title: Coronary calcium significantly affects quantitative analysis of coronary ultrasound: importance for atherosclerosis progression/regression studies.
abstract: BACKGROUND
  Coronary atherosclerosis is a dynamic process, which progresses differently in coronary segments containing noncalcified or calcified plaques. This may have implications for the study of the effects of therapy on progression/regression.
  
  
  OBJECTIVE
  To test this hypothesis, we performed a post-hoc analysis on data of a randomized trial in which perindopril treatment was compared with placebo on progression/regression of atherosclerosis with regard to the degree of calcification.
  
  
  RESULTS
  The intracoronary ultrasound data of 118 patients, who were enrolled in the multicentre, double-blinded randomized trial (PERSPECTIVE), were analysed. Vessel, lumen and plaque areas were measured in 711 5-mm-long matched coronary segments (perindopril 360, placebo 351). Each individual intracoronary ultrasound cross-section was binary labelled for the presence of calcium (yes/no), and the degree of calcium was assessed as a percentage of length. The segments were classified into three groups: 0-25, 25-50 and 50-100% (percentage of length) calcification. Coronary plaques with no or little calcium (0-25%) regressed on perindopril and did not change on placebo (-0.33+/-1.74 vs. -0.03+/-1.66, respectively; P = 0.04). Plaques containing moderate calcium (group 25-50%) did not change and plaques with severe amounts of calcification (group 50-100%) equally progressed.
  
  
  CONCLUSIONS
  Noncalcified plaques may be amenable to regression with ACE inhibitor treatment. The method, which considers the amount of calcium content in a plaque, may lead to new insights for quantitative analysis of the effects of therapy in progression/regression studies of atherosclerosis.
authors.affiliation: Thoraxcenter, Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands. n.Bruining@erasmusmc.nl
authors.forename: Nico
authors.initials: N
authors.lastname: Bruining
authors.forename: Sebastiaan
authors.initials: S
authors.lastname: de Winter
authors.forename: Jos R T C
authors.initials: JR
authors.lastname: Roelandt
authors.forename: Gastón A
authors.initials: GA
authors.lastname: Rodriguez-Granillo
authors.forename: Iddo
authors.initials: I
authors.lastname: Heller
authors.forename: Ron T
authors.initials: RT
authors.lastname: van Domburg
authors.forename: Ronald
authors.initials: R
authors.lastname: Hamers
authors.forename: Pim J
authors.initials: PJ
authors.lastname: de Feijter
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D002114:Calcinosis / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D020913:Perindopril / Q000627:therapeutic use*; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D020913:Perindopril