A prospective study to assess the screening value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) for the identification of patients that benefit from additional cardiac testing prior to vascular surgery.

Patients undergoing major vascular surgery are at significant risk for
perioperative cardiac complications. Although the overall perioperative event
rate has declined over the past 30 years; 30 day cardiovascular mortality
remains as high as 3% to 5%. Myocardial infarction (MI) is the most frequent
fatal complication in this respect, accounting for 10-40% of postoperative
fatalities.
For preoperative cardiac risk stratification scoring of clinical cardiac risk
factors, eg. previous MI, diabetes mellitus, etc., is important. The cardiac
risk can be predicted more accurately by applying cardiac stress tests. However
in patients at low or intermediate risk (0, 1, or 2 clinical cardiac risk
factors) only 14% of these tests are positive. This implies that 86% of the
additional tests does not have any clinical consequences.
In cardiac patients the concentration of a certain bloodmarker (NT-proBNP) is
predictive for future adverse cardiac events. Recent retrospective studies
indicated that NT-proBNP might also predict perioperative cardiac events in
patients undergoing major vascular surgery.

This is a multi-centre prospective study to assess the screening value of
N-terminal pro-B-type natriuretic peptide (NT-proBNP) for the identification of
patients that benefit from additional cardiac testing prior to vascular
surgery.

This is a prospective observational cohort study including 1800 vascular
surgical patients. These patients will be screened for clinical cardiac risk
factors and NT-proBNP levels will be assessed.
In all patients without and those with one or two risk factors NT-proBNP
concentrations are measured. Those with a normal test are referred for surgery
without additional testing. Patients with an abnormal NT-proBNP concentration
will be referred for non-invasive cardiac stress imaging. In all high risk
patients, those with three or more risk factors, NT-proBNP concentrations are
measured and irrespective of the NT-proBNP concentration, routinely all
patients will be referred for additional cardiac stress testing.

In patients with 3 or more clinical cardiac risk factors an extra blood sample
for measurement of NT-proBNP is needed. This extra blood sample is also needed
in patients with 0, 1, or 2 clinical cardiac risk factors. Furthermore, in
these patients (0, 1, or 2 risk factors) an additional cardiac stress test will
be performed in case of an elevated NT-proBNP level. Based on the results of
this test the treating physician might do additional testing and/or therapy.