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

Portopulmonary hypertension: survival and prognostic factors

RATIONALE

Portopulmonary hypertension (PoPH) can be defined as elevation of pulmonary arterial pressure and pulmonary vascular resistance in the setting of portal hypertension. Survival results in PoPH are contrasting, and prognostic factors need to be identified.

OBJECTIVES

To analyze long-term survival in a large cohort of patients with PoPH with the aim of determining the independent variables affecting survival.

METHODS

We retrospectively analyzed charts of all patients referred to the French Referral Center for pulmonary arterial hypertension with the diagnosis of PoPH between 1984 and 2004.

MEASUREMENTS AND MAIN RESULTS

The study population comprised 154 patients; 57% male. Mean age at diagnosis was 49 +/- 11 years, 60% of patients were in New York Heart Association functional class III-IV, and mean 6-minute walk distance was 326 +/- 116 m. Hemodynamic measurements showed a mean pulmonary arterial pressure of 53 +/- 13 mm Hg, cardiac index of 2.9 +/- 0.9 L/min/m(2), and pulmonary vascular resistance of 752 +/- 377 dyn/s/cm(5). Portal hypertension was related to cirrhosis in 136 patients, with a severity assessed as follows: Child-Pugh class A 51%, Child-Pugh class B 38%, Child-Pugh class C 11%. Overall survival rates at 1, 3, and 5 yr were 88, 75, and 68%, respectively. Multivariate regression analysis individualized the presence and severity of cirrhosis and cardiac index as major independent prognostic factors.

CONCLUSIONS

Prognosis in PoPH is mainly related to the presence and severity of cirrhosis and to cardiac function. The place of pulmonary arterial hypertension-specific therapies remains to be determined in the setting of PoPH.

Evaluation and management of end-stage liver disease in children

End-stage liver disease in children presents a challenging array of medical and psychosocial problems for the health care delivery team. Many of these problems are similar to those encountered by caregivers of adults with end-stage liver disease, such as the development of complications of cirrhosis, including ascites, spontaneous bacterial peritonitis, and esophageal variceal hemorrhage. However, the natural history of disease progression in children and their responses to medical therapy can differ significantly from that of their adult counterparts. Children with end-stage liver disease are especially vulnerable to nutritional compromise; if not effectively managed, this can seriously impact long-term outcomes and survival both before and after liver transplantation. Moreover, close attention must be given to vaccination status and the clinical setting at which health care is delivered to optimize outcomes and the delivery of high-quality pediatric health care. In this review, we address important components of the evaluation and management of children with chronic end-stage liver disease.

Accuracy of Doppler-estimated pulmonary vascular resistance in patients before liver transplantation

The hyperdynamic circulation associated with cirrhosis is typically characterized by high cardiac output and low systemic and pulmonary vascular resistance (PVR). Approximately 4% of cirrhotic patients develop portopulmonary hypertension, which is an important predictor of hemodynamic instability after orthotopic liver transplantation. Doppler estimation of pulmonary artery systolic pressure (PASP) is used as a screening test for the presence of portopulmonary hypertension. We tested the accuracy of a noninvasive measurement of PVR (ratio of peak tricuspid regurgitant velocity [TRV] to right ventricular outflow tract velocity time integral [VTI RVOT]) to detect increased PVR in a population before liver transplantation. We compared test characteristics of the TRV/VTI RVOT ratio to echocardiographically derived PASP for detection of invasively measured PVR >1.5 Wood units. There was no significant correlation between Doppler-derived PASP and invasively measured PVR. There was a moderate and significant correlation between TRV/VTI RVOT ratio and invasively measured PVR. Compared with Doppler-derived PASP, the TRV/VTI RVOT ratio was a more accurate test for PVR >1.5 Wood units. Using a cut-off value of TRV/VTI RVOT >0.12, the sensitivity and negative predictive value for PVR >1.5 Wood units were 100%. In conclusion, the TRV/VTI RVOT ratio is a more accurate screening test for the presence of portopulmonary hypertension than PASP in patients undergoing orthotopic liver transplantation. Routine use of this ratio may decrease the need for invasive hemodynamic assessment in this patient population.

Pulmonary Vascular Disease

The pulmonary vasculature is an anatomic compartment that is frequently overlooked in the histologic review of lung biopsy samples, other than those obtained specifically to assess pulmonary vascular disease.1 Though often of a nonspecific nature, the histologic pattern of vascular remodeling may at times suggest its underlying pathogenesis and provide clues to the cause of pulmonary hypertension.2 Disproportionately severe vascular pathology may further indicate alternate disease processes, such as congestive heart failure or thromboemboli, contributing to the patient’s overall respiratory condition.

Decompensated porto-pulmonary hypertension in a cirrhotic patient with thrombosis of portocaval shunt

We report a case of decompensated porto-pulmonary hypertension closely associated with the development of intra-portocaval shunt thrombosis. A woman with Laennec's cirrhosis was hospitalized because of severe dyspnea and edema. She underwent surgical portocaval anastomosis ten years ago. Imaging studies showed massive intra-shunt thrombosis, portal hypertension, ascites, pleuro-pericardial effusions and enlargement of right cardiac cavities. Cardiac catheterization allowed to rule out coronary and left-sided heart abnormalities and led to the diagnosis of pre-capillary pulmonary hypertension. Antithrombotic treatment with low molecular weight heparin was instituted. The management also included ACE inhibitors, spironolactone, low-salt diet and lactulose. The patient was discharged and three months later we observed the disappearance of edema, ascites and pleuro-pericardial effusions, a marked body weight reduction and improved dyspnea and liver function tests. A possible link between the development of intra-shunt thrombosis and clinical decompensation in our patient was hypothesized. In fact, it has been demonstrated that the increased portal pressure, caused by occlusion of portosystemic shunt, reduces renal plasma flow and increases systemic endothelin-1 concentration. In our patient the disappearance of edematous state and improved dyspnea observed after recanalization of the shunt strongly support this hypothesis.

Pre- and postoperative systemic hemodynamic evaluation in patients subjected to esophagogastric devascularization plus splenectomy and distal splenorenal shunt: A comparative study in schistomomal portal hypertension

AIM: To investigate the systemic hemodynamic effects of two surgical procedures largely employed for treatment of schistosomal portal hypertension.

METHODS: Thirty-six patients undergoing elective surgical treatment of portal hypertension due to hepatosplenic mansonic schistosomiasis were prospectively evaluated. All patients were subjected to preoperative pulmonary artery catheterization; 17 were submitted to esophagogastric devascularization and splenectomy (EGDS) and 19 to distal splenorenal shunt (DSRS). The systemic hemodynamic assessment was repeated 4 d after the surgical procedure.

RESULTS: Preoperative evaluation revealed (mean ± SD) an increased cardiac index (4.78 ± 1.13 L/min per m²), associated with a reduction in systemic vascular resistance index (1457 ± 380.7 dynes.s/cm⁵.m²). The mean pulmonary artery pressure (18 ± 5.1 mmHg) as well as the right atrial pressure (7.9 ± 2.5 mmHg) were increased, while the pulmonary vascular resistance index (133 ± 62 dynes.s/cm⁵.m²) was decreased. Four days after EGDS, a significant reduction in cardiac index (3.80 ± 0.4 L/min per m², P < 0.001) and increase in systemic vascular resistance index (1901.4 ± 330.2 dynes.s/cm⁵.m², P < 0.001) toward normal levels were observed. There was also a significant reduction in pulmonary artery pressure (12.65 ± 4.7 mmHg, P < 0.001) and no significant changes in the pulmonary vascular resistance index (141.6 ± 102.9 dynes.s/cm⁵.m²). Four days after DSRS, a non-significant increase in cardiac index (5.2 ± 0.76 L/min per m²) and systemic vascular resistance index (1389 ± 311 dynes.s/cm⁵.m²) was observed. There was also a non-significant increase in pulmonary artery pressure (19.84 ± 5.2 mmHg), right cardiac work index (1.38 ± 0.4 kg.m/m²) and right ventricular systolic work index (16.3 ± 6.3 g.m/m²), without significant changes in the pulmonary vascular resistance index (139.7 ± 67.8 dynes.s/cm⁵.m²).

CONCLUSION: The hyperdynamic circulatory state observed in mansonic schistosomiasis was corrected by EGDS, but was maintained in patients who underwent DSRS. Similarly, the elevated mean pulmonary artery pressure was corrected after EGDS and maintained after DSRS. EGDS seems to be the most physiologic surgery for patients with schistosomal portal hypertension.

Pulmonary arterial hypertension: an overview

Pulmonary arterial hypertension (PAH) was first described over 100 years ago, but a thorough understanding of its patho-genesis and a successful approach to curing the disease remain elusive. Increased research activity has greatly enhanced our understanding of the disease and led to new therapies that retard disease progression and improve patient function and survival. The disease is rare, but effects people of all ages and is associated with several seemingly unconnected diseases. It is not clear whether all forms of PAH represent the same disease or the same pathologic endpoint of different pulmonary vascular disease processes. Recent attempts to classify different forms of pulmonary hyper-tension by the diseases with which they are associated has helped researchers organize data collected from patient registries and clinical trials. This overview discusses the history, epidemiology, and genetic basis of PAH, new recommendations for disease classification, and prognostic variables shown to adversely affect survival.

Portopulmonary hypertension

As a result of the success of orthotopic liver transplantation, there has been increasing interest in the diagnosis and therapeutic options for the pulmonary vascular complications of hepatic disease. These pulmonary vascular complications range from the hepatopulmonary syndrome, which is characterized by intrapulmonary vascular dilatations, to portopulmonary hypertension (POPH), which is characterized by an elevated pulmonary vascular resistance as a consequence of obstruction to pulmonary arterial blood flow. This review concentrates on POPH.

Diagnosis of pulmonary arterial hypertension

Accurate diagnosis of pulmonary arterial hypertension is a challenging and complex process that requires a high index of clinical suspicion from even the most astute clinician. This article discusses the use of a variety of noninvasive tests that can help define the population of patients in whom invasive cardiac catheterization should be pursued. It points out the vagaries and limitations of electrocardiography and the radiographic and echocardiographic clues to the diagnosis. Ultimately, right- and, often, concomitant left-heart catheterization is required to establish the diagnosis and distinguish pulmonary arterial hypertension from pulmonary venous hypertension.

Pulmonary vascular abnormalities in cirrhosis

Two pulmonary vascular disorders can occur in liver disease and/or portal hypertension: the hepatopulmonary syndrome (HPS), which is characterized by intrapulmonary vascular dilatations, and portopulmonary hypertension (POPH), in which pulmonary vascular resistance is elevated. POPH and HPS are characterized by distinct pulmonary microvascular remodelling, which occurs at different anatomical sites of the pulmonary microcirculation. The exact pathophysiological mechanisms of these pulmonary vascular disorders are unknown. However, as HPS and POPH have been reported in patients with extrahepatic portal hypertension, the factor that determines their development must be portal hypertension. The clinical presentations are very different, with gas exchange impairment in HPS and hemodynamic failure in POPH. The severity of HPS seems to parallel the severity of liver failure, whereas no simple relationship has been identified between hepatic impairment and the severity of POPH. Resolution of HPS is common after liver transplantation, which has an uncertain effect in POPH.

Portopulmonary hypertension: Results from a 10-year screening algorithm

Portopulmonary hypertension (POPH) is the elevation of pulmonary artery pressure due to increased resistance to pulmonary blood flow in the setting of portal hypertension. Increased mortality has occurred with attempted liver transplantation in such patients and thus, screening for POPH is advised. We examined the relationship between screening echocardiography and right heart catheterization determinations of pressure, flow, volume, and resistance. A prospective, echocardiography-catheterization algorithm was followed from 1996 to 2005. Consecutive transplantation candidates underwent Doppler echocardiography to determine right ventricular systolic pressure (RVSP). Of 1,235 patients, 101 with RVSP >50 mm Hg underwent catheterization to measure mean pulmonary artery pressure (MPAP), flow via cardiac output (CO), central volume via pulmonary artery occlusion pressure (PAOP), and resistance via calculated pulmonary vascular resistance (PVR). Bland-Altman analysis suggested marked discordance between echocardiography-derived RVSP and catheterization results. All-cause pulmonary hypertension (MPAP >25 mm Hg) was documented in 90/101 (90%) patients. Using current pressure and resistance diagnostic guidelines (MPAP >25 mm Hg, PVR > or =240 dynes/s/cm(-5)), POPH was documented in 66/101 (65%) patients. Elevated MPAP was due to increased CO and/or PAOP in 35/101 (35%) patients with normal resistance (PVR <240 dynes/s/cm(-5)). The transpulmonary gradient (MPAP-PAOP) further characterized POPH in the presence of increased volume. Model for end stage liver disease (MELD) scores correlated poorly with MPAP and PVR. In conclusion, right heart catheterization is necessary to confirm POPH and frequently identifies other reasons for pulmonary hypertension (e.g., high flow and increased central volume) in liver transplantation candidates. Severity of POPH correlates poorly with MELD scores.

Hypertension portopulmonaire

INTRODUCTION

Porto-pulmonary hypertension (PoPH) is the association of pulmonary artery hypertension and portal hypertension. The diagnosis of PoPH is based on pulmonary haemodynamic criteria, obtained via right heart catheterisation, including an increase in mean pulmonary arterial pressure (> 25 mmHg) and in pulmonary vascular resistance (> 240 dyn.s.cm-5).

STATE OF THE ART

The exact pathophysiological mechanisms of PoPH are unknown. However, since PoPH has been reported in patients with non-hepatic portal hypertension, the factor that determines the development must be portal hypertension rather than liver disease per se. Moreover, no simple relationship has been identified between the degree of hepatic impairment and the severity of PoPH. The clinical presentation is non-specific with haemodynamic failure occurring at the end stage. As a consequence, screening by annual transthoracic echocardiography is highly recommended in potential liver transplant candidates. Therapy with prostacyclin analogues may partially relieve pulmonary arterial hypertension (PAH). Liver transplantation has an uncertain effect in PoPH and because PoPH is associated with a high perioperative mortality, moderate to severe PoPH remains a contraindication for liver transplantation.

PERSPECTIVES AND CONCLUSIONS

Recent advances in the management of PoPH have improved the prognosis. The safety and efficacy of oral endothelin receptor antagonists and oral phosphodiesterase inhibitors is currently under evaluation. A therapeutic approach utilising combinations of drugs should provide better long-term results.

The role of trans-oesophageal echocardiography for perioperative cardiovascular monitoring during orthotopic liver transplantation

Patients undergoing orthotopic liver transplantation frequently display considerable physiological changes during the procedure as a result of both the disease process and the surgery. Anaesthesia is often challenging and relies upon advanced monitoring techniques to provide data pertinent to peri-operative management. Traditionally the pulmonary artery flotation catheter has been regarded as the gold standard for cardiac output and right heart monitoring. This review examines whether trans-oesophageal echocardiography merits a place in the continuing evolution of this technically advanced and challenging anaesthetic field.

Portopulmonary Hypertension in the Early Phase Following Liver Transplantation

BACKGROUND

Portopulmonary hypertension (PPH) is a severe complication of liver cirrhosis, which poses a high risk for postliver transplantation (LT) mortality. In most liver transplant centers, severe PPH is viewed as an absolute contraindication for LT, but recent reports challenge this. The purpose of our study was to determine the incidence of PPH, its influence on the 30-day mortality rate following LT and to determine the sensitivity and specificity of Doppler echocardiography and electrocardiography as noninvasive tools to determine PPH.

METHODS

We studied 74 consecutive patients that underwent LT between February 2004 and November 2005. Pulmonary arterial pressure and cardiac index were repeatedly determined during surgery and postoperatively. PPH was defined as mild (mean pulmonary arterial pressure (MPAP) 25-35 mm Hg), moderate (MPAP of 35-45 mm Hg) and as severe (MPAP >45 mm Hg).

RESULTS

The total incidence of PPH was 31% (16 mild, 5 moderate, and 2 severe). There was a tendency towards increased 30-day mortality rate in patients with PPH compared to controls (22% vs. 12%, P=0.1). However, the two patients with the most severe PPH survived. The duration of ventilation and total stay at the intensive care unit did not differ significantly between groups. The positive predictive value of Doppler echocardiography for PPH was 39% and the negative predictive value 90%.

CONCLUSIONS

Mild pulmonary hypertension is common in patients with liver failure, whereas moderate and severe hypertension is not. Severe PPH should not be considered as absolute contraindication for LT.

Efficiency and safety of bosentan in child C cirrhosis with portopulmonary hypertension and renal insufficiency

Bosentan has lately been described as a successful therapeutic agent for portopulmonary hypertension consecutive to child A cirrhosis. This is the first report of the effect of this substance with advanced liver cirrhosis (child C) and renal insufficiency. Low doses of bosentan (initially twice 31.25 mg/day and then 62.5 mg/day) increased cardiac output and allowed correction of renal insufficiency; it allowed one to stop the requirement of oxygen and not only improved the 6-min walking test by more than 400 m, but also decreased the severity of the liver cirrhosis to child B stadium. This suggests that patients, who would be excluded from a liver transplantation program because of their portopulmonary hypertension, could profit from a careful therapy with bosentan.

Successful treatment of portopulmonary hypertension with bosentan: case report

Pulmonary arterial hypertension (PAH) is found in 2-20% of cirrhosis patients who have portal hypertension (portopulmonary hypertension, PPHT). Endothelin (ET), a potent vasoconstrictor, is likely to play a role in the pathogenesis of portal hypertension. We describe the long-term successful use of the dual ET(A)/ET(B) receptor antagonist bosentan in a 43-year-old male with alcohol-related cirrhosis (Child-Pugh A), right ventricular enlargement and dysfunction, respectively, and moderate PAH. Elevated pulmonary arterial pressure was substantially reduced and exercise capacity increased. Improvement was maintained over 2 years, and bosentan treatment continues in this patient. Our report is in line with a series of current reports in PPHT that support the use of bosentan in this subset of PAH patients.

Portopulmonary hypertension

Portopulmonary hypertension (PPHT) is defined as precapillary pulmonary hypertension accompanied by hepatic disease or portal hypertension. Pulmonary hypertension results from excessive pulmonary vascular remodeling and vasoconstriction. These histological alterations have been indistinguishable from those of other forms of pulmonary arterial hypertension. Factors involved in the pathogenesis of PPHT include volume overload, hyperdynamic circulation, and circulating vasoactive mediators. The disorder has a substantial impact on survival and requires focused treatment. Liver transplantation in patients with moderate to severe PPHT is associated with a significantly reduced survival rate. The best medical treatment for patients with PPHT is controversial; most authors currently regard continuous intravenous application of prostacyclin as the treatment of choice for patients with severe PPHT. There is only very limited reported experience with inhaled prostacyclin or its analog, iloprost. Increasing evidence of the efficacy of the endothelin-receptor antagonist bosentan and of the phosphodiesterase-5 inhibitor sildenafil is emerging in highly selected patients with PPHT. In the future, a combination therapy of the above-mentioned agents might become a therapeutic option. Other agents such as beta-blockers seem to be harmful to patients with moderate to severe portopulmonary hypertension. Up-to-date, randomized, double-blind, controlled clinical trials are lacking and are needed urgently.

Bosentan treatment of portopulmonary hypertension related to liver cirrhosis owing to hepatitis C

Pulmonary arterial hypertension (PAH) with coexisting portal hypertension has been defined as portopulmonary hypertension (PPHTN). It is often related to liver cirrhosis of various aetiologies and is associated with a high mortality rate. Endothelin-1 (ET) is supposed to play an important role in the pathogenesis of PAH as well as portal hypertension. Therefore, therapy with an ET(A)/ET(B) receptor antagonist might be of use in the treatment of PPHTN. We report the case of a 76-year-old male with liver cirrhosis owing to chronic hepatitis C virus infection and PPHTN who was treated with the dual ET(A)/ET(B) receptor antagonist bosentan. The patient showed remarkable improvement of 6-min walking distance from 300 to 480 m after 2 weeks and to 540 m after 14 weeks, respectively. In addition, a significant decline of N-terminal pro B-type natriuretic peptide fraction (NT-proBNP) from 4928 ng mL(-1) to 640 ng mL(-1) was observed. Bosentan might be a promising new therapeutical option for patients suffering from PPHTN.

Endothelin and endothelin receptor antagonism in portopulmonary hypertension

Portopulmonary hypertension (PPHT) is a rare but devastating complication in patients with portal hypertension, characterized by pulmonary arterial obliterative disease with a concomitant rise in pulmonary vascular resistance. A broad body of evidence has accumulated, indicating that endothelin (ET) peptides and their cognate receptors are causally involved in the pathophysiology of pulmonary arterial hypertension (PAH) owing to different aetiologies, including PPHT. In addition, the ET system may be involved in hepatic fibrotic remodelling and portal hypertension. Several experimental models have provided evidence that ET receptor antagonism may have therapeutic potential in PPHT. Initial experience has accumulated during the last 2 years, suggesting that targeting the ET system may have beneficial effects in the clinical setting. In these studies, the orally active, dual ET receptor antagonist bosentan improved pulmonary haemodynamics and functional capacity. These effects were sustained and occurred in the absence of adverse events. If these observations can be corroborated by controlled clinical trials, bosentan would offer several advantages over available therapies, which have major drawbacks owing to their invasive and demanding mode of application.

Portopulmonary hypertension

Portopulmonary hypertension is a common condition in patients who have portal hypertension. This article reviews the definition and clinical presentation of this disorder and outlines our current understanding of its pathophysiology. A diagnostic approach is provided , and novel medical therapies that are being investigated to treat this condition are discussed. Finally, the safety of liver transplantation in patients who have portopulmonary hypertension is reviewed.

Sildenafil decreased pulmonary arterial pressure but may have exacerbated portal hypertension in a patient with cirrhosis and portopulmonary hypertension

Portopulmonary hypertension is a recognized but uncommon complication of cirrhosis. Liver transplantation may be contraindicated in patients with severe portopulmonary hypertension. In order to decrease the pulmonary arterial pressure, intravenous administration of epoprostenol has been shown to provide substantial beneficial results in these patients. Additionally, a recent case report demonstrated that long-term oral administration of sildenafil decreased pulmonary arterial pressure, but its effects on splanchnic hemodynamics were not measured. We report on a patient with cirrhosis and portopulmonary hypertension and the changes in the hemodynamic status after an oral administration of sildenafil. This case report clearly delineates that sildenafil decreases pulmonary arterial pressure but may exacerbate portal hypertension and hyperdynamic circulation in patients with cirrhosis and portopulmonary hypertension.

Development of pulmonary hypertension in 5 patients after pediatric living-donor liver transplantation: de novo or secondary?

The development of portopulmonary hypertension (PH) in a patient with end-stage liver disease is related to high cardiac output and hyperdynamic circulation. However, PH following liver transplantation is not fully understood. Of 617 pediatric patients receiving transplants between June 1990 and March 2004, 5 (median age 12 yr, median weight 24.5 kg) were revealed to have portopulmonary hypertension (PH) after living-donor liver transplantation (LDLT), as confirmed by echocardiography and/or right heart catheterization. All children underwent LDLT for post-Kasai biliary atresia. In 2 patients with refractory biliary complications, PH developed following portal thrombosis; 2 with stable graft function, who had had intrapulmonary shunting (IPS) before LDLT, were found to have PH in spite of overcoming liver dysfunction due to hepatitis. PH developed shortly after distal splenorenal shunting in 1 patient, who suffered liver cirrhosis due to an intractable outflow blockage. The onset of PH ranged from 2.8 to 11 yr after LDLT, and mean pulmonary artery pressure (mPAP) estimated by echocardiography at the time of presentation ranged from 43 to 120 mmHg. Three of the 5 patients are alive under prostaglandin I2 (PGI2) treatment. Of these, 1 is prepared for retransplantation for an intractable complications of liver allograft, while the other 2 with satisfactory grafts are being considered for lung transplantation. Even after LDLT, PH can develop with portal hypertension. Periodic echocardiography is essential for early detection and treatment of PH especially in the recipients with portal hypertension not only preoperatively but also postoperatively.

Portopulmonary hypertension: hemodynamics, pulmonary angiography, and configuration of the heart

BACKGROUND

The goal of the present study was to examine the cardiac configuration and pulmonary vascular changes in patients with portopulmonary hypertension (PPHTN) and compare them with those of idiopathic pulmonary arterial hypertension (IPAH).

METHODS AND RESULTS

The subjects were 10 patients with PPHTN and 18 with IPAH. In PPHTN, the increases in the right ventricular end-diastolic volume index (89+/-19 vs 128+/-50 ml/m2; p=0.04), right end-systolic volume index (50+/-19 vs 95+/-47 ml/m 2; p=0.02) and right ventricular mass index (47+/-18 g/m2 vs 79+/-31; p=0.04) were low compared with IPAH. The decrease in the right ventricular ejection fraction was also low in PPHTN (45+/-10 vs 28+/-13%; p=0.01). The degree of sparse arborization and abrupt narrowing on wedged pulmonary angiography was moderate in PPHTN compared with IPAH. In PPHTN, the proximal pulmonary arteries were dilated near the segmental arteries, which were narrow in IPAH.

CONCLUSION

Changes in the configuration of the heart were moderate in PPHTN compared with those in IPAH. The degree of sparse arborization and abrupt narrowing were also moderate in PPHTN.

The pulmonary involvement in portal hypertension: portopulmonary hypertension and hepatopulmonary syndrome

Pulmonary abnormalities are common in patients with advanced chronic liver disease. Two distinct syndromes strictly related to the presence of portal hypertension, but clearly different from a pathophysiologic point of view, have been identified. Portopulmonary hypertension, characterized by an increased pulmonary arterial pressure, is due to a progressive arteriolar vasoconstriction induced by excess local production of vasoconstrictor substances. Hepatopulmonary syndrome results from intrapulmonary microvascular dilation caused by an inadequate synthesis or metabolism of putative pulmonary vasoactive substances leading to a functional vasodilation of the pulmonary vasculature, ultimately leading to hypoxemia. Controversies on pathogenesis imply different tentative therapeutic approaches for the medical management of these conditions. The development of portopulmonary hypertension or the hepatopulmonary syndrome has important clinical and prognostic implications facing the impact of new therapeutic strategies for the management of the main complications of advanced liver diseases on cardiopulmonary function.

Cardiopulmonary complications in chronic liver disease

Patients with cirrhosis and portal hypertension exhibit characteristic cardiovascular and pulmonary hemodynamic changes. A vasodilatatory state and a hyperdynamic circulation affecting the cardiac and pulmonary functions dominate the circulation. The recently defined cirrhotic cardiomyopathy may affect systolic and diastolic functions, and imply electromechanical abnormalities. In addition, the baroreceptor function and regulation of the circulatory homoeostasis is impaired. Pulmonary dysfunction involves diffusing abnormalities with the development of the hepatopulmonary syndrome and portopulmonary hypertension in some patients. Recent research has focused on the assertion that the hemodynamic and neurohumoral dysregulation are of major importance for the development of the cardiovascular and pulmonary complications in cirrhosis. This aspect is important to take into account in the management of these patients.

Hepatitis C virus and the lung: implications for therapy

Hepatitis C virus (HCV) infection is a chronic blood-borne disease that affects > 4,000,000 individuals in the United States. The majority of individuals with HVC infection acquire a chronic hepatitis that predisposes them to the complications of cirrhosis and hepatoma. Chronic HCV infection is, however, associated with multiple extrahepatic manifestations as well, including recently recognized effects on the lung. These include primary effects on lung function, as well as secondary effects in the settings of progressive liver disease and drug treatment for HCV. In this article, we discuss the emerging clinical data that support a role for HCV infection in lung disease, describe the multiple pulmonary manifestations of this viral infection, and outline the therapies available for specific pulmonary complications of chronic HCV infection.

Diagnostic et classification des hypertensions artérielles pulmonaires

The clinical classification of types of pulmonary hypertension has made it possible to better standardize the approach to the diagnosis and treatment of patients, to perform clinical studies among homogeneous patients, and to discover common laboratory abnormalities that may serve as markers or help elucidate mechanisms of disease. Pulmonary arterial hypertension groups together different diseases that affect the small-caliber pulmonary arteries and lead to a progressive increase in pulmonary arterial resistance and right heart failure. A specific diagnosis of pulmonary arterial hypertension is generally based on a detailed and methodical clinical evaluation. Pulmonary biopsy is rarely indicated. Work-up in a center specialized in the management of this disease is frequently appropriate when the cause of the hypertension is not clear or when a specific treatment is envisaged.

Hemodynamics and survival of patients with portopulmonary hypertension

It is not known whether patients with pulmonary arterial hypertension associated with portal hypertension (portopulmonary hypertension (PPHTN) have different disease characteristics from those of patients with other forms of pulmonary arterial hypertension. We performed a retrospective cohort study of patients with PPHTN and patients with pulmonary arterial hypertension that was idiopathic, familial, or associated with anorexigen use (IPAH) to determine whether hemodynamics or survival were different between these groups. We included consecutive patients who underwent initial pulmonary artery catheterization and vasodilator testing at our center between January 1997 and May 2001 and who were followed until January 2004. Patients with PPHTN (N = 13) had a higher cardiac index and lower pulmonary vascular resistance than patients with IPAH (N = 33) (P < or = 0.001). Right atrial pressure and pulmonary artery pressure were similar between the groups. Patients with PPHTN had a higher risk of death in multivariate analysis (hazard ratio: [HR] = 2.8, 95% CI 1.04-7.4; P = 0.04). These findings were not affected by adjustment for differences in laboratory values, hemodynamics, or therapy. In conclusion, patients with PPHTN have a higher risk of death than that of patients with IPAH, despite having a higher cardiac index and lower pulmonary vascular resistance. Future studies of the specific mechanisms of and therapy for pulmonary arterial hypertension should focus on the distinctions between the different forms of this disease.

Classificação e avaliação diagnóstica da hipertensão pulmonar

Nos últimos anos, observou-se um grande avanço no conhecimento da fisiopatologia da hipertensão pulmonar, o que permitiu a identificação tanto de fatores de risco bem definidos, quanto de condições clínicas que levam ao seu desenvolvimento. Isso possibilitou ainda uma melhor classificação dos quadros de hipertensão pulmonar, baseada na investigação sistematizada desses quadros, permitindo, em última análise, o correto manuseio terapêutico. Atualmente, busca-se cada vez mais identificar as situações em que o diagnóstico precoce se torna possível, a fim de se instituir medidas terapêuticas em uma fase mais inicial da doença, evitando-se assim sua progressão.

Portopulmonary hypertension in pediatric patients

OBJECTIVES

To investigate the clinical presentation, manifestations, and response to therapy of portopulmonary hypertension (PPHTN) in pediatric patients.

STUDY DESIGN

This study was a retrospective chart review describing the evaluation and course of 7 patients with PPHTN.

RESULTS

Causes of portal hypertension (HTN) included biliary atresia (3 cases), cavernous transformation of the portal vein (2 cases), and primary sclerosing cholangitis and cryptogenic cirrhosis (1 case each). The median interval from the diagnosis of portal HTN to PPHTN was 12.1 years. Four patients presented with a new heart murmur, 4 presented with syncope, and 3 presented with dyspnea. Although electrocardiograms (ECGs) and chest x-rays were normal in 3 and 2 patients, respectively, echocardiograms diagnosed pulmonary HTN in all 7 patients. Five patients had cardiac catheterizations; the average mean pulmonary artery pressure was 65 +/- 20 mm Hg. Response to therapy was variable, and 4 patients died. Postmortem lung tissue examination revealed plexiform lesions and pulmonary arteriopathy.

CONCLUSIONS

Because symptoms are subtle and may be overlooked, pediatric patients with portal HTN who develop a new heart murmur, dyspnea, syncope, or who are being evaluated for liver transplantation require evaluation for PPHTN. ECG and chest x-ray are insensitive screens for PPHTN. An echocardiogram and cardiology evaluation is essential for the diagnosis.

An overview of pulmonary arterial hypertension: risks, pathogenesis, clinical manifestations, and management

This article focuses on pulmonary arterial hypertension, including both primary pulmonary hypertension (PPH) and those forms of pulmonary arterial hypertension that are related to other factors, including collagen vascular diseases, congenital shunts, portal hypertension, human immunodeficiency viral infection, and exposure to specific drugs and toxins. Risks for different types of pulmonary arterial hypertension are identified. The common pathogenesis for pulmonary arterial hypertension is discussed, and includes an overview of the role of key vasoactive substances such as nitric oxide, prostacyclin, endothelin, and thromboxane. Typical presenting clinical manifestations, recommendations for screening of patients at risk, and key diagnostic findings are discussed. The mainstay of treatment is identified as pharmacologic, and may include diuretics, digoxin, warfarin, calcium channel antagonists, and prostacyclin analogues such as epoprostenol. Surgical interventions are considered as a last resort, and may include unilateral or bilateral lung transplant or atrial septostomy. Treatment options for patients with pulmonary arterial hypertension hold more hope today than they did a decade ago and are identified so as to guide the advanced practice nurse in recognizing and then facilitating the appropriate management of patients with this rare but disabling disease.

Development of hypoxemia in alcoholic liver disease

The aim of this study was to investigate the arterial hypoxemia in Japanese patients with alcoholic liver disease (ALD) with regard to alcohol consumption and/or disease severity. Hypoxemia was observed in 78% patients with ALD and in all 46 patients with alcoholic liver cirrhosis (ALC) and 33 (56%) of 59 patients with noncirrhotic alcoholic liver disease (NCALD) (P < 0.0001). The partial pressure of oxygen (PaO2) was 71.1 +/- 5.2 mm Hg in ALC and 78.7 +/- 6.3 mm Hg in NCALD (P < 0.0001). The oxygen consumption in ALD was significantly higher than that in control subjects (P < 0.0001), and a high oxygen consumption was seen in 88% of the patients with ALD, in all 46 ALC patients, and in 46 (78%) of 59 NCALD patients (P < 0.01). Following abstinence from alcohol, the PaO2 and oxygen consumption significantly recovered after day 2 (P < 0.0001), whereas the prothrombin index did not change in either NCALD or ALC patients. Multivariate analysis showed that alcohol consumption and oxygen consumption were significant independent predictors of PaO2. In conclusion, the present findings suggest that increased oxygen consumption due to alcohol ingestion is principally responsible for the hypoxemia in ALD patients.

Development of hepatopulmonary syndrome and portopulmonary hypertension in a paediatric liver transplant patient

BACKGROUND

Hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPH) are pulmonary vascular disorders which occur in patients with severe liver disease and/or portal hypertension. Although these syndromes are frequently diagnosed in patients undergoing assessment for liver transplantation, they seldom occur in the same patient.

METHOD

This report describes a female paediatric patient, born with extra-hepatic biliary atresia, who required liver transplantation, at the age of 15, for secondary biliary cirrhosis. She had severe HPS prior to her first liver transplant, which resolved rapidly following surgery, as well as indirect evidence for PPH. She required a second liver transplant 1 yr later for chronic rejection. Whilst evaluating the patient for a third liver transplant, 4 yr later, severe PPH was discovered. The patient died 3 months later from right heart failure.

CONCLUSION

HPS and PPH may coexist however they may show differing responses to liver transplantation with progression of PPH despite the resolution of HPS.

Screening, early detection, and diagnosis of pulmonary arterial hypertension: ACCP evidence-based clinical practice guidelines

Pulmonary arterial hypertension (PAH) occurs as an idiopathic process or as a component of a variety of disease processes, including chronic thromboembolic disease, connective tissue diseases, congenital heart disease, and exposure to exogenous factors including appetite suppressants or infectious agents such as HIV. This article reviews evidence for screening in susceptible patient groups and the approach to diagnosing PAH when it is suspected, and provides specific recommendations for applying this evidence to clinical practice.

Classification and epidemiology of pulmonary hypertension

Pulmonary hypertension is a complex disease that can be idiopathic, familial, or associated with a wide range of disease processes. This article outlines the classification of primary pulmonary hypertension and discusses the various types of the disease.

The biological "scrabble" of pulmonary arteriovenous malformations: considerations in the setting of cavopulmonary surgery

Pulmonary arteriovenous fistulas are vascular malformations, which, by virtue of producing abnormal vascular connections proximal to the units of gas exchange, result in intrapulmonary right-to-left shunting. These malformations or fistulas reflect at least in part disordered angiogenesis, and less commonly recruitment and dilation of pre-existing vascular channels. Pulmonary arteriovenous fistulas occur in a number of diverse clinical settings. Such fistulas are a well-established feature of the Weber-Osler-Rendu complex, or hereditary haemorrhagic telangiectasia, an autosomal dominant vascular dysplasia characterized by mucocutaneous telangiectasis, epistaxis, gastrointestinal haemorrhage, and arteriovenous malformations in the lung, brain, liver and elsewhere. They are also seen in the patient with acute or chronic liver disease, disease that is usually but not invariably severe, or those with non-cirrhotic portal hypertension. They may occur as congenital malformations, single or diffuse, large or small in isolation, and when large or extensive enough may result in hypoxaemia, clinical cyanosis, and heart failure. Cerebral vascular accidents are also a well-known complication of this disorder. An extensive literature has accumulated with regard to the pulmonary arteriovenous fistulas seen in the setting of the Weber-Osler-Rendu complex, and there is considerable information on the genetics, basic biology, clinical findings, complications and therapeutic interventions of these malformations in the setting of this syndrome. These issues, however, are not the primary considerations of this review, although some aspects of this fascinating disorder will be discussed later. Rather the focus will be on pulmonary arteriovenous malformations that develop in the setting of cavopulmonary surgery, and their relationship to the pulmonary arteriovenous fistulas occurring in the hepatopulmonary syndrome. The complex tapestry of these overlapping and intersecting clinical observations will be unfolded in the light of their chronology.

Sildenafil for portopulmonary hypertension in a patient undergoing liver transplantation

Liver transplantation (LT) may be indicated in cirrhotic patients with underlying pulmonary artery hypertension. However, severe pulmonary artery hypertension with mean pulmonary artery pressure (mPAP) above 50 mmHg has even been considered a contraindication to LT. We present a cirrhotic patient with an mPAP of 56 mmHg measured using right heart catheterization (RHC) and with severely compromised physical capacity. She was first treated with sildenafil (Viagra), a potent novel vasodilator, and successfully transplanted later. The mPAP decreased with sildenafil to the level of 28-31 mmHg and her general condition improved markedly. An LT using piggyback technique was performed 16 weeks later. Despite 2 reoperations for bleeding, the outcome has been excellent. In conclusion, treatment of severe portopulmonary hypertension (PHT) with sildenafil is effective. If a decrease in mPAP is achieved with sildenafil, it may improve the result of LT, even though no evidence of reversibility of PPHTN exists.

Portopulmonary hypertension and hepatopulmonary syndrome

The clinically and pathophysiologically distinct entities of portopulmonary hypertension and hepatopulmonary syndrome occur in a substantial proportion of patients who have advanced liver disease of different causes. These disorders are notoriously underdiagnosed, but they have a substantial impact on survival and require focused treatment. Abnormal intrapulmonary vascular dilatation, the hallmark of hepatopulmonary syndrome, can cause profound hypoxaemia that can be very difficult to treat. By contrast, portopulmonary hypertension results from excessive pulmonary vasoconstriction and vascular remodelling that eventually leads to right-heart failure. Insights into the pathogeneses of these syndromes have led to novel therapeutic approaches. However, in severely affected patients, effective treatment remains a difficult task. In selected patients, liver transplantation represents the only treatment option, but the decision to do isolated liver transplantation is particularly challenging in patients who have severe pulmonary disease involvement. Data from several centres have contributed to provide criteria that allow improved prediction of which patients may, or may not, benefit from liver transplantation alone.