The Relevant Study Of Brain Natriuretic Peptide And Left Ventricular Hypertrophy In Essential Hypertension

Objective:The pathogenesis of hypertension is complex. Besides the diseases of heart and blood vessel,the disorders of autonomic nerves and the abnormal regulations of body fluid play important parts in the occurrence of hypertension.To be emphasized,body fluid factors cannot be neglected in pothogenic progress. BNP is an inside natriuretic peptide in human body.When heart function is injured by various kinds of pathologic elements,ventricle can secrete this substance as a form of compensation and protection. In the progress of hypertension, the increasing blood pressure can cause myocardial hypertrophy.Researches predict that left ventricular hypertrophy is a significant symbol which affects pregnosis. Because it can accelerate the development of atherosclerosis, aggravate myocardial aschemia,result in the occurrence of myocardial infarction, arrhythmia, sudden death and congestive heart failure.This test caculated the quality index of left ventricle(LVMI)through echocardiography ,then judged the extent of LVH .The purpose was surpposed to study the relevance of BNP and LVMI and inquire into the effect of BNP in LVH.In recent years,many researchers treated hypertension patients with medicine. To discuss the effect of body fluid factors in hypertension ,they detected the change of body fluid factors when blood pressure was being observed.EH patients would be treated with three types of drugs in this experiment ,then BNP level would be measured and contrasted among those treatments.Methods:116 essential hypertension patients were enrolled from November 2005 to June 2006.(90mmHg≤NBP≤110 mmHg, 140mmHg≤SBP≤180mmHg,excluding secondary hypertension and other organic heart diseases).They were divided into three groups in random and contrast.After 2 weeks′clearing time,they took Benazepril 10mg Qd,Valsartan 80mg Qd and Valsartan 80mg+HCTZ 12.5mg Qd respectively at 7:00-9:00,4 weeks altogether.Blood samples were obtained through venipuncture before and after treatment.All other drugs which influnce blood pressure were prohibited during experiment period. ECG,UCG and chemical examination were carried in every patient.Their general conditions were registered.BNP and the relational indexes of UCG (LVDd,IVS, LVPW,EF,E/A) were recorded. According to diagnostic criterion of LVH (UCG:LVMI:Male≥122g/m2 , Female≥115g/m2).BNP level was contrasted between LVH and unLVH,then correlation was analyzed in BNP and indexes of UCG.BNP level of every sample was self-contrasted in each group before and after interference,also distinguished among three groups. Continuous variables were expressed as the main value±standard deviation(SD). Relevance of BNP and LVH was evaluated by Correlation Test.Self-contrast in each group was compared using Paired-Samples T Test, Independent-Samples T Test was performed to determin the differences between every two groups. SPSS13.0 softcase was adopted.A P value <0.05 was considered statistically significant.ResultsAmong the 116 subjects who were hypertension patients,including 62 males and 54 females,with a mean age of 53.28±12.14 years.38 individuals in Group Benazepril ,39 in Group Valsartan ,39 in Group Valsartan+HCTZ .The baseline characteristics such as gender, age, blood pressure,heart rate, BMI,course of disease were not significantly different among these groups (P>0.05).According to the LVMI criterion of UCG:38 subjects suffered LVH.Their BNP level was much higher than that of unLVH.On the contrary,E/A and EF(%) were much lower.BNP has positive relation with LVMI,but negative relevance with E/A and EF(%).Compared with curative effects of Benazepril and Valsartan , that of Valsartan+HCTZ was more significant on DBP(P >0.05),but not on SBP (P <0.05)The average BNP level was reduced: Benazepril 2.985±6.460 pg/ml, Valsartan 2.949±8.908 pg/ml, Valsartan+HCTZ 6.827±8.181 pg/ml.Self-contrast in each group was statistically diverse (P<0.05).Comparisons between every two groups:BNP of Valsartan +HCTZ was reduced more than the other two groups(P<0.05). There were not significant differences between single Benazepril and Valsartan on changes of BNP .Conclusions1 Compared with unLVH,BNP level of LVH was much higher.According to UCG, BNP had positive relation with LVMI ,so BNP is an important factor in LVH of EH patients,meanwhile,BNP had negative relation with E/A and EF(%).2 Benazepril and Valsartan could reduce blood pressure of EH patients as well as BNP level,and they were not different on changes of BNP.3 The curative effects of Valsartan+HCTZ on DBP was better than single Benazepril or Valsartan ,so as the influnce to BNP.