Effect of atorvastatin on changes of heart function and plasma level of brain natriuretic peptide in acute myocardial infarction patients

Abstract

Objective To observe changes in plasma level of brain natriuretic peptide ( BNP), left ventricular function in acute myocardial infarction (AMI) patients and discuss the effect of atorvastatin in these patients. Methods Eight patients with acute myocardial infarction hospitalized from October 2006 to December 2008 in our department were enrolled in the study. The AMI patients were further randomly assigned into the conventionsl treatment group ( n = 38 ) and atorvastatin treatment group ( n = 42 ). In the conventional group all patients took ACEI, beta-blocker, nitrate drugs, aspirin and low molecular beparin as their conventional therapy without medication taboo. In the atorvastatin group all patients took atorvastatin 20 mg per day for three months in addition to the conventional treatment. Twenty healthy individuals were testified by coronary arteriongraphy and ultrasonic cardiogram selected as controls ( n = 20). LVEDd, LVEF and left ventricular fractional shortening (LVFS) of 80 patients with AMI and 20 healthy controls were examined by ultrasonic cardiography and their plasma concentrations of BNP were measured. As to the conventional and atorvastatin group, the parameters were tested on the day of hospitalization (within 24 hours of AMI) ,also at the 3rd week and 3rd month after treatment. All data were analyzed statistically by SPSS12. 0. Results There were no significant changes in LVEDd, LVEF, LVFS after 3-week treatment compared to pre-treatment ( P ＞ 0.05 ), but significant changes after 3-month treatment ( P ＜0. 01 ) in 2 AMI groups. Moreover, LVEDd, LVEF, LVFS in the atorvastatin group were significantly greater than the conventional group (P ＜ 0.05). The plasma levels of BNP measured within 24 hours of AMI onset in two treatment groups were significantly higher than the control group. The plasma BNP level decreased significantly after 3 - week and 3-month treatment( all P value ＜0. 01 )in both treatment groups and atorvastatin group showed even lower BNP level with comparison to the conventional group( P ＜0.05 ). The plasma BNP in myocardial infarction patients after three months of treatment were negatively correlated with LVEF( r1 = -0.48 ,r2 = -0.58 ,P ＜ 0. 01 ) which implied a close relationship between BNP and heart function. Conclusions The changes of plasma BNP is earlier than that of heart structure. The long-treatment usage of atorvastatin may improve cardiac function, decrease the plasma BNP and convert ventricular remodeling,which benefit patients besides lipid managing. The plasma BNP could be used as a sensitive indicator of the treatment response and a useful index for evaluating the heart function and pronosis in AMI patients. Key words: Acute myocardial infarction; Atorvastatin; Brain natriuretic peptide