetes mellitus.
  
  
  CONCLUSIONS
  Lesions in type-2 diabetic patients are different from previous reports in non-diabetics. Lesions in type-2 diabetics are characterized by a large reference segment plaque burden and negative lesion site remodelling. These IVUS findings may explain the angiographic appearance of small arteries in diabetic patients.
authors.affiliation: Catheterization Laboratory, Department of Cardiology, Odense University Hospital, Odense C, Denmark. okkels@dadlnet.dk
authors.forename: Lisette Okkels
authors.initials: LO
authors.lastname: Jensen
authors.forename: Per
authors.initials: P
authors.lastname: Thayssen
authors.forename: Gary S
authors.initials: GS
authors.lastname: Mintz
authors.forename: Michael
authors.initials: M
authors.lastname: Maeng
authors.forename: Anders
authors.initials: A
authors.lastname: Junker
authors.forename: Anders
authors.initials: A
authors.lastname: Galloe
authors.forename: Evald Hoej
authors.initials: EH
authors.lastname: Christiansen
authors.forename: Soeren K S
authors.initials: SK
authors.lastname: Hoffmann
authors.forename: Knud Erik
authors.initials: KE
authors.lastname: Pedersen
authors.forename: Henrik Steen
authors.initials: HS
authors.lastname: Hansen
authors.forename: Knud Noerregaard
authors.initials: KN
authors.lastname: Hansen
mesh_terms: D000368:Aged; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000473:pathology; D003924:Diabetes Mellitus, Type 2 / Q000000981:diagnostic imaging* / Q000473:pathology; D003925:Diabetic Angiopathies / Q000000981:diagnostic imaging* / Q000473:pathology; D019160:Endosonography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D018084:Ultrasonography, Interventional / Q000379:methods