Relationship Between Estradiol And Ventricular Remodeling, NT-proBNP In Postmenopausal Women With Coronary Heart Disease

BackgroundCoronary atherosclerotic heart disease or coronary heart disease (CHD), is refers to the heart disease caused by a lack of oxygen to myocardial ischemia or necrosis due to the coronary artery atherosclerotic vascular cavity stenosis or occlusion or (and) functional change of coronary arteries (spasm),also known as ischemic heart disease.Coronary heart disease is a common disease, mainly due to the global death and dysfunction of the heart nowadays..Since the 1950 s, the morbidity and mortality of the coronary heart disease the population is rising. In developed countries, this upward trend is particularly prominent. In 1991 the American heart association released, coronary heart disease deaths in 1988 accounted for 45.3% of the total death, about 1/5 of americans in the 65-year-old former death from cardiovascular disease. The prevalence of coronary heart disease in our country is lower than that of developed countries, but showed a trend of increase significantly in recent years, according to"the Cardiovascular disease of China 2013", the current national cardiovascular disease is estimated to be 290 million, one in every five adult is suffering from cardiovascular disease.2008 China Health Survey results show that: the prevalence of the heart disease is15.9‰ in urban areas,4.8‰ in rural areas,7.7‰ in urban and rural areas, which has a significant increase compared with the third survey in 2003.In recent years, with the development of science and technology and people to continuously improve the prevention and treatment of coronary heart disease, coronary heart disease mortality in men showed a downward trend. However, due to lack of awareness of the special nature of women with coronary heart disease and its prevention and control work has been more lag, coronary heart disease mortality in women but on the rise. Review of more than 20 years of data show that the developed countries men of coronary heart disease mortality has declined obviously, whereas women showed a trend of rising steadily. Cardiovascular morbidity and mortality in developing countries continues to increase, also the growth of the female cardiovascular disease is more apparent. Large-scale epidemiological data shows, the the number of death from cardiovascular disease in worldwide each year is larger in women than in men. In China, the cardiovascular disease has become the first cause of death in women in China. Therefore, the understanding and research of cardiovascular disease (CVD) of women is particularly urgent.Epidemiological surveys have shown that women with coronary heart disease about 10 years later age than men, the proportion of the incidence of coronary heart disease between men and women before menopause is 1:3-10, postmenopausal women close to or above the same age of men, suggesting that women of this advantage is mainly related to the protective effect of estrogen.Estrogen is fat soluble steroid hormones, including estrone, estradiol and estriol. Estradiol is the most important human ovarian secretion of hormones, with the blood circulation can spread to the target tissue and thus play a special effect. Estrogen may effect lots of tissues, in addition to the regulation of reproductive system, in the prevention of cardiovascular disease also play an important role.Currently recognized as estrogen for cardiovascular protective mechanism includes:an increase in the formation and release of nitric oxide and prostacyclin in endothelial cell causes transient vasodilation, and, the relaxation of vascular smooth muscle and the vasodilation by opening the calcium channel by cGMP-dependent mechanism; the role of lowering blood lipid and lipoprotein (a), the prevention of the occurrence of abnormal lipid and atherosclerosis effectively; the inhibition of platelet aggregation and the reduction of the concentration of plasma fibrin improve the hemodynamics; the inhibition of inflammatory cytokine production, reduce the inflammatory response; protection of endothelial cells, inhibition of vascular smooth muscle cell proliferation, migration and extracellular matrix synthesis make atherosclerotic plaque regression, which has anti-atherosclerotic effect.Is about protection of estrogen on the cardiovascular system and prevention of coronary heart disease has more clear, but for patients already suffering from coronary heart disease, what effect on endogenous estrogen on the cardiovascular system is unclear.Ventricular remodeling is due to hypertrophy, degeneration, necrosis, apoptosis increased interstitial collagen synthesis and myocardial cells, composition changes and myocardial fibrosis cause heart enlargement, increased heart mass. A variety of cardiac diseases such as chronic ischemic heart disease, chronic heart failure can cause cardiac damage,which leads to ventricular remodeling. Previous studies have mostly concentrated on ventricular remodeling in hypertension and heart failure population, less about the people with coronary heart disease. Nowadays the ventricular remodeling is an important independent risk factor for cardiac events, which relates to arrhythmia, heart failure and sudden death. How to slow down and reverse ventricular remodeling become common research focus at home and abroad. The occurrence and development of ventricular remodeling is a very complicated process. The pathogenesis of ventricular remodeling includes:the activation of neuroendocrine and cytokines, the change of intracellular signal transduction, the abnormation of gene expression,etc. As an important female hormone, estrogen is involved in the regulation of ventricular remodeling is not entirely clear.B-type natriuretic peptide (BNP), namely the brain natriuretic peptide, is a kind of composed of 32 amino acid polypeptide hormone produced by the heart. It comes mainly from the ventricle.Myocardial ischemia, injury, necrosis, cardiac wall tension and the heavily pressure can stimulate the synthesis and secretion of BNP. Its main physiological role includes:Against the renin-angiotensin-aldosterone system and the retention in sodium and water; Antagonize the sympathetic nervous, relaxation of vascular smooth muscle which reduces the peripheral resistance; The relaxant effect of coronary artery; Inhibition of myocardial fibrosis; To prevent the thrombosis. It has been demonstrated in patients with heart failure that BNP levels were significantly increased, but few studies about BNP in coronary heart disease patients. Recent studies suggest that foreign sodium plasma B-type natriuretic peptide (BNP) in patients with acute coronary syndrome (ACS) patients can be increased, and can be used as prognostic markers in patients with ACS. NT-proBNP and BNP are cleavage from the same brain natriuretic peptide precursor, because of the NT-proBNP biological long half-life, plasma concentration is higher and more stable than the BNP,so it is more suitable for clinical testing. Present study suggests that, in patients with acute coronary syndrome and stable angina patients, the plasma concentration of NT-proBNP has become a bad long-term independent predictor of cardiovascular events. At home and abroad in the NT-proBNP expression regulation mechanism research is not much. Endogenous estrogens as cardiovascular protection factor, is an important part of the endocrine system, whether takes part in the secretion of serum NT-proBNP is not clear.ObjectivesIn postmenopausal women suffering from coronary heart disease patients as the research object, the setting of coronary artery disease after menopause women for comparison, using the modern advanced detection technology, explore the relationship between estradiol and ventricular remodeling,NT-proBNP in postmenopausal women with coronary heart disease. Explores what estrogen on the cardiovascular system plays a role and hou estrogen affects the cardiac structure and the NT-proBNP secretion mechanisms in patients with coronary heart disease.Methods1.CHD group inovlve 50 postmenopausal women with chronic heart disease from Cardiology Department in Nanfang Hospital affiliated to Southern Medical University during 2012.6 to 2013.6. All patients had typical angina and electrocardiographic changes (when the onset of chest pain or during exercise stress test). Coronary angiography or coronary CTA confirmed single or multiple vessels coronary artery stenosis ≥50%. Exclusion criteria:those who were experiencing active rheumaticheart disease,congenital heart disease,acute coronary syndrome,acute phase of cerebrovascular disease,chronic bacteria infection disease and serious damage of liver and kidney function were excluded as well as those users of sex hormone within 3 month. Control group included 40 postmenopausal women with other ardiovasculr iseases but without CHD. Patients with serious hypertension,infection diseases,dysfunctionof liver and renal were excluded.2.Collect blood samples of all patients in the next morning after hospitalization procedure and measurement of their height and weight.The samples were then processed and storage in the refrigerator at the temperature of -40℃.Detect the amount of estradiol and NT-proBNP after all specimen had been collected, all cases routinely received test of echocardiography,which is performed by two distinct doctors respectively.According to the standard plane recommended by American association of ultrasound,every patients were measured 3 times and took the average of LVEDd,then follow the recommended forluma to get the parameters of LVMI. 3.Two independent t test was applied to analyze the difference between case group and control group.The difference among subgroups was analyzed with one-way-ANOVA. Chi-Square test was used to analyze nonparametric data. Partial correlation was applied to detect the correlationship of estradiol and other material.Pearson correlation analysis was performed to analyze the relationship between estradiol, NT-proBNP and LVMI as well as LVEDd.Results1. Coronary heart disease group compared with control group in clinical basic situation:Chi-Square test showed no significant difference between two groups in incidence of age,blood pressure,BMI.(P> 0.05)2. The differences in the levels of the estradiol,NT-proBNP, LVEDd and LVMI between coronary heart disease group and control groupCompared with the control group, serum estradiol levels were significantly reduced CHD; and LVEDd, LVMI, NT-proBNP levels were significantly higher (P< 0.01, P< 0.05)3. The correlationship of estradiol and NT-proBNP,LVEDd,LVMI in coronary heart disease groupIn CHD group the level of estradiol was significantly negatively correlated with LVEDd (r=-0.731, P<0.001), LVMI (r=-0.768, P<0.001), NT-proBNP (r=-0. 565,P<0.001).Conclusions1. Plasma estradiol levels in postmenopausal women with coronary heart disease than women without coronary heart disease significantly reduced, suggesting that endogenous estrogen has a protective effect on the cardiovascular, can prevent the occurrence of coronary heart disease.2. The LVEDd,LVMI, NT-proBNP level in postmenopausal women are different between coronary heart disease group and the control group, prompt that coronary heart disease (CHD) has influential role on cardiac structure and the secretion of the NT-proBNP3. In CHD group the level of estradiol was significantly negatively correlated with LVEDd, LVMI, NT-proBNP level. It prompts that endogenous estrogen is involved in the regulation of ventricular remodeling as well as the secretion of the NT-proBNP in vivo,. Estradiol continues to play a protective role in patients with coronary heart disease.