Background Recent studies demonstrated that N-terminal pro-brain natriuretic peptide(NT-pro BNP) increases in patients with diabetes mellitus and raised concerns about the diagnostic validity of NT-pro BNP in assessment of cardiac function in patients with hyperglycemia.Current investigation was carried out to observe the influence of hyperglycemia on the correlation of NT-pro BNP and cardiac function index in patients with acute coronary syndrome(ACS).Methods Fifty patients with ACS were enrolled and divided into hyperglycemia group(fasting plasma glucose(FPG) ≥ 6.1 mmol/L) and euglycemia group(FPG < 6.1 mmol/L).All the patients underwent routine transthoracic ecocardiagraphy and tissue Doppler imaging(TDI) investigation.Blood sample were obtained with 24 hours of hospitalization for measuring of NT-proBNP level.Relation between TDI-Tei index and the level of NT-proBNP were analyzed in the two groups respectively.Result TDI-Tei index,systolic index and diastolic index were all significantly higher in hyperglycemia group than that in euglycemia group(0.679 ± 0.139 vs 0.600 ± 0.093,P = 0.022;0.294 ± 0.074 vs 0.258 ± 0.035,P = 0.036;0.385 ± 0.069 vs 0.342 ± 0.068,P = 0.032).TDI-Tei index was significantly negatively correlated with the level of log NT-pro BNP in both hyperglycemia group and euglycemia group(rp = 0.673,P = 0.000;rp = 0.354,P = 0.000).Conclusions(1)Cardiac function in patients with ACS complicated with hyperglycemia is inferior to that in patients with euglycemia;(2)Assessment of cardiac function with NT-proBNP is reliable in patients with hyperglycemia. Background Recent studies demonstrated of that N-terminal pro-brain natriuretic peptide (NT-pro BNP) increases in patients with diabetes mellitus and raised concerns about the diagnostic validity of NT-pro BNP in assessment of cardiac function in patients with hyperglycemia. Current investigation was carried out to observe the influence of hyperglycemia on the correlation of NT-pro BNP and cardiac function index in patients with acute coronary syndrome (ACS). Methods Fifty patients with ACS were enrolled and divided into hyperglycemia group (fasting plasma glucose (FPG) ≥ 6.1 mmol / L) and euglycemia group (FPG <6.1 mmol / L) .All the patient underwent routine transthoracic ecocardiagraphy and tissue Doppler imaging (TDI) investigation. Blood sample were obtained with 24 hours of hospitalization for measuring of NT-proBNP level. Relation between TDI-Tei index and the level of NT-proBNP were analyzed in the two groups respectively. Result TDI-Tei index, systolic index and diastolic index were all signi ficantly higher in hyperglycemia group than that in euglycemia group (0.679 ± 0.139 vs 0.600 ± 0.093, P = 0.022; 0.294 ± 0.074 vs 0.258 ± 0.035, P = 0.036; 0.385 ± 0.069 vs 0.342 ± 0.068, P = 0.032) Tei index was significantly negatively correlated with the level of log NT-pro BNP in both hyperglycemia group and euglycemia group (rp = 0.673, P = 0.000; rp = 0.354, complicated with hyperglycemia is inferior to that in patients with euglycemia; (2) Assessment of cardiac function with NT-proBNP is reliable in patients with hyperglycemia.