Evaluation of B-type natriuretic peptide for risk assessment in unstable angina/non-ST-elevation myocardial infarction: B-type natriuretic peptide and prognosis in TACTICS-TIMI 18.
OBJECTIVE
This study was designed to evaluate B-type natriuretic peptide (BNP) for risk assessment and clinical decision making over a range of cut points, alone and with cardiac troponin I (cTnI), in patients with non-ST-elevation acute coronary syndromes (ACS).


BACKGROUND
B-type natriuretic peptide holds promise for risk stratification. Additional evidence regarding optimal decision limits, use in combination with troponin, and use in targeting therapy is needed before acceptance into clinical use for ACS.


METHODS
We evaluated BNP at baseline in 1,676 patients with non-ST-elevation ACS randomized to early invasive versus conservative management.


RESULTS
Patients with elevated BNP (>80 pg/ml; n = 320) were at higher risk of death at seven days (2.5% vs. 0.7%, p = 0.006) and six months (8.4% vs. 1.8%, p < 0.0001). The association between BNP and mortality at six months (adjusted odds ratio [OR] 3.3; 95% confidence interval [CI] 1.7 to 6.3) was independent of important clinical predictors, including cTnI and congestive heart failure (CHF). Patients with elevated BNP had a fivefold higher risk of developing new CHF by 30 days (5.9% vs. 1.0%, p < 0.0001). B-type natriuretic peptide added prognostic information to cTnI, discriminating patients at higher mortality risk among those with negative (OR 6.9; 95% CI 1.9 to 25.8) and positive (OR 4.1; 95% CI 1.9 to 9.0) baseline cTnI results. No difference was observed in the effect of invasive versus conservative management when stratified by baseline levels of BNP (p(interaction) > or = 0.6).


CONCLUSIONS
Elevated BNP (>80 pg/ml) at presentation identifies patients with non-ST-elevation ACS who are at higher risk of death and CHF and adds incremental information to cTnI. Additional work is needed to identify therapies that may reduce the risk associated with increased BNP.
Morrow
David A
DA
Cardiovascular Division, Department of Medicine, Brigham & Women's Hospital, Boston, Massachusetts 02115, USA. dmorrow@partners.org
de Lemos
James A
JA
Sabatine
Marc S
MS
Murphy
Sabina A
SA
Demopoulos
Laura A
LA
DiBattiste
Peter M
PM
McCabe
Carolyn H
CH
Gibson
C Michael
CM
Cannon
Christopher P
CP
Braunwald
Eugene
E
D000328:Adult; D000368:Aged; D000789:Angina, Unstable / Q000097:blood* / Q000503:physiopathology / Q000628:therapy; D009320:Atrial Natriuretic Factor / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002316:Cardiotonic Agents / Q000097:blood*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000503:physiopathology / Q000628:therapy; D020097:Natriuretic Peptide, Brain; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic; D012107:Research Design; D018570:Risk Assessment
D015415:Biomarkers; D002316:Cardiotonic Agents; D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor