Plasma N-terminal B type natriuretic peptide as an Indicator of Long-term Survival After Acute Myocardial Infarction : Comparison With Plasma Mid-regional Pro-atrial Natriuretic Peptide-Leicester Acute Myocardial Infarction Peptide ( LAMP ) Study

word count 208) Objectives Our aim was to assess the prognostic value of MR-proANP in patients post acute myocardial infarction (AMI). Background Multimarker strategies may assist risk stratification post-AMI. Midregional Pro-Atrial Natriuretic Peptide (MR-proANP) is a newly described stable fragment of N-terminal Pro-Atrial Natriuretic Peptide. We compared the prognostic value of MR-proANP and an established marker N-terminal pro-B-type natriuretic peptide (NT-proBNP) post-AMI. Methods We recruited 983 consecutive post-AMI patients (720 men, median [range] age 65[24-95] years) in a prospective study with follow-up over 343[0-764] days. Results Plasma MR-proANP was raised in patients who died (n=101) compared to survivors (median [range] pmol/L, 310[48-1150] vs. 108[4.9-1210], P<0.0001). Using Cox modelling log10MRproANP (HR 3.87) and log10NT-proBNP (HR 3.25) were significant independent predictors of death. In patients stratified by NT-proBNP in the highest quartile (> ~5900 pmol/L), MRproANP in the top quartile (~330 pmol/L) was associated with poorer outcome (P<0.0001). Findings were similar for heart failure as an individual endpoint. However neither marker predicted recurrent AMI. Conclusions The A and B-type natriuretic systems are activated post AMI. MR-proANP is a powerful predictor of adverse outcome especially in those with an elevated NT-proBNP. MR-proANP may represent a clinically useful marker of prognosis after an AMI as part of a multimarker strategy targeting the natriuretic neurohormonal pathway.