Recenti progressi in medicina
-
The liver controls pulmonary vascular tone by releasing vasoactive substances. In severe liver failure, the imbalance between vasodilator and vasoconstrictive mediators may lead to alteration of the respiratory function, called as hepatopulmonary syndrome (HPS, when a significant decrease of the vascular pulmonary resistance occurs, with development of intrapulmonary vascular dilatations) and portopulmonarv hypertension (PPH, when the vasoconstrictive prevalence, with an increase of the pulmonary vascular resistances). ⋯ The alteration of pulmonary vascularization may be diagnosed by means of pulmonary angiography, contrast-enhanced echocardiography and perfusion lung nuclear scanning of the lungs. Both clinical syndromes respond poorly to medical treatment, the unique therapeutical possibilities being represented by orthotopic liver transplantation (or combined heart-lung-liver or lung-liver transplantation in patients with severe PPH).