Association between primary pulmonary hypertension and portal hypertension: analysis of its pathophysiology and clinical, laboratory and hemodynamic manifestations

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Respiratory problems associated with liver disease in children

Respiratory manifestations of chronic liver disease have a profound impact on patient clinical outcomes. Certain conditions within paediatric liver disease have an associated respiratory pathology. This overlap between liver and respiratory manifestations can result in complex challenges when managing patients and requires clinicians to be able to recognise when referral to specialists is required. While liver transplantation is at the centre of treatment, it opens up further potential for respiratory complications. It is established that these complications place patients at risk of longer stays in hospital and reduced survival. Additionally, late post-transplant complications can occur, including post-transplant lymphoproliferative disease and immunosuppression-induced interstitial lung disease. Although rare, it is important for clinicians to recognise these conditions to allow for prompt management. Finally, as liver disease progresses in children, respiratory complications can occur. Hepatopulmonary syndrome can occur in the context of portal hypertension, resulting in increased mortality and poorer quality of life for patients. Another consequence is portopulmonary hypertension, which can be associated with poor survival. Failure to recognise these complications in children may result in poorer outcomes and therefore it is vital that clinicians can establish when referral to a paediatric respiratory medicine specialist is required.

Symptom-based portopulmonary hypertension screening questionnaire in Japanese patients with chronic liver disease

Background and Aim

As the exact prevalence of portopulmonary hypertension (PoPH) and the etiology of chronic liver disease (CLD) remain unknown, the present study aimed to clarify these points in Japanese patients with CLD using symptom-based questionnaire screening.

Methods

Patients with CLD were asked to complete an eight-item written questionnaire on pulmonary hypertension (PH) symptoms. If at least one item response was "yes," the patient was offered ultrasonic echocardiography (UCG). Patients identified as having an intermediate or high risk of PH by UCG were referred to a cardiologist for further evaluation, whereby a definitive diagnosis of PoPH was made using right heart catheterization (RHC) findings.

Results

A total of 1111 patients with CLD completed the survey. Of the 566 symptomatic patients with at least one question answered as "yes," approximately half agreed to undergo UCG (n = 267). Compared with asymptomatic patients, symptomatic patients were significantly older, predominantly female, and more frequently exhibited cirrhosis. Based on UCG findings, 228, 12, and 8 patients had a low, intermediate, or high risk for PH, respectively. Intermediate-/high-risk patients showed significantly more advanced disease progression status than low-risk patients. The frequencies of answer to the eight questions were comparable. Ultimately, three patients were diagnosed as having PoPH (1.1% of UCG cases), one with underlying hepatitis C virus (HCV) infection and two with primary biliary cholangitis (PBC).

Conclusion

This symptom-based PoPH screening study clarified the prevalence of PoPH in CLD patients according to a PH symptom questionnaire, UCG, and RHC. Patients with HCV and PBC may have a higher risk of PoPH.

Shiny transcriptional junk: lncRNA-derived peptides in cancers and immune responses

By interacting with DNA, RNA, and proteins, long noncoding RNAs (lncRNAs) have been linked to several pathological states. LncRNA-derived peptides, as a novel modality of action of lncRNAs, have recently become a research hotspot. An increasing body of evidence has demonstrated the important role of these peptides in carcinogenesis and cancer progression and immune response. This review first describes lncRNA-derived peptides, the regulators that control their translation, and the roles of these peptides in multiple biological processes and disease states including cancers. In the following section, we comprehensively analyzed the significant role lncRNA-derived peptide played in the immune response. This review provides fresh perspectives on the biological role of lncRNAs and their relationship with diseases, particularly with cancers and the immune response, providing a theoretical basis for these lncRNA-derived peptides as therapeutic and diagnostic targets in cancers and inflammatory diseases.

Risk factors for portopulmonary hypertension in patients with cirrhosis: a prospective, multicenter study

BACKGROUND

Tricuspid regurgitation pressure gradient (TRPG) measurement by echocardiography is recommended as the most objective examination to detect portopulmonary hypertension (PoPH). This study aimed to identify factors associated with a high TRPG in patients with cirrhosis and develop a scoring model for identifying patients who are most likely to benefit from echocardiography investigations.

RESULTS

A total of 486 patients who underwent echocardiography were randomly allocated to the derivation and validation sets at a ratio of 2:1. Of the patients, 51 (10.5%) had TRPG ≥ 35 mmHg. The median brain natriuretic peptide (BNP) was 39.5 pg/mL. Shortness of breath (SOB) was reported by 91 (18.7%) patients. In the derivation set, multivariate analysis identified female gender, shortness of breath, and BNP ≥ 48.9 pg/mL as independent factors for TRPG ≥ 35 mmHg. The risk score for predicting TRPG ≥ 35 mmHg was calculated as follows: - 3.596 + 1.250 × gender (female: 1, male: 0) + 1.093 × SOB (presence: 1, absence: 0) + 0.953 × BNP (≥ 48.9 pg/mL: 1, < 48.9 pg/mL: 0). The risk score yielded sensitivity of 66.7%, specificity of 75.3%, positive predictive value of 25.5%, negative predict value of 94.3%, and predictive accuracy of 74.4% for predicting TRPG ≥ 35 mmHg. These results were almost similar in the validation set, indicating the reproducibility and validity of the risk score.

CONCLUSIONS

This study clarified the characteristics of patients with suspected PoPH and developed a scoring model for identifying patients at high risk of PoPH, which may be used in selecting patients that may benefit from echocardiography.

Portopulmonary Hypertension

PoPH is a well-recognized complication of portal hypertension with or without cirrhosis and is classified as a subset of PAH. Identification of PoPH is crucial as it has a major impact on prognosis and liver transplant candidacy. Echocardiogram is the initial screening tool of choice and the patient should proceed to RHC for confirmation. PAH-directed therapy is the treatment of choice, allowing the patient to achieve a hemodynamic threshold to undergo a liver transplant safely.

Efficacy evaluation of pulmonary hypertension therapy in patients with portal pulmonary hypertension: A systematic review and meta-analysis

Objective: To determine the therapeutic effect of pulmonary arterial hypertension (PAH) agents for portal pulmonary hypertension (POPH).

Design: Systematic review and meta-analysis.

Background: POPH is a serious complication of end-stage liver disease with a low survival rate. Liver transplantation (LT) is an effective treatment. Due to the presence of POPH, some patients cannot undergo LT. After PAH treatment, patients with POPH can obtain good hemodynamics and cardiac function for LT, but there are no standard guidelines.

Methods: Two independent researchers searched PubMed, EMBASE, Cochrane Library, and Web of Science for studies published from inception to 27 September 2022, focusing on the changes in hemodynamics and cardiac function in all patients with POPH to understand the effect of PAH treatment on the entire population of POPH patients. Among these, we specifically analyzed the changes in hemodynamics and cardiac function in moderate and severe POPH patients. After collecting the relevant data, a meta-analysis was carried out using the R program meta-package.

Results: A total of 2,775 literatures were retrieved, and 24 literatures were included. The results showed that in all POPH patients (n = 1,046), the following indicators were significantly improved with PAH agents: mPAP: (MD = −9.11 mmHg, p &lt; 0.0001); PVR: (MD = −239.33 dyn·s·cm−5, p &lt; 0.0001); CO: (MD = 1.71 L/min, p &lt; 0.0001); cardiac index: (MD = 0.87 L/(min·m2), p &lt; 0.0001); 6MWD: (MD = 43.41 m, p &lt; 0.0001). In patients with moderate to severe POPH (n = 235), the following indicators improved significantly with PAH agents: mPAP (MD = −9.63 mmHg, p &lt; 0.0001); PVR (MD = −259.78 dyn·s·cm−5, p &lt; 0.0001); CO (MD = 1.76 L/min, p &lt; 0.0001); Cardiac index: (MD = 1.01 L/(min·m2), p = 0.0027); 6MWD: (MD = 61.30 m, p &lt; 0.0001).

Conclusion: The application of PAH agents can improve cardiopulmonary hemodynamics and cardiac function in patients with POPH, especially in patients with moderate to severe POPH, and the above changes are more positive.

Systematic Review Registration:https://inplasy.com, identifier INPLASY202250034.

Simple algorithm to narrow down the candidates to receive echocardiography in patients with chronic liver disease for suspected pulmonary hypertension

Aims

Portopulmonary hypertension (PoPH) is a subtype of pulmonary arterial hypertension related to portal hypertension. The definitive diagnosis of PoPH is made by invasive right heart catheterization. Alternatively, pulmonary arterial hypertension may be recognized noninvasively from the tricuspid regurgitant pressure gradient (TRPG), measured by echocardiography. In this study, we aimed to establish a simple algorithm to identify chronic liver disease patients with a high TRPG value in order to narrow down the candidates to receive echocardiography.

Methods and Results

TRPG was measured by echocardiography in 152 patients with chronic liver disease. Factors predictive of TRPG >30 mmHg were investigated. There were 28 (18%) cases with TRPG >30 mmHg. Independent factors associated with a high TRPG were the presence of shortness of breath, high serum brain natriuretic peptide (BNP), and low serum albumin. Child–Pugh class or the presence of ascites, varices, or encephalopathy was not associated with TRPG. There was a correlation between the serum BNP and TRPG, and the optimal cutoff value of BNP by the Youden index was 122 pg/mL, and by 100% sensitivity was 50 pg/mL. A combination of these factors identified patients with a high probability of TRPG >30 mmHg (n = 12, positive predictive value [PPV] of 83%), no probability (n = 80, PPV 0%), and intermediate probability (n = 60, PPV 25–34%). This algorithm has reduced the number of patients needing echocardiography by 53%.

Conclusions

A simple algorithm using the presence of shortness of breath, serum BNP, and albumin levels can narrow down the candidates to receive echocardiography.

Cardiac risk stratification of the liver transplant candidate: A comprehensive review

Cardiovascular diseases (CVD) form a principal consideration in patients with end-stage liver disease (ESLD) undergoing evaluation for liver transplant (LT) with prognostic implications in the peri- and post-transplant periods. As the predominant etiology of ESLD continues to evolve, addressing CVD in these patients has become increasingly relevant. Likewise, as the number of LTs increase by the year, the proportion of older adults on the waiting list with competing comorbidities increase, and the demographics of LT candidates evolve with parallel increases in their CVD risk profiles. The primary goal of cardiac risk assessment is to preemptively reduce the risk of cardiovascular morbidity and mortality that may arise from hemodynamic stress in the peri- and post-transplant periods. The complex hemodynamics shared by ESLD patients in the pre-transplant period with adverse cardiovascular events occurring in only some of these recipients continue to challenge currently available guidelines and their uniform applicability. This review focusses on cardiac assessment of LT candidates in a stepwise manner with special emphasis on preoperative patient optimization. We hope that this will reinforce the importance of cardiovascular optimization prior to LT, prevent futile LT in those with advanced CVD beyond the stage of optimization, and thereby use the finite resources prudently.

Porto-pulmonary arterial hypertension: Translation of pathophysiological concepts to the bedside

Porto-pulmonary arterial hypertension (PoPAH) is a form of pulmonary arterial hypertension (PAH) that affects patients with cirrhosis, and - to a lesser extent - patients with non-cirrhotic liver diseases. Compared with other forms of PAH, PoPAH is more prevalent in male, in older subjects, and is characterized by lower mean pulmonary arterial pressure (mPAP) and lower pulmonary vascular resistance (PVR) with higher cardiac output. Despite more favorable hemodynamics and functional class, patients with PoPAH have a significantly worse survival than patients with other forms of PAH, likely because of liver-related events and therapeutic barriers to PAH-specific therapy. Furthermore, here cardiopulmonary and hepatic complications may affect treatment efficacy. These patients have been excluded from most randomized clinical trials testing PAH-specific treatments. To date, there is only one study investigating efficacy, safety, tolerability and pharmacokinetics of PAH-specific therapy in patients with PoPAH in a randomized placebo-controlled setting. In this trial the use of the endothelin-1 receptor antagonist macitentan showed clear hemodynamic benefit without safety concerns. However, the drug effects on functional capacity and mortality remain unclear. Here we review the current knowledge on the pathophysiology and management of PoPAH and report a case vignette of a patient with PoPAH due to hepatorenal polycystic disease.

Portopulmonary Hypertension: A Review of the Current Literature

Portopulmonary hypertension is defined as the development of pulmonary arterial hypertension in the setting of portal hypertension with or without liver cirrhosis. Portal hypertension-associated haemodynamic changes, including hyperdynamic state, portosystemic shunts and splanchnic vasodilation, induce significant alterations in pulmonary vascular bed and play a pivotal role in the pathogenesis of the disease. If left untreated, portopulmonary hypertension results in progressive right heart failure, with a poor prognosis. Although Doppler echocardiography is the best initial screening tool for symptomatic patients and liver transplantation candidates, right heart catheterisation remains the gold standard for the diagnosis of the disease. Severe portopulmonary hypertension exerts a prohibitive risk to liver transplantation by conferring an elevated perioperative mortality risk. It is important for haemodynamic parameters to correspond with non-severe portopulmonary hypertension before patients can proceed with the liver transplantation. Small uncontrolled studies and a recent randomised controlled trial have reported promising results with vasodilatory therapies in clinical and haemodynamic improvement of patients, allowing a proportion of patients to undergo liver transplantation. In this review, the epidemiology, pathogenesis, diagnostic approach and management of portopulmonary hypertension are discussed. We also highlight fields of ongoing investigation pertinent to risk stratification and optimal patient selection to maximise long-term benefit from currently available treatments.

Screening for portopulmonary hypertension using computed tomography-based measurements of the main pulmonary artery and ascending aorta diameters in patients with portal hypertension

AIM

This study aimed to demonstrate the feasibility of identifying candidates of portopulmonary hypertension (PoPH) from general portal hypertension patients based on chest computed tomography (CT) results.

METHODS

One hundred and thirty patients with portal hypertension who had undergone interventional radiology therapies at our hospital between August 2011 and July 2021 were included, and preoperative clinical data were collected. Suspicious PoPH was defined as main pulmonary artery diameter (mPA-D) ≥ 29 mm or the ratio of mPA-D to ascending aorta diameter (mPA-D/aAo-D) ≥ 1.0, and probable PoPH as mPA-D ≥ 33 mm based on the chest CT. Prevalence of suspicious and probable PoPH was evaluated, and the differences in clinical characteristics of each population were compared.

RESULTS

Overall, 29 (22.3%) and 5 (3.8%) patients were categorized as suspicious and probable PoPH, respectively. Univariate analyses revealed that female sex, higher shortest diameter of inferior vena cava, presence of portosystemic shunts ≥ 5 mm, and lower blood urea nitrogen levels were significantly associated with suspicious PoPH (p < 0.05). Multivariate analyses identified all four factors as significantly independent determinants of suspicious PoPH (p < 0.05). In addition, among the population of suspicious PoPH, there were significant differences in seven parameters, including total bilirubin levels and spleen volume between patients with and without probable PoPH (p < 0.05). However, no significant independent indicators of probable PoPH were found.

CONCLUSIONS

CT-based measurements of mPA-D and mPA-D/aAo-D have the potential to screen patients with suspicious PoPH in clinical practice focused on portal hypertension.

lnc-Rps4l-encoded peptide RPS4XL regulates RPS6 phosphorylation and inhibits the proliferation of PASMCs caused by hypoxia

Pulmonary artery smooth muscle cells (PASMCs) proliferation caused by hypoxia is an important pathological process of pulmonary hypertension (PH). Prevention of PASMCs proliferation can effectively reduce PH mortality. Long non-coding RNAs (lncRNAs) are involved in the proliferation process. Recent evidence has demonstrated that functional peptides encoded by lncRNAs play important roles in cell pathophysiological process. Our previous study has demonstrated that lnc-Rps4l with high coding ability mediates the PASMCs proliferation under hypoxic conditions. We hypothesize in this study that a lnc-Rps4l-encoded peptide is involved in hypoxic-induced PASMCs proliferation. The presence of peptide 40S ribosomal protein S4 X isoform-like (RPS4XL) encoded by lnc-Rps4l in PASMCs under hypoxic conditions was confirmed by bioinformatics, immunofluorescence, and immunohistochemistry. Inhibition of proliferation by the peptide RPS4XL was demonstrated in hypoxic PASMCs by MTT, bromodeoxyuridine (BrdU) incorporation, and immunofluorescence assays. By using the bioinformatics, coimmunoprecipitation (coIP), and mass spectrometry, RPS6 was identified to interact with RPS4XL. Furthermore, lnc-Rps4l-encoded peptide RPS4XL inhibited the RPS6 process via binding to RPS6 and inhibiting RPS6 phosphorylation at p-RPS6 (Ser240+Ser244) phosphorylation site. These results systematically elucidate the role and regulatory network of Rps4l-encoded peptide RPS4XL in PASMCs proliferation. These discoveries provide potential targets for early diagnosis and a leading compound for treatment of hypoxic PH.

Protocol: Prospective observational study investigating the prevalence and clinical outcome of portopulmonary hypertension in Japanese patients with chronic liver disease

BACKGROUND

Portopulmonary hypertension (PoPH) is a subtype of the pulmonary arterial hypertension (PAH) associated with portal hypertension. There is a dissociation between the proportion of PoPH in PAH and that of PoPH in patients with liver cirrhosis, suggesting PoPH underdiagnosis and an incomplete understanding of this entity in the clinical setting. Specifically, real-world data in Japan is largely unknown as compared with in Europe and the United States. The present study aims to elucidate the prevalence and etiology of PoPH in Japanese patients with chronic liver disease.

METHODS AND DESIGN

In this prospective, single-center, observational investigation of PoPH patients with chronic liver disease, a targeted 2,500 Japanese adult patients regularly visiting Shinshu University Hospital in Matsumoto, Japan, for chronic liver disease will complete a standardized questionnaire on the presence of PoPH symptoms. If the respondent has signs of possible PoPH, ultrasound echocardiography (UCG) will be performed as a primary screening. In the case that UCG findings indicate pulmonary hypertension, the patient will be referred to a cardiologist for further evaluation, whereby a definitive diagnosis PoPH can be made. PoPH prevalence and etiology will be investigated at the time of diagnosis. Afterwards, patients with PoPH will be followed for five years for determination of survival rate.

DISCUSSION

This study will reveal the prevalence, etiology, and 5-year survival rate of PoPH in Japanese patients with chronic liver disease.

TRIAL REGISTRATION

This study is being performed at Shinshu University following registration as UMIN 000042287 on October 29, 2020.

Keeping Patients with End-Stage Liver Disease Alive While Awaiting Transplant: Management of Complications of Portal Hypertension

Complications of portal hypertension such as gastroesophageal variceal hemorrhage, ascites, and spontaneous bacterial peritonitis, as well as pulmonary complications, are often responsible for diminished quality of life, excess morbidity and mortality, increased health care resource use and expenditure, and dropout from the liver transplant (LT) waiting list. Therefore, the care of LT candidates on the waiting list must be centered on anticipation and prompt intervention for these complications.

Perioperative Right Ventricular Dysfunction: Analysis of Outcomes

Right ventricular dysfunction (RVD) is a well-known prognostic factor for adverse outcomes in cardiovascular medicine. The right ventricle (RV) in medically managed heart failure patients and in surgical patients perioperatively generally is overshadowed by left ventricular disease. However, with advancement of various diagnostic tools and better understanding of its functional anatomy, the role of the RV is emerging in many clinical conditions. The failure of one ventricle has significant effect on the function of the other ventricle and it is predominantly due to ventricular interdependence.¹ The etiology of RVD is multifactorial and irrespective of etiology. RVD has been associated with significant increases in morbidity and mortality in various clinical scenarios.^2,3 The primary objective of this comprehensive review is to analyze various etiology-related outcomes of RVD in the perioperative population.

Portopulmonary Hypertension: From Bench to Bedside

Portopulmonary hypertension (PoPH) is defined as pulmonary arterial hypertension (PAH) associated with portal hypertension and is a subset of Group 1 pulmonary hypertension (PH). PoPH is a cause of significant morbidity and mortality in patients with portal hypertension with or without liver disease. Significant strides in elucidating the pathogenesis, effective screening algorithms, accurate diagnoses, and treatment options have been made in past 20 years. Survival of PoPH has remained poor compared to IPAH and other forms of PAH. Recently, the first randomized controlled trial was done in this patient population and showed promising results with PAH specific therapy. Despite positive effects on hemodynamics and functional outcomes, it is unclear whether PAH specific therapy has a beneficial effect on long term survival or transplant outcomes. In this review, we will discuss the epidemiology, pathophysiology, clinical and hemodynamic characteristics of PoPH. Additionally, this review will highlight the lacunae in our current management strategy, challenges faced and will provide direction to potentially useful futuristic management strategies.

Pulmonary Complications in Patients with Liver Cirrhosis

Patients with advanced chronic liver diseases, particularly with decompensated liver cirrhosis, can develop specific pulmonary complications independently of any pre-existing lung disease. Especially when dyspnea occurs in combination with liver cirrhosis, patients should be evaluated for hepato-pulmonary syndrome (HPS), porto-pulmonary hypertension (PPHT), hepatic hydrothorax and spontaneous bacterial empyema, which represent the clinically most relevant pulmonary complications of liver cirrhosis. Importantly, the pathophysiology, clinical features, diagnosis and the corresponding therapeutic options differ between these entities, highlighting the role of specific diagnostics in patients with liver cirrhosis who present with dyspnea. Liver transplantation may offer a curative therapy, including selected cases of HPS and PPHT. In this review article, we summarize the pathogenesis, clinical features, diagnostic algorithms and treatment options of the 4 specific pulmonary complications in patients with liver cirrhosis.

Hepatopulmonary Syndrome and Portopulmonary Hypertension: Current Status and Implications for Liver Transplantation

PURPOSE OF REVIEW

Hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PoPH) are both pulmonary vascular complications of advanced liver disease; however, these syndromes have distinct pathophysiology, clinical implications, and management.

RECENT FINDINGS

While both conditions are associated with portal hypertension, HPS results from diffuse pulmonary capillary vasodilation and PoPH results from vasoconstriction and vascular remodeling of pulmonary arteries. In HPS, no medical therapies clearly improve outcomes; however, patients have excellent post-LT outcomes with near uniform reversal of hypoxemia. In PoPH, several medical therapies used in idiopathic pulmonary hypertension have been shown improve pulmonary hemodynamics, symptoms, and potentially LT outcomes; however, further study is needed to determine best treatment regimens, long-term outcomes on medical therapy, and role of LT.

SUMMARY

While HPS results in severe hypoxemia that is usually reversible by LT, PoPH patients develop progressive pulmonary hypertension that may improve with medical therapy.

Pulmonary manifestations of chronic liver disease: a comprehensive review

Hepatopulmonary syndrome (HPS) and porto-pulmonary hypertension (PoPH) represent relatively common pulmonary vascular complications of advanced liver disease. Despite distinct differences in their pathogenetic background, both clinical states are characterized by impaired arterial oxygenation and limited functional status, and are associated with increased pre-transplantation mortality. Accumulation of ascitic fluid in the pleural cavity, known as hepatic hydrothorax (HH), is another frequent manifestation of decompensated cirrhosis, which may cause severe respiratory dysfunction, depending on the volume of the effusion, the rapidity of its development and its resistance to therapeutic measures. Orthotopic liver transplantation constitutes the only effective treatment able to resolve the pulmonary complications of liver disease. A prioritization policy for liver transplantation has evolved over the past years regarding advanced stages of HPS, yielding favorable outcomes regarding post-transplantation survival and HPS resolution. In contrast, severe PoPH is associated with poor post-transplantation survival. Hence, liver transplantation is recommended only for patients with PoPH and an acceptable reduction in pulmonary pressure values, after receiving PoPH-targeted vasodilating therapy. This review focuses on basic pathogenetic and diagnostic principles and discusses the current therapeutic approaches regarding HPS, PoPH, and HH.

Pulmonary Complications of Portal Hypertension

The most common pulmonary complications of chronic liver disease are hepatic hydrothorax, hepatopulmonary syndrome, and portopulmonary hypertension. Hepatic hydrothorax is a transudative pleural effusion in a patient with cirrhosis and no evidence of underlying cardiopulmonary disease. Hepatic hydrothorax develops owing to the movement of ascitic fluid into the pleural space. Hepatopulmonary syndrome and portopulmonary hypertension are pathologically linked by the presence of portal hypertension; however, their pathophysiologic mechanisms are significantly different. Hepatopulmonary syndrome is characterized by low pulmonary vascular resistance secondary to intrapulmonary vascular dilatations and hypoxemia; portopulmonary hypertension features elevated pulmonary vascular resistance and constriction/obstruction within the pulmonary vasculature.

Portopulmonary Hypertension: A Complex Case Derived from Multiple Penetrating Trauma-Induced Mesenteric Arteriovenous Fistulae

Portopulmonary hypertension (PoPH) is a well-recognized complication of portal hypertension. This study reports a case of PoPH that was secondarily caused by post-traumatic mesenteric arteriovenous fistula. A 38-year-old man with a history of knife stabbing wounds in the abdomen in 2003 was admitted to the hospital with exertional shortness of breath and a mechanic murmur over the umbilical region. Computed tomography indicated signs of PoPH and mesenteric arteriovenous fistula. Percutaneous catheter-directed embolization was first performed but failed. Subsequently, the patient was successfully treated with fistula resection and partial enterectomy. The patient had been postoperatively followed regularly, and chief symptoms had been alleviated significantly and pulmonary pressure had successfully decreased to normal range. We believe that this is the first case of PoPH caused by mesenteric arteriovenous fistula.

The efficacy of serum brain natriuretic peptide for the early detection of portopulmonary hypertension in biliary atresia patients before liver transplantation

Severe portopulmonary hypertension (POPH) is a contraindication for liver transplantation (LT) because of the high risk of postoperative heart failure. The early detection of POPH is important for patients with biliary atresia (BA). Brain natriuretic peptide (BNP) is known to be correlated with liver fibrosis in patients with liver cirrhosis. The aim of this study was to elucidate the efficacy of BNP measurement for the follow-up of patients with BA. Thirty-two patients with BA were identified from September 2011 to December 2016. As indices of liver fibrosis/cirrhosis, APRI (P < .0001), FIB-4 (P < .0001), Child-Pugh score (P < .0001), IV collagen (P = .0005), and hyaluronic acid (P = .0291) had high or moderate correlations with BNP. Patients with splenomegaly, esophageal varices, liver fibrosis, and collateral veins had significantly higher BNP levels than those without. Patients diagnosed with POPH had significantly higher BNP levels in comparison with those patients without (P = .0068). In contrast, PELD/MELD scores showed an almost negligible correlation with the BNP level. LT was successful in 3 asymptomatic BA patients with POPH who had high BNP levels despite the low PELD/MELD scores. In conclusion, routine serum BNP surveillance can be easy to predict asymptomatic POPH. This may help to identify POPH before it reaches a stage that would contraindicate LT.

Perioperative management with phosphodiesterase type 5 inhibitor and prostaglandin E1 for moderate portopulmonary hypertension following adult-to-adult living-donor liver transplantation: a case report

Background

Portopulmonary hypertension (PPH) is a relatively rare but well-recognized complication of end-stage liver disease. Moderate or severe PPH (mean pulmonary artery pressure [mPAP] ≥ 35 mmHg) is usually a contraindication for liver transplantation due to high operation-related mortality. Here, we report on a patient with moderate PPH whose condition was successfully managed with a phosphodiesterase type 5 (PDE5) inhibitor (tadalafil) and prostaglandin E1, who experienced rapid improvement of PPH after living-donor liver transplantation (LDLT).

Case presentation

A 63-year-old woman with alcoholic decompensated cirrhosis was referred to our hospital for LDLT. She had mild dyspnea on exertion as well as fatigue. Echocardiography and subsequent cardiac catheterization revealed a high mPAP (35 mmHg), and she was diagnosed with moderate PPH. We commenced treatment with oral tadalafil for the PPH. A second preoperative echocardiography demonstrated improved PPH, and she underwent LDLT. An intravenous infusion of prostaglandin E1 was introduced instead of tadalafil during and after the operation.

The mPAP value showed a rapid decrease in mPAP value to 22 mmHg in 2 days. After discontinuation of the prostaglandin E1, the mPAP value remained 23 mmHg. Postoperative catheterization 2 months after LDLT showed no exacerbation of PPH. She was discharged on foot 70 days after LDLT in good condition and has shown a good clinical condition more than 2 years after LDLT.

Conclusion

LDLT could be a radical treatment for PPH with careful management and adequate patient selection. PDE5 inhibitor and PGE1 is effective and feasible for perioperative management of the patient with moderate portopulmonary hypertension in LDLT.

Anesthesia for Liver Transplantation

The provision of anesthesia for a liver transplant program requires a dedicated team of anesthesiologists. Liver transplant anesthesiologists must have an understanding of liver physiology and anatomy; the spectrum of clinical disease associated with liver dysfunction; the impact of warm and cold ischemia times, surgical techniques in liver transplantation, and the impact of ischemia-reperfusion syndrome; and optimal practices to protect the liver. The team must provide a 24-hour service, be actively involved in the selection committee process, and stay current with advances in the subspecialty.

Respiratory Complication in Liver Disease

Cirrhosis, the twelfth leading cause of death, accounts for 1.1% of all deaths in the United States. Although there are multiple pulmonary complications associated with liver disease, the most important complications that cause significant morbidity and mortality are hepatopulmonary syndrome, hepatic hydrothorax, and portopulmonary hypertension. Patients with cirrhosis who complain of dyspnea should be evaluated for these complications. This article reviews these complications.

International Liver Transplant Society Practice Guidelines: Diagnosis and Management of Hepatopulmonary Syndrome and Portopulmonary Hypertension

Two distinct pulmonary vascular disorders, hepatopulmonary syndrome (HPS) and portopulmonary hypertension (POPH) may occur as a consequence of hepatic parenchymal or vascular abnormalities. HPS and POPH have major clinical implications for liver transplantation. A European Respiratory Society Task Force on Pulmonary-Hepatic Disorders convened in 2002 to standardize the diagnosis and guide management of these disorders. These International Liver Transplant Society diagnostic and management guidelines are based on that task force consensus and should continue to evolve as clinical experience dictates. Based on a review of over 1000 published HPS and POPH articles identified via a MEDLINE search (1985-2015), clinical guidelines were based on, selected single care reports, small series, registries, databases, and expert opinion. The paucity of randomized, controlled trials in either of these disorders was noted. Guidelines are presented in 5 parts; I. Definitions/Diagnostic criteria; II. Hepatopulmonary syndrome; III. Portopulmonary hypertension; IV. Implications for liver transplantation; and V. Suggestions for future clinical research.

Current Approach to the Diagnosis and Management of Portopulmonary Hypertension

Portopulmonary hypertension (POPH) is a form of pulmonary arterial hypertension occurring in the setting of portal hypertension with or without hepatic cirrhosis. The presence of both portal and pulmonary vascular disease contributes to complicated hemodynamics and therapeutic challenges, though the severities do not appear to correlate directly. Diagnosis of POPH, and distinction from the commonly observed hyperdynamic state of end-stage liver disease, is typically accomplished with an initial screening transthoracic echocardiogram, followed by right heart catheterization for confirmation of hemodynamic parameters. Though few studies have directly evaluated use in POPH, pulmonary artery-directed therapy is the cornerstone of management, along with consideration of liver transplantation. Perioperative and long-term outcomes are variable, but uniformly worse in the setting of uncontrolled pulmonary pressures. Risk stratification and optimal patient selection for these interventions are areas of ongoing investigation.

Portopulmonary hypertension: Still an appropriate consideration for liver transplantation?

Liver transplantation (LT) in patients with portopulmonary hypertension (PoPH) has historically resulted in unpredictable and often poor outcomes. The United Kingdom experience for the period 1992-2012 is reported in this article. A retrospective analysis of patients, preoperatively fulfilling the PoPH European Respiratory Society Task Force on Pulmonary-Hepatic Vascular Disorders diagnostic criteria was conducted across all UK LT centers. Data collection included comorbidities, use of preoperative and postoperative pharmacotherapy, patient survival, and cause of death. To enable survival stratification, PoPH was classified as mild, moderate, or severe based on mean pulmonary pressure of <35 mm Hg, 35-49 mm Hg, and ≥50 mm Hg, respectively. Of 127 patients reported to have PoPH, just 28 fulfilled the diagnostic criteria (14 mild, 9 moderate, 5 severe). Twenty (71.4%) patients were male with median age and Model for End-Stage Liver Disease of 50 years (range, 23-62 years) and 18 (range, 6-43), respectively. Twelve (42.9%) patients died within 5 years of LT. The majority of deaths (10 of 12; 83%) occurred within the first 6 months after LT, aetiologies of which included right heart failure (n = 3), progressive PoPH (n = 2), and sepsis (n = 2). Of those receiving preoperative pharmacotherapy (n = 8), 5 are currently alive and were classified as mild to moderate PoPH. Both severe PoPH patients optimized preoperatively with pharmacotherapy died within a year of LT. Development of effective vasodilatory therapies in the setting of pulmonary arterial hypertension has led to a dramatic improvement in patient survival. The available data indicate that in this era of pharmacotherapy, PoPH in isolation no longer represents a valid consideration to transplant. Liver Transplantation 22 1637-1642 2016 AASLD.

Portopulmonary hypertension

Portopulmonary hypertension (PoPH) refers to the condition that pulmonary arterial hypertension (PAH) occur in the stetting of portal hypertension. The development of PoPH is thought to be independent of the severity of portal hypertension or the etiology or severity of liver disease. PoPH results from excessive vasoconstriction, vascular remodeling, and proliferative and thrombotic events within the pulmonary circulation that lead to progressive right ventricular failure and ultimately to death. Untreated PoPH is associated with a poor prognosis. As PoPH is frequently asymptomatic or symptoms are generally non-specific, patients should be actively screened for the presence of PoPH. Two-dimensional transthoracic echocardiography is a useful non-invasive screening tool, but a definitive diagnosis requires invasive hemodynamic confirmation by right heart catheterization. Despite a dearth of randomized, prospective data, an ever-expanding clinical experience shows that patients with PoPH benefit from therapy with PAH-specific medications including with endothelin receptor antagonists, phosphodiesterase-5 inhibitors, and/or prostanoids. Due to high perioperative mortality, transplantation should be avoided in those patients who have severe PoPH that is refractory to medical therapy.

Portopulmonary hypertension in liver transplant candidates

Pulmonary vascular disorders including portopulmonary hypertension (PoPHT) are among the common complications of liver disease and are prognostically significant. Survival is very low without medical treatment and liver transplantation. With advances in medical therapy for elevated pulmonary artery pressure (PAP) and liver transplant surgery, survival of patients with PoPHT and advanced liver disease is significantly improved. Because of the prognostic significance of PoPHT and the limited donor pool, a comprehensive preoperative cardio-pulmonary assessment is of great importance in cirrhotic patients prior to transplant surgery. Therefore, a detailed transthoracic Doppler echocardiographic examination must be an essential component of this evaluation. Patients with mild PoPHT can safely undergo liver transplant surgery. In cases of moderate to severe PoPHT, right heart catheterization (RHC) should be performed. In patients with moderate to severe PoPHT on RHC (mean PAP 35-45 mmHg), vasodilator therapy should be attempted. Liver transplantation should be encouraged in cases that demonstrate a positive response. Bridging therapy with specific pulmonary arterial hypertension treatment agents should be considered until the transplant surgery and should be continued during the peri- and post-operative periods as needed.

Portopulmonary Hypertension in Liver Disease Presenting in Childhood

OBJECTIVE

Portopulmonary hypertension (POPH) is a known complication of cirrhosis in adults, but there is little information on its incidence and outcome in children with liver disease. We report 14 patients with POPH and present a synthesis of the medical literature.

METHODS

Diagnosis of POPH in the 14 patients was based on right-sided heart catheterization displaying mean pulmonary artery pressure (mPAP) >25 mmHg, indexed pulmonary vascular resistances >3 Wood units · m, and pulmonary wedge pressure <15 mmHg. A literature review added 84 patients.

RESULTS

In our unit, POPH was found in 0.5% of the children with portal hypertension, 0.9% of the children with end-stage liver disease awaiting transplantation, and 3 children with congenital portosystemic shunts (CPSSs). Analysis of 98 reported patients, including the 14 presented here, showed the cause of liver disease to be chronic liver disease or portal cavernoma in 76 instances (34 with a history of surgical portosystemic shunt) and CPSS in 22 instances. There was a precession with proven hypoxemia caused by hepatopulmonary syndrome in 6 patients. Median survival was 3 months in 56 untreated patients. An 80% 5-year probability of survival in 42 patients was treated by CPSS closure, pulmonary vasodilators, and/or liver transplantation. Mean pretransplant mPAP was 34 and 49 mmHg in transplant survivors and nonsurvivors, respectively.

CONCLUSIONS

POPH is a rare but extremely severe complication of childhood liver disease. Portosystemic shunts, whether congenital or acquired, likely play an important causative role. Early diagnosis is crucial and requires systematic screening by echocardiography in children at risk.

2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension

Guidelines summarize and evaluate all available evidence on a particular issue at the time of the writing process, with the aim of assisting health professionals in selecting the best management strategies for an individual patient with a given condition, taking into account the impact on outcome, as well as the risk–benefit ratio of particular diagnostic or therapeutic means. Guidelines and recommendations should help health professionals to make decisions in their daily practice. However, the final decisions concerning an individual patient must be made by the responsible health professional(s) in consultation with the patient and caregiver as appropriate.

Successful Liver Transplant Complicated by Severe Portopulmonary Hypertension After an Initial Aborted Attempt: Case Report and Review of Treatment Options

Good right ventricular function and responsiveness to vasodilator therapy are the most important prerequisites for successful liver transplant in patients with portopulmonary hypertension. A patient with portopulmonary hypertension and good right ventricular function presented for deceased-donor liver transplant. Pulmonary arterial pressure was controlled with epoprostenol and sildenafil preoperatively. After anesthesia induction, pulmonary arterial pressure increased significantly and the procedure was aborted. Additional medical treatment included aggressive vasodilator therapy and the transplant was successfully performed 1 month later. During the procedure, elevations in pulmonary arterial pressure responded to a combination of inhaled nitric oxide, intravenous milrinone and nitroglycerin, and optimization of mechanical ventilation.

"Porto-pulmonary hypertension: a comprehensive review"

Porto-pulmonary hypertension (PoPH) is a rare but threatening vasculopathy, defined by the presence of pulmonary arterial hypertension (PAH) in the setting of portal hypertension. Although most commonly observed in cirrhotic patients, those with non-cirrhotic portal hypertension are also at risk of developing it. Little is known about the mechanisms by which PAH develop in patients with portal hypertension, but genetic factors, pulmonary vascular wall shear stress, and a dysregulation of vasoactive, proliferative and inflammatory mediators might be involved. PoPH is estimated to occur in 3 to 10% of patients with end-stage liver disease, although its frequency is not related to the severity of liver dysfunction or the degree of portal hypertension. Moderate-to-severe PoPH portends an extremely poor prognosis. Presentation is highly variable, therefore a high index of suspicion is required to establish the diagnosis. PoPH should be screened by transthoracic echocardiography (TTE) in cirrhotic patients presenting with dyspnoea as well as in all patients being evaluated for liver transplantation (LT) regardless of their symptoms. If TTE shows elevated pulmonary pressures, patients should undergo right heart catheterisation, which is required for the definitive diagnosis of PoPH. Without LT, the overall 5-year mortality in PoPH patients is 70%, but it should not be considered an indication for LT. Moderate-to-severe PoPH contraindicates LT, since it is associated with a prohibitively increased intra and postoperative mortality. However, there is now evidence supporting the use of PAH-specific therapies pre-LT in order to improve pulmonary haemodynamic measurements, so the procedure can then be performed with significantly lower risks.

Portopulmonary hypertension: an update

Portopulmonary hypertension represents a serious lung vascular disorder, defined as the presence of pulmonary arterial hypertension that is associated with portal hypertension, with or without the presence of significant liver disease. Transthoracic echocardiography represents the single best initial tool for the diagnostic evaluation in portopulmonary hypertension, and right heart catheterization remains the gold standard for definitive diagnosis. Despite the lack of randomized controlled trials in portopulmonary hypertension, some therapies have demonstrated improvements in cardiopulmonary haemodynamics and right ventricular function as described in case reports and case series. Specialists should be able to recognize indications and contraindications for liver transplantation in the setting of portopulmonary hypertension, and this review focuses on the appropriate diagnostic approach and current advances in medical therapies. Recognition of patients eligible for liver transplantation is needed to improve quality of life and survival.

Effectiveness of phosphodiesterase-5 inhibitor therapy for portopulmonary hypertension

BACKGROUND

Portopulmonary hypertension is associated with significant morbidity and mortality. Phosphodiesterase-5 inhibitor therapy is efficacious in other causes of WHO group I pulmonary arterial hypertension.

OBJECTIVE

To evaluate the efficacy and safety of phosphodiesterase-5 inhibitor therapy in patients with portopulmonary hypertension.

METHODS

A single-centre retrospective cohort study that included patients with a diagnosis of portopulmonary hypertension was performed. The primary outcome was change in pulmonary vascular resistance after six months of phosphodiesterase-5 inhibitor therapy. A secondary evaluation investigated the effect on other hemodynamic measurements, 6 min walk distance, functional class, safety outcomes and survival.

RESULTS

Of 1385 patients screened, 25 patients with portopulmonary hypertension were identified, of whom 20 received a phosphodiesterase-5 inhibitor. After six months, there was a significant decrease in pulmonary vascular resistance (-236 dyn • s • cm(-5) [95% CI -343 dyn • s • cm(-5) to -130 dyn • s • cm(-5)]; P<0.001), mean pulmonary artery pressure (-8.9 mmHg [95% CI -13.7 mmHg to -4.2 mmHg]; P=0.001) and an increase in Fick cardiac output (0.9 L/min [95% CI 0.1 L/min to 1.6 L/min]; P=0.02). There was no change in 6 min walk distance. The proportion of subjects with a WHO functional class III or IV was significantly reduced at six months compared with baseline (18% versus 61%; P=0.002). Safety outcomes did not reveal any adverse events.

CONCLUSIONS

Phosphodiesterase-5 inhibitor therapy improved hemodynamics and functional class at six months in a cohort of patients with portopulmonary hypertension.

Living-donor liver transplantation for congenital biliary atresia with porto-pulmonary hypertension and moderate or severe pulmonary arterial hypertension: Kyoto University experience

Porto-pulmonary hypertension with moderate or severe pulmonary arterial hypertension (PAH) is viewed as a contraindication to liver transplantation (LT) because of associated poor outcomes; however, patients with biliary atresia (BA) are generally good candidates for LT. Ten patients with moderate/severe PAH underwent living-donor liver transplantation (LDLT) at our institution; eight of these patients had BA and were the focus of this study. Preoperative therapies, including prostaglandin (PG)I2 , were introduced. When mean pulmonary arterial pressure (mPAP) after treatment was <40 mmHg or initial mPAP without therapy was <35 mmHg, we performed an acute volume challenge test to evaluate right ventricular function. LDLT was performed when mPAP after anesthetic induction was confirmed at ≤35 mmHg. Six patients had favorable responses to preoperative treatment and catheter testing, but two patients showed poor responses. The two patients with poor responses had poor clinical courses with unstable mPAP after LDLT. The other six patients had successful courses with well-controlled mPAP, and PGI2 was withdrawn or weaned following LDLT. Survival did not significantly differ between the eight BA recipients with moderate/severe PAH and 77 age-matched BA recipients without PAH from the same time period. LDLT has major benefits for BA patients with well-controlled PAH.

Portopulmonary hypertension

Portopulmonary hypertension (POPH) is the presence of pulmonary arterial hypertension in patients with portal hypertension. Among liver transplant (LT) candidates, reported incidence rates of POPH range from 4.5% to 8.5%. In patients with LT, intraoperative death and immediate post-LT mortality are feared clinical events when transplantation is attempted in the setting of untreated, moderate to severe POPH; therefore, POPH precludes LT unless the mean pulmonary artery pressure can be reduced to a safe level and right ventricular function optimized. Specific pulmonary artery vasodilator medications seem effective in reducing pulmonary artery pressures and improving right ventricular function and survival.

Clinical aspects of portopulmonary hypertension

Portopulmonary hypertension (PoPH) is an often neglected form of pulmonary hypertension where pulmonary hypertension occurs in the presence of portal hypertension. PoPH is important to diagnose and treat as it may improve the patient's quality of life and improve the outcome after liver transplantation. In this review, we discuss the clinical aspects of PoPH including its pathophysiology, diagnosis, treatment, and prognosis.

Pulmonary complications in chronic liver disease

The association of chronic liver disease with respiratory symptoms and hypoxia is well recognized. Over the last century, three pulmonary complications specific to chronic liver disease have been characterized: hepatopulmonary syndrome (HPS), portopulmonary hypertension (POPH), and hepatic hydrothorax (HH). The development of portal hypertension is fundamental in the pathogenesis of each of these disorders. HPS is the most common condition, found in 5%-30% of cirrhosis patients, manifested by abnormal oxygenation due to the development of intrapulmonary vascular dilatations. The presence of HPS increases mortality and impairs quality of life, but is reversible with liver transplantation (LT). POPH is characterized by development of pulmonary arterial hypertension in the setting of portal hypertension, and is present in 5%-10% of cirrhosis patients evaluated for LT. Screening for POPH in cirrhosis patients eligible for LT is critical since severe POPH is a relative contraindication for LT. Patients with moderate POPH, who respond adequately to medical therapy, may benefit from LT, although sufficient controlled data are lacking. HH is a transudative pleural effusion seen in 5%-10% of cirrhosis patients, in the absence of cardiopulmonary disease. Diagnosis of HH should prompt consideration for LT, which is the ultimate treatment for HH. Conservative management includes salt restriction and diuretics, with thoracentesis and transjugular intrahepatic portosystemic shunt (TIPS) as second-line therapeutic options.