Midregional pro-atrial natriuretic peptide is a useful indicator for the detection of impaired left ventricular function in patients with coronary artery disease.
OBJECTIVE
We compared the diagnostic performance of N-terminal pro-brain natriuretic peptide (NT-proBNP) with a newly developed assay for the midregional part of pro-atrial natriuretic peptide (MR-proANP) concerning the detection of impaired left ventricular ejection function (LVEF) among patients with coronary artery disease (CAD).


RESULTS
Plasma levels of MR-proANP and NT-proBNP were determined in 102 consecutive patients with a history of ST-elevation myocardial infarction. Plasma levels of both markers were measured during a mean follow-up period of 687 days after acute myocardial infarction. Univariate analyses revealed inverse correlations between MR-proANP levels and LVEF (r=-0.39; p<0.001), NT-proBNP levels and LVEF (r=-0.39; p<0.001) and a positive correlation between MR-proANP and NT-proBNP (r=0.75; p<0.001). After adjustment for traditional risk factors, MR-proANP was the strongest predictor for LVEF (p=0.001) in multivariate analysis, being even superior to NT-proBNP. The area under the ROC curve (AUC) indicated moderate performance (AUC=0.73; p<0.01) of MR-proANP regarding the detection of a reduced LVEF<50%. The AUC of NT-proBNP for detection of impaired LVEF<50% was 0.68 (p=0.019). The negative predictive values of both markers were 86% for MR-proANP at a cut-off >135 pmol/L and NT-proBNP at a cut-off >560 pmol/L. At these cut-offs, the specificity of MR-proANP was 90%, and the specificity of NT-proBNP was 84%.


CONCLUSIONS
MR-proANP is a useful indicator for the exclusion of a preserved left ventricular function in patients with coronary artery disease. The study demonstrates that the diagnostic performance of MR-proANP is comparable to the "gold standard" NT-proBNP.
Elmas
Elif
E
1st Department of Medicine, Medical Faculty Mannheim of the University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany. elif.elmas@med.ma.uni-heidelberg.de
Brueckmann
Martina
M
Lang
Siegfried
S
Kälsch
Thorsten
T
Haghi
Dariush
D
Sueselbeck
Tim
T
Dempfle
Carl Erik
CE
Borggrefe
Martin
M
D009320:Atrial Natriuretic Factor / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D003327:Coronary Disease / Q000097:blood*; D004452:Echocardiography; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000097:blood / Q000175:diagnosis*
D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor