title: High-risk plaque detected on coronary CT angiography predicts acute coronary syndromes independent of significant stenosis in acute chest pain: results from the ROMICAT-II trial.
abstract: BACKGROUND
  It is not known whether high-risk plaque, as detected by coronary computed tomography angiography (CTA), permits improved early diagnosis of acute coronary syndromes (ACS) independently to the presence of significant coronary artery disease (CAD) in patients with acute chest pain.
  
  
  OBJECTIVE
  The primary aim of this study was to determine whether high-risk plaque features, as detected by CTA in the emergency department (ED), may improve diagnostic certainty of ACS independently and incrementally to the presence of significant CAD and clinical risk assessment in patients with acute chest pain but without objective evidence of myocardial ischemia or myocardial infarction (MI).
  
  
  METHODS
  We included patients randomized to the coronary CTA arm of the ROMICAT-II (Rule Out Myocardial Infarction/Ischemia Using Computer-Assisted Tomography II) trial. Readers assessed coronary CTA qualitatively for the presence of nonobstructive CAD (1% to 49% stenosis), significant CAD (≥50% or ≥70% stenosis), and the presence of at least 1 of the high-risk plaque features (positive remodeling, low <30 Hounsfield units plaque, napkin-ring sign, spotty calcium). In logistic regression analysis, we determined the association of high-risk plaque with ACS (MI or unstable angina pectoris) during the index hospitalization and whether this was independent of significant CAD and clinical risk assessment.
  
  
  RESULTS
  Overall, 37 of 472 patients who underwent coronary CTA with diagnostic image quality (mean age 53.9 ± 8.0 years; 52.8% men) had ACS (7.8%; MI n = 5; unstable angina pectoris n = 32). CAD was present in 262 patients (55.5%; nonobstructive CAD in 217 patients [46.0%] and significant CAD with ≥50% stenosis in 45 patients [9.5%]). High-risk plaques were more frequent in patients with ACS and remained a significant predictor of ACS (odds ratio [OR]: 8.9; 95% CI: 1.8 to 43.3; p = 0.006) after adjustment for ≥50% stenosis (OR: 38.6; 95% CI: 14.2 to 104.7; p < 0.001) and clinical risk assessment (age, sex, number of cardiovascular risk factors). Similar results were observed after adjustment for ≥70% stenosis.
  
  
  CONCLUSIONS
  In patients presenting to the ED with acute chest pain but negative initial electrocardiogram and troponin, presence of high-risk plaques on coronary CTA increased the likelihood of ACS independent of significant CAD and clinical risk assessment (age, sex, and number of cardiovascular risk factors). (Multicenter Study to Rule Out Myocardial Infarction by Cardiac Computed Tomography [ROMICAT-II]; NCT01084239).
authors.affiliation: Department of Radiology and Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria.
authors.forename: Stefan B
authors.initials: SB
authors.lastname: Puchner
authors.affiliation: Department of Radiology and Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Department of Radiology, First Affiliated Hospital of China Medical University, Shenyang, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.affiliation: Department of Radiology and Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Thomas
authors.initials: T
authors.lastname: Mayrhofer
authors.affiliation: Department of Radiology and Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Cardiology Division, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Quynh A
authors.initials: QA
authors.lastname: Truong
authors.affiliation: Cardiology Division, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Hang
authors.initials: H
authors.lastname: Lee
authors.affiliation: Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, Bethesda, Maryland.
authors.forename: Jerome L
authors.initials: JL
authors.lastname: Fleg
authors.affiliation: Department of Emergency Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: John T
authors.initials: JT
authors.lastname: Nagurney
authors.affiliation: Division of Cardiology and the Cardio-Vascular Center, Tufts Medical Center, Boston, Massachusetts.
authors.forename: James E
authors.initials: JE
authors.lastname: Udelson
authors.affiliation: Department of Radiology and Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Cardiology Division, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Udo
authors.initials: U
authors.lastname: Hoffmann
authors.affiliation: Department of Radiology and Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Cardiology Division, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Knight Cardiovascular Institute, Oregon Health & Science University, Portland, Oregon. Electronic address: maros_ferencik@hms.harvard.edu.
authors.forename: Maros
authors.initials: M
authors.lastname: Ferencik
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications / Q000000981:diagnostic imaging*; D059787:Acute Pain / Q000000981:diagnostic imaging* / Q000209:etiology; D002637:Chest Pain / Q000000981:diagnostic imaging* / Q000209:etiology; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000150:complications / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000150:complications / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: acute chest pain; acute coronary syndrome; coronary atherosclerotic plaque; coronary computed tomography