N-terminal pro-B-type natriuretic peptide levels and early outcome after cardiac surgery: a prospective cohort study

Br J Anaesth. 2009 Nov;103(5):647-53. doi: 10.1093/bja/aep234. Epub 2009 Aug 27.

Abstract

Background: N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a powerful predictor of cardiovascular outcome in many circumstances. There are, however, limited data regarding the utility of NT-proBNP or BNP levels in patients undergoing cardiac surgery. The current study assesses the ability of NT-proBNP to predict early outcome in this setting.

Methods: One thousand and ten patients undergoing non-emergent cardiac surgery were recruited prospectively. Baseline clinical details were obtained and the European System for Cardiac Operative Risk Evaluation (EuroSCORE) and Parsonnet score were calculated. Preoperative NT-proBNP levels were measured using the Roche Elecsys assay. The primary endpoint was 30 day mortality.

Results: Median NT-proBNP levels were 624 ng litre(-1) among patients who died within 30 days of surgery (n=29), compared with 279 ng litre(-1) in survivors [odds ratio (OR) 1.03 per 250 ng litre(-1), 95% confidence interval 1.01-1.05, P=0.001). NT-proBNP levels remained predictors of 30 day mortality in models including either the additive EuroSCORE (OR 1.03 per 250 ng litre(-1), P=0.01), the logistic EuroSCORE (OR 1.03 per 250 ng litre(-1), P=0.004), or the Parsonnet score (OR 1.02 per 250 ng litre(-1), P=0.04). Levels of NT-proBNP were also predictors of prolonged (>1 day) stay in the intensive care unit (OR 1.03 per 250 ng litre(-1), P<0.001) and of a hospital stay >1 week (OR 1.07 per 250 ng litre(-1), P<0.001). They remained predictive of these outcomes in regression models that included either the EuroSCORE or the Parsonnet score and in a model that included all study variables.

Conclusions: NT-proBNP levels predict early outcome after cardiac surgery. Their prognostic utility is modest-but is independent of traditional indicators and conventional risk prediction scores.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Biomarkers / blood
  • Cardiac Surgical Procedures* / mortality
  • Coronary Artery Bypass
  • Epidemiologic Methods
  • Female
  • Humans
  • Intensive Care Units / statistics & numerical data
  • Length of Stay / statistics & numerical data
  • Male
  • Middle Aged
  • Natriuretic Peptide, Brain / blood*
  • Peptide Fragments / blood*
  • Preoperative Care / methods
  • Prognosis
  • Scotland / epidemiology
  • Treatment Outcome

Substances

  • Biomarkers
  • Peptide Fragments
  • pro-brain natriuretic peptide (1-76)
  • Natriuretic Peptide, Brain