Role of Transjugular Intrahepatic Portosystemic Shunts in the Management of Hepatopulmonary Syndrome: A Systemic Literature Review

Disruption of Hepatic Sinusoidal Homeostasis Leads to Hepatopulmonary Syndrome

Hepatopulmonary syndrome (HPS) is a pulmonary vascular complication of liver disease and/or portal hypertension. HPS manifests as impaired gas exchange and hypoxemia due to intrapulmonary vascular dilatations and shunts. In response to primary liver disease, the abnormal adaptation of respiratory epithelial cells, pulmonary endothelial cells and immune cells leads to pulmonary microenvironment disequilibrium and HPS. In this review, we explore the pathophysiologic mechanisms of HPS, including vascular dilation, angiogenesis and alveolar dysfunction. The liver is the primary contributor to HPS, and liver transplantation is the only treatment that generally reverses HPS. We then discuss how disruption of hepatic sinusoidal homeostasis may impact the progression of HPS, mainly focusing on hepatocytes, cholangiocytes, LSECs and macrophages. As HPS occurs more commonly in advanced liver cirrhosis, we also discuss that normalisation of liver dysfunction and portal hypertension is crucial for the resolution of HPS. In conclusion, liver-targeted therapies may be effective in treating HPS.

High Prevalence and Clinical Relevance of Intrapulmonary Vascular Dilatations in Patients Undergoing TIPS Implantation

BACKGROUND & AIMS

Considerate patient selection is vital to ensure the best possible outcomes after transjugular intrahepatic portosystemic shunt (TIPS) insertion. However, data regarding the impact of intrapulmonary vascular dilatations (IPVDs) or hepatopulmonary syndrome (HPS) on the clinical course after TIPS implantation is lacking. Hence, this study aimed to investigate the relevance of IPVD and HPS in patients undergoing TIPS implantation.

METHODS

Contrast enhanced echocardiography and blood gas analysis were utilized to determine presence of IPVD and HPS. Multivariable competing risk analyses were performed to evaluate cardiac decompensation (CD), hepatic decompensation (HD), and liver transplant (LTx)-free survival within 1 year of follow-up.

RESULTS

Overall, 265 patients were included, of whom 136 had IPVD and 71 fulfilled the HPS criteria. Patients with IPVD had lower Freiburg index of post-TIPS survival (FIPS) scores, lower creatinine, and more often received TIPS because of variceal bleeding. Presence of IPVD was associated with a significantly higher incidence of CD (hazard ratio [HR], 1.756; 95% confidence interval [CI], 1.011-3.048; P = .046) and HD (HR, 1.841; 95% CI, 1.255-2.701; P = .002). However, LTx-free survival was comparable between patients with and without IPVD (HR, 1.081; 95% CI, 0.630-1.855; P = .780). Patients with HPS displayed a trend towards more CD (HR, 1.708; 95% CI, 0.935-3.122; P = .082) and HD (HR, 1.458; 95% CI, 0.934-2.275; P = .097) that failed to reach statistical significance. LTx-free survival did not differ in those with HPS compared with patients without HPS, respectively (HR, 1.052; 95% CI, 0.577-1.921; P = .870).

CONCLUSION

Screening for IPVD before TIPS implantation could help to further identify patients at higher risk of CD and HD.

Chinese Society of Gastroenterology, Chinese Medical Association. Chinese consensus on the management of liver cirrhosis

Liver cirrhosis, characterized by diffuse necrosis, insufficient regeneration of hepatocytes, angiogenesis, severe fibrosis, and the formation of pseudolobules, is a progressive, chronic liver disease induced by a variety of causes. It is clinically characterized by liver function damage and portal hypertension, and many complications may occur in its late stage. Based on the updated practice guidelines, expert consensuses, and research advances on the diagnosis and treatment of cirrhosis, the Chinese Society of Gastroenterology of Chinese Medical Association established the current consensus to standardize the clinical diagnosis and management of liver cirrhosis and guide clinical practice. This consensus contains 43 statements on the etiology, pathology and pathogenesis, clinical manifestations, major complications, diagnosis, treatment, prognosis, and chronic disease control of liver cirrhosis. Since several practice guidelines and expert consensuses on the complications of liver cirrhosis have been published, this consensus emphasizes the research progress of liver cirrhosis itself.

Budd-Chiari syndrome in children: Challenges and outcome

Budd-Chiari syndrome (BCS) is an uncommon disease of the liver, characterised by obstruction of the hepatic venous outflow tract. The etiological spectrum of BCS as well as venous obstruction pattern show wide geographical and demographic variations across the globe. Compared to adults with BCS, children have primary BCS as the predominant etiology, earlier clinical presentation, and hence better treatment outcome. Underlying prothrombotic conditions play a key role in the etiopathogenesis of BCS, though work-up for the same is often unyielding in children. Use of next-generation sequencing in addition to conventional tests for thrombophilia leads to better diagnostic yield. In recent years, advances in radiological endovascular intervention techniques have revolutionized the treatment and outcome of BCS. Various non-invasive markers of fibrosis like liver and splenic stiffness measurement are being increasingly used to assess treatment response. Elastography techniques provide a novel non-invasive tool for measuring liver and splenic stiffness. This article reviews the diagnostic and therapeutic advances and challenges in children with BCS.

North American Practice-Based Recommendations for Transjugular Intrahepatic Portosystemic Shunts in Portal Hypertension

Complications of portal hypertension, including ascites, gastrointestinal bleeding, hepatic hydrothorax, and hepatic encephalopathy, are associated with significant morbidity and mortality. Despite few high-quality randomized controlled trials to guide therapeutic decisions, transjugular intrahepatic portosystemic shunt (TIPS) creation has emerged as a crucial therapeutic option to treat complications of portal hypertension. In North America, the decision to perform TIPS involves gastroenterologists, hepatologists, and interventional radiologists, but TIPS creation is performed by interventional radiologists. This is in contrast to other parts of the world where TIPS creation is performed primarily by hepatologists. Thus, the successful use of TIPS in North America is dependent on a multidisciplinary approach and technical expertise, so as to optimize outcomes. Recently, new procedural techniques, TIPS stent technology, and indications for TIPS have emerged. As a result, practices and outcomes vary greatly across institutions and significant knowledge gaps exist. In this consensus statement, the Advancing Liver Therapeutic Approaches group critically reviews the application of TIPS in the management of portal hypertension. Advancing Liver Therapeutic Approaches convened a multidisciplinary group of North American experts from hepatology, interventional radiology, transplant surgery, nephrology, cardiology, pulmonology, and hematology to critically review existing literature and develop practice-based recommendations for the use of TIPS in patients with any cause of portal hypertension in terms of candidate selection, procedural best practices and, post-TIPS management; and to develop areas of consensus for TIPS indications and the prevention of complications. Finally, future research directions are identified related to TIPS for the management of portal hypertension.

Expanding Indications of TIPS in the Management of Portal Hypertension Complications

Transjugular intrahepatic portosystemic shunt (TIPS) is a nonsurgical intervention to reduce portal pressure by creating a low-resistance channel between the portal and systemic circulations. It is a well-accepted treatment for gastroesophageal varices and refractory ascites. This review aims to discuss the evidence-based applications of TIPS in other complications of portal hypertension beyond gastroesophageal varices and refractory ascites.

Transjugular intrahepatic portosystemic shunts in portal vein thrombosis: A review

The presence of portal vein thrombosis (PVT) has previously been considered a contraindication to the insertion of transjugular intrahepatic portosystemic shunts (TIPSS). However, patients with PVT may have portal hypertension complications and may thus benefit from TIPSS to reduce portal venous pressure. There is an increasing body of literature that discusses the techniques and outcomes of TIPSS in PVT. This review summarizes the techniques, indications and outcomes of TIPSS in PVT in published case reports, case series and comparative trials, especially regarding the reduction in portal hypertensive complications such as variceal bleeding. A comprehensive literature search was conducted using MEDLINE and PubMed databases. Manuscripts published in English between 1 January 1990 and 1 March 2021 were used. Abstracts were screened and data from potentially relevant articles analyzed. TIPSS in PVT has been reported with high levels of technical success, short-term portal vein recanalization and long-term PV patency and TIPSS patency outcomes. Several comparative studies, including randomized controlled trials, have shown favorable outcomes of TIPSS compared with non-TIPSS treatment of PVT complications. Outcomes of TIPSS with PVT appear similar to those in TIPSS without PVT. However, TIPSS may be more technically difficult in the presence of PVT, and such procedures should be performed in expert high-volume centers to mitigate the risk of procedural complications. The presence of PVT should no longer be considered a contraindication to TIPSS. TIPSS for PVT has been acknowledged as a therapeutic strategy in recent international guidelines, although further studies are needed before recommendations can be strengthened. KEY POINTS: Portal vein thrombosis (PVT) is no longer a contraindication to the insertion of transjugular intrahepatic portosystemic shunts (TIPSS) TIPSS often leads to the spontaneous dissolution of PVT, but can be combined with mechanical or pharmacological thrombectomy TIPSS reduces portal hypertensive complications of PVT, such as variceal bleeding, and can also facilitate liver transplantation where PVT may otherwise interfere with vascular anastomoses Studies have shown favorable long-term outcomes of TIPSS compared with TIPSS without PVT; as well as compared with non-TIPSS treatment of PVT complications TIPSS in PVT should be performed in high-volume specialist centers due to technical difficulties.

Transjugular intrahepatic portosystemic shunt in cirrhosis: An exhaustive critical update

More than five decades after it was originally conceptualized as rescue therapy for patients with intractable variceal bleeding, the transjugular intrahepatic portosystemic shunt (TIPS) procedure continues to remain a focus of intense clinical and biomedical research. By the impressive reduction in portal pressure achieved by this intervention, coupled with its minimally invasive nature, TIPS has gained increasing acceptance in the treatment of complications of portal hypertension. The early years of TIPS were plagued by poor long-term patency of the stents and increased incidence of hepatic encephalopathy. Moreover, the diversion of portal flow after placement of TIPS often resulted in derangement of hepatic functions, which was occasionally severe. While the incidence of shunt dysfunction has markedly reduced with the advent of covered stents, hepatic encephalopathy and instances of early liver failure continue to remain a significant issue after TIPS. It has emerged over the years that careful selection of patients and diligent post-procedural care is of paramount importance to optimize the outcome after TIPS. The past twenty years have seen multiple studies redefining the role of TIPS in the management of variceal bleeding and refractory ascites while exploring its application in other complications of cirrhosis like hepatic hydrothorax, portal hypertensive gastropathy, ectopic varices, hepatorenal and hepatopulmonary syndromes, non-tumoral portal vein thrombosis and chylous ascites. It has also been utilized to good effect before extrahepatic abdominal surgery to reduce perioperative morbidity and mortality. The current article aims to review the updated literature on the status of TIPS in the management of patients with liver cirrhosis.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Refractory ascites-the contemporary view on pathogenesis and therapy

Refractory ascites (RA) refers to ascites that cannot be mobilized or that has an early recurrence that cannot be prevented by medical therapy. Every year, 5-10% of patients with liver cirrhosis and with an accumulation of fluid in the peritoneal cavity develop RA while undergoing standard treatment (low sodium diet and diuretic dose up to 400 mg/day of spironolactone and 160 mg/day of furosemide). Liver cirrhosis accounts for marked alterations in the splanchnic and systemic hemodynamics, causing hypovolemia and arterial hypotension. The consequent activation of renin-angiotensin and sympathetic systems and increased renal sodium re-absorption occurs during the course of the disease. Cirrhotic patients with RA have poor prognoses and are at risk of developing serious complications. Different treatment options are available, but only liver transplantation may improve the survival of such patients.

Changes in arterial oxygenation after portal decompression in Budd-Chiari syndrome patients with hepatopulmonary syndrome

OBJECTIVES

To evaluate the changes in arterial oxygenation after portal decompression in Budd-Chiari syndrome (BCS) patients with hepatopulmonary syndrome (HPS).

METHODS

From June 2014 to June 2015, all patients with BCS who underwent balloon angioplasty or transjugular intrahepatic portosystemic shunt (TIPS) creation at our institution were eligible for inclusion in this study. Arterial blood gas analysis was performed with the patient in an upright position and breathing room air at 2-3 days and 1 and 3 months after the procedure.

RESULTS

Eleven patients with HPS and 14 patients without HPS were included in this study. The procedure was technically successful in 24 patients. One patient with HPS had technically unsuccessful TIPS creation. Reobstruction or TIPS dysfunction was not detected in any patient within 3 months after the procedure. For patients with HPS, the alveolar-arterial oxygen gradient (A-aO2) remained comparable to baseline 2-3 days after the procedure (-3.2 ± 11.9 mmHg; p = .412), significantly improved 1 month after the procedure (-11.7 ± 6.4 mmHg; p < .001), and then returned to baseline 3 months after the procedure (-1.3 ± 12.5 mmHg; p = .757). For patients without HPS, the A-aO2 remained comparable to baseline at all three time points after the procedure (+1.4 ± 8.3 mmHg, +3.5 ± 8.1 mmHg, and +1.3 ± 8.2 mmHg; p = .543, p = .137, and p = .565).

CONCLUSIONS

Arterial oxygenation transiently improves after portal decompression in BCS patients with HPS.

KEY POINTS

• Intrapulmonary vascular dilation and hepatopulmonary syndrome are common in patients with Budd-Chiari syndrome. • Arterial oxygenation transiently improves after portal decompression in Budd-Chiari syndrome patients with hepatopulmonary syndrome.

Portal Hypertension and Related Complications: Diagnosis and Management

Portal hypertension is a major complication of cirrhosis, and its consequences, including ascites, esophageal varices, hepatic encephalopathy, and hepatorenal syndrome, lead to substantial morbidity and mortality. The past several decades have seen major improvements in the clinical management of complications of portal hypertension, resulting in substantial gains in patient outcomes. However, important challenges remain. This review focuses on the pathophysiology and diagnosis of portal hypertension and discusses general approaches in the management of patients with ascites as a result of portal hypertension.

Chronic Hepatitis C with Cyanosis

Background

There are multiple aetiologies for dyspnea in patients with liver disease, including pneumonia, pulmonary embolism, hepatic hydrothorax, portopulmonary syndrome, and hepatopulmonary syndrome. The aim of this paper is to emphasize the importance of early diagnosis and management of hepatopulmonary syndrome.

Case Presentation

We report a case of a 65-year-old male who was known to have chronic hepatitis C presented with one-year history of shortness of breath and cyanosis. The initial impression of pulmonary embolism was excluded by comprehensive diagnostic investigations. The correlation between the clinical picture and investigations raised the possibility of hepatopulmonary syndrome which was confirmed by contrast-enhanced transthoracic echocardiography.

Conclusions

High suspicion is required to diagnose hepatopulmonary syndrome in patients with liver disease and hypoxemia. Screening for this complication is appropriate in liver transplant candidates, and diagnosed patients should be evaluated extensively for liver transplant.

Effect of Transjugular Intrahepatic Portosystemic Shunt Creation on Pulmonary Gas Exchange in Patients with Hepatopulmonary Syndrome: A Prospective Study

PURPOSE

To evaluate effect of transjugular intrahepatic portosystemic shunt (TIPS) creation on pulmonary gas exchange in patients with hepatopulmonary syndrome (HPS).

MATERIALS AND METHODS

All patients with cirrhosis or Budd-Chiari syndrome undergoing elective TIPS creation at a single institution between June 2014 and June 2015 were eligible for inclusion. Twenty-three patients with HPS (age 55.0 y ± 14.4; 11 men; Model for End-Stage Liver Disease score 10.2 ± 2.7) who achieved technical success were included in the analysis. Diagnosis of HPS was established by contrast-enhanced echocardiography demonstrating intrapulmonary vascular dilatation and arterial blood gas analysis demonstrating arterial oxygenation defects.

RESULTS

Mean portosystemic gradient was reduced from 21.7 mm Hg ± 8.3 before TIPS creation to 10.8 mm Hg ± 5.1 after TIPS creation. Among the 5 (21.7%) patients who experienced dyspnea, 4 (80.0%) reported improvement after TIPS creation. This improvement was not maintained at 3 months after TIPS creation in 2 (50.0%) patients. Compared with before TIPS creation, mean change in alveolar-arterial oxygen gradient for patients with HPS was statistically significant at 1 month (-9.2 mm Hg ± 8.0; P < .001) after TIPS creation, but not at 2-3 days (-0.9 mm Hg ± 10.5; P = .678) or 3 months (-3.4 mm Hg ± 11.8; P = .179) after TIPS creation.

CONCLUSIONS

TIPS creation can transiently improve pulmonary gas exchange in patients with HPS.

Platypnea-orthodeoxia Syndrome in a Patient with Cryptogenic Liver Cirrhosis: An Elusive Cause of Hypoxemia

Platypnea-orthodeoxia syndrome (POS) has been defined as shortness of breath and hypoxemia in the upright position that improves with dorsal decubitus. This is a rare disorder caused by right-to-left shunts due to a persistent foramen ovale or pulmonary arteriovenous malformations. Hepatopulmonary syndrome can present with POS in the presence of pulmonary vasodilation and pulmonary arteriovenous communications in patients with liver disease. We report a case where the diagnosis of POS was made incidentally in a patient with cryptogenic liver cirrhosis. After other causes of hypoxemia were excluded, the diagnosis of right-to-left pulmonary shunt was confirmed by late opacification of the left heart chambers seen in a transthoracic echocardiogram. Interestingly, computerized tomography (CT) of the chest with contrast demonstrated a very prominent pulmonary vascular pattern extending to the periphery of the lungs. POS is a rare cause of hypoxemia that requires a high level of suspicion, and exclusion of more common causes of hypoxemia.

Clinical efficacy of transjugular intrahepatic portosystemic shunt in the treatment of hepatopulmonary syndrome

Transjugular intrahepatic portosystemic shunt (TIPS) reduces the portal venous pressure of patients with hepatopulmonary syndrome (HPS).To describe the patients who underwent TIPS for the treatment of HPS.A retrospective study was performed on 81 patients with HPS and gastrointestinal hemorrhage treated with TIPS. Thirty patients underwent TIPS through the main portal vein (group A), 24 through the left branch of the portal vein (group B), and 27 through the right branch of the portal vein (group C). The partial pressure of arterial oxygen (PaO2), alveolar-to-arterial oxygen partial pressure gradient (A-aPO2), oxygen saturation (SO2), and complications were recorded and compared. The survival rate for each group was calculated.The technical success rate was 100% in the 3 groups. Preoperative portal vein pressure showed no significant differences between the 3 groups, which was decreased post-TIPS operation. In group A, PaO2 and SO2 were higher in 15 days and 3 months postoperative than preoperative (P < .05), whereas A-aPO2 was lower (P < .05). No difference occurred between 12 months post- and preoperative group. In group C, PaO2 and SO2 did not alter significantly at each time point after operation (P > .05), whereas A-aPO2 decreased at 3 months (P = .041) than preoperative. In group B, all indicators at each follow-up time point after TIPS were improved significantly as compared with the preoperative group (P < .05), which showed an excellent effect on hypoxemia treatment. Although the 1-year survival rate of 3 groups of patients was 92.85%, 90.90%, and 91.67%, respectively, the rate of hepatic encephalopathy and hepatic myelopathy was 33.33% (10/30), 16.67% (4/24), and 33.33% (9/27) after TIPS.TIPS reduced the pressure of the portal vein effectively and alleviated hypoxemia in most HPS patients successfully. Thus, the left branch of the portal vein is optimal for TIPS owing to fewer complications and efficacy in improving PaO2 as compared with the main portal vein and right branch.

Emerging hepatic syndromes: pathophysiology, diagnosis and treatment

Liver cirrhosis is a major cause of morbidity and mortality worldwide, mainly due to complications of portal hypertension. In this article, we review the current understanding on the pathophysiology, the diagnostic criteria and the available therapeutic options for patients with emerging hepatic syndromes in cirrhosis, namely the hepatorenal, hepato-adrenal and hepatopulmonary syndrome. The hepatorenal syndrome is a well-recognized complication of advanced cirrhosis and is usually associated with an accelerated course to death unless liver transplantation is performed. The hepatopulmonary syndrome is often missed in the evaluation of patients with cirrhosis; however, early recognition is essential for the efficient management of individual patients. The hepato-adrenal syndrome, although not fully characterized, offers an exciting field for research and potential therapeutic interventions.