title: Are biomarkers additive to pulmonary embolism severity index for severity assessment in normotensive patients with acute pulmonary embolism?
abstract: BACKGROUND
  Biomarkers and clinical prediction rules have been proposed for severity assessment in acute pulmonary embolism (PE).
  
  
  OBJECTIVE
  The aim of this study was to compare biomarkers with the PE Severity Index (PESI), a validated scoring system for predicting 30-day mortality and to determine if addition of biomarkers to PESI would improve its predictive accuracy.
  
  
  METHODS
  We conducted a retrospective analysis of normotensive patients admitted with PE confirmed by CT pulmonary angiogram, to three teaching hospitals between January 2005 and July 2007. All patients had admission levels of D-dimer and Troponin I and calculation of PESI score on admission. The outcome of interest was 30-day mortality.
  
  
  RESULTS
  There were 411 patients included in the study. Patients who died had higher levels of D-dimer (median 2947 ng/ml vs. 1464 ng/ml; P=0.02), Troponin (57.1% positive vs. 13.8%; P<0.0001) and higher PESI scores [median 109 vs. 83; P<0.0001], compared to survivors. PESI had superior accuracy for predicting 30-day mortality than a combination of Troponin and D-dimer (AUC 0.80 vs. 0.75). Addition of Troponin to PESI further improved the predictive value of the score (AUC 0.85 for vs. AUC 0.80 for PESI alone).
  
  
  CONCLUSIONS
  Biomarkers and clinical prediction rules predict outcome in acute PE. Addition of troponin to the PESI scoring system improves the predictive value for 30-day mortality and may be useful for guiding initial management of patients presenting with PE.
authors.affiliation: Department of Respiratory Medicine, Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh, EH16 4SA, UK. aransinga@gmail.com
authors.forename: A
authors.initials: A
authors.lastname: Singanayagam
authors.forename: C
authors.initials: C
authors.lastname: Scally
authors.forename: M Z
authors.initials: MZ
authors.lastname: Al-Khairalla
authors.forename: L
authors.initials: L
authors.lastname: Leitch
authors.forename: L E
authors.initials: LE
authors.lastname: Hill
authors.forename: J D
authors.initials: JD
authors.lastname: Chalmers
authors.forename: A T
authors.initials: AT
authors.lastname: Hill
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D004812:Epidemiologic Methods; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D012606:Scotland / Q000453:epidemiology; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D019210:Troponin I / Q000097:blood
chemical_list: D015415:Biomarkers; D005338:Fibrin Fibrinogen Degradation Products; D019210:Troponin I; C036309:fibrin fragment D