The significance of serum NT-proBNP for the future risk evaluation of major adverse cardiac events in elderly patients with stable coronary artery disease

Objective To investigate the significance of serum N-terminal pro-B-type natriuretic peptide(NTproBNP) for the future risk evaluation of major adverse cardiac events(MACE) in elderly patients with stable coronary artery disease(SCAD).Methods A total of 810 elderly patients with SCAD were classified into non-MACE group(468 cases) and MACE group [342 cases,including cardiogenic readmission group(200 cases),nonfatal acute myocardial infarction(AMI) group(61 cases) and death group(81 cases) ] according to disease prognosis.The 342 cases of MACE group were classified into the short-term MACE group(180 cases) and the long-term MACE group(162 cases).The serum NT-proBNP levels of 40 healthy controls and 810 elderly patients with SCAD,which were followed up in the third month,in the sixth month and in the twelfth month,were determined by bi-directional lateral flow immunoassay.The results were analyzed statistically.The MACE were followed up and observed for an average of 24 months.Results The serum NT-proBNP levels at initial admission in the MACE group and non-MACE group were significantly higher than those in the control group(P 0.01),the serum NT-proBNP levels at initial admission in the MACE group were significantly higher than those in the non-MACE group(P 0.01),the serum NT-proBNP levels at initial admission in the short-term MACE group were significantly higher than those in the long-term MACE group(P 0.05),and the serum NT-proBNP level at initial admission in the death group and nonfatal AMI group were significantly higher than those in the cardiogenic readmission group(P 0.05).The serum NT-proBNP levels at initial admission were negatively correlated with the interval time of the patients with readmission and AMI [r =-0.359(P = 0.000),r =-0.458(P = 0.026) ].The serum NT-proBNP level was higher,and the incidence rates of MACE were higher.The incidence rates of MACE in different serum NT-proBNP level groups were significantly different(P 0.01),except the NT-proBNP 6 000 ng/L group.Before MACE,the top value of serum NT-proBNP in the MACE group was significantly higher than that in the non-MACE group,and the top value of serum NT-proBNP in the death group was significantly higher than that in the other groups(P 0.05,P 0.01).In the third,sixth and twelfth months of follow-up period,the serum NT-proBNP levels in the MACE group were significantly higher than those at initial admission(P 0.01).The serum NT-proBNP levels in the non-MACE group were significantly lower than those at initial admission(P 0.01),and were significantly lower than those in MACE group(P 0.01).Kaplan-Meier curve showed that the survival rate with different serum NT-proBNP levels had statistical significance(P 0.01).The death group with various diseases had no statistical significance for the serum NT-proBNP levels(P 0.05).Conclusions The incidence rate of MACE and the interval time of the MACE in elderly patients with SCAD are closely correlated with the serum NT-proBNP level at initial admission and with the changes of serum NT-proBNP levels and the top value of serum NT-proBNP in the follow-up period.The serum NT-proBNP determination for the MACE risk evaluation in elderly patients with SCAD has an important prognostic significance.