Use of B-type natriuretic peptide as a prognostic indicator in acute coronary syndromes

Abstract

The present invention relates to materials and procedures for evaluating the prognosis of patients suffering from acute coronary syndromes. In particular, the level of BNP, or a marker related to BNP, in a patient sample, alone or in combination with one or more other prognostic markers, provides prognostic information useful for predicting near-term morbidity and/or mortality across the entire spectrum of acute coronary syndromes, including unstable angina, non-ST-elevation non-Q wave myocardial infarction, ST-elevation non-Q wave MI, and transmural (Q-wave) MI.

We claim:  
     
         1 . A method of determining a prognosis of a patient diagnosed with a non-ST-elevation acute coronary syndrome, the method comprising: 
 determining a level of a polypeptide originating from pre-pro B-type natriuretic peptide in a sample obtained from said patient; and    correlating said polypeptide level to said patient prognosis by determining if said polypeptide level is associated with a predisposition to an adverse outcome of said non-ST-elevation acute coronary syndrome.    
     
     
         2 . A method according to  claim 1 , wherein said polypeptide originating from the pre-pro B-type natriuretic peptide (BNP) molecule is B-type natriuretic peptide (BNP); and 
 said correlating step comprises correlating said BNP level to said patient prognosis by determining if said BNP level is associated with a predisposition to an adverse outcome of said non-ST-elevation acute coronary syndrome.    
     
     
         3 . A method according to  claim 2 , wherein said adverse outcome is selected from the group consisting of death, myocardial infarction, and congestive heart failure.  
     
     
         4 . A method according to  claim 2 , wherein said correlating step comprises comparing said BNP level to a threshold BNP level, whereby, when said BNP level exceeds said threshold BNP level, said patient is predisposed to said adverse outcome.  
     
     
         5 . A method according to  claim 4 , wherein said threshold BNP level is at least about 80 pg/mL.  
     
     
         6 . A method according to  claim 2 , wherein said sample is selected from the group consisting of a blood sample, a serum sample, and a plasma sample.  
     
     
         7 . A method according to  claim 2 , further comprising correlating said BNP level with one or more additional prognostic markers associated with said patient, whereby the combination of said BNP level with said additional prognostic marker(s) increases the predictive value of said BNP or related marker level for said adverse outcome.  
     
     
         8 . A method according to  claim 7 , wherein one of said prognostic marker(s) is a cardiac-specific troponin isoform concentration in a sample obtained from said patient.  
     
     
         9 . A method according to  claim 2 , further comprising determining a level of cardiac-specific troponin I in a sample obtained from said patient, and correlating both said BNP level and said cardiac-specific troponin I level to said patient prognosis, whereby the combination of said BNP level with said cardiac-specific troponin I level increases the predictive value of said BNP level for said adverse outcome.  
     
     
         10 . A method according to  claim 1 , wherein said polypeptide originating from the pre-pro B-type natriuretic peptide (BNP) molecule is a marker related to BNP; and 
 said correlating step comprises correlating said BNP-related marker level to said patient prognosis by determining if said BNP-related marker level is associated with a predisposition to an adverse outcome of said non-ST-elevation acute coronary syndrome.    
     
     
         11 . A method according to  claim 10 , wherein said adverse outcome is selected from the group consisting of death, myocardial infarction, and congestive heart failure.  
     
     
         12 . A method according to  claim 10 , wherein said correlating step comprises comparing said BNP-related marker level to a threshold BNP-related marker level, whereby, when said BNP-related marker level exceeds said threshold BNP-related marker level, said patient is predisposed to said adverse outcome.  
     
     
         13 . A method according to  claim 12 , wherein said threshold BNP-related marker level is at least about 80 pg/mL.  
     
     
         14 . A method according to  claim 10 , wherein said sample is selected from the group consisting of a blood sample, a serum sample, and a plasma sample.  
     
     
         15 . A method according to  claim 10 , further comprising correlating said BNP-related marker level with one or more additional prognostic markers associated with said patient, whereby the combination of said BNP-related marker level with said additional prognostic marker(s) increases the predictive value of said BNP-related marker or related marker level for said adverse outcome.  
     
     
         16 . A method according to  claim 15 , wherein one of said prognostic marker(s) is a cardiac-specific troponin isoform concentration in a sample obtained from said patient.  
     
     
         17 . A method according to  claim 10 , further comprising determining a level of cardiac-specific troponin I in a sample obtained from said patient, and correlating both said BNP-related marker level and said cardiac-specific troponin I level to said patient prognosis, whereby the combination of said BNP-related marker level with said cardiac-specific troponin I level increases the predictive value of said BNP-related marker level for said adverse outcome.  
     
     
         18 . A method according to any one of claims  10 - 17 , wherein said BNP-related marker is NT pro-BNP.