| The morphological changes of left ventricle is directly related with the prognosis of patients with primary hypertension. There are higher mortality and more cardiovascular events in the patients with left ventricular hypertrophy (LVH) than those without and the left ventricular concentric remodeling has proved to be an independent predicting factor to cardiovascular events. As one of the main decisive factors of left ventricular after-load, the reduced distensibility of the aortic will increase the wall stress of left ventricle at systole and eventually result in LVH and/or left ventricular concentric remodeling. In the first part of the studies, we evaluated the changes of aortic distensibility and its relation with LVH and left ventricular concentric remodeling in patients with primary hypertension. The decrease in distensibility of large arteries is the important pathophysiological basis as well as an independent risk factor of cardiovascular and cerebral events. The wall structural change of large arteries was the major cause of the impaired compliance and distensibility. Up to now, the integrated backscatter (IBS) has been used on the studies of myocardium and its application on carotid have not been reported yet. In the second part of the present studies, we investigated the structural changes of carotid wall and its relation with the functional changes evaluated by the new modality of the integrated backscatter. The remodeling of cardiovascular system resulting from hypertension includes not only left ventricle but also left atrium. Recently, the functionof left atrium has drawn more attention. Left atrial ejection force (LAEF) is a term to indicate the force which ejects blood into left ventricle by active contraction of the left atrium during atrial contraction period. LAEF is regarded to be a better index than others to describe the function of left atrium because it contains two factors of both speed and volume. In the third part of the studies, we investigated the changes of LAEF in hypertension patients and its influencing factors.Part 1: Correlation of aortic distensibility with concentric remodeling of left ventricle in patients with primary hypertensionObjectives: To explore the changes of aortic distensibility and its influencing factors and its relation with the concentric remodeling of left ventricle in patients with primary hypertension.Methods: In the first part of studies, 32 patients with hypertension were included (17 men, 15 women, mean age 44.3±7.4 years old, ranged from 32 to 65 years). Twenty-seven normal subjects were included as the control group (15 men, 12 women, mean age 43.9±6.2 years old, ranged from 31 to 61 years). The normal subjects had no history of hypertension, family hypertension history, diabetes and other cardiac diseases, and underwent physical examination, electrocardiography, x-ray chest examination and echocardiography to roll out cardiovascular diseases. The patients with hypertension were asked to stop taking anti-hypertensive medicines at least for 7 days with informed consent of them before the study. Transthoracic echocardiography was performed with HP-sonos 5500 ultrasound systems interfaced with 2.5-3.5 MHz transducers. The patients were in a left lateral position during the examination and the II-lead electrocardiogram were recorded synchronously. M-mode echocardiogram of the aortic wall 3cm above the aortic ring were videotaped by National AC 6200 video tape recorder for following measurement. The inter-ventricular septum thickness (IVST), posterior wall thickness(PWT) and the dimension at end-diastole (Dd) of the left ventricle were measured at left ventricular long axis view using Penn's method. The relative wallthickness (RWT) was defined as (IVST+PWT)/Dd, and the left ventricular mass (LVM) calculated by the formula as follows: LVM=1.04 (IVST + PWT + Dd)3 ? Dd3] ?13.6(g). The left ventricular mass index (LVMI) was calculated by formula LVMI=LVM/ body surface area and the weight index (WI) calculated by WI=weight/h...
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