OBJECTIVETo elucidate whether the plasma concentration of NT-proBNP in patients with acute coronary syndrome (ACS) correlated with severity of the diseases and whether NT-proBNP is a reliable biochemical marker correctly indicates the severity of ACS.

METHODSEighty-nine subjects came from CCU of Cardiology Department of People's Hospital Beijing University from October 2003 to June 2004 and aged 34-85 y (66.89 +/- 11.12 y). In this study the spectrum of ACS only included unstable angina pectoris (UA) and acute myocardial infarction (AMI). Patients with UA were separated into 3 groups by Braunwald classes and those with AMI were separated into 4 groups by Killip classes when their venous blood samples were collected. Plasma concentration of NT-proBNP was measured by enzyme linked immunoabsorbent assay. Data was estimated by SPSS.

RESULTSThe concentration of NT-proBNP in patients with ACS was dramatically correlative with the severity of the diseases: with the upgrading of Braunwald classes, the concentration of NT-proBNP in patients with UA increased gradually; in patients with AMI it also raised gradually with the upgrading of killip classes; furthermore, the plasma concentration of NT-proBNP in patients with AIM increased much more than that in patients with UA when they are at the similar NYHA functional class.

CONCLUSIONPlasma concentration of NT-proBNP in patients with ACS might be a reliable biochemical marker which can objectively indicate the degree of this diseases.