The Use Of Plasma B-type Natriuretic Peptide Levels In Evaluation Of Prognosis And Risk Stratification Of Different Therapy In Patients With Acute Coronary Syndrome

Objective:To analyze plasma BNP levels in different therapy in patients with acute coronary syndrome(ACS),and to study BNP levels in evaluation of diagnosis,prognosis and risk stratification of patients with ACS.Methods:221 patients with ACS were recruited whose latest onset time was within 6 hours.They were divided into 3 groups:Group 1(ST elevation myocardial infarction,STEMI,n=83) consists of 35 patients received early percutaneous coronary intervention(PCI),20 patients received delayed PCI,and 28 patients received drug therapy;Group 2(non-ST elevation myocardial infarction,NSTEMI,n=69) is composed of 25 patients received early PCI,23 patients received delayed PCI,and 21 patients received drug therapy;and Group 3(unstable angina,UA,n=69) includes 22 patients received early PCI,27 patients received delayed PCI, and 20 patients received drug therapy.Blood samples for BNP were drawn at admission,48 hours and 7days from the onset,respectively. Patients received echocardiography 1 month after the onset.The patients were followed up for 3 months on average,but each individual's test was ended if the following clinical events was observed such as heart failure, angina,arrhythmia and mortality.Results:1.A significant increase in BNP levels was observed in Group 1 (64.2pg/ml) compared with the other groups.Group 2(34.9pg/ml) had higher BNP levels than Group 3(13.9pg/ml)(P＜0.01).There was a significant correlation between BNP and troponinⅠ(TnⅠ) level in Group 1 and Group 2(r=0.724 and 0.675,P＜0.001).2.BNP in evaluation of prognosis of the patients with ACS2.1 BNP levels at 7 days from the onset in patients with ACS showed a significant negative correlation with LVEF in 1 month(P＜0.001).BNP levels at 7 days from the onset in patients with STEMI showed a significant positive correlation with Tei(r=0.582,P＜0.001).2.2 In comparison with the STEMI/NSTEMI patients with normal LVEF (＞40%),BNP levels increased significantly in the patients with abnormal LVEF(≤40%).(1500 pg/ml vs 398.25 pg/ml;824 pg/ml vs 162 pg/ml,P均＜0.001)2.3 Followed up for 3 months,BNP level was significantly increased at 7 days from the onset in patients to whom heart failure happened.BNP level of 7 days from the onset≥100pg/ml indicates higher incidence of heart failure,mortality and cardiac events within 3 months. 3.Difference of BNP among the ACS patients with different therapyBNP levels were significantly decreased at 48 hours and 7days from the onset in patients with STEMI and NSTEMI received early PCI(P＜0.05).BNP level was significantly decreased at 7days from the onset in patients with UA received early PCI(P＜0.01),but there was no considerable difference between the patients with delayed PCI and with medicine therpy.Incidence of heart failure was decreased among the ACS patients with early PCI.4.BNP level significantly increased in the patients with TIMI grade＜3 compared with the patients with normal TIMI grade(116pg/ml vs 25.4pg/ml,p＜0.001).Conclusion:The patients with STEMI/NSTEMI have higher plasma BNP levels than those with UA.BNP levels of 7days from the onset are capable of predicting incidence of heart failure,mortality and cardiac events.Early PCI can significantly decrease BNP levels and incidence of cardiac events and improve prognosis.BNP levels at admission are able to predict incidence of no-reflow phenomenon.