Relationship Between Vascular Endothelial Dysfunction And Left Ventricular Hypertrophy In Essential Hypertension Patients

Background and purpose:Vascular endothelial dysfunction(ED) existing in hypertension, may be one of the early marker of hypertension, and also one of the causes. It plays an important role in the development of hypertension, and hypertension itself can also aggravate the vascular endothelial dysfunction (ED). In the last ten years, flow-mediated dilation (FMD) of the brachial artery became an important index to evaluate the function of vascular endothelium, and left ventricular mass index (LVMI) was an important index to reflect the injury of target organ in the progression of hypertension. Nowadays, there's less study about the relationship between vascular endothelial dysfunction (ED) and left ventricular hypertrophy (LVH) in essential hypertension patients. The purpose of our study is to investigate the relationship between FMD and LVMI in essential hypertension (EH).Methods:55 patients (male: 29; female: 26; age: 38~70 years old; average age 56.6±8.1 years old) with essential hypertension were enrolled, all never received anti-hypertension treatment or stop the treatment over two weeks. And 25 healthy people as the normal control (matched with age, sex, smoking, body mass index) were choosed. Secondary hypertension, coronary atherosclerotic heart disease, diabetes, dyslipdemia, thyroid disease, valvular heart disease, heart failure, infection, hypohepatia,renal disease and stroke were excluded. FMD of the brachial artery was examined by high-resolution ultrasonography technique and the inter-ventricular septum thickness (IVST), left ventricular posterior wall thickness (LVPWT)and left ventricular diastolic diameter (LVDD) were measured by echo-cardiography technique. The left ventricular mass and LVMI were calculated according to Devereux formulary. According to Framingham heart study, The hypertensive individuals were separated into two groups, left ventricular hypertrophy (LVH+) group and without left ventricular hypertrophy (LVH-) group.Results:There were no significant difference in age, sex, smoking, body mass index, the level of blood lipoprotein and blood-glucose among the three groups (p>0.05). The SBP, DBP, MBP both in patients with LVH and without LVH were higher than the control group (p<0.01), but no significant difference was found between LVH- and LVH+ groups (p>0.05). The LVMI was higher in patients with hypertensions (119.9±20.5)g/m2 than that in the control group (94.7±13.8)g/m2 (p<0.001). Compared with the normal control (12.0%±1.8%), FMD of brachial artery was lower both in patients LVH- and LVH+ (6.95%±1.3%; 6.3±1.0%; p <0.001), but there's no significant difference between the two groups. FMD correlated negatively with LVMI in hypertension patients (r=-0.551, p<0. 01), LVMI correlated positively with SBP, DBP and MBP (r=0.41, 0.28, 0.30, p<0.05). Multi-linear regression analysis indicates that LVMI is not correlated with FMD, age , SBP, DBP, MBP.Conclusion:FMD of brachial artery was impaired in proportion to the increase in LVMI in patients with essential hypertension.