Pulmonary hypertension complicating portal hypertension: prevalence and relation to splanchnic hemodynamics

Hepatopulmonary syndrome and portopulmonary hypertension

Hepatopulmonary syndrome and portopulmonary hypertension are 2 of many diseases that affect the lungs in patients with liver disease. The 2 vascular conditions are often confused. We review both hepatopulmonary syndrome and portopulmonary hypertension to better understand their pathophysiologies, clinical presentations, tools to aid in differentiating and diagnosing the disease states, treatment options, and influences on patient prognosis. We also consider patient viability for liver transplantation.

Pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a chronic and progressive disease leading to right heart failure and ultimately death if untreated. The first classification of PH was proposed in 1973. In 2008, the fourth World Symposium on PH held in Dana Point (California, USA) revised previous classifications. Currently, PH is devided into five subgroups. Group 1 includes patients suffering from idiopathic or familial PAH with or without germline mutations. Patients with a diagnosis of PAH should systematically been screened regarding to underlying mutations of BMPR2 gene (bone morphogenetic protein receptor type 2) or more rarely of ACVRL1 (activine receptor-like kinase type 1), ENG (endogline) or Smad8 genes. Pulmonary veno occusive disease and pulmonary capillary hemagiomatosis are individualized and designated as clinical group 1'. Group 2 'Pulmonary hypertension due to left heart diseases' is divided into three sub-groups: systolic dysfonction, diastolic dysfonction and valvular dysfonction. Group 3 'Pulmonary hypertension due to respiratory diseases' includes a heterogenous subgroup of respiratory diseases like PH due to pulmonary fibrosis, COPD, lung emphysema or interstitial lung disease for exemple. Group 4 includes chronic thromboembolic pulmonary hypertension without any distinction of proximal or distal forms. Group 5 regroup PH patients with unclear multifactorial mechanisms. Invasive hemodynamic assessment with right heart catheterization is requested to confirm the definite diagnosis of PH showing a resting mean pulmonary artery pressure (mPAP) of ≥ 25 mmHg and a normal pulmonary capillary wedge pressure (PCWP) of ≤ 15 mmHg. The assessment of PCWP may allow the distinction between pre-capillary and post-capillary PH (PCWP > 15 mmHg). Echocardiography is an important tool in the management of patients with underlying suspicion of PH. The European Society of Cardiology and the European Respiratory Society (ESC-ERS) guidelines specify its role, essentially in the screening proposing criteria for estimating the presence of PH mainly based on tricuspid regurgitation peak velocity and systolic artery pressure (sPAP). The therapy of PAH consists of non-specific drugs including oral anticoagulation and diuretics as well as PAH specific therapy. Diuretics are one of the most important treatment in the setting of PH because right heart failure leads to fluid retention, hepatic congestion, ascites and peripheral edema. Current recommendations propose oral anticoagulation aiming for targeting an International Normalized Ratio (INR) between 1.5-2.5. Target INR for patients displaying chronic thromboembolic PH is between 2–3. Better understanding in pathophysiological mechanisms of PH over the past quarter of a century has led to the development of medical therapeutics, even though no cure for PAH exists. Several specific therapeutic agents were developed for the medical management of PAH including prostanoids (epoprostenol, trepoprostenil, iloprost), endothelin receptor antagonists (bosentan, ambrisentan) and phosphodiesterase type 5 inhibitors (sildenafil, tadalafil). This review discusses the current state of art regarding to epidemiologic aspects of PH, diagnostic approaches and the current classification of PH. In addition, currently available specific PAH therapy is discussed as well as future treatments.

Parenchymal alterations in cirrhotic livers in patients with hepatopulmonary syndrome or portopulmonary hypertension

Hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPH) are distinct pulmonary vascular complications of cirrhosis. Little is known about possible associated hepatic histopathological features. Explanted livers from patients clinically diagnosed with HPS (n = 8) or PPH (n = 7) and cirrhotic explants from controls (n = 30) without HPS or PPH were evaluated with trichrome histochemistry, anti-glutamine synthetase (anti-GS), and anti-CD34 immunohistochemistry (IHC). Trichrome stains were characterized by cirrhotic nodules (CNs) of various sizes, including incomplete septal cirrhosis (ISC). ISC was overrepresented in the HPS (4/8 or 50%) and PPH livers (3/7 or 43%); in addition, neither group had micronodular cirrhosis. The control explants showed the entire spectrum of nodules: micronodular, macronodular, mixed CNs, and ISC (P = 0.04). The variability of cirrhosis severity was shown with the Laennec grading system (0-6). The cirrhosis of the majority of the HPS (6/8) and PPH livers (6/7) was scored as mild, whereas the control explants were more evenly distributed across the mild (14/30) and moderate/severe grades (16/30). GS positivity was retained in a perivenular location as the dominant pattern in each explant group. CD34 staining detected capillarized sinusoids of CNs as well as vascular channels within septa, but no significant differences were found between the groups. None of the observed light microscopy or histochemistry and IHC patterns showed a correlation with the underlying liver disease. Although our results demonstrate variable architectural and vascular remodeling within and between explant livers regardless of the presence or types of pulmonary complications, there were differences in explants with HPS or PPH versus controls that correlated with less severe cirrhosis.

Living-donor liver transplantation for moderate or severe porto-pulmonary hypertension accompanied by pulmonary arterial hypertension: a single-centre experience over 2 decades in Japan

BACKGROUND

Candidates for orthotopic liver transplantation (OLT) often have porto-pulmonary hypertension (PPHTN) with pulmonary arterial hypertension (PAH). Poor outcomes of PPHTN contraindicate OLT. There are no guidelines for living-donor liver transplantation (LDLT) in PPHTN patients.

METHODS

We present our experiences of LDLT in six patients with moderate or severe PPHTN, along with our institutional guidelines. Three had liver cirrhosis and three were non-cirrhotic. Catheterization studies were undertaken before, during and after LDLT, and the mean pulmonary arterial pressure (mPAP), cardiac output (CO), pulmonary vascular resistance and total peripheral resistance (TPR) were monitored.

RESULTS

The results showed significant differences in CO and TPR between cirrhotic and non-cirrhotic patients before, during and after LDLT. Cirrhotic patients showed systemic hyperdynamic state. Two cirrhotic patients showed poor responses to pre-transplant treatment, and continued to have increased PAH and poor clinical courses after LDLT. LDLT has an advantage of flexible timing of LT. Currently in our institution, PPHTN patients with mPAP <40 mmHg are registered for LDLT after treatment and catheterization. However, LDLT is performed when mPAP is ≤35 mmHg, leading to improved outcomes.

CONCLUSION

PPHTN patients with well-controlled PAH, or secondary PAH resulting from porto-systemic shunts, may be appropriate candidates for LDLT after careful considerations.

Austrian consensus on the definition and treatment of portal hypertension and its complications (Billroth II)

In November 2004, the Austrian Society of Gastroenterology and Hepatology (ÖGGH) held for the first time a consensus meeting on the definitions and treatment of portal hypertension and its complications in the Billroth-Haus in Vienna, Austria (Billroth I-Meeting). This meeting was preceded by a meeting of international experts on portal hypertension with some of the proponents of the Baveno consensus conferences (http://www.oeggh.at/videos.asp). The consensus itself is based on the Baveno III consensus with regard to portal hypertensive bleeding and the suggestions of the International Ascites Club regarding the treatment of ascites. Those statements were modified by new knowledge derived from the recent literature and also by the current practice of medicine as agreed upon by the participants of the consensus meeting. In October 2011, the ÖGGH organized the second consensus meeting on portal hypertension and its complications in Vienna (Billroth II-Meeting). The Billroth II-Guidelines on the definitions and treatment of portal hypertension and its complications take into account the developments of the last 7 years, including the Baveno-V update and several key publications.

Pulmonary vascular complications in portal hypertension and liver disease: a concise review

Chronic liver disease and/or portal hypertension may be associated with one of the two pulmonary vascular complications: portopulmonary hypertension and hepatopulmonary syndrome. These pulmonary vascular disorders are notoriously underdiagnosed; however, they have a substantial negative impact on survival and require special attention in order to understand their diagnostic approach and to select the best therapeutic options. Portopulmonary hypertension 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. On the other hand, abnormal intrapulmonary vascular dilations, profound hypoxemia, and a wide alveolar-arterial gradient are the hallmarks of the hepatopulmonary syndrome, resulting in difficult-to-treat hypoxemia. The aim of this review is to summarize the latest pathophysiologic concepts, diagnostic approach, therapy, and prognosis of portopulmonary hypertension and hepatopulmonary syndrome, as well as to discuss the role of liver transplantation as a definitive therapy in selected patients with these conditions.

Portopulmonary hypertension in cirrhotic patients: Prevalence, clinical features and risk factors

The incidence and clinical features of portopulmonary hypertension (POPH) have not been adequately described and it is currently unknown whether an association exists between the severity of POPH and liver function. Additionally, POPH risk factors are yet to be identified. The aim of this study was to determine the prevalence, describe the clinical features and investigate the potential risk factors of POPH. We conducted a study of 100 cirrhotic patients hospitalized between March 2011 and May 2012 at Tongji Hospital in Shanghai. The clinical characteristics of patients with and without POPH were analyzed. Clinical variables with a possible association with POPH were measured and pulmonary artery systolic pressure (PASP) was determined by cardiac Doppler echocardiography. Of the 100 patients enrolled in this study, 10 were diagnosed with POPH. Seven of the cases were mild, two were moderate and only one was severe; eight were attributed to viral infections. POPH was not detected in patients with schistosomal or alcoholic cirrhosis. Hemoglobin (Hb) levels were lower in patients with POPH compared to those without POPH (P<0.01) and the severity of POPH was not significantly correlated with Child-Pugh grade (R=−0.06, P=0.09). Hb levels, incidence of hepatitis C virus (HCV) infection and portal vein thrombosis differed between the two groups (P<0.05). Hb levels were identified as an independent risk factor associated with POPH and portal vein thrombosis may play an important role during the development of POPH. However, the severity of POPH was not associated with liver function.

Preoperative Assessment and Management of Liver Transplant Candidates With Portopulmonary Hypertension

Pulmonary artery hypertension (PAH) that occurs as a consequence of portal hypertension is termed portopulmonary hypertension (POPH) and is associated with significant morbidity and mortality. Among liver transplant (LT) candidates, reported incidence rates of POPH range from 4.5% to 8.5%. The severity of POPH is unrelated to the severity of portal hypertension or the liver disease. In LT patients, intraoperative death and immediate post-LT mortality are feared clinical events when transplantation is attempted in the setting of untreated, moderate to severe POPH. Specific pulmonary artery vasodilator medications (PAH-specific therapy) appear effective in reducing pulmonary artery pressures, improving right ventricular (RV) function and survival. Thus, screening for and accurately diagnosing POPH prior to LT has become a standard of care. The post-LT course of patients with moderate POPH is unpredictable, but most patients can be weaned from PAH-specific therapy over time. In this article, we present an overview of the preoperative assessment of POPH with an emphasis on risk assessment for transplant and the most recent medical treatment options.

Review article: liver transplantation for the pulmonary disorders of portal hypertension

BACKGROUND

Liver transplantation is potentially a life-saving therapeutic intervention for patients with portopulmonary hypertension and hepatopulmonary syndrome. However, due to limited data, listing criteria for patients with these conditions have not been clearly established. Indeed, this has led some to speculate that transplantation may not be appropriate in cases of moderate-to-severe portopulmonary hypertension and severe hepatopulmonary syndrome.

AIM

To critically discuss the utility of LT for the treatment of hepatopulmonary syndrome and portopulmonary hypertension.

METHODS

A literature search was conducted in 2012 on PubMed, Ovid Embase, Ovid Medline and Scopus using the following search terms: hepatopulmonary syndrome, portopulmonary hypertension, pulmonary arterial hypertension, liver transplantation. Relevant manuscripts were included in the review.

RESULTS

Liver transplantation has established itself as an effective treatment for selected patients with hepatopulmonary syndrome and portopulmonary hypertension. A multidisciplinary team approach incorporating focused strategies (both pre- and post-operatively) aimed at improving oxygenation in patients with hepatopulmonary syndrome has led to a dramatic improvement in patient outcomes. Additionally, careful patient selection and the use of targeted pulmonary vascular therapies are successfully being used to treat portopulmonary hypertension and 'bridge' patients to successful liver transplantation.

CONCLUSIONS

Liver transplantation is an effective therapy for patients with hepatopulmonary syndrome and portopulmonary hypertension. However, rigorous screening and early identification of these conditions allied with aggressive pre-operative optimisation of physiology and diligent post-operative care are imperative to ensuring a good outcome.

Pulmonary hypertension in CKD

Pulmonary arterial hypertension is a rare disease often associated with positive antinuclear antibody and high mortality. Pulmonary hypertension, which rarely is severe, occurs frequently in patients with chronic kidney disease (CKD). The prevalence of pulmonary hypertension ranges from 9%-39% in individuals with stage 5 CKD, 18.8%-68.8% in hemodialysis patients, and 0%-42% in patients on peritoneal dialysis therapy. No epidemiologic data are available yet for earlier stages of CKD. Pulmonary hypertension in patients with CKD may be induced and/or aggravated by left ventricular disorders and risk factors typical of CKD, including volume overload, an arteriovenous fistula, sleep-disordered breathing, exposure to dialysis membranes, endothelial dysfunction, vascular calcification and stiffening, and severe anemia. No specific intervention trial aimed at reducing pulmonary hypertension in patients with CKD has been performed to date. Correcting volume overload and treating left ventricular disorders are factors of paramount importance for relieving pulmonary hypertension in patients with CKD. Preventing pulmonary hypertension in this population is crucial because even kidney transplantation may not reverse the high mortality associated with established pulmonary hypertension.

Classification of pulmonary hypertension

Pulmonary hypertension (PH) can develop in association with many different diseases and risk factors, and its presence is nearly always associated with reduced survival. The prognosis and management of PH is largely dependent upon its underlying etiology and severity of disease. The combination of clinical and hemodynamic classifications of PH provides a framework for the diagnostic evaluation of PH to establish a final clinical diagnosis that guides therapy. As our understanding of the different pathologic mechanisms that underlie the syndrome of PH evolves, so too will the classification and treatment of PH.

Pulmonary vascular complications of liver disease

Hepatopulmonary syndrome and portopulmonary hypertension are two pulmonary vascular complications of liver disease. The pathophysiology underlying each disorder is distinct, but patients with either condition may be limited by dyspnea. A careful evaluation of concomitant symptoms, the physical examination, pulmonary function testing and arterial blood gas analysis, and echocardiographic, imaging, and hemodynamic studies is crucial to establishing (and distinguishing) these diagnoses. Our understanding of the pathobiology, natural history, and treatment of these disorders has advanced considerably over the past decade; however, the presence of either still increases the risk of morbidity and mortality in patients with underlying liver disease. There is no effective medical treatment for hepatopulmonary syndrome. Although liver transplantation can resolve hepatopulmonary syndrome, there appears to be worse survival even with transplantation. Liver transplantation poses a very high risk of death in those with significant portopulmonary hypertension, where targeted medical therapies may improve functional status and allow successful transplantation in a small number of select patients.

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.

Diagnostic dilemmas in pulmonary hypertension

Dilemmas persist in the screening, assessment, and follow-up of patients with pulmonary hypertension, relating to issues of whom and how to screen, how to resolve ambiguities in the clinical classification of patients with multiple potential substrates of pulmonary vascular disease, how to interpret test results, how to integrate multiple clinical parameters into a global diagnosis, how to use ambiguous test results, how to determine disease severity and prognosis, and how to monitor patients on treatment. This article describes how to incorporate available information into the diagnostic process, and where lack of concrete data should impose caution in patient management.

Treatment with sildenafil and treprostinil allows successful liver transplantation of patients with moderate to severe portopulmonary hypertension

Portopulmonary hypertension (PoPH) refers to pulmonary arterial hypertension associated with portal hypertension with or without evidence of an underlying liver disease. Despite the potential for curing PoPH with liver transplantation, the presence of moderate or severe PoPH is associated with increased morbidity and mortality and is, therefore, a contraindication to transplantation. Previous studies have predominantly used intravenous epoprostenol for treatment in order to qualify patients for liver transplantation. In this retrospective case series, we describe the clinical course of 11 patients whom we successfully treated (predominantly with oral sildenafil and subcutaneous treprostinil) in order to qualify them for liver transplantation. The mean pulmonary artery pressure significantly improved from 44 to 32.9 mm Hg, and the pulmonary vascular resistance decreased from 431 to 173 dyn second cm(-5) . There were significant improvements in the cardiac output and the transpulmonary gradient with these therapies as well. All 11 patients subsequently received liver transplants with a 0% mortality rate to date; the duration of follow-up ranged from 7 to 60 months. After transplantation, 7 of the 11 patients (64%) were off all pulmonary vasodilators, and only 2 patients required transiently increased doses of prostacyclins. In conclusion, an aggressive approach to the treatment of PoPH with sildenafil and/or treprostinil and subsequent liver transplantation may be curative for PoPH in some patients.

Prevalence of spontaneous portosystemic shunts in patients with portopulmonary hypertension and effect on treatment

BACKGROUND & AIMS

We documented the frequency of large spontaneous portosystemic shunts in patients with moderate or severe portopulmonary hypertension (POPH) and determined the association between large shunts and response to treatment.

METHODS

We performed a retrospective case-control study of data from patients with mild (mean pulmonary artery pressure [MPAP], 25-35 mm Hg; n = 18), moderate (MPAP, 35-50 mm Hg; n = 45), and severe POPH (MPAP, >50 mm Hg; n = 16). Data were compared with those from controls (normal echocardiography with estimated right ventricular systolic pressure, <35 mm Hg; n = 122). Spontaneous portosystemic shunts greater than 10 mm in diameter, identified by computed tomography or magnetic resonance, were classified as large. Response to treatment at 6 months was defined by right ventricular systolic pressure or MPAP as significant (<35 mm Hg), partial (35-50 mm Hg), or no response (>50 mm Hg).

RESULTS

The frequency of spontaneous shunts did not differ significantly between groups of subjects with severe (n = 14 of 16), moderate (n = 38 of 45), or mild POPH (n = 11 of 18) or normal echocardiograms (controls, n = 86 of 122) (P = .77). Large shunts were associated with severe (14 of 16) and moderate POPH (32 of 45), compared with mild POPH (6 of 18) or controls (30 of 122) (P < .01). In 13 patients with severe POPH, large shunts were associated with lack of response to treatment in 90% (8 of 9) or partial response in 50% (2 of 4). Among 27 patients with moderate POPH, large shunts were associated with no response to treatment in 13 of 19 (68%) and a partial response in 2 of 6 (33%).

CONCLUSIONS

Large spontaneous portosystemic shunts are associated significantly with moderate and severe POPH, and with lack of response to treatment.

Model for end-stage liver disease exceptions in the context of the French model for end-stage liver disease score-based liver allocation system

Model for End-Stage Liver Disease (MELD) score-based allocation systems have been adopted by most countries in Europe and North America. Indeed, the MELD score is a robust marker of early mortality for patients with cirrhosis. Except for extreme values, high pretransplant MELD scores do not significantly affect posttransplant survival. The MELD score can be used to optimize the allocation of allografts according to a sickest first policy. Most often, patients with small hepatocellular carcinomas (HCCs) and low MELD scores receive extra points, which allow them appropriate access to transplantation comparable to the access of patients with advanced cirrhosis and high MELD scores. In addition to patients with advanced cirrhosis and HCC, patients with a number of relatively uncommon conditions have low MELD scores and a poor prognosis in the short term without transplantation but derive excellent benefits from transplantation. These conditions, which correspond to the so-called MELD score exceptions, justify the allocation of a specific score for appropriate access to transplantation. Here we report the conclusions of the French consensus meeting. The goals of this meeting were (1) to identify which conditions merit MELD score exceptions, (2) to list the criteria needed for defining each of these conditions, and (3) to define a reasonable time interval for organ allocation for each MELD exception in the general context of organ shortages. MELD exceptions were discussed in an attempt to reconcile the concepts of transparency, equity, justice, and utility.

Critical care management of patients with end-stage liver disease

OBJECTIVES

To review the management of complications related to end-stage liver disease in the intensive care unit. The goal of this review is to address topics important to the practicing physician.

DATA SOURCES

We performed an organ system-based PubMed literature review focusing on the diagnosis and treatment of critical complications of end-stage liver disease. DATA SYNTHESIS AND FINDINGS: When available, preferential consideration was given to randomized controlled trials. In the absence of trials, observational and retrospective studies and consensus opinions were included. We present our recommendations for the neurologic, cardiovascular, pulmonary, gastrointestinal, renal, and infectious complications of end-stage liver disease.

CONCLUSIONS

Complications related to end-stage liver disease have significant morbidity and mortality. Management of these complications in the intensive care unit requires awareness and expertise among physicians from a wide variety of fields.

Portopulmonary hypertension and serum endothelin levels in hospitalized patients with cirrhosis

BACKGROUND

Cirrhosis is associated with several extrahepatic manifestations including portopulmonary hypertension (PPHT). Recent data suggest that endothelins (ETs) are related to the pathophysiology of PPHT. The study aimed to measure serum ET levels in hospitalized cirrhotic patients and to determine their association with PPHT and patient outcome.

METHODS

Fifty-seven cirrhotic patients [43 males; median age 58 (28-87) years] underwent Doppler echocardiography. Patients with systolic pulmonary arterial pressure ≥40 mmHg and pulmonary acceleration time <100 ms were deemed to have PPHT. ET-1, 2, and 3 serum levels were measured with an ELISA assay. All-cause mortality was recorded over a median period of 24 months.

RESULTS

Nine out of 57 patients (15.8%) had PPHT. Among various clinical variables, only autoimmune hepatitis was associated with PPHT (OR=11.5; 95% CI, 1.58-83.4; P=0.01). ET-1 levels [9.1 (1.6-20.7) vs 2.5 (1.4-9.2) pg/mL, P=0.02] and the ET-1/ET-3 ratio [4.73 (0.9-22.4) vs 1.6 (0.3-10.7), P=0.02] were significantly higher in patients with PPHT than in those without. ET-2 and ET-3 levels did not differ between the two groups. There was no difference in survival between the two groups, although ET-1 levels were associated with an adverse outcome in Cox regression analysis (HR=1.11; 95% CI, 1.02-1.22; P=0.02 per unit increase in ET-1).

CONCLUSION

Our data suggest that ET-1 and the ET-1/ET-3 ratio are elevated in patients with PPHT and that ET-1 is associated with a poor outcome irrespective of PPHT.

Portopulmonary hypertension: a report from the US-based REVEAL Registry

BACKGROUND

We evaluated survival and hospitalization rates in patients with group 1 portopulmonary hypertension (PoPH) in the Registry to Evaluate Early and Long-term Pulmonary Arterial Hypertension Disease Management (REVEAL Registry).

METHODS

The REVEAL Registry is a multicenter, observational, US-based study evaluating demographics and management of patients with pulmonary arterial hypertension (PAH). Outcomes were examined using Kaplan-Meier time-to-event estimates and compared with patients with idiopathic PAH (IPAH) or familial PAH (FPAH).

RESULTS

One hundred seventy-four patients with PoPH were enrolled in the REVEAL Registry (IPAH/FPAH; n = 1,478) from March 2006 to December 2009. Mean age was 53 ± 10 years, 52% were female, 32% were newly diagnosed, and 6% were New York Heart Association/World Health Organization functional class IV. Outcome parameters were worse for PoPH vs IPAH/FPAH, respectively: 2-year survival from enrollment (67% vs 85%, P < .001), 5-year survival from time of diagnosis (40% vs 64%, P < .001), and 2-year freedom from all-cause hospitalization (49% vs 59%, P = .019). However, despite worse outcomes, hemodynamic parameters at diagnosis were better for PoPH vs IPAH/FPAH, respectively: mean pulmonary artery pressure (49 mm Hg vs 53 mm Hg, P < .001), mean right atrial pressure (9 mm Hg vs 10 mm Hg, P = .005), pulmonary vascular resistance (8 Wood units vs 12 Wood units, P < .001), and cardiac output (5 L/min vs 4 L/min, P < .001). Compared with patients with IPAH/FPAH, patients with PoPH were less likely to be on a PAH-specific therapy at enrollment (P < .001), suggesting potential delays in therapy for patients with PoPH.

CONCLUSIONS

Patients with PoPH had significantly poorer survival and all-cause hospitalization rates compared with patients with IPAH/FPAH, despite having better hemodynamics at diagnosis. Further studies should investigate such outcomes and differences in treatment patterns.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00370214; URL: www.clinicaltrials.gov.

Management of cardiopulmonary complications of cirrhosis

Advanced portal hypertension accompanying end-stage liver disease results in an altered milieu due to inadequate detoxification of blood from splanchnic circulation by the failing liver. The portosystemic shunts with hepatic dysfunction result in an increased absorption and impaired neutralisation of the gastrointestinal bacteria and endotoxins leads to altered homeostasis with multiorgan dysfunction. The important cardiopulmonary complications are cirrhotic cardiomyopathy, hepatopulmonary syndrome, portopulmonary hypertension, and right-sided hydrothorax.

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.

Portopulmonary hypertension: challenges in diagnosis and management

Portopulmonary hypertension is defined as the combination of pulmonary arterial hypertension with portal hypertension and presents management complications in patients awaiting liver transplantation. The combination of these vascular disorders has a marked impact on mortality. At present the recommendations for management are limited because of the paucity of definitive clinical trials. We have reviewed the available data on prevalence, diagnosis and treatment. It is clearly time to more formally approach the study of this patient population.

Portopulmonary hypertension

Portopulmoanry hypertension (POPH) is a form of pulmonary arterial hypertension (PAH) associated with portal hypertension with or without underlying chronic liver disease. POPH is increasingly recognized and recent evidence suggests that it is one of the leading causes of PAH. The pathophysiology of POPH is poorly understood although the pathological changes in pulmonary vasculature in advanced POPH are similar to those seen in idiopathic pulmonary hypertension. The prognosis in patients with liver disease who also suffer from significant POPH is considered to be poor. Higher degree of pulmonary artery pressure (PAP) may preclude a patient from liver transplant as mortality in these patients is high. The treatment with vasodilator therapy has shown to improve both hemodynamics and clinical outcome in POPH in retrospective studies and in some case series. The aim of medical management is to bring PAP <35 mmHg that may make a patient with POPH and advanced liver disease eligible for liver transplant, which otherwise would have been denied because of high PAP.

[Perioperative anesthesia management of extended partial liver resection. Pathophysiology of hepatic diseases and functional signs of hepatic failure]

The importance of partial liver resection as a therapeutic option to cure hepatic tumors has increased over the last decades. This has been influenced on the one hand by advances in surgical and anesthetic management resulting in a reduced mortality after surgery and on the other hand by an increased incidence of hepatocellular carcinoma. Nowadays, partial resection of the liver is performed safely and as a routine operation in specialized centers. This article describes the pathophysiological changes secondary to liver failure and assesses the perioperative management of patients undergoing partial or extended liver resection. It looks in detail at the preoperative assessment, the intraoperative anesthetic management including fluid management and techniques to reduce blood loss as well as postoperative analgesia and intensive care therapy.

The heart in liver transplantation

The heart and liver are organs that are closely related in both health and disease. Patients who undergo liver transplantation may suffer from heart disease that is: (a) related to the original cause of the liver disease such as hemochromatosis, (b) related to the liver disease itself, or (c) related to other associated conditions. Furthermore, liver transplantation is one of the most cardiovascular stressful events that a patient with cirrhosis may undergo. After liver transplantation, the progression of pre-existing or the development of new-onset cardiac disease may occur. This article reviews the relationship between the heart and liver transplantation in the pre-transplant, intra-operative, and post-transplant periods.

Intensivtherapie nach Transplantation solider Organe

Der Intensivmedizin kommt eine zentrale Bedeutung in Rahmen der Transplantationsmedizin zu. Aufgrund ihrer marginalen Organfunktion benötigen die Patienten nicht selten bereits im Vorfeld der Transplantation eine intensivmedizinische Versorgung, zu der dann auch die Evaluation und Listung sowie die Koordination des zeitkritischen Transplantationsablaufs gehören können. Die direkte postoperative Betreuung nach komplexen Organtransplantationen bedarf fast ausschließlich der Versorgung im Rahmen von Überwachungsstationen, in denen sowohl direkt transplantationsassoziierte Komplikationen als auch Nebenerkrankungen eine intensivmedizinische Behandlungen notwendig machen. Sie zielt auf die Stabilisierung der Organfunktion, Behandlung begleitender Organdysfunktionen, adäquate Induktion der Immunsuppression und die möglichst frühe Wiedererlangung der Eigenständigkeit des Transplantierten ab.

[Pulmonary affection in advanced liver disease - hepatepulonary syndrome and portopulmonary hypertension]

Patients suffering from severe chronic liver disease, in particular cirrhosis, are at risk for pulmonary complications. The leading clinical symptom is shortness of breath, which can accompany the actual disease as indirect effect because of anemia, faint muscles or ascites. On the other hand, dyspnea can have multiple additive causes in case of accompanying cardial or pulmonary disease. The hepatopulmonary syndrome (HPS) and the portopulmonary hypertension (PoPH) belong to the most relevant pulmonary complications in liver cirrhosis. HPS appears to be more common than PoPH and the presence of either entity increases morbidity and mortality in patients with liver disease. The two diseases have to be strictly distinguished, as they have opposed histological and pathophysiological origin. While the HPS is a dilatative pulmonary- vascular disease, the PoPH is a constrictive or obliterative pulmonary-vascular disease in the context of a liver disease or a portal hypertension. Therefore, these diseases are separate entities also when it comes to diagnostics and therapy.

[Intensive therapy after solid organ transplantation]

Transplantation medicine is an interdisciplinary task and the priority objective is a fast recovery to patient independence. After kidney transplantation the crucial aims are monitoring of transplant perfusion, maintainance of an adequate volume status and avoidance of nephrotoxic medications. Transplantation for patients with advanced chronic liver failure has become more common since the implementation of the model of end stage liver disease (MELD) allocation system which is associated with more complicated proceedings. The essentials of critical care after liver transplantation are monitoring of transplant function, diagnosis of perfusion or biliary tract problems, specific substitution of coagulation factors and hemodynamic optimation due to avoidance of hepatic congestion. Many patients listed for heart transplantation need preoperative intensive care due to impaired heart function. Postoperatively a specific cardiac support with pulmonary arterial dilatators and inotropics is usually necessary. Lung transplantation aims at an improvement of patient quality of life. Postoperative critical care should provide a limitation of the pulmonary arterial pressure, avoidance of volume overload and rapid weaning from the respirator.

Plasma Cytokines and Portopulmonary Hypertension in Patients With Cirrhosis Waiting for Orthotopic Liver Transplantation

Portopulmonary hypertension (PPHTN) is a rare complication in patients with portal hypertension. A role of endothelin 1 (ET-1) and other cytokines was demonstrated in primary pulmonary hypertension but not in PPHTN. We evaluated the possible role of ET-1, interleukin 6 (IL-6), interleukin 1β (IL-1β), and tumor necrosis factor alpha (TNF-α) in the pathogenesis of PPHTN. Plasmatic concentrations of ET-1, IL-6, IL-1β, and TNF-α were measured in patients with pulmonary systolic arterial pressure (PAPs) >30 mm Hg and in patients with cirrhosis. In all, Six out of 11 patients with PAPs >30 mm Hg had PPHTN on right heart catheterization. The remaining 10 patients had an hyperdynamic circulation (HC). In PPHTN patients, ET-1 and IL-6 were significantly higher compared with HC and patients with cirrhosis. Endothelin 1 and IL-6 could be implicated in the pathogenesis of PPHTN. On the basis of these results, ET-1 receptor antagonists or anti-IL-6 could have a rationale in the treatment of PPHTN.

Respiratory failure and hypoxemia in the cirrhotic patient including hepatopulmonary syndrome

PURPOSE OF REVIEW

Liver cirrhosis and portal hypertension present with three unique pulmonary complications that are the subject of ongoing clinical research: hepatopulmonary syndrome, portopulmonary hypertension (POPH), and hepatic hydrothorax. The present article is based on a review of the current literature on how to manage these disorders, which are highly important to both anesthesiologists and intensive care physicians.

RECENT FINDINGS

Hepatopulmonary syndrome leads to progressive hypoxemia through diffuse vasodilatation of the pulmonary microcirculation. Liver transplantation, although associated with increased mortality, is the only viable treatment. POPH occurs when vascular remodeling triggers an increase in pulmonary artery pressure and resistance. The role of liver transplantation in POPH is controversial given the excessive mortality in patients with moderate to severe POPH. Medical treatment is able to decrease pulmonary artery pressures, though multicenter randomized controlled trials showing improved outcome are lacking to date. Ultrasound plays an increasingly important role in the diagnosis of all three conditions.

SUMMARY

Patients with end-stage liver disease are at risk for respiratory failure and hypoxemia and need to be screened for hepatopulmonary syndrome, POPH, and hepatic hydrothorax. Failure to timely recognize and adequately treat these complications of cirrhosis may have severe consequences.

The complex interrelationships between chronic lung and liver disease: a review

Lung complications may occur as a result of hepatic disease from any cause and represent a highly heterogeneous group of conditions. Early recognition of such complications may be challenging but is crucial both in forming a meaningful differential diagnosis and in avoiding severe sequelae and irreversible damage. Although a number of different pathogenetic mechanisms are likely to be involved, chronic liver dysfunction may cause pulmonary manifestations because of alterations in the production or clearance of circulating cytokines and other mediators. This is likely to be the case in hepatopulmonary syndrome, portopulmonary hypertension and primary biliary cirrhosis, although their pathogenesis remains largely speculative. Moreover, the severity of lung manifestations may or may not correspond to that of liver impairment, making disease outcome often unpredictable. Congenital and inflammatory disorders, however, may primarily affect both the liver and lung. Apart from specific diseases, a number of medications can also result in pulmonary and hepatic toxic effects. This is particularly important with cytokine therapy - used to treat viral hepatitis, among other diseases - because treatment consists of drug discontinuation, which, in turn, may cause reactivation or progression of the underlying disease that the drug was used for. This review summarizes salient diagnostic and therapeutic aspects of these often misdiagnosed conditions and highlights, based on the most recent literature, the need for early referral of such patients to centres with specific expertise in the field. In fact, a multidisciplinary approach involving pulmonologists, hepatologists and, in particularly severe cases, transplant surgeons has been already proven successful.

Pulmonary complications in liver disease

Pulmonary complications of liver disease are poorly understood and often identified late. Abnormalities of the pulmonary vasculature lead to two distinct complications, hepatopulmonary syndrome and portopulmonary hypertension, which differ in their clinical features and management. This article focuses on these two entities.

Portopulmonary hypertension: short review

Portopulmonary hypertension (PoPH) is an underrecognized complication of portal hypertension, related to cirrhosis and noncirrhotic portal hypertension. PoPH has been found in 5-6% of patients with decompensated liver disease and may adversely affect outcome after liver transplantation. The prevalence of PoPH is unrelated to the severity of liver disease but associated with female sex and underlying autoimmune liver disease. Diagnosis of PoPH is based on screening with Doppler echocardiography and confirmation by right-heart catheterization. Treatment options with proven efficacy in idiopathic pulmonary hypertension include endothelin receptor antagonists, prostanoids, and sildenafil. In PoPH, such targeted treatment was found to be safe in small uncontrolled studies but randomized trials demonstrating its benefit are lacking.

Major adverse events, pretransplant assessment and outcome prediction

Liver cirrhosis and portal hypertension pose enormous loss of lives and resources throughout the world, especially in endemic areas of chronic viral hepatitis. Although the pathophysiology of cirrhosis is not completely understood, the accumulating evidence has paved the way for better control of the complications, including gastroesophageal variceal bleeding, hepatic encephalopathy, ascites, hepatorenal syndrome, hepatopulmonary syndrome and portopulmonary hypertension. Modern pharmacological and interventional therapies have been designed to treat these complications. However, liver transplantation (LT) is the only definite treatment for patients with preterminal end-stage liver disease. To pursue successful LT, the meticulous evaluation of potential recipients and donors is pivotal, especially for living donor transplantation. The critical shortage of cadaveric donor livers is another concern. In many Asian countries, cultural and religious concerns further limit the number of the donors, which lags far behind that of the recipients. The model for end-stage liver disease (MELD) scoring system has recently become the prevailing criterion for organ allocation. Initial results showed clear benefits of moving from the Child-Turcotte-Pugh-based system toward the MELD-based organ allocation system. In addition to the MELD, serum sodium is another important prognostic predictor in patients with advanced cirrhosis. The incorporation of serum sodium into the MELD could enhance the performance of the MELD and could become an indispensable strategy in refining the priority for LT. However, the feasibility of the MELD in combination with sodium in predicting the outcome for patients on transplant waiting list awaits actual outcome data before this becomes standard practice in the Asia-Pacific region.

Diagnosis and assessment of pulmonary arterial hypertension

The diagnosis and assessment of pulmonary arterial hypertension is a rapidly evolving area, with changes occurring in the definition of the disease, screening and diagnostic techniques, and staging and follow-up assessment. The definition of pulmonary hypertension has been simplified, and is now based on currently available evidence. There has been substantial progress in advancing the imaging techniques and biomarkers used to screen patients for the disease and to follow up their response to therapy. The importance of accurate assessment of right ventricular function in following up the clinical course and response to therapy is more fully appreciated. As new therapies are developed for pulmonary arterial hypertension, screening, prompt diagnosis, and accurate assessment of disease severity become increasingly important. A clear definition of pulmonary hypertension and the development of a rational approach to diagnostic assessment and follow-up using both conventional and new tools will be essential to deriving maximal benefit from our expanding therapeutic armamentarium.

Updated clinical classification of pulmonary hypertension

The aim of a clinical classification of pulmonary hypertension (PH) is to group together different manifestations of disease sharing similarities in pathophysiologic mechanisms, clinical presentation, and therapeutic approaches. In 2003, during the 3rd World Symposium on Pulmonary Hypertension, the clinical classification of PH initially adopted in 1998 during the 2nd World Symposium was slightly modified. During the 4th World Symposium held in 2008, it was decided to maintain the general architecture and philosophy of the previous clinical classifications. The modifications adopted during this meeting principally concern Group 1, pulmonary arterial hypertension (PAH). This subgroup includes patients with PAH with a family history or patients with idiopathic PAH with germline mutations (e.g., bone morphogenetic protein receptor-2, activin receptor-like kinase type 1, and endoglin). In the new classification, schistosomiasis and chronic hemolytic anemia appear as separate entities in the subgroup of PAH associated with identified diseases. Finally, it was decided to place pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis in a separate group, distinct from but very close to Group 1 (now called Group 1'). Thus, Group 1 of PAH is now more homogeneous.

Pulmonary complications of cirrhosis

Advanced liver disease and portal hypertension produce various intrathoracic complications that involve the pleural space, the lung parenchyma, and the pulmonary circulation. Dyspnea and arterial hypoxemia are the most common symptoms and signs in patients with such complications. This article focuses on the diagnosis and management of hepatopulmonary syndrome, portopulmonary hypertension, and hepatic hydrothorax. All are pulmonary processes associated with end-stage liver disease that lead to significant morbidity and affect the quality of life of patients who are suffering from liver cirrhosis.

Systolic pulmonary artery pressure and echocardiographic measurements in patients with euthyroid Hashimoto's thyroiditis

BACKGROUND

The aim of this study was to investigate systolic pulmonary artery pressure (SPAP) and echocardiographic findings in patients with euthyroid Hashimoto's thyroiditis (HT).

METHODS

Thirty (8 male, 22 female, mean age 47.4+/-10.5 yr) consecutive patients with euthyroid HT and 30 (9 male, 21 female, mean age 46.4+/-10.7 yr) healthy controls were included in the study. Transthoracic echocardiography was performed for all patients and levels of thyroid hormones, thyroid autoantibodies, glucose, insulin, urea, and creatinine were compared.

RESULTS

There were no significant differences in sex, age, body mass index, serum free T4, serum TSH, lipid profiles between patients and controls. Mean SPAP in patients with euthyroid HT were significantly higher than in controls (31.6+/-5.0 vs 25.6+/-4.5 mmHg, p=0.005). Late diastolic transmitral velocity and isovolumic relaxation time were also significantly higher in patients in comparison to controls. In addition, euthyroid HT patients with tricuspid or mitral regurgitation had a higher grade. Correlation between SPAP and antithyroid antibodies and TSH, however, was not significant in this population.

CONCLUSIONS

Pulmonary arterial pressure is higher in patients with euthyroid HT. There may be a relationship between elevated pulmonary arterial pressure and autoimmune thyroid disease independent from thyroid function status. However, further investigations are needed to determine the exact mechanism of association between autoimmune thyroid diseases and pulmonary hypertension.

Endothelin receptor antagonism in portal hypertension

BACKGROUND

Endothelin receptor antagonists (ERAs) have recently become prominent therapies for pulmonary arterial hypertension, and are being explored clinically in several areas, including resistant hypertension, idiopathic pulmonary fibrosis, and cancer.

OBJECTIVE

To review the available preclinical and clinical data surrounding ERAs and their potential role to treat portal hypertension.

METHODS

A systematic search of peer-reviewed publications was performed using PubMed and Ovid/Medline/EMBASE databases.

RESULTS

Several preclinical in vivo studies have evaluated ERAs in models of portal hypertension. The majority of these studies employ nonselective ERAs, and support the hypothesis that endothelin participates in the development and maintenance of portal hypertension. A limited number of studies have addressed whether ET(A) receptor-selective ERAs provide an advantage over nonselective agents in ameliorating the effects of portal hypertension, and the majority of these data indicate that selective ERAs may be sufficient. Very few clinical studies have evaluated ERAs in portal hypertension patients. What has been described in humans supports a role for endothelin, but is not sufficient to draw conclusions regarding ERA selectivity.

CONCLUSION

While preclinical evidence suggests a role for endothelin and ERAs in portal hypertension, scant and equivocal clinical data highlight a need for human studies with current selective and nonselective ERAs.

Pulmonary hypertension after liver transplantation: case presentation and review of the literature

Hepatopulmonary syndrome and portopulmonary hypertension are the most common pulmonary vascular complications in patients with cirrhosis. Usually but not universally mutually exclusive, they each may present prior to liver transplantation and, if severe enough, may be a contraindication to transplant. However, there have been a number of case reports describing patients developing pulmonary hypertension de novo after liver transplantation. This report describes one such patient from our institution and reviews the medical literature describing this unusual clinical entity.