Findings of hepatopulmonary syndrome on breath-hold perfusion SPECT-CT fusion images

Hepatopulmonary syndrome: diagnosis and treatment

Hepatopulmonary syndrome (HPS) is one of the lung diseases associated with liver cirrhosis and portal hypertension. The diagnosis is based on the triad: liver disease and portal hypertension, evidence of intrapulmonary vascular dilatation and impaired gas exchange. HPS impairs prognosis (23 % survival after 5 years) and patients’ quality of life, so early diagnosis and timely treatment are of great importance. Liver transplantation allows for regression of intrapulmonary vascular dilatation in almost 100 % of cases, normalization of gas exchange and improves a 5-year survival after transplantation from 76 to 87 %. This is the only treatment method indicated for patients with severe HPS, defined by an arterial partial pressure of oxygen (PaO2) below 60 mm Hg. However, in the face of a global shortage of transplants, it is necessary to develop medical therapies to delay or even defer liver transplantation. This goal seems possible due to the growing understanding of the HPS pathophysiology and the development of therapies targeting key mechanisms, mainly inflammatory and angiogenic. This article provides an overview of the clinical manifestations, diagnosis and treatment of HPS based on literature sources from the MEDLINE database on the PubMed platform.

Chest ultrasound findings in hepatopulmonary fusion (HPF)

Hepatopulmonary fusion (HPF) is an extremely rare condition characterized by a fusion between the herniated liver and lung right parenchyma. Knowledge about this condition comes from the few cases reported in the literature (less than 40 cases). While diagnostic evaluation as X-Ray, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and Single Photon Emission Computed Tomography (SPECT) were described, poor ultrasound findings are available. In this paper, the authors provide the detailed chest ultrasound findings of this rare condition.

Shortness of breath due to portopulmonary hypertension and hepatopulmonary syndrome: diagnostic challenges and complex management approach in frail patients

A 60-year-old woman with a background of frailty, non-alcoholic fatty liver disease (NAFLD), cirrhosis and type 2 diabetes mellitus (T2DM), presented with worsening shortness of breath and a drop in oxygen saturation on sitting and standing up. Her chest X-ray demonstrated evidence of upper lobe venous diversion. Given the hypoxia, she had a computed tomography pulmonary angiography (CTPA) to rule out a pulmonary embolism. The only finding from the CTPA was pulmonary hypertension in the absence of any clots in the lungs. An ultrasound of the abdomen confirmed portal hypertension with splenomegaly and a cirrhotic liver, therefore, an initial diagnosis of portopulmonary hypertension and hepatopulmonary syndrome was made. The patient declined an agitated saline contrast echocardiography. Based on frailty she was not deemed to be a suitable candidate for a liver transplant and was discharged with a package of care alongside home oxygen therapy with periodic review in the gastroenterology clinic. She was assessed as stable with no new concerns while on home oxygen and diuretics. This case highlights challenges in diagnosing and managing patients with cirrhosis, portopulmonary hypertension and hepatopulmonary syndrome with a background of complex comorbidities and frailty.

Advances in Diagnostic Imaging of Hepatopulmonary Syndrome

Hepatopulmonary syndrome (HPS) is a serious pulmonary complication of progressive liver disease that leads to a poor clinical prognosis. Patients with HPS may develop acute respiratory failure, which requires intensive care and therapy. At present, the only effective treatment is liver transplantation; therefore, early diagnosis and timely treatment are of considerable significance. The three main features of HPS are liver disease, oxygenation disorder, and intrapulmonary vascular dilatation (IPVD). Diagnosing HPS is challenging due to the difficulty in detecting the presence or absence of IPVD. As such, imaging examination is very important for detecting IPVD. This paper reviews the imaging methods for diagnosing HPS such as ultrasound, dynamic pulmonary perfusion imaging, pulmonary angiography, and computed tomography.

Hepatopulmonary syndrome: What we know and what we would like to know

Hepatopulmonary syndrome (HPS) is characterized by abnormalities in blood oxygenation caused by the presence of intrapulmonary vascular dilations (IPVD) in the context of liver disease, generally at a cirrhotic stage. Knowledge about the subject is still only partial. The majority of the information about the etiopathogenesis of HPS has been obtained through experiments on animals. Reported prevalence in patients who are candidates for a liver transplantation (LT) varies between 4% and 32%, with a predominance of mild or moderate cases. Although it is generally asymptomatic it does have an impact on their quality of life and survival. The diagnosis requires taking an arterial blood gas sample of a seated patient with alveolar-arterial oxygen gradient (AaO₂) ≥ 15 mm Hg, or ≥ 20 mm Hg in those over 64 years of age. The IPVD are identified through a transthoracic contrast echocardiography or a macroaggregated albumin lung perfusion scan (^99mTc-MAA). There is currently no effective medical treatment. LT has been shown to reverse the syndrome and improve survival rates, even in severe cases. Therefore the policy of prioritizing LT would appear to increase survival rates. This paper takes a critical and clinical look at the current understanding of HPS, as well as the controversies surrounding it and possible future research.

Hepatopulmonary syndrome: update on pathogenesis and clinical features

Hepatopulmonary syndrome (HPS) is a serious vascular complication of liver disease that occurs in 5-32% of patients with cirrhosis. The presence of HPS markedly increases mortality. No effective medical therapies are currently available and liver transplantation is the only established treatment option for HPS. The definition and diagnosis of HPS are established by the presence of a triad of liver disease with intrapulmonary vascular dilation that causes abnormal arterial gas exchange. Experimental biliary cirrhosis induced by common bile duct ligation in the rat reproduces the pulmonary vascular and gas exchange abnormalities of human HPS and serves as a pertinent animal model. Pulmonary microvascular dilation and angiogenesis are two central pathogenic features that drive abnormal pulmonary gas exchange in experimental HPS, and thus might underlie HPS in humans. Defining the mechanisms involved in the microvascular alterations of HPS has the potential to lead to effective medical therapies. This Review focuses on the current understanding of the pathogenesis, clinical features and management of HPS.

Pulmonary vascular complications of chronic liver disease: Pathophysiology, imaging, and treatment

To review the pathogenesis of pulmonary vascular complications of liver disease, we discuss their clinical implications, and therapeutic considerations, with emphasis on potential reversibility of the hepatopulmonary syndrome after liver transplantation. In this review, we also discuss the role of imaging in pulmonary vascular complications associated with liver disease.