N-terminal pro-brain natriuretic peptide and angiotensin-converting enzyme-2 levels and their association with postoperative cardiac complications after emergency orthopedic surgery

Am J Cardiol. 2012 May 1;109(9):1365-73. doi: 10.1016/j.amjcard.2011.12.032. Epub 2012 Feb 28.


The prognostic usefulness of the cardiac biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP) and angiotensin-converting enzyme 2 (ACE-2), in predicting adverse cardiac outcomes after orthopedic surgery is not well studied. The aim of our study was to determine the usefulness of perioperative NT-proBNP and ACE-2 for predicting cardiac events after emergency orthopedic surgery. The perioperative NT-proBNP and ACE-2 levels were determined in 187 consecutive patients aged >60 years who underwent orthopedic surgery with 1 year of follow-up for any cardiac complications (defined as acute myocardial infarction, congestive cardiac failure, atrial fibrillation, or major arrhythmia) and death. Of the 187 patients, 20 (10.7%) sustained an in-hospital postoperative cardiac complication. The total all-cause in-hospital and 1-year mortality rate was 1.6% (3 of 187) and 8.6% (16 of 187), respectively. The median preoperative and postoperative NT-proBNP level was greater in patients who sustained an in-hospital cardiac event than in those who had not (386 vs 2,273 pg/ml, p <0.001, and 605 vs 4,316 pg/ml, p <0.001, respectively). Similarly, the postoperative median ACE-2 levels were significantly greater in the patients with an in-hospital cardiac event than in those without (25.3 vs 39.5 pmol/ml/min, p = 0.012). A preoperative NT-proBNP level of ≥741 pg/ml (odds ratio 4.5, 95% confidence interval 1.3 to 15.2, p = 0.017), postoperative troponin elevation (odds ratio 4.9, 95% confidence interval 1.3 to 18.9, p = 0.022), and number of co-morbidities (odds ratio 1.8, 95% confidence interval 1.2 to 2.8, p = 0.009) independently predicted in-hospital cardiac complications on multivariate analysis. The pre- and postoperative NT-proBNP level independently predicted 1-year cardiovascular complications but not the ACE-2 levels. In conclusion, elevated perioperative NT-proBNP predicted in-hospital and 1-year cardiac events in an emergency orthopedic population but the ACE-2 levels did not, which requires additional study for validation.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Biomarkers / blood
  • Female
  • Follow-Up Studies
  • Heart Diseases / blood
  • Heart Diseases / diagnosis*
  • Heart Diseases / etiology
  • Humans
  • Male
  • Middle Aged
  • Natriuretic Peptide, Brain / blood*
  • Orthopedic Procedures / adverse effects*
  • Peptide Fragments / blood*
  • Peptidyl-Dipeptidase A / blood*
  • Postoperative Complications*
  • Postoperative Period
  • Predictive Value of Tests
  • Prognosis
  • Protein Precursors
  • Retrospective Studies


  • Biomarkers
  • Peptide Fragments
  • Protein Precursors
  • pro-brain natriuretic peptide (1-76)
  • Natriuretic Peptide, Brain
  • Peptidyl-Dipeptidase A
  • angiotensin converting enzyme 2