Background: Risk stratification is important in patients with unstable coronary artery disease (CAD), i.e. unstable angina or non-ST-elevation myocardial infarction. This article focuses on the emerging role of N-terminal pro brain natriuretic peptide (NT-proBNP) and the results from the FAST, GUSTO IV and FRISC II trials.
Methods: In the FAST study, NT-proBNP was measured on admission in 755 patients admitted because of symptoms suggestive of unstable CAD. Follow up was performed after 40 months. The GUSTO IV and the FRISC II-trials included patients with unstable CAD and NT-proBNP was analyzed in 6806 and 2019 patients, with follow up after 1 and 2 years, respectively.
Results: In the FAST study, patients in the 2nd, 3rd, and 4th NT-proBNP quartile had a relative risk of subsequent death of 4.2 (1.6-11.1), 10.7 (4.2-26.8) and 26.6 (10.8-65.5), respectively. In the GUSTO IV trial, increasing quartiles of NT-proBNP were related to short and long term mortality which at 1 year was; 1.8%, 3.9%, 7.7% and 19.2% (P<0.001), respectively. In multivariable analyses including well-known predictors of outcome, NT-proBNP level was independently associated to mortality in all three studies. In the FRISC II trial, the NT-proBNP level, especially if combined with a marker of inflammation, identified those with the greatest benefit from an early invasive strategy.
Conclusion: NT-proBNP is strongly associated with mortality in patients with suspected or confirmed unstable CAD and, combined with a marker of inflammation, seems helpful in identifying those with greatest benefit from an early invasive strategy.