Abstract 10165: Prognostic Value of Serial NT-proBNP Testing in Patients with Acute Myocardial Infarction
Background: Brain natriuretic peptides (BNP) are important predictors of outcomes in patients (pts) with acute MI. The predictive power of values measured after discharge is less clear.
Methods: We measured NT-proBNP at enrollment and 1 month after discharge in a biomarker substudy from TRIUMPHANT, a prospective MI registry. Outcomes included 2-year mortality and 1-year readmission, along with follow-up Dyspnea scores (range 0-3, higher scores=more dyspnea) assessed at 6 months. An elevated NT-proBNP was defined using age-specific criteria: ≤50, 450 pg/ml; 50-75, 900 pg/ml; >75, 1800 pg/ml. Pts were classified into 4 groups (Low/Low (referent group), Low/High, High/Low, High/High) based on NT-proBNP value at enrollment and 1 month. The incremental predictive value of NT-proBNP was determined after adjusting for clinical variables (6-month GRACE risk score, diabetes and EF<40%) using proportional hazards and linear regression models that also adjusted for site.
Results: Of the 803 pts included, 303 (38%) were Low/Low, 240 (30%), were High/High, 230 (29%) were High/Low, and 30 (3.7%) were Low/High (excluded from further analysis due to low numbers). High/High pts more often had diabetes (36% High/High vs 24% each for Low/Low and High/Low, respectively), heart failure (13% vs 2% and 5.7%), prior MI (25% vs 19% and 17%), EF<40% (30% vs 4.3% and 17%) and higher GRACE Scores (104±28 vs 92±24 and 98±28). In the adjusted models, 2-year mortality was highest in High/High pts (Figure). In contrast, mortality was similar in the High/Low pts. Six-month Dyspnea scores were significantly correlated with NT-proBNP category. Hospital readmission was significantly more likely in the High/High vs the High/Low group but not the Low/Low group.
Conclusions: Elevated NT-proBNP at 1 month post-discharge was associated with a higher risk of mortality, hospitalization and dyspnea among AMI pts. NT-proBNP measurement after discharge may lead to improved identification of high-risk pts.
- © 2011 by American Heart Association, Inc.