Hemodynamic study during transdermal application of nitroglycerin tape in patients with cirrhosis

We studied 14 patients with portal hypertension and cirrhosis using portal and hepatic vein catheterizations to determine the effects of transdermal application of nitroglycerin tape (containing 10 mg of nitroglycerin and capable of releasing 6 to 7 mg of nitroglycerin in 12 hr) on splanchnic hemodynamics. Patients randomly received nitroglycerin (n = 7) or a placebo (n = 7). No significant changes were observed after the administration of the placebo. In contrast, transdermal nitroglycerin caused a significant reduction in portal pressure, as evaluated by measurements of the portal venous pressure gradient (-22%, p less than 0.01). The reduction of portal pressure was due to a decrease in the portal venous pressure, with no changes in the free hepatic venous pressure. Despite the fall in portal pressure, the hepatic blood flow was maintained. These findings suggest that transdermal nitroglycerin could be potentially useful in the treatment of portal hypertension associated with cirrhosis.     

Nitroglycerin improves the hemodynamic response to vasopressin in portal hypertension

This study was designed to investigate whether the addition of nitroglycerin to vasopressin infusion could avoid the deleterious systemic effects of vasopressin while maintaining or enhancing the therapeutic benefits of portal pressure reduction. The effect of nitroglycerin on splanchnic and systemic hemodynamics was studied in cirrhotic patients and portal hypertensive dogs receiving i.v. vasopressin. During i.v vasopressin infusion (0.4 units per min), the cardiac output decreased in patients by 14% from 7.6 +/- 0.9 (mean +/- S.E.) to 6.5 +/- 0.7 liters per min, p less than 0.01, the mean arterial pressure increased 21% from 87 +/- 2 to 105 +/- 4, p less than 0.01, and the heart rate decreased 11% from 79 +/- 3 to 71 +/- 3, p less than 0.01. The administration of sublingual nitroglycerin (0.4 mg) returned all the systemic hemodynamic parameters to baseline values. In dogs, vasopressin infusion significantly reduced portal pressure and flow while increasing portal venous resistance. Nitroglycerin when added to the vasopressin infusion reduced portal venous resistance and further decreased portal pressure in dogs. In patients, vasopressin reduced the hepatic blood flow (44%), wedged hepatic venous pressure (11%), and the gradient between wedged and free hepatic venous pressures (23%). Nitroglycerin administration caused a further reduction of the wedged hepatic venous pressure (23.6 +/- 2.3 to 21.1 +/- 2.0, 11%, p less than 0.01). There was a small but not significant further decline (7%) in the hepatic venous pressure gradient. These results provide evidence that the addition of nitroglycerin to an i.v. infusion of vasopressin reversed the detrimental effects of vasopressin while preserving the beneficial effects.     

Portohepatic Pressures, Hepatic Function, and Blood Gases in the Combination of Nitroglycerin and Vasopressin: Search for Additive Effects in Cirrhotic Portal Hypertension

We studied the effects of the combination of nitroglycerin and vasopressin on portohepatic hemodynamics, hepatic function, and blood gases in nine patients with cirrhosis and portal hypertension. Vasopressin infusion at a dose of 0.4 U/min caused a significant fall in portal pressure, which is evaluated by portal venous pressure gradient (-34%, p less than 0.01), associated with a decrease in hepatic perfusion (-33%, p less than 0.01) and intrinsic clearance (-20%, p less than 0.01) after 30 min. The arterial oxygenation, however, was not modified (paO2; from 73 +/- 8 to 72 +/- 7 mm Hg, NS). Nitroglycerin infusion at a dose of 100 micrograms/min was then administered for 20 min. The addition of nitroglycerin produced a further reduction in free portal venous pressure (-12%, p less than 0.01), but this was not associated with a significant improvement in both hepatic perfusion (+16%, NS) and intrinsic clearance (-7%, NS). In addition, there was a significant fall in arterial oxygenation (paO2; from 72 +/- 7 to 59 +/- 5 mm Hg, p less than 0.01). We conclude that the addition of nitroglycerin to vasopressin has a beneficial effect on free portal venous pressure, but does not have hepatic benefit. Moreover, sufficient care must be taken, when treating portal hypertension with this combination, to avoid arterial hypoxemia.     

Portal hemodynamics during nitroglycerin administration in cirrhotic patients

Nitroglycerin is a potent venous dilator and a mild arterial vasodilator that has been shown to improve the hemodynamic response to vasopressin in portal hypertensive patients and to decrease portal pressure in experimental animals. In order to determine the effect of nitroglycerin on portal venous hemodynamics, we studied 11 patients with alcoholic cirrhosis before and during the administration of sublingual nitroglycerin (0.4 and 0.6 mg). The hepatic venous pressure gradient (which was obtained by subtracting the free hepatic venous pressure from the wedged hepatic venous pressure) decreased from 17.9 +/- 6.5 mm Hg (mean +/- S.D.) to 15.1 +/- 5.1 mm Hg (p less than 0.02) at the peak of the effect, which occurred from 2 to 12 min after nitroglycerin administration. The mean arterial pressure was reduced from 96 +/- 10 mm Hg to a peak decrease of 76 +/- 18 mmHg (p less than 0.001). The peak change in the hepatic venous pressure gradient induced by nitroglycerin correlated directly with the peak change in mean arterial pressure (r = 0.79, p less than 0.01). There was a moderate increase in heart rate in response to the decrease in blood pressure (73 +/- 15 to 83 +/- 15 beats per min, p less than 0.001). Two of the 11 patients did not reduce their hepatic venous pressure gradient after 0.6 mg nitroglycerin. Reductions in portal pressure were observed with both increases and moderate decreases in azygos blood flow, suggesting that, as observed in experimental animals, the portal-pressure-reducing effect of nitroglycerin could be due to two different and independent mechanisms, a reduction in portal blood flow or portal-collateral vasodilatation.     

Effects of vaso-active agents on hepatic function and blood gases in patients with cirrhosis: A study of vasopressin and nitroglycerin

The effects of vaso-active agents on hepatic function and splanchnic oxygenation were studied in 17 patients with cirrhosis and portal hypertension. Eight patients received vasopressin (0.3 iu/min) and nine patients received nitroglycerin (50 micrograms/min). Both drugs caused a significant reduction in the portal venous pressure gradient. Vasopressin infusion significantly decreased intrinsic clearance of indocyanine green (-23%, P less than 0.01). This may be due to a decreased hepatic perfusion (-28%, P less than 0.01) and portal venous oxygenation (-15% in portal venous oxygen tension, P less than 0.05). In contrast, no changes in hepatic perfusion and portal venous oxygenation were observed after nitroglycerin infusion. Nitroglycerin did not decrease intrinsic clearance of indocyanine green. These results suggest that vasodilators, rather than vasoconstrictors, might be welcome in the treatment of patients with cirrhosis and portal hypertension.     

Effects of Propranolol on Portal Hemodynamics in Patients with Chronic Liver Disease

To elucidate the mechanism by which propranolol reportedly affects portal hemodynamics, we investigated the effect of propranolol on systemic and splanchnic hemodynamics in 15 patients with portal hypertension and esophageal varices by simultaneous catheterization of the portal vein and the right hepatic vein and measurement of portal venous flow using an ultrasound doppler system. Infusion of 5 mg of propranolol significantly decreased pulse rate (-12.6%), cardiac output (-24.5%), portal venous flow (-22.3%), portal venous pressure (-13.3%), and gradient between portal venous pressure and free hepatic venous pressure (-24.8%). Thus, propranolol seems to decrease portal venous pressure by reducing portal venous flow, at least in part, as a result of reduction of cardiac output due to its beta 1 adrenergic receptor blocking action.     

Systemic and portal haemodynamic changes following triglycyllysine vasopressin plus nitroglycerin administration in patients with hepatitis B-related cirrhosis

We measured the haemodynamic changes following triglycyllysine vasopressin administration and after addition of nitroglycerin in twelve patients with portal hypertension due to hepatitis B-related cirrhosis. A bolus i.v. injection of triglycyllysine vasopressin at a dose of 2 mg reduced the hepatic venous pressure gradient from 18.5 +/- 3.7 (mean +/- S.D.) to 15.6 +/- 4.0 mmHg, p less than 0.001. However, the cardiac index decreased from 4.8 +/- 1.0 to 3.7 +/- 0.8 l/min m2, p less than 0.001; the heart rate decreased from 79 +/- 15 to 71 +/- 13, p less than 0.01; the right atrial pressure increased from 3.2 +/- 1.9 to 5.3 +/- 2.3 mmHg, p less than 0.001; the mean arterial pressure increased from 92 +/- 13 to 103 +/- 13 mmHg, p less than 0.05; and the systemic vascular resistance rose from 939 +/- 182 to 1367 +/- 310 dyn/s cm-5, p less than 0.001. Furthermore, both mean pulmonary arterial pressure and pulmonary capillary wedge pressure showed a significant increase following triglycyllysine vasopressin administration as compared with baseline values (p less than 0.005). The addition of sublingual nitroglycerin at a dose of 0.6 mg returned all the systemic haemodynamic parameters to baseline levels. On the other hand, nitroglycerin administration caused no further change in the hepatic venous pressure gradient. We concluded that although triglycyllysine vasopressin significantly reduced portal pressure in patients with hepatitis B-related cirrhosis, it produced untoward systemic haemodynamic changes similar to those seen with vasopressin. The addition of nitroglycerin improved the detrimental systemic haemodynamic effects produced by triglycyllysine vasopressin without further reducing the hepatic venous pressure gradient.     

Low dose of nitroglycerin failed to improve splanchnic hemodynamics in patients with cirrhosis: evidence for an impaired cardiopulmonary baroreflex function

High doses of nitroglycerin may decrease portal pressure in patients with cirrhosis with untoward effects such as arterial hypotension and a decrease in systemic O2 uptake. In the present study, low doses of nitroglycerin (7 to 15 micrograms per min, i.v.) were administered in 11 patients with cirrhosis in order to unload cardiopulmonary baroreceptor--one of the possible mechanisms by which nitroglycerin may improve splanchnic hemodynamics--and moreover to avoid deleterious systemic effects. Nitroglycerin significantly decreased right atrial pressure (-35%) and pulmonary wedged pressure (-27%) with significant increase in plasma norepinephrine concentration (+23%), which indicated that cardiopulmonary baroreceptor unloading was achieved. Changes in systemic hemodynamics were slight, although significant, with a decrease in arterial pressure (-8%) and an increase in heart rate (+8%); this indicates a minimal effect on high-pressure baroreflexes. In contrast, no significant change was observed in hepatic venous pressure gradient, hepatic blood flow and azygos blood flow. However, the fraction of cardiac output reaching the azygos system significantly increased by 18%. Plasma renin activity did not change significantly. Moreover, O2 transport and uptake were significantly decreased. These findings show that low doses of nitroglycerin failed to improve splanchnic hemodynamics in patients with cirrhosis. These results suggest an impaired cardiopulmonary baroreflex function which is probably located on the efferent arch.     

Effects of Vasopressin on Portal Hemodynamics in Patients with Portal Hypertension

In view of the variability in the magnitude of the response of portal venous pressure to vasopressin in man, we investigated the effect of vasopressin on portal hemodynamics in seven patients with portal hypertension by simultaneous catheterization of the portal and the hepatic vein and the measurement of portal venous flow by an echo-Doppler flowmetry. Infusion of vasopressin (0.3 U/min) significantly decreased portal venous pressure (-36%), the gradient between portal venous pressure and free hepatic venous pressure (-50.6%), and portal venous flow (-54.3%) but did not reduce mean arterial pressure and pulse rate. Thus, vasopressin seems to decrease portal venous pressure by reducing portal venous flow.     

Effects of molsidomine, a long acting venous dilator, on portal hypertension. A hemodynamic study in patients with cirrhosis.

The present study investigated the effects of molsidomine, a predominant venous dilator which, contrary to organic nitrates, does not produce pharmacological tolerance on splanchnic and systemic hemodynamics in patients with cirrhosis. Twenty-seven cirrhotic portal hypertensive patients were studied prior to and up to 2 h after the oral administration of 2 mg of molsidomine (n = 11), 4 mg of molsidomine (n = 8) or placebo (n = 8). Molsidomine caused a significant reduction in the hepatic venous pressure gradient. The mean decrease at 60 min was -6.8 +/- 9% after 2 mg (p less than 0.05) and -15.4 +/- 12% after 4 mg (p less than 0.01). The decrease in the hepatic venous pressure gradient was maintained at 120 min: -11% after 2 mg (p less than 0.05) and -19% with 4 mg (p less than 0.01). This was associated with mild changes in azygos blood flow and with a significant decrease in hepatic blood flow (-17%, p less than 0.05). There was a moderate reduction in mean arterial pressure (-12.6% after 2 mg and -13.2% after 4 mg, p less than 0.01), which was due to a reduction in cardiac output, without any significant fall in systemic vascular resistance. Placebo administration did not change systemic or hepatic hemodynamics. This study shows that molsidomine causes a significant and sustained reduction in portal pressure in patients with cirrhosis, suggesting the potential role of this agent in the treatment of portal hypertension.     

Nitroglycerin for portal hypertension. A controlled comparison of the hemodynamic effects of graded doses

Nitroglycerin is reportedly an effective treatment for portal hypertension. However, the effects of graded doses have not been examined. We administered nitroglycerin intravenously to 10 patients with alcoholic cirrhosis, beginning at 10 micrograms/min and doubling the dose every 10 min thereafter until mean arterial pressure fell 10-15 mmHg. We compared the response to that of 10 patients receiving a control infusion. The median infusion rate of nitroglycerin was 40 micrograms/min (range 10-160 micrograms/min). Nitroglycerin significantly reduced cardiac output as well as pulmonary artery, pulmonary capillary and mean arterial pressure. The overall effects of nitroglycerin on the hepatic venous pressure gradient and azygous (gastroesophageal collateral) blood flow were heterogeneous. However, the hepatic venous pressure gradient significantly increased in nitroglycerin-treated patients with high pulmonary capillary pressures (greater than or equal to 12 mmHg) compared to control patients with similar cardiac filling pressures at both median and maximum rates of infusion. Nitroglycerin is therefore not a uniformly effective treatment for portal hypertension. Cardiac filling pressure may be a determinant of the splanchnic hemodynamic response to nitroglycerin.     

The hemodynamic effect of verapamil on portal hypertension in patients with postnecrotic cirrhosis

Wedged hepatic venous pressure, free hepatic venous pressure and cardiac index were measured before and 1 hr after i.v. administration as well as 1 month and 3 months after chronic oral administration of verapamil in 10 patients with HBsAg-positive cirrhosis. The gradient between wedged hepatic venous pressure and free hepatic venous pressure was decreased 14% at 1 hr after i.v. administration of 10 mg verapamil, and the sustained decrease in hepatic venous pressure gradient was also demonstrated in the patients after 1 month, and in six patients after 3 months of continuous oral administration of verapamil. The mean arterial pressure significantly decreased (p less than 0.01) 1 hr after the administration of verapamil. There was no significant change in other hemodynamic values. We conclude that chronic oral administration of verapamil can reduce the hepatic venous pressure gradient in patients with compensated HBsAg-positive cirrhosis and portal hypertension.     

Hemodynamic effects of the administration of terlipressin alone or combined with nitroglycerin in patients with cirrhosis]

Terlipressin (Glypressin), a synthetic analog of vasopressin, induces arteriolar vasoconstriction which causes both a portal hypotensive effect and certain side-effects on the systemic circulation (elevated arterial pressure and reduced cardiac output). The combination of nitroglycerin with terlipressin might accentuate the portal hypotensive effect and prevent the side-effects on the systemic circulation. The aim of this study was to examine the systemic and splanchnic hemodynamic responses to terlipressin administered alone or combined with nitroglycerin in patients with cirrhosis. Systemic and splanchnic hemodynamics were measured before and 1 h after a bolus of terlipressin (1 to 2 mg IV) given alone (n = 10) or in association with nitroglycerin infusion (25 micrograms/min, n = 9). Terlipressin alone significantly increased the arterial pressure by 21%, systemic vascular resistance by 60%, and significantly decreased cardiac output by 23%. The right atrial and pulmonary pressures significantly increased and the wedged hepatic venous pressure and hepatic venous pressure gradient significantly decreased by 8% and 16%, respectively. The combined therapy decreased the cardiac output by 20%, but did not significantly modify the other systemic and splanchnic hemodynamic values. No significant differences were found between terlipressin and the combined therapy concerning changes in wedged hepatic venous pressure or hepatic venous pressure gradient. We conclude that in patients with cirrhosis, nitroglycerin prevents the deleterious vasoconstrictor and vasopressor effects of terlipressin. However, the combined therapy, as terlipressin alone, decreases the cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of propranolol on hepatic and systemic hemodynamics in dogs with chronic bile duct ligation

Propranolol has been reported to reduce portal and wedged hepatic vein pressures in man and may be useful for the prevention of variceal bleeding. However, its mechanism of action remains unclear. We have examined the effect of propranolol on the systemic and hepatic circulations in dogs with chronic bile duct ligation and secondary biliary cirrhosis. Under anesthesia, eight dogs received four increasing doses of propranolol as an i.v. bolus followed by continuous infusion. Systemic and hepatic hemodynamic parameters were measured in basal conditions and after a 30 min infusion for each dose. Portal vein and hepatic artery blood flows were measured with electromagnetic flow meters. All dogs had portal hypertension (portal venous pressure 15.3 +/- 0.8 mm Hg), a hyperdynamic circulation and severe liver disease resulting in a marked decrease of propranolol systemic clearance (8.75 ml per min per kg) and extraction (40%). The first dose of propranolol induced a decrease in heart rate (-27%) and in cardiac index (-21%), and an increase in systemic vascular resistance (+20%). With increasing doses, the systemic vascular resistance decreased with an increase in the cardiac index. Propranolol was not associated with significant modifications of hepatic hemodynamics: portal, wedged and free hepatic venous pressures and hepatic artery blood flow were stable, and portal blood flow decreased slightly at very high propranolol levels. In seven dogs studied without dissection of the hepatic vessels, there was a small decrease in portal pressure, but not in wedged and free hepatic venous pressures with increasing doses of propranolol. Thus, in dogs with intrahepatic portal hypertension, propranolol has significant effects on systemic hemodynamics, but only minimal effects on the hepatic circulation.     

Oral Administration of Nipradilol and the Acute and Chronic Splanchnic Hemodynamic Effects of a New β-Blocker with Nitrovasodilating Properties in Patients with Liver Cirrhosis

Objectives: We studied the effects of nipradilol, which has both a nonselective β-blocker action and a vasodilating action similar to nitroglycerin, on portal hypertension. Methods: We measured hepatic venous pressure gradient and splanchnic and systemic hemodynamics before beginning therapy, 2 h after an oral dose of 6 mg, and after either 6 months of nipradilol 6 mg twice a day (n = 14) or of a placebo (n = 6) in 20 cirrbotic patients. Results: No significant changes were observed after the administration of the placebo. Oral nipradilol induced a significant reduction in the hepatic venous pressure gradient (base line: 14.8 ± 3.2 mm Hg vs 2 h: 12.3 ± 3.4 mm Hg, p < 0.01; 6 mo: 12.5 ± 3.2 mm Hg, p < 0.05) without a significant change in the free hepatic venous pressure. The hepatic vascular resistance decreased signifi-cantly (base line: 1811 ± 778 dyn. sec. cm^-5 vs 2 h: 1540 ± 701 dyn. scc. cm^-5, p < 0.05; 6 mo: 1564 ± 693 dyn. sec. cm^-5, p < 0.05) without a significant change in hepatic blood flow. A decrease in the hepatic venous pressure gradient greater than 10% was observed in nine patients (64%), defined as "responders," at 2 h and in 10 patients (71%) at 6 months. The reduction of mean heart rate and hepatic venous pressure gradient in these responders was 16.2% and 28.3% at 2 h and 15.1% and 27.1% at 6 months, respectively. Conclusions: We found that in some cirrhotic patients, at the doses used in this study, long term oral nipradilol administration produces a reduction in the hepatic venous pressure gradient with both a β-blocking and a nitrovasodilating action.     

The portal pressure response to beta-blockade is greater in cirrhotic patients without varices than in those with varices

BACKGROUND & AIMS: Nonselective beta-blockers are effective in reducing portal pressure in cirrhotic patients. However, this beneficial effect is highly variable and may depend on the extent of portal system collateralization. The aim of this study was to compare portal pressure response with timolol, a nonselective beta-blocker, in cirrhotic patients with and without varices. METHODS: Portal and systemic hemodynamics were measured before and after a single oral dose of 10 mg of timolol in 50 patients with cirrhosis and portal hypertension, 15 with and 35 without esophageal varices. RESULTS: Timolol significantly decreased portal pressure in all patients (mean reduction, 20% +/- 13%; P < 0.0001). The reduction in hepatic venous pressure gradient was greater in patients without varices (-24% +/- 14%) than in those with varices (-12% +/- 8%) (P < 0.01). A decrease in the hepatic venous pressure gradient of <12 mm Hg was achieved in 7 of 12 (58%) patients without varices and a baseline pressure gradient of <12 mm Hg, but only in 3 of 15 patients with varices (20%) (P < 0.01). CONCLUSIONS: Timolol is effective in reducing portal pressure in cirrhotic patients, more so in patients without varices, suggesting that nonselective beta-blockers will be more effective in the treatment of portal hypertension when administered at early stages, before the development of varices. (Gastroenterology 1997 Jun;112(6):2012-6)     

Comparison between portal vein pressure and wedged hepatic vein pressure in hepatitis B-related cirrhosis

Portal vein pressure and wedged hepatic vein pressure were measured simultaneously in 21 patients with hepatitis B-related cirrhosis of the liver and were compared to pressure measured in six patients with idiopathic portal hypertension. No significant difference in the portal venous pressure gradient was found between patients with cirrhosis and those with idiopathic portal hypertension (17.3 +/- 4.3 mmHg (mean +/- S.D.) vs. 19.7 +/- 3.1 mmHg, P greater than 0.05). However, the difference between the portal and the hepatic venous pressure gradient was significantly smaller in patients with cirrhosis than in idiopathic portal hypertension patients (1.3 +/- 1.7 vs. 10.8 +/- 2.1 mmHg, P less than 0.001). An excellent correlation was found between portal vein pressure and wedged hepatic vein pressure in hepatitis B-related cirrhosis (r = 0.94, P less than 0.001). There was no linear relationship between the portal venous pressure gradient and varix size or bleeding episodes. We concluded that a close agreement existed between portal vein pressure and wedged hepatic vein pressure in hepatitis B-related liver cirrhosis. Therefore, measurement of wedged hepatic vein pressure reliably reflects portal vein pressure in these patients.     

Systemic and splanchnic hemodynamic effects of molsidomine in rats with carbon tetrachloride-induced cirrhosis

Molsidomine, a long-acting vasodilator mainly used as an antianginal agent, was reported to decrease the portohepatic venous pressure gradient in patients with alcoholic cirrhosis. This study investigated the effects of linsidomine, the active metabolite of molsidomine, on systemic and splanchnic hemodynamics in rats with CCl4-induced cirrhosis using the microsphere technique. Compared with placebo-treated rats, linsidomine-treated animals were found to have a significant decrease in portal venous pressure (-18%, p less than 0.01) and in mean arterial pressure (-16%, p less than 0.01), smaller peripheral resistances (p less than 0.01), greater portal venous inflow (p less than 0.05), smaller splanchnic arteriolar resistances (p less than 0.01) and smaller protocol-lateral resistances (p less than 0.05). Cardiac output, hepatic arterial blood flow, portal blood flow and estimated hepatic blood flow were not significantly different between the two groups of animals. Linsidomine-treated rats exhibited a trend toward greater collateral blood flow compared with controls, but this difference was not significant. We conclude that linsidomine decreases portal venous pressure by reducing portocollateral resistances without affecting liver blood flow. These effects should be beneficial for patients with cirrhosis and portal hypertension.     

Hepatic arterial pulsatility index in cirrhosis: correlation with portal pressure.

BACKGROUND/AIMS: Determination of the pulsatility index by means of duplex sonography provides the opportunity to evaluate the vascular resistance of the hepatic artery noninvasively. The aim of this study was to investigate the relationship between the hepatic arterial pulsatility index and the hepatic venous pressure gradient in cirrhosis. METHODS: In 50 patients with cirrhosis, hepatic venous pressure gradient was determined in the fasting state. Immediately thereafter, hepatic arterial pulsatility index and portal blood flow velocity were measured by duplex sonography with no knowledge of hepatic venous pressure values. In addition, the duplex parameters were determined in 20 controls. RESULTS: Hepatic arterial pulsatility index was significantly higher in patients with cirrhosis than in controls (0.92+/-0.1 vs. 1.14+/-0.18; p<0.001) and directly correlated with the hepatic venous pressure gradient (r = 0.7; p<0.001). Furthermore, weak correlations were found between hepatic arterial pulsatility index and Child-Pugh score (r = 0.49; p<0.01) and between portal blood flow velocity and hepatic venous pressure gradient (r = -0.48; p<0.01). CONCLUSION: In cirrhosis the hepatic arterial vascular resistance seems to increase parallel to the rise of the portal pressure. Therefore, duplex sonographic determination of the hepatic arterial pulsatility index may contribute to the noninvasive evaluation of portal hypertension.     

Long-term haemodynamic effects of isosorbide 5-mononitrate in patients with cirrhosis and portal hypertension

Since it is well known that pharmacological tolerance may rapidly occur on continuous administration of organic nitrates, in this study we attempted to investigate whether isosorbide 5-mononitrate (Is-5-Mn), a long-acting vasodilator that decreases portal pressure in acute haemodynamic studies, causes a significant reduction in portal pressure following long-term oral administration. Eleven patients with cirrhosis and portal hypertension were studied prior to and following 3 months of continuous administration of Is-5-Mn, 40 mg b.i.d. The hepatic venous pressure gradient decreased significantly following long-term Is-5-Mn treatment (from 18.6 +/- 3.4 to 17.2 +/- 3.1 mmHg; p less than 0.01). This was associated with a moderate increase in hepatic blood flow. Azygos blood flow and portal blood flow did not change. There were significant decreases in mean arterial pressure (from 89.4 +/- 13.7 to 82.6 +/- 10.8 mmHg; p less than 0.05) and heart rate (from 77 +/- 10 to 73 +/- 10 b.p.m.; p less than 0.05). In contrast, there were no changes in portal pressure or hepatic and systemic haemodynamics in a control group of 17 patients receiving placebo. Repeated nitroglycerin cross-tolerance studies in five patients receiving Is-5-Mn indicated the development of a partial pharmacological tolerance (as shown by blunted haemodynamic response to nitroglycerin after long-term Is-5-Mn administration). This study shows that Is-5-Mn continues to cause a significant decrease in portal pressure during long-term therapy, with only partial pharmacological tolerance to this compound.