title: Histopathologic characteristics of atherosclerotic coronary disease and implications of the findings for the invasive and noninvasive detection of vulnerable plaques.
abstract: OBJECTIVE
  The goal of this study was to identify histomorphologic characteristics of atherosclerotic plaques and to determine the amenability of some of these components to be used as markers for invasive and noninvasive imaging.
  
  
  BACKGROUND
  Rupture of the atherosclerotic plaques is responsible for the majority of acute coronary events, and the culprit lesions demonstrate distinct histopathologic features. It has been tacitly believed that plaque rupture (PR) is associated with angiographically minimally occlusive lesions.
  
  
  METHODS
  We obtained 295 coronary atherosclerotic plaques, including stable (fibroatheroma [FA]; n = 105), vulnerable (thin-cap fibroatheroma [TCFA]; n = 88), and disrupted plaques (plaque rupture [PR]; n = 102) from the hearts of 181 men and 32 women who had died suddenly. The hierarchical importance of fibrous cap thickness, percent luminal stenosis, macrophage area, necrotic core area, and calcified plaque area was evaluated by using recursive partitioning analysis. Because clinical assessment of fibrous cap thickness is not possible by noninvasive imaging, it was excluded from the second set of partitioning analysis.
  
  
  RESULTS
  Thickness of the fibrous cap emerged as the best discriminator of plaque type; the cap thickness measured <55 μm in ruptured plaques, and all FA were associated with >84-μm cap thickness. Although the majority of TCFA were found in the 54- to 84-μm thickness group, those with <54-μm thickness were more likely to show <74% luminal stenosis (area under the curve: FA, 1.0; TCFA, 0.89; PR, 0.90). After exclusion of cap thickness, analysis of the plaque characteristics revealed macrophage infiltration and necrotic core to be the 2 best discriminators of plaque types (area under the curve: FA, 0.82; TCFA, 0.58; PR, 0.72). More than 75% cross-section area stenosis was seen in 70% of PR and 40% of TCFA; only 5% PR and 10% TCFA were <50% narrowed.
  
  
  CONCLUSIONS
  This postmortem study defines histomorphologic characteristics of vulnerable plaques, which may help develop imaging strategies for identification of such plaques in patients at a high risk of sustaining acute coronary events.
authors.affiliation: Mount Sinai School of Medicine, New York, New York 10029, USA. narula@mountsinai.org
authors.forename: Jagat
authors.initials: J
authors.lastname: Narula
authors.forename: Masataka
authors.initials: M
authors.lastname: Nakano
authors.forename: Renu
authors.initials: R
authors.lastname: Virmani
authors.forename: Frank D
authors.initials: FD
authors.lastname: Kolodgie
authors.forename: Rita
authors.initials: R
authors.lastname: Petersen
authors.forename: Robert
authors.initials: R
authors.lastname: Newcomb
authors.forename: Shaista
authors.initials: S
authors.lastname: Malik
authors.forename: Valentin
authors.initials: V
authors.lastname: Fuster
authors.forename: Aloke V
authors.initials: AV
authors.lastname: Finn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003324:Coronary Artery Disease / Q000473:pathology*; D023921:Coronary Stenosis / Q000473:pathology; D003331:Coronary Vessels / Q000473:pathology*; D005260:Female; D005355:Fibrosis; D006801:Humans; D007249:Inflammation / Q000473:pathology; D008264:Macrophages / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D009336:Necrosis; D058226:Plaque, Atherosclerotic / Q000473:pathology*; D012720:Severity of Illness Index