| PrefaceEvidence has implicated left ventricular remodeling in patients with essential hypertension is the most important prognostic factor associated with adverse cardiovascular events, including heart failure and sudden cardiac death. Fibrous tissue accumulation is an integral feature of the adverse structural remodeling of cardiac tissue which leading to myocardial fibrosis ( MF). It increases myocardial stiffness , promotes abnormalities of cardiac function and provides a pathological structural basis for the appearance of heart failure. Many experts believe MF is the decisive factor in leading to myocardial dysfunction and failure and associated with the prognosis of hypertension patients. At present, antihypertensive therapies are largely based on prevention and regression of MF. So it is important to evaluate the degree and extent of MF. Although cardiac biopsy is the reliable method, it is invasive and difficult to sample, not useful for wide - scale application. Noninvasive monitoring of MF by use of serological markers of collagen turnover could prove a clinically useful tool. An emerging experimental and clinical experience holds promise for the use of radioimmunoassays of various serological markers of fibrillar collagen type I and type III turnover. The measurement of serum concentrations of procollagen type I C -terminal peptide (PIP) and procollagen typeIII N - terminal peptide ( PIIIP) may provide indirect diagnostic information on both the extent of MF and the ability of antihypertensive treatment to reduce MF. Not like PIIIP, PIP derived from its procolla-gen completely, so PIP is more accurate than PIIIP.MF first impairs myocardial diastolic function, whose changes may provide indirect information on the degree of MF. Tissue Doppler imaging ( TDI) is a new echocardiographic technique and can evaluate diastolic function by measuring mitral annular velocities during diastole. The aim of this study was to (1) investigate the changes of serum PIP in essential hypertensive patients and assess the degree of MF indirectly , ( 2 ) measure the plasma concentration of endothelin - 1 (ET -1) and investigate the possible roles of ET -1 in the pathogenesis of MF, ( 3 ) assess diastolic function by measuring mitral annular velocities during diastole by TDI and determine the relation between the changes of diastolic function and the degree of MF.Materials and MethodsStudy SubjectsWe studied 50 patients with essential hypertension who had never treated or withdrawal from antihypertensive drugs at least two weeks, without history of coronary heart disease, cardiovalvular disease, diabetes mellitus, or liver, lung, kidney and bone metabolic disease. All patients were in sinus rhythm and had normal systolic function without segmental wall motion abnormalities. And 30 healthy examination people matched with the patients for sex and age as a control group. Their height, body weight and blood pressure were measured.Sample preparation and parameters measurements4ml fasting venous blood was collected: 2ml blood was mixedwith anticoagulant and plasma was separated, 2ml blood for serum prepared. The plasma concentrations of ET - 1 were measured by specific radioimmunoassay. The serum concentrations of PIP were measured by ABC - ELISA method. Fasting glucose and serum cholesterol were examined.EchocardiographyData and images were taken by a HP - SONOS 5500 ultrasound system with TDI technology: ( 1) The M - mode echocardiographic study of the routine parameters was performed first. Left ventricular mass index ( LVMI) was determined according to the formula introduced by Devereux et al and was normalized by body surface area. LVMI > 124g/m2 in male and LVMI > 110g/m2 in female were considered as left ventricular hypertrophy ( LVH). The hypertensive patients were divided into LVH group and NLVH group. (2) Then turn to the velocity model of TDI: a sample volume was placed at the follow 4 sites of the mitral annular: septa and lateral sites from the apical 4 -chamber views, anterior...
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