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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Liver disease affects the lungs. The majority of patients exhibit mild to moderate arterial hypoxaemia essentially attributable to an alteration in ventilation/perfusion matching and limited by an increase in ventilation. A minority (some 10%) of patients exhibit a "hepatopulmonary syndrome" defined by severe hypoxaemia with arterial PO2 below 60 mm Hg, dyspnoea, cyanosis, digital clubbing, orthodeoxia, platypnoea and demonstrable pulmonary vascular dilatations causing a true pulmonary shunt and a diffusion/perfusion imbalance. The hepatopulmonary syndrome is incurable but resolves over time after liver transplantation. An even lower proportion of patients, approximately 1%, develop pulmonary hypertension. Clinically this "portopulmonary hypertension" resembles primary pulmonary hypertension, with dyspnoea and fatigue as the main symptoms, histopathology and response to prostacyclin therapy. Portopulmonary hypertension is irreversible. Liver transplantation mortality in patients with portopulmonary hypertension ranges from 50 to 100%. The common cause of the hepatopulmonary syndrome and portopulmonary hypertension is portal hypertension and portosystemic shunting, indicating that vasoactive and angiogenetic factors originating from the liver normally control the pulmonary circulation.
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PMID:Hepatopulmonary syndrome and portopulmonary hypertension. 1271 85

Portopulmonary hypertension is an uncommon but treatable pulmonary vascular consequence of portal hypertension, which can lead to significant morbidity and mortality. Portopulmonary hypertension results from excessive pulmonary vasoconstriction and vascular remodeling that eventually leads to right-heart failure and death if left untreated. Although pulmonary vascular disease in these patients may be asymptomatic or associated with subtle and nonspecific symptoms (dyspnea, fatigue and lower extremity swelling), it should be looked for especially if patients are potential candidates for liver transplantation. Patients with clinical suspicion of portopulmonary hypertension should undergo screening testing, specifically echocardiography. Right heart catheterization remains the gold standard for the diagnosis. The existence of moderate to severe disease poses higher risks and challenges for liver transplantation. The disease has a substantial impact on survival and requires focused pharmacological therapy. New and evolving medical therapies, such as prostanoids (intravenous, inhaled or oral), endothelin receptors antagonists, phosphodiesterases inhibitors, combination therapy and other experimental drugs might change the natural course of the disease. Case reports and cases series have been published regarding the efficacy and safety of pharmacological therapy, but randomized, controlled multicenter trials are urgently needed. Liver transplantation is not the treatment of choice for portopulmonary hypertension, but after optimal hemodynamic and clinical improvement with medical therapy as a bridge, liver transplant can be considered an option in selected patients.
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PMID:Portopulmonary hypertension: state of the art. 1903 31

The pulmonary complications of end-stage liver disease include hepatopulmonary syndrome and portopulmonary hypertension. The etio-pathogenesis of these conditions is as yet unclear. Hepatopulmonary syndrome is a gas exchange abnormality and usually manifests as hypoxemia secondary to intra-pulmonary vascular shunts. These shunts can be demonstrated by echocardiography using agitated saline injections, and quantitated by lung perfusion scans. Liver transplantation is the treatment of choice for hepatopulmonary syndrome, and there are no effective pharmacological therapies. Portopulmonary hypertension is a hemodynamic problem which manifests as fatigue and right sided cardiac failure. Several vasoactive agents have been used to lower mean pulmonary arterial pressures. Portopulmonary hypertension is a relative contraindication to liver transplantation.
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PMID:Hepatopulmonary syndrome and portopulmonary hypertension. 1979 40

Portopulmonary hypertension (PPHT) is a respiratory complication of portal hypertension, defined as an increase in mean pulmonary artery pressure (PAP) of > 25 mmHg with an increase in pulmonary vascular resistance of > 240 dyn.s/cm(-5) and a normal pulmonary capillary wedge pressure ( < 15 mmHg), which often occurs in subjects with liver cirrhosis. Histopathological features of PPHT are endothelial and smooth-muscle cell proliferation and fibrosis leading to luminal obstruction in the resistance arteries. The pathogenesis of PPHT may result from an imbalance between vasoconstrictor and vasodilating factors. The most common pulmonary symptom is exertional dyspnea; fatigue, chest pain and syncope occur more often at an advanced stage. Edema, ascites and prominent jugular veins are signs of both decompensated hepatic cirrhosis and right ventricular failure. Right heart catheterisation is the gold standard for the diagnosis and defines PPHT in mild disease with PAP less than 35 mmHg, moderate disease with PAP between 35 and 45 mmHg, and severe disease with PAP of 45 mmHg or higher. The medical treatment of portopulmonary hypertension is based on the treatment of other forms of pulmonary arterial hypertension, including vasomodulating pharmacologic agents. Liver transplantation is accompanied by high risk of mortality, generally due to acute right ventricular failure and cardiovascular collapse. The prognosis of PPHT is poor with mean survival of 15 months.
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PMID:Portopulmonary hypertension. 2163 86

Portopulmonary hypertension is one of the main pulmonary conditions affecting patients with liver disease and/or portal hypertension. Other conditions include hepatopulmonary syndrome and hepatic hydrothorax. Portopulmonary hypertension is caused by pulmonary vasoconstriction and increased pulmonary vascular resistance. It develops as a result of portal hypertension with or without liver disease and is associated with a higher morbidity and mortality. However, portopulmonary hypertension is usually asymptomatic; the most common symptoms are dyspnea, fatigue, and peripheral edema. All liver transplant candidates should be screened for potential portopulmonary hypertension because its coexistence can affect survival rates after transplant. All patients with cirrhosis who present with dyspnea should also be screened. Transthoracic echocardiography is a noninvasive, useful method for screening, but right heart-sided catheterization remains the criterion standard for diagnosis. Portopulmonary hypertension carries a poor prognosis without liver transplant, and its severe form is considered to be a contraindication for liver transplant. Treating patients with pulmonary arterial hypertension-specific therapies before liver transplant for moderate and severe portopulmonary hypertension appears to be beneficial.
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PMID:Portopulmonary Hypertension and Liver Transplant: Recent Review of the Literature. 2701 28