title: N-terminal pro-brain natriuretic peptide or troponin testing followed by echocardiography for risk stratification of acute pulmonary embolism.
abstract: BACKGROUND
  Brain natriuretic peptide (BNP) and N-terminal (NT)-proBNP have recently emerged as promising parameters for risk assessment in acute pulmonary embolism (PE). However, their positive predictive value is low, and the prognostic implications of NT-proBNP or troponin elevation alone are questionable.
  
  
  RESULTS
  To determine whether the combination of NT-proBNP testing with echocardiography may identify both low-risk and high-risk patients with PE, we examined 124 consecutive patients with proved PE. All underwent echocardiography on admission to detect right ventricular dysfunction. NT-proBNP and troponin concentrations were measured in one core laboratory. The primary end point was death or major in-hospital complications. The cutoff level of 1000 pg/mL had a high negative predictive value (95% for a complicated course, 100% for death), but NT-proBNP > or =1000 pg/mL did not independently predict an adverse outcome. Combination of NT-proBNP testing with echocardiography identified 3 major risk groups. A positive echocardiogram was associated with a 12-fold elevation in complication risk compared with patients with low NT-proBNP (P=0.002), whereas NT-proBNP elevation without right ventricular dysfunction on echocardiography only slightly increased the risk of an adverse outcome (P=0.17). The combination of cardiac troponin testing with echocardiography yielded similar complication rates in the lowest-risk group and a similar magnitude of risk elevation for the highest-risk patients, but it also increased the number of intermediate-risk groups.
  
  
  CONCLUSIONS
  Our results support a simple risk stratification algorithm for patients with PE, with the use of NT-proBNP or troponin testing as an initial step that should be followed by echocardiography if elevated levels of the biomarker are found.
authors.affiliation: Department of Clinical Chemistry, Georg August University of Goettingen, D-37099 Goettingen, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Binder
authors.forename: Burkert
authors.initials: B
authors.lastname: Pieske
authors.forename: Manfred
authors.initials: M
authors.lastname: Olschewski
authors.forename: Annette
authors.initials: A
authors.lastname: Geibel
authors.forename: Beate
authors.initials: B
authors.lastname: Klostermann
authors.forename: Christian
authors.initials: C
authors.lastname: Reiner
authors.forename: Stavros
authors.initials: S
authors.lastname: Konstantinides
mesh_terms: D000208:Acute Disease; D000368:Aged; D000465:Algorithms; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D009994:Osmolar Concentration; D010446:Peptide Fragments / Q000097:blood*; D011655:Pulmonary Embolism / Q000150:complications / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology*; D018570:Risk Assessment / Q000379:methods / Q000592:standards; D014336:Troponin / Q000097:blood*
chemical_list: D010446:Peptide Fragments; D014336:Troponin; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain