Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the underlying mechanisms no doubt differ, activation of the sympathetic nervous system is an important pathophysiological feature in primary arterial hypertension, in portal hypertension accompanying hepatic cirrhosis, and in heart failure, and is a logical therapeutic target for centrally acting sympathetic nervous system suppressant drugs. Portal hypertension: The sympathetic outflows to skeletal muscle vasculature, the heart, the kidneys and to the hepatomesenteric circulation are stimulated in patients with alcoholic cirrhosis of the liver, perhaps as a reflex response to the vasodilatation and vascular shunting present. Acute dosing with clonidine produces dose dependent reduction in noradrenaline spillover from visceral organs and reduction in hepatic vein wedge pressure, with preservation of hepatic blood flow and negligible fall in arterial pressure. These findings indicate the clinical potential of drugs such as clonidine, moxonidine and rilmenidine for chronically lowering portal venous pressure in cirrhosis. Arterial hypertension: Activation of the sympathetic outflow to the heart, kidneys and skeletal muscle vasculature is commonly present in younger (< 45 years) patients with essential hypertension. The sympathetic stimulation appears to have adverse consequences in hypertensive patients beyond blood pressure elevation. Neural vasoconstriction in skeletal muscle has metabolic effects by impairing glucose delivery, which is a basis for insulin resistance and hyperinsulinemia. Within the heart a trophic effect of sympathetic activation on cardiac growth, contributing to the development of left ventricular hypertrophy, and an arrhythmogenic effect are also likely. Cardiac failure: The cardiac sympathetic nerves are preferentially stimulated in severe heart failure, with norepinephrine release from the failing heart at rest being increased as much as 50-fold, similar to the level seen in healthy people during near maximum exercise. This preferential activation of the cardiac sympathetic outflow contributes to arrhythmogenesis and possibly to progression of the heart failure, and has been directly linked to mortality; a high rate of spillover of noradrenaline from the heart is a strong, independent predictor of poor prognosis in severe cardiac failure. The mechanisms underlying sympathetic nervous stimulation are not entirely clear. Increased intracardiac diastolic pressure seems to be one peripheral signal, and increased forebrain norepinephrine turnover an important central mechanism. Following the demonstration of the beneficial effect of the beta-adrenergic blocker, carvedilol, and with second generation centrally acting sympathetic suppressants now under clinical investigation, elucidation of the abnormalities in central nervous control of sympathetic outflow in heart failure has become clinically relevant.
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PMID:Increased sympathetic nervous system activity and its therapeutic reduction in arterial hypertension, portal hypertension and heart failure. 985 71

Profound thrombocytopenia resulting from portal hypertension may exacerbate gastrointestinal bleeding, precipitate spontaneous bleeding, preclude surgical intervention for associated disorders, and severely limit life-style because of the danger of splenic injury. Although splenectomy can reverse the thrombocytopenia, the procedure should be avoided in children. We reviewed our experience with distal splenorenal shunting (DSRS) in children, particularly when performed for the sole purpose of reversing severe thrombocytopenia resulting from portal hypertension. DSRS was performed in 11 children between the ages of 7 and 15 years: five for severe thrombocytopenia (group 1), four for advanced hypersplenism and congenital hepatic fibrosis prior to renal transplantation (group 2), and two for esophageal bleeding (group 3). One child in group 1 with severe heart disease and Child's class C cirrhosis due to hepatitis C died of progressive cardiac failure and was excluded from further analysis. Of the eight remaining patients in groups 1 and 2, four children had congenital hepatic fibrosis, two had portal vein thrombosis, one had hepatitis B, and one had Wilson's disease. After DSRS, the mean platelet count increased from 37,000 +/- 18,000 to 137,600 +/- 81,000 (P = 0.01). The platelet count improved significantly in all seven children with presinusoidal portal hypertension or stable cirrhosis but did not increase in the child with hepatitis B and Child's class B cirrhosis. The white blood cell count increased from an average of 3.3 +/- 1.1 to 5.4 +/- 2.6 (P= 0.02). There were no postoperative complications in this group. The improved platelet count allowed the four children with congenital hepatic fibrosis and renal failure to undergo renal transplantation with full posttransplant immunosuppression including azathioprine. Postoperative Doppler ultrasound examination demonstrated shunt patency at 6 months in all cases. Spleen size decreased appreciably in all children in groups 1 and 2. All children were able to resume full activity including contact sports. In summary, DSRS effectively controls profound thrombocytopenia resulting from presinusoidal portal hypertension or stable cirrhosis without sacrificing the spleen and should be the treatment of choice for this condition.
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PMID:Distal splenorenal shunts for the treatment of severe thrombocytopenia from portal hypertension in children. 1045 41

Over the last decade the role of diuretics as first-line agents for the treatment of hypertension has diminished substantially. The present review encourages the reader to reconsider the current trend for a decline in the use of these inexpensive antihypertensive drugs whose efficacy is well documented. Diuretics have been used in 16 placebo controlled studies with over 13,000 patients as first-line drugs to lower blood pressure. These drugs were shown to reduce total mortality by 11%, cerebrovascular events by 34% and coronary morbidity by 29%. The magnitude of blood pressure reduction with low-dose thiazide diuretics is comparable to that of a therapy with high-dose thiazides, without the serious metabolic side effects observed with the higher dosage. In combination with other antihypertensive agents, diuretics counteract the compensatory regulatory responses, such as volume expansion and edema formation. Moreover, it has been shown that a combination with low-dose thiazides may not only further decrease blood pressure but also reduce cerebrovascular and coronary mortality. Advantages of diuretics in the treatment of hypertension can be appreciated in special clinical conditions, for instance in patients with edema, heart failure, renal failure, nephrotic syndrome and portal hypertension. Low-dose diuretics still have a place as first-line drugs for the treatment of mild, uncomplicated essential hypertension. Moreover, as opposed to other blood pressure lowering agents, there is sufficient scientific evidence for the primary preventive effect of low-dose thiazide.
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PMID:[Which hypertensive patient requires diuretic therapy?]. 1089 23

Complications of portal hypertension remain perplexing physiologic phenomena in the understanding of shunt hemodynamics with multiple theories. Hyperdynamic circulation was also found in sepsis, chronic anemia and arterio-venous (A-V) fistula which relate to an increase in nitric oxide. We hypothesize that portosystemic collaterals may mimic an A-V fistula in which the high-pressure portal blood connects with the lower pressure systemic venous circulation. Although these collaterals decompress the portal circulation, a number of secondary hemodynamic phenomena occur which increase portal blood flow and tend to counteract the portal hypotensive effect of the portosystemic shunt. The consequent increases in cardiac output and portal blood flow perfuse the compromised liver. As portal blood flow increases, collateral flow increases and is nearly totally shunted in the systemic circulation. This shunt may eventually introduce a vicious cycle of hyperdynamic circulation into a compromised host. Ultimately, high-output cardiac failure occurs, leading to cirrhotic cardiomyopathy.
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PMID:Hyperdynamic circulation in portal hypertension: a comparative model of arterio-venous fistula. 1102 33

Until recently, spironolactone was considered only as an antagonist at the aldosterone receptors of the epithelial cells of the kidney and was used clinically in the treatment of hyperaldosteronism and, occasionally, as a K(+)-sparing diuretic. The spironolactone renaissance started with the experimental finding that spironolactone reversed aldosterone-induced cardiac fibrosis by a cardiac action. Experimentally, spironolactone also has direct effects on blood vessels. Spironolactone reduces vascular fibrosis and injury, inhibits angiogenesis, reduces vascular tone and reduces portal hypertension. The rationale for the Randomized Aldactone Evaluation Study (RALES) of spironolactone in heart failure was that 'aldosterone escape' occurred through non-angiotensin II mechanisms. The RALES clinical trial was stopped early when it was shown that there was a 30% reduction in risk of death among the spironolactone patients. In RALES, spironolactone also reduced hospitalisation for worsening heart failure and improved the symptoms of heart failure. Other recent clinical trials have shown that spironolactone reduces cardiac and vascular collagen turnover, improves heart variability, reduces ventricular arrhythmias, improves endothelial dysfunction and dilates blood vessels in human heart failure and these effects probably all contribute to the increased survival in heart failure. Spironolactone may also be useful in the treatment of left ventricular hypertrophy, portal hypertension and cirrhosis. There have also been some recent small clinical trials of spironolactone as an anti-androgen showing potential in acne, hirsutism and precocious puberty.
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PMID:The spironolactone renaissance. 1132 68

Traumatic hepatic arterioportal fistulae (APF) are described infrequently as sequelae of hepatic trauma. These anomalies are usually associated with blunt hepatic trauma or iatrogenic injury. The majority of APF present within weeks to months of injury with gastrointestinal hemorrhage, hemobilia, abdominal pain, and diarrhea. When presenting remotely APFs are associated with portal hypertension, heart failure, gastrointestinal hemorrhage, ascites, and splenomegaly. We report an unusual case of mesenteric ischemia due to an APF that resulted from a penetrating liver injury 20 years before presentation. Successful treatment of the APF was achieved by intravascular catheter occlusion resulting in resolution of symptoms.
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PMID:Mesenteric ischemia: an unusual presentation of traumatic intrahepatic arterioportal fistula. 1156 65

Most frequent complications in patients with liver cirrhosis are due to portal hypertension. Beside ascites circumvent vessels formate with vasodilatation. Due to counterregulation a secondary hyperaldosteronism develops with release of vasocontrictive agents. If conservative and endoscopic methods fail, indication for building a portosystemic shunt is given. The TIPSS procedure is less invasive than the surgical method of Warren-Shunt, so the radiological intervention has replaced surgery. Reducing the portal pressure by the shunt, the clinical complications change for the better. Still problems are defined as hepatic encephalopathy and right ventricular heart failure. Regular follow up investigations have to be performed to detect complications in the shunt. Using regular clinical and radiological check up TIPSS is of clinical benefit with good long term results.
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PMID:[Transjugular portosystemic stent shunt (TIPSS) as intervention in clinical complications of portal hypertension]. 1171 78

Overactivity of the sympathetic nervous system and portal hypertension are key factors in the development of ascites in cirrhosis. The sympathoexcitation that characterizes the more advanced stages of liver diseases is less clearly defined in preascitic cirrhosis. We measured sympathetic nerve traffic to skeletal muscle (peroneal nerve) and to skin districts by microneurography in (1) 12 Child class A cirrhotic patients with clinically significant portal hypertension (portal pressure gradient > 10 mm Hg, 14.8 +/- 1.2 mm Hg, mean +/- SEM) but without actual or previous ascites, (2) 16 Child class C cirrhotic patients with tense ascites, and (3) 10 patients with mild congestive heart failure, a condition paradigmatic of a marked sympathetic activation. Muscle sympathetic nerve traffic was markedly increased in Child class C subjects as compared with controls (23.9 +/- 1.6 bursts/min, P <.01) and superimposable to that recorded in heart failure patients (52.9 +/- 4.7 vs. 60.3 +/- 2 bursts/min, P = not significant). Muscle sympathetic nerve traffic was also increased in Child class A subjects (41.6 +/- 2 bursts/min, P <.01 vs. controls) although to a lesser extent (P <.05 vs. Child class C patients). Skin sympathetic nerve traffic was within the normal range in all patients. Neurohormones were all markedly increased in Child class C subjects. Only norepinephrine was increased in Child class A patients. Our data show that sympathetic nerve traffic activation (1) is already detectable in Child class A cirrhosis when clinically significant portal hypertension is present but ascites never developed and (2) is not generalized because although muscle traffic is increased, skin traffic is within normal range. The role of drugs modulating sympathoactivation should be investigated in preascitic cirrhosis.
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PMID:Patterns of regional sympathetic nerve traffic in preascitic and ascitic cirrhosis. 1173

Clinical trials have established bosentan, an orally active non-selective endothelin (ET) receptor antagonist, as a beneficial treatment in pulmonary hypertension. Trials have also shown short-term benefits of bosentan in systemic hypertension and congestive heart failure. However, bosentan also increased plasma levels of ET-1, probably by inhibiting the clearance of ET-1 by endothelin type B (ET(B)) receptors, and this may mean its effectiveness is reduced with long-term clinical use. Preliminary data suggests that selective endothelin type A (ET(A)) receptor antagonists (BQ-123, sitaxsentan) may be more beneficial than the non-selective ET receptor antagonists in heart failure, especially when the failure is associated with pulmonary hypertension. Experimental evidence in animal disease models suggests that non-selective ET or selective ET(A) receptor antagonism may have a role in the treatment of atherosclerosis, restenosis, myocarditis, shock and portal hypertension. In animal models of myocardial infarction and/or reperfusion injury, non-selective ET or selective ET(A) receptor antagonists have beneficial or detrimental effects depending on the conditions and agents used. Thus clinical trials of the non-selective ET or selective ET(A) receptor antagonists in these conditions are not presently warranted. Several selective endothelin-converting enzyme inhibitors have been synthesised recently, and these are only beginning to be tested in animal models of cardiovascular disease, and thus the clinical potential of these inhibitors is still to be defined.
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PMID:The therapeutic potential of endothelin-1 receptor antagonists and endothelin-converting enzyme inhibitors on the cardiovascular system. 1243 1

Portopulmonary hypertension is a rare complication of portal hypertension. Although epoprostenol infusion, nitric oxide inhalation, isosorbide-5-mononitrate, nitroglycerin, and calcium channel blockers may reduce pulmonary artery pressure in patients with portopulmonary hypertension, the prognosis remains poor. We present a case of congenital hepatic fibrosis associated with pulmonary hypertension. A 42-year-old man with congenital hepatic fibrosis visited our hospital with syncope. The man had suffered from breathlessness on exertion for 2 weeks before the episode of syncope. He also had a history of portal hypertension with documented gastric cardiac varices at the age of 28 years. Despite undergoing intensive care, the patient died 1 week after admission owing to severe right-sided heart failure. Autopsy revealed dilatation of the right atrium and right ventricle grossly and plexogenic pulmonary arteriopathy microscopically. Accurate diagnosis of portopulmonary hypertension requires awareness of the disease and a high index of suspicion when examining patients with portal hypertension and dyspnea.
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PMID:Severe portopulmonary hypertension in congenital hepatic fibrosis. 1279 Feb 24


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