title: Baseline natriuretic peptide levels in relation to myocardial ischemia, troponin T release and heart rate variability in patients undergoing major vascular surgery.
abstract: BACKGROUND
  This study was conducted to determine the association between baseline N-terminal pro-B-type natriuretic peptide (NT-proBNP) and myocardial ischemia, troponin T release and heart rate variability (HRV) in patients undergoing major vascular surgery.
  
  
  METHODS
  In a prospective study, 182 vascular surgery patients were evaluated by clinical risk factors, dobutamine stress echocardiography and baseline NT-proBNP levels. Myocardial ischemia was detected by continuous 12-lead electrocardiographic monitoring starting 1 day before to 2 days after surgery. Troponin T (>0.03 ng/ml) was measured on day 1, 3 and 7 postoperatively and before discharge. HRV was measured at the day prior to surgery.
  
  
  RESULTS
  The median NT-proBNP level was 184 ng/l (interquartile range: 79-483 ng/l). Myocardial ischemia was detected in 21% and troponin T release in 17% of patients. After adjustment for clinical risk factors and stress echocardiography results, higher NT-proBNP levels (per 1 ng/l increase in the natural logarithm of NT-proBNP) were associated with a higher incidence of myocardial ischemia (odds ratio: 1.59, 95% confidence interval: 1.21-2.08, P<0.001) and troponin T release (odds ratio: 1.76, 95% confidence interval: 1.33-2.34, P<0.001). The optimal cutoff value of NT-proBNP to predict ischemia and/or troponin T release was 270 ng/l (area under the curve: 0.70). Higher baseline NT-proBNP levels were also associated with a larger ischemic burden at electrocardiographic monitoring (r=0.22, P=0.03). No significant correlation, however, was found between NT-proBNP and preoperative HRV (r=-0.024, P=0.78).
  
  
  CONCLUSIONS
  Elevated baseline NT-proBNP levels are significantly associated with perioperative myocardial ischemia and troponin T release, but not with preoperative HRV in patients undergoing major vascular surgery.
authors.affiliation: Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Harm H
authors.initials: HH
authors.lastname: Feringa
authors.forename: Radosav
authors.initials: R
authors.lastname: Vidakovic
authors.forename: Stefanos E
authors.initials: SE
authors.lastname: Karagiannis
authors.forename: Robert
authors.initials: R
authors.lastname: de Jonge
authors.forename: Jan
authors.initials: J
authors.lastname: Lindemans
authors.forename: Dustin
authors.initials: D
authors.lastname: Goei
authors.forename: Olaf
authors.initials: O
authors.lastname: Schouten
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: Bax
authors.forename: Don
authors.initials: D
authors.lastname: Poldermans
mesh_terms: D004280:Dobutamine / Q000008:administration & dosage; D004452:Echocardiography; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D017202:Myocardial Ischemia / Q000097:blood* / Q000503:physiopathology; D045265:Natriuretic Peptides / Q000097:blood*; D011446:Prospective Studies; D020107:Troponin T / Q000097:blood*; D014656:Vascular Surgical Procedures
chemical_list: D045265:Natriuretic Peptides; D020107:Troponin T; D004280:Dobutamine