Síndrome hepatopulmonar: revisión narrativa / Hepatopulmonary syndrome: a narrative revision

Resumen: el síndrome hepatopulmonar es una de las tres principales condiciones pulmonares en pacientes con enfermedad hepática o hipertensión portal. Esta alteración es causada por la circulación hiperdinámica, los cortocircuitos intrapulmonares y la vasodilatación pulmonar, lo que lleva a alteraciones que generan un compromiso en el intercambio gaseoso, el cual se manifiesta como hipoxemia y aumento del gradiente alveolo arterial. El diagnóstico del síndrome hepatopulmonar consiste en demostrar las alteraciones del intercambio gaseoso, por medio del análisis de los gases arteriales, y las dilataciones vasculares intrapulmonares, documentadas por ecocardiografía transtorácica contrastada con solución salina agitada, la cual es considerada el estándar de referencia. Por el impacto pronóstico del síndrome hepatopulmonar, se recomienda una tamización activa que permita un diagnóstico temprano, y referir a tiempo al paciente a un centro especializado para la valoración de trasplante hepático como único tratamiento disponible curativo. El objetivo de este artículo es proporcionar una revisión narrativa sobre el síndrome hepatopulmonar, con énfasis en la definición, diagnóstico, fisiopatogénesis y medidas terapéuticas disponibles. (AU)

Abstract: Hepatopulmonary syndrome is one of the three main pulmonary disorders affecting patients with liver disease or portal hypertension. This disease is caused by hyperdynamic circulation, intrapulmonary shunts, and pulmonary vasodilation, which leads to disturbances in gas exchange, evidenced by hypoxemia and increased alveolar-arterial gradient. Diagnosis of hepatopulmonary syndrome requires arterial blood gas analysis and documentation of intrapulmonary vascular dilation by transthoracic echocardiogram with agitated saline contrast; the gold standard for hepatopulmonary syndrome diagnosis. Due to the prognostic value of hepatopulmonary syndrome, active screening is recommended in order to achieve early diagnosis and timely patient referral to a specialized center to be evaluated as a candidate for liver transplant, as it currently is the only available curative treatment. The aim of this article is to provide a narrative review of current literature on hepatopulmonary syndrome, focusing on its definition, diagnosis, physiopathogenesis, and available therapeutic approaches. (AU)

A Case of Hepatopulmonary Syndrome / 대한내과학회지

Hepatopulmonary syndrome consists of a triad of liver dysfunction, intrapulmonary vascular dilatation, and hypoxemia. This is one of the main causes of arterial hypoxemia in patients with chronic liver disease. The vascular abnormalities are precapillary dilatation, direct arterial-venous communication, and dilated pleural vessels. In this article, we report a case of hepatopulmonary syndrome in a 62-year-old woman who had complained progressively worsening dyspnea, platypnea, and orthodeoxia. She had huge splenomegaly, clubbing fingers and cyanosis of lip and fingers. Arterial blood gas analysis showed refractory arterial hypoxemia and orthodeoxia suggesting right-to-left "shunting". Chest X-ray showed increased interstitial markings on the lower part of right lung, In 99mTc-labeled macroaggregated albumin (MAA) lung perfusion scan, there was no perfusion defect in the lung, but labeled radionuclide were taken up in the intraabdominal organs, kidney, liver and spleen. The amount of shunted radionuclide were about 58 percent. In contrast echocardiography, microbubbles which were injected via cephalic vein were visualized in the left atrium at 4 cardiac cycles after leaving the right ventricle indicating intrapulmonary right-to-left "shunting" rather than intracardiac shunt. Pulmonary angiographic finding revealed diffuse blotchy arterial dilatation on both lung fields, especially lower lobes of both lungs. Current modalities of treatment of hepatopulmonary syndrome are the therapeutic embolization of direct arterial-venous communication for focal vascular dilatations, and TIPSS (Transjugular intrahepatic porto-systemic shunt) or liver transplantation for diffuse intrapulmonary vascular dilatations. Despite our recommendation of TIPSS, she refused the procedure and is under home oxygen therapy.