The Clinical Study Of Carvedilol On Cardic Function Neurohormonal Activation And Vascular Endothelial Function In Patient Withcongestive Heart Failure

Background and ObjectiveCongestive heart failure(CHF) is end-stage of various heart diseases such as hypertension, valvular heart disease, myocardial infarction and ischemic heart disease. Although the clinical medications of CHF have been developing in the past decade, the morbidity and mortality of CHF continue stepping up. With the advancement of cytobiology and molecular biology, people gradually realize that the neurohormonal activation paly a important role in the development and progression of CHF. β -blockers are one of them which have been used to treat CHF recently. Of them, Carvedilol, a new kind of β-blocker, has been used in the treatment of CHF. The purpose of the present study is designed to systematically assess the effects of Carvedilol on the neurohormonal activation, vascular endothelial function and its clinical efficacy in patients with CHF. MethodsThe study groups comprised 60 patients with CHF. The following diseases were excluded during the period of study: Bronchial asthma, Atrio-ventricular conductive block(AVB), Sick sinus syndrome, Cardiac shock , severe bradycardia. All patients were divided Randomly into two groups, Carvedilol group and control group. Thepatients in control group had been given the routine treatment, which included digitalis, diuretic and so on, except for Carvedilol. The patients in Carvedilol group were treated with Carvedilol(beginning with 3.125mg/qd , increasing dosage gradually to 12.5mg/bid in 8 weeks and keep up with the dosage). The other treatments were identical with the control group. The symptoms and signs of CHF had been observed and recorded everyday for each in-patient during the admission according to NYHA classes. As for the out-patients, the follow-up check had been performed weekly in the clinic. All patients were drawn blood for the chemical analysis in which the renin, angiotonin, aldosterone; endothelin, nitrogen monoxidum had been measured before the treatment and 6-8 months after the treatment. All patients were examined respectively by echocardiography for the measurement of the following indexes: Peak velocity (VP) ; pre-ejective period (PEP) ;ejective time (ET) ;accelaration time (AT) ;ejection fraction ( EF) ; dp/dtmax; -dp/dtmax; iso-volumetric relaxation period (IVRT) ;E;A and E/A. Results:(l)Comparing with the control group , the plasma levels of PRA, AT II, ALD,ET decreased significantly (p<0.01) , the plasma level of NO significantly increased (p<0.01) in Carvedilol group in 6-8 months after the treatment.(2) Comparing with the control group, EF; VP; dp/dtmax; and the absolute value of -dp/dtmax increased significantly(p<0.01); PEP,ET,AT,IVRT shortened significantly(p<0.01). E and E/A tend to be increased ; A tend to be decreased in Carvedilol group. (3) Comparing with the control group, the clinical symptoms had been improved obviously in Carvedilol group (p<0.01) . Conclusions:The results of the present study showed that Carvedilol for the long-term treatment of patients with CHF not only suppresses the over-activated RAS, but also reverses the dysfunction of vascular endothelium and improves cardiac function with the characterization of the decreased level of plasma renin, angiotonin, aldosterone and endothelin, the increased nitrogen monoxidum; the increased EF,VP, dp/dtmax andthe absolute value of -dp/dtmax; the shortened IVRT,PEP,ET,AT and the improved clinical symptoms in Carvedilol group.