卡维地洛与普萘洛尔降低肝硬化门静脉高压患者肝静脉压力梯度效果的对比分析

目的探讨卡维地洛和普萘洛尔降低肝硬化门静脉高压患者肝静脉压力梯度(HVPG)的幅度、应答率以及用药后不良反应的差异,对卡维地洛降低门静脉压力的有效性和安全性进行评价。方法收集2010年10月-2012年1月在山东大学附属省立医院确诊的64名肝硬化门静脉高压患者,随机分为2组:普萘洛尔组(n=33)和卡维地洛组(n=31),根据血压和心率调整剂量,疗程7 d,均于治疗前后行HVPG测定及肝肾功能指标检测,比较2组患者HVPG降低的幅度及应答率,并观察患者低血压、腹水、肾损伤等不良反应的发生情况。计量资料组间比较采用t检验,计数资料组间比较采用χ2检验或Fisher精确概率法。结果卡维地洛组和普萘洛尔组的HVPG均明显降低,降低幅度分别为(28.30±22.19)%和(12.38±24.09)%,其中卡维地洛组降低更明显,差异有统计学意义(t=0.223 4,P=0.032)。2组应答率分别为:卡维地洛组56.7%(17/30),普萘洛尔组41.9%(13/31),2组差异无统计学意义(χ2=1.324,P=0.250)。卡维地洛组平均动脉压的降低较普萘洛尔组明显,差异有统计学意义(t=2.338,P=0.024),但患者未出现明显低血压的不良反应;2组患者胆红素、血肌酐和尿素氮在治疗前后无明显升高,亦无腹水生成或加重的趋势。结论本研究提示在短期内卡维地洛降低HVPG的作用较普萘洛尔显著,且无明显不良反应;其用于肝硬化门静脉高压的治疗是安全有效的。     

Hemodynamic effects of one week of carvedilol administration on cirrhotic rats

Background Carvedilol is a nonselective β-blocker with α₁-adrenergic blocking activity. It has been shown to decrease portal pressure in cirrhotic patients. The current study was undertaken to evaluate the possible mechanism of carvedilol on hemodynamics in cirrhotic rats with portal hypertension produced by common bile duct ligation. Methods Male Sprague-Dawley rats received either a sham operation or common bile duct ligation. Three weeks after surgery, both sham-operated and cirrhotic rats were randomly assigned to receive vehicle or carvedilol 5 mg · kg⁻¹ · 12 h⁻¹ by gastric gavage for 1 week. Hemodynamic measurements, serum biochemistry, serum nitrate/nitrite and 6-keto-PGF_1α levels, and aortic mRNA expression of eNOS and COX-1 were performed on the eighth day after drug administration. Results Carvedilol treatment did not affect serum biochemistry in either sham-operated or cirrhotic rats. In sham-operated rats, administration of carvedilol significantly decreased the heart rate without affecting other hemodynamic values. In contrast, in cirrhotic rats, administration of carvedilol significantly decreased the cardiac index, portal pressure, heart rate, and portal territory blood flow, and it significantly increased systemic and portal territory vascular resistances. The hepatocollateral resistance was significantly decreased, but the hepatic arterial blood showed no significant changes. In sham-operated rats treated with carvedilol, serum nitrate/nitrite and 6-keto-PGF_1α levels were not affected. In contrast, cirrhotic rats receiving carvedilol showed a significant decrease in serum nitrate/nitrite and 6-keto-PGF_1α levels, associated with a decrease in aortic mRNA expression of eNOS and COX-1 compared with those receiving vehicle. Conclusions Carvedilol decreased portal pressure through a reduction of splanchnic blood flow associated with a decrease in hepatocollateral resistance. Additionally, administration of carvedilol decreased endothelial-related vasodilatory activities.     

卡维地洛治疗肝硬化门静脉高压的研究进展

降低门体压力梯度是预防肝硬化静脉曲张出血的首要目的。卡维地洛具有非选择性阻断β受体、阻断α1受体及阻断钙通道的作用。回顾了卡维地洛在降低门静脉压力梯度方面以及预防静脉曲张出血的作用。分析表明卡维地洛较普萘洛尔可以更有效地降低门体压力梯度。卡维地洛与普萘洛尔或内镜套扎预防静脉曲张首次及再次出血疗效是相似的。未来大样本随机对照试验应该证实这些研究结果。     

门静脉高压症血流动力学改变的发病机理

门静脉高压症（PHT）与肝内循环、体循环和门体侧支循环的血流动力学改变有关。肝内阻力增加和高动力循环侧支血管的扩张在门静脉高压的发病机理中起到了重要作用。不同严重程度的肝硬化均存在能广泛影响人体的血流动力学紊乱。门静脉高压和高动力循环是肝硬化患者发病和死亡的主要原因。而血管结构重塑和血管新生是治疗门静脉高压症的重要目标。     

Propranolol reduces variceal pressure and wall tension in schistosomiasis presinusoidal portal hypertension

Background and Aim: Although prophylaxis with β‐blockers has been shown to decrease variceal pressure and wall tension in cirrhotic patients, this has not been demonstrated in non‐cirrhotic portal hypertension caused by Schistosoma mansoni infection. Methods: Thirteen patients without history of previous gastrointestinal bleeding were included. All of them had high‐risk esophageal varices at endoscopy. An endoscopic gauge and a high‐frequency endoscopic ultrasonography miniprobe were used to assess transmural variceal pressure and wall tension before and after achieving β‐blockade with propranolol. Results: Baseline variceal pressure decreased from 13.3 ± 3.5 to 8.2 ± 2.0 mmHg (P < 0.0001) and wall tension from 500.2 ± 279.8 to 274.0 ± 108.3 mg.mm^?1. The overall effect of propranolol on decreasing variceal pressure and wall tension expressed in percentage change in relation to baseline values was 35.7 ± 18.4% and 35.9 ± 26.7%, respectively (P = 0.9993). Conclusion: Propranolol significantly reduced variceal pressure and wall tension in schistosomiasis.     

Medical treatment of portal hypertension

In this chapter we give a quick review of the rationale for treatment of portal hypertension. The different scenarios for treatment of variceal bleeding will be discussed-that is, primary and secondary prophylaxis of variceal bleeding as well as the treatment of the acute bleeding episode. The role of the pharmacological, endoscopic and derivative treatments in each one of these scenarios will be discussed. Particular attention will be devoted to the potential role of the combination therapy of beta-blockers with isosorbide-5-mononitrate for preventing re-bleeding and to the best approach to patients with intolerance or contraindications to beta-blockers. We also give a rational review of the data comparing sclerotherapy against ligation as well as the potential role of the latter on primary prophylaxis.     

Captopril reduces portal pressure effectively in portal hypertensive patients with low portal venous velocity

Background The effect of an angiotensin II blockade in lowering the portal pressure in patients with liver cirrhosis and portal hypertension is controversial. This prospective study was undertaken to evaluate the portal hypotensive effect of captopril compared to that of propranolol, and to determine the factors that contribute to a successful reduction in the portal pressure after longterm captopril administration in patients with liver cirrhosis.Methods The hepatic venous pressure gradient (HVPG) and portal venous velocity (PVV) were measured both before and 3 months after initiation of the administration of captopril (n = 29) or propranolol (n = 29) in cirrhotic patients with a variceal bleeding episode. Patients who showed a reduction in the HVPG of more than 20% of the baseline were defined as being responders.Results At 3 months, the mean reduction in the HVPG after captopril was less than that after propranolol (–3.0 ± 9.3% vs –28.5% ± 4.1%; P 0.05). However, of the 29 patients receiving captopril, 9 were classified as being responders. On multivariate analysis with parameters including age, cause, Child-Pugh score, HVPG, and PVV, only low PVV was found to be a significant independent factor for responders (PVV 12cm/s; odds ratio [OR], 12.2; 95% confidence interval [CI], 1.47–102.40) in the captopril group.Conclusions Longterm captopril administration reduces the portal pressure effectively in cirrhotic patients with a low PVV. This suggests that the reduction in portal pressure after captopril administration is a result of improved portal venous outflow brought about by a decrease in the intrahepatic vascular resistance. When the PVV is below 12cm/s, a captopril trial might be useful in preventing variceal bleeding in portal hypertensive patients.Part of this work has appeared in abstract form, in J Hepatol 2002;36 (Suppl 1):64     

Nipradilol, a new β-blocker with vasodilatory properties, in experimental portal hypertension: A comparative haemodynamic study with propranolol

The haemodynamic effects of nipradilol, a new non-selective β-adrenoreceptor blocker with vasodilating actions like nitroglycerin, were examined in rats with portal hypertension due to portal vein stenosis. Portal hypertensive rats were divided into five groups receiving infusion of placebo, 3 mg of propranolol, 300, 600 and 1200 μg of nipradilol. At its highest dose, nipradilol achieved a reduction of 34.4 ± 4.4% in heart rate which was similar to that in the propranolol group (36.5 ± 2.4%). Also for other systemic haemodynamic parameters, the nipradilol 1200 μg group exhibited changes not significantly different from those in the propranolol group; mean arterial pressure (- 13 vs - 14%), cardiac index (- 37 vs - 31%) and systemic vascular resistance (+ 29 vs+ 32%). In contrast to the similar changes in the systemic circulation, a 1200 μg dose of nipradilol lowered portal pressure significantly more than propranolol (- 4.3 ± 0.6 vs - 2.9 ± 0.2 mmHg, P≤ 0.05). Nipradilol then reduced portal blood flow by 22% (P≤ 0.05) without a significant change in portocollateral resistance. On the other hand, propranolol not only caused a reduction in portal blood flow of 30% (P≤ 0.01), but also an increase in portocollateral resistance of 21% (P≤ 0.05). The results suggest that nipradilol may ensure a more effective control of portal hypertension than propranolol, presumably via its venodilatory action on portocollateral vessels.     

The free portal pressure in awake patients with and without cirrhosis of the liver

ABSTRACT— The free portal pressure was measured by percutaneous transhepatic catheterization of the portal vein in 106 patients with cirrhosis of the liver and in 19 patients without liver disease and with normal portography. Patients with cirrhosis had a median portal pressure of 38 cmH₂O and patients without liver disease had a median portal pressure of 16 cmH₂O. Among the cirrhotic patients the free portal pressure showed no relationship to etiology of cirrhosis, ascites, variceal bleedings or extrahepatic shunting. The median portal pressure was significantly higher in patients with (40 cmH₂O) than without (30 cmH₂O) gastroesophageal varices (p<0.01). The pressure was not related to the size of the varices.     

Indications for portal pressure measurement in chronic liver disease

Abstract

Portal hypertension leads to development of serious complications such as esophageal varices, ascites, renal and cardiovascular dysfunction. The importance of the degree of portal hypertension has been substantiated within recent years. Measurement of the portal pressure is simple and safe and the hepatic venous pressure gradient (HVPG) independently predicts survival and development of complications such as ascites, HCC and bleeding from esophageal varices. Moreover, measurements of HVPG can be used to guide pharmacotherapy for primary and secondary prophylaxis for variceal bleeding. Assessment of HVPG should therefore be considered as a part of the general characterization of patients with portal hypertension in departments assessing and treating this condition.     

泽泻对肝硬化门脉高压血流动力学影响的临床研究

为探讨泽泻对肝硬化门脉高压患者血流动力学影响,观察肝硬化患者在服用泽泻前后门静脉系统血流动力学的变化;记录用药前后不同时期患者尿量,并采集静脉血,利用生化及放免方法检测肾功能及血浆醛固酮水平。发现泽泻治疗10天后患者尿量显著增多(P<0.05),20天后门静脉血流量明显减少(P<0.05),而患者内生肌酐清除率、血浆醛固酮水平无明显差异。认为泽泻能有效减少门静脉血流量,降低门脉压力。对肾功能无影响,无毒副作用。     

Haemodynamic effects of a combination of propranolol and clonidine in patients with post-hepatitic cirrhosis

Abstract The haemodynamic effects of a combination of propranolol and clonidine were evaluated in 20 patients with post-hepatitic cirrhosis. Haemodynamic measurements were taken before and 30 min after an intravenous injection of 0.1 mg/kg of propranolol. Thereafter, each patient was given an oral dose of 150 μ g of clonidine and re-measured 60 min later. In this series, eight patients were defined as 'non-responders' (a decrease in hepatic venous pressure gradient of < 10%) after propranolol treatment. Of both the responders and non-responders, propranolol caused expected decreases in the cardiac index and heart rate while mean arterial pressure remained unchanged. Of the propranolol responders, a significant decrease in hepatic venous pressure gradient was observed. After the addition of clonidine, in both the responders and non-responders there was a further decrease in hepatic venous pressure gradient with a concurrent drop in mean arterial pressure, but cardiac index and heart rate remained unaltered. In conclusion, the combination of propranolol and clonidine in post-hepatitic cirrhotic patients enhanced the reduction of portal pressure achieved by propranolol alone. The beneficial effects of the combination of the two in the reduction of portal pressure appeared to be similar in both the propranolol responders and non-responders. However, the drop in mean arterial pressure following the addition of clonidine may be hazardous to cirrhotic patients.     

Duplex-Doppler ultrasonography in the evaluation of cirrhotic patients with portal hypertension and in the analysis of their response to drugs

Sixteen patients (15 males, aged 48-70) affected by liver cirrhosis and oesophageal varices were subjected to duplex-Doppler ultrasonographic study (DDUS). Four patients (three with a portal thrombosis and one with a hepatofugal portal flow) were excluded from the subsequent pharmacological test. The twelve remaining patients took part in a double blind cross-over study that evaluated the variations of heart rate (HR), mean systemic arterial pressure (SAP), portal vein diameter (PVD), maximal and mean portal flow velocity (PFV) after the administration of either 40 mg of propranolol or placebo per os, on two consecutive days. Propranolol caused no significant variation in mean SAP and in PVD, whereas it reduced the HR from 67.7 +/- 8.0 to 58.4 +/- 7.0 beats/min (mean +/- s.d.; P less than 0.001); the maxPFV dropped from 18.2 +/- 5.4 to 14.0 +/- 3.7 cm/s (P less than 0.001) and the meanPFV dropped from 15.3 +/- 4.1 to 13.2 +/- 3.1 cm/s (P less than 0.005). No significant variation was observed with placebo. After propranolol administration eight patients exhibited a significant maxPFV decrease, whereas the other four patients exhibited only a drop in HR, suggesting either drug inefficacy, inappropriate dosage or inadequate duration of treatment. DDUS is the only non-invasive method for the examination of the portal vein system.(ABSTRACT TRUNCATED AT 250 WORDS)     

Underlying mechanism of portal hypertensive gastropathy in cirrhosis: A hemodynamic and morphological approach

Background and Aim:  Portal hypertensive gastropathy (PHG) is an important cause of bleeding in patients with cirrhosis associated with portal hypertension. Histologically, the condition is characterized by dilation of the mucosal and submucosal vessels of the stomach; however, its mechanisms remain unclear. The aim of the present cross-sectional study was to evaluate the role of portal and systemic hemodynamic features, humoral factors and hepatocellular function in the development and severity of PHG in patients with cirrhosis.
Methods:  Forty-six patients with cirrhosis of different etiologies underwent endoscopy. Portal hypertension was evaluated by hepatic venous pressure gradient (HVPG). The gastric mucosa was analyzed using two diagnostic methods: endoscopy according to the McCormack criteria and histological by histomorphometric analysis.
Results:  The prevalence of PHG according to the endoscopic and histomorphometric methods was 93.4% and 76.1%, respectively. There were no statistically significant differences in HVPG measurements between the patients with mild (16.0 ± 5.9 mmHg) and severe PHG (16.9 ± 6.5 mmHg; P  = 0.80) or between patients who did not have (15.2 ± 8.0 mmHg) and those who had PHG (16.3 ± 5.7 mmHg). No correlation was found between the presence or severity of PHG and systemic vascular resistance index ( P  = 0.53 and 0.34, respectively), Child–Pugh classification ( P  = 0.73 and 0.78, respectively) or glucagon levels ( P  = 0.59 and 0.62, respectively).
Conclusions:  The present data show no correlation between the presence or the severity of PHG and portal pressure, Child–Pugh classification or systemic hemodynamics, suggesting that other factors may be involved in the physiopathology of PHG, such as local gastric mucosal factors or other underlying factors.     

Effects of somatostatin on splanchnic hemodynamics in cirrhotic patients with portal hypertension

INTRODUCTION Esophageal variceal bleeding (EVB) is one of the most common complications of cirrhosis with portal hypertension. In recent years, great progress has been made in medicinal treatment. Somatostatin has been widely used in clinics, for it can effectively lower the portal venous pressure (PVP) with little side effect. The aim of this study is to assess the effect of somatostatin on portal venous pressue and splanchnic hemodynamics in patients with liver cirrhosis and portal hypertension.     

Comparison of the hemodynamic effects of metoprolol and carvedilol in hypertensive patients

Summary Metoprolol and carvedilol are widely used in the treatment of hypertension, but no randomized comparison of their hemodynamic activity has been previously reported. Their comparative effects on heart rate, systemic blood pressure, and echocardiographically determined aortic and femoral artery blood flow were measured at rest and at 2 and 24 hours after the first dose of each drug, and again after 4 weeks of sustained monotherapy in 12 male and 12 female patients, aged 36–68 years with uncomplicated sustained hypertension according to a randomized single-blind protocol. Nine patients in each drug group achieved the target diastolic blood pressure of <90 mmHg on the initial doses of each drug; this was achieved in the remainder following doubling of each dose. Neither drug occasioned withdrawal of any patient due to adverse reactions. Both drugs significantly reduced heart rate, although the reduction at 2 hours was significantly greater after metoprolol than after carvedilol. Both drugs reducd systolic pressure throughout the study; the reduction at 2 hours was significantly greater after carvedilol than after metoprolol. In contrast, the diastolic blood pressure was persistently reduced only by carvedilol. The cardiac output, determined as the aortic systolic blood flow, after carvedilol was not significantly different from pretreatment values throughout the study but was significantly reduced in the metoprolol-treated patients at each point of measurement. After metoprolol the systemic and femoral vascular resistances derived from conventional formulae were consistently and significantly increased over pretreatment values throughout the study and were significantly greater than in the carvedilol group at all measurement points. The hemodynamic differences between these two beta-blocking drugs may be explained by the additional vasodilator activity of carvedilol associated with its alpha₁-adrenoceptor blocking activity. The long-term clinical and prognostic implications of these pharmacodynamic differences between beta-adrenoceptor antagonists with and without additional vasodilator activity in the treatment of hypertensive patients remain to be determined.     

Systemic and splanchnic hemodynamics following hemorrhage and volume restitution with Haemaccel in portal hypertensive rats: The effect of propranolol

BACKGROUND AND AIMS: Recently, we found in a portal hypertensive rat model that hemorrhage and volume restitution with Haemaccel, a low viscosity plasma expander, induced an increase in cardiac output and portal venous inflow. The present study was conducted to evaluate whether pretreatment with propranolol will attenuate these hyperdynamic changes. METHODS: Portal hypertension was induced by portal vein constriction. Treatment was initiated 14--21 days later. Propranolol (30 mg/kg per day) or water were administered for 7 days via a gastric gavage. Under ketamine anesthesia, 18 h after the last given dose, blood was withdrawn at a constant rate of 0.3 mL/min for 15 min followed by a 15-min stabilization. Haemaccel was infused at the same rate and volume used for withdrawal. Hemodynamic measurements were performed after volume restitution in both groups by using radioactive microspheres. RESULTS: Eight rats were studied in each group. In the propranolol-treated animals, portal venous inflow was decreased (2.4 +/- 0.8 vs 3.8 +/- 0.7 mL/min per 100 g bodyweight; P < 0.01), while splanchnic arteriolar and porto-collateral resistance were increased (52.8 +/- 21.0 vs 32.8 +/- 13.0 and 6.0 +/- 1.4 vs 4.1 +/- 0.7 mmHg x min x 100 g bodyweight/mL; P < 0.05, respectively). Cardiac output, mean arterial pressure, heart rate, total peripheral resistance and portal pressure were not significantly different between the two groups. CONCLUSION: In this model, pretreatment with propranolol prevented the increase in portal venous inflow, which occurs following hemorrhage and volume restitution with Haemaccel. Although caution should be taken in extrapolating data from animal models to humans, our results suggest that volume replacement during a portal hypertensive-related bleeding episode may be safer in a patient treated with non-selective beta-adrenoreceptor antagonists.