| With the population aging and acceleration of living rhythm, incidence of hypertension keeps rising year by year. If not controlled effectively, hypertension can cause damage to target organs. The main damage to target organs includes changes of ventricular structure, changes of arterial structure, renal damage, albuminuria, and eyeground arteriosclerosis, etc. Therefore, the goal of hypertension treatment is not only to control blood pressure itself, but also to pay attention to target organs protection. Blood vessels are usually involved first in hypertension. In hypertension, a remarkable change of blood vessels is vascular remodeling. Vascular remodeling is probably the most important factor affecting the development of hypertension, and thus in the clinical treatment of hypertension, we not only have to lower blood pressure, but we also have to rectify abnormality of vascular structure and reverse the process of vascular remodeling. The increase in carotid intima-media thickness (IMT) can act as an independent risk factor to predict the incidence and fatality of cardiovascular diseases, and antihypertensive treatments can reverse carotid IMT. Former researches revealed that carotid IMT decreases and gets near to normal with effective control of blood pressure. Therefore, to measure carotid IMT can serve as a surveillance index of observing macrovasculopathy in early stage of hypertensive patients and an index of evaluating treatment effectiveness of drugs. Heart is a target organ subject to hypertension most often, the main manifestation of which is left ventricular hypertrophy (LVH), which is an independent risk factor to increase prevalence and fatality of cardiovascular diseases. So it is a vital goal in hypertension treatment to reasonably select antihypertensive drugs to reverse or even prevent LVH and to improve its diastolic and systolic functions. One pathogenic mechanism of hypertension is the activation of renin-angiotensin-aldosterone system (RAS). The antihypertensive function of angiotensin converting enzyme inhibitor(ACEI)is to inhibit peripheral and tissular angiotensin converting enzyme, to decrease generation of angiotensin II (AngⅡ), and meanwhile to reduce bradykinin degradation by inhibiting kininase.ACEI prohibits hyperplasia of cardiovascular cells, and prevents or reverses remodeling of heart vessels and kidney. Angiotensin II receptor inhibitors (ARB) selectively inhibit angiotensin II receptor 1, which results in functions of antiproliferation, apoptosis inducing, and nitric oxide(NO)generation stimulating, mediated by angiotensin II receptor(AT2).ACE inhibitors are similar to, while different from ARB in mechanism. They both can block renin-angiotensin-aldosterone system (RAS), but blockage of ACE is incomplete, so there is likely to be other non-ACE ways for angiotensin II generation. ARB blocks functions of angiotensin II on receptor levels, and thus the inhibiting function of renin-angiotensin-aldosterone system is more powerful. Thiazide diuretics were formerly used in patients with mild to moderate hypertension. The antihypertensive reaction to diuretics is significantly different between singles. Toxicity of thiazide diuretics is low, but long-standing use can cause electrolyte disorder. A small dose of thiazide diuretics can reduce the occurrence pf these side effects. During use of diuretics, blood volume decreases, which will activate renin-angiotensin-aldosterone system (RAS), increase renin activity andaldosterone level of the plasma, and thus can partly antagonize antihypertensive functions of diuretics. ACEI and ARB can counteract the above actions of diuretics, so antihypertensive potency of thiazide diuretics combined with ACEI and ARB is evidently enhanced. Combination use of antihypertensive drugs of different mechanisms can optimally control many risk factors or subsequent diseases in hypertensive patients, which benefit the protection of target organs more, further reduce the occurrence of cardiovascular incidents, and improve treatment compliance and quality of life. Thiazide diuretics and ACEI have fine synergetic effects,. On one side, diuretics activate renin-angiotensin-aldosterone system, while ACEI inhibit renin-angiotensin-aldosterone system; on the other hand, the mild potassium sparing effect of ACEI lessens the possible side effect of hypokalemia of thiazide diuretics, and therefore the combination use of them can both enhance the antihypertensive effect and lessen side effects. We utilized elderly hypertensive patients as research object, aimed at observing the antihypertensive effect and influence on carotid and heart structure ofcombination use of ACEI and ARB with small dose of Hydrochlorothiazide to treat elderly hypertensive patients. The method is to select 60 hypertensive patients of 1～2 degree, aged 65-80, randomly divided to groups A and B. Group A take the combination of Irbesartan and Hydrochlorothiazide. Group B take the combination of Enalapril and hydrochlorothiazide.Observing 6 monthes After 2 weeks of washing out period, the selected patients took part in the experiment. The two groups were examined in blood pressure, function of liver and kidney, and electrolytes, and examined with Color Doppler Ultrasonography in carotid and heart. The intima-media thickness of carotid arteries, The interventricular septum thickness, the left ventricular posterior wall thickness, and the left ventricular diameter at end-diastole were measured and the left ventricular mass index was calculated. Statistical analysis was used to compare the significance of the two groups. The experiment revealed: 1.Blood pressure was smoothly lowered in both group A and B after treatment, and there was no statistical significance between the two groups. 2. Adverse effects: 1 case of headache(3.33%), 1 case of dizziness(3.33%)and 1 case of mild cough(3.33%)in group A. 2 cases of headache(6.67%)and 4 cases of cough (13.33%)in group B. Group A was significantly less than group B in adverse effects ( p<0.05 ) .There was no statistical significance between them in serum creatinine and serum potassium(p>0.05).3. After treatment, the intima-media thickness of carotid arteries was obviously decreased(p<0.05).There was no statistical significance between the two groups. 4. Changes in heart structure: after treatment: the end-diastole interventricular septum thickness and the left ventricular posterior wall thickness were significantly decreased. Left ventricular mass index was obviously reduced, which was statistically significant. Thus it can be seen, thiazide diuretics and ACEI have good synergetic effects. The combination use of them can obviously lower blood pressure, reverse cardiovascular remodeling, and the mild potassium sparing effect of ACEI and ARB lessens the possible side effect of hypokalemia of thiazide diuretics, and therefore the combination use of them can both enhance treatment effect and lessen side effects. Conclusions below can be reached: 1. Combination use of Enalapril and Irbesartan with small dose of Hydrochlorothiazide to treat elderly hypertensive...
|
PDF Full Text Request