Portal hypertension: Etiology, evaluation, and management

Endoscopic ultrasound in portal hypertension: navigating venous hemodynamics and treatment efficacy

Portal hypertension-related complications increase mortality in patients, irrespective of its etiology. Classically, endoscopic ultrasound (EUS) was used to assess the portal venous system and collaterals, considering size and hemodynamic parameters, which correlate with portal hypertension (PH) and related complications. Furthermore, therapeutic EUS guides treatment interventions, such as embolization of the gastric varices through coil placement and tissue adhesive injection, yielding encouraging clinical results. Recently, the direct measurement of portal pressure, emerging as an alternative to hepatic venous pressure gradient, has shown promise, and further research in this area is anticipated. In this review, we aimed to provide a detailed description of various possibilities for diagnosing vascular anatomy and hemodynamics in PH and actual knowledge on the EUS usefulness for PH vessel-related complications. Also, future promises for this field of endo-hepatology are discussed.

Predicting High-Risk Esophageal Varices in Cirrhosis: A Multi-Parameter Splenic CT Study

RATIONALE AND OBJECTIVES

To explore the value of splenic hemodynamic parameters from low-dose one-stop dual-energy and perfusion CT (LD-DE&PCT) in non-invasively predicting high-risk esophageal varices (HREV) in cirrhotic patients.

METHODS

We retrospectively analyzed cirrhotic patients diagnosed with esophageal varices (EV) through clinical, laboratory, imaging, and endoscopic examinations from September 2021 to December 2023 in our hospital. All patients underwent LD-DE&PCT to acquire splenic iodine concentration and perfusion parameters. Radiation dose was recorded. Patients were classified into non-HREV and HREV groups based on endoscopy. Univariate and multivariate logistic regression analysis were performed, and the prediction model for HREV was constructed. P < 0.05 was considered statistically significant.

RESULTS

Univariate analysis revealed that significant differences were found in portal iodine concentration (PIC), blood flow (BF), permeability surface (PS), spleen volume (V-S), total iodine concentration (TIC), and total blood volume of the spleen (BV-S) between groups. TIC demonstrated the highest predictive value with an area under the curve (AUC) value of 0.87. Multivariate analysis showed that PIC, PS, and BV-S were independent risk factors for HREV. The logistic regression model for predicting HREV had an AUC of 0.93. The total radiation dose was 20.66 ± 4.07 mSv.

CONCLUSION

Splenic hemodynamic parameters obtained from LD-DE&PCT can non-invasively and accurately assess the hemodynamic status of the spleen in cirrhotic patients with EV and predict the occurrence of HREV. Despite the retrospective study design and limited sample size of this study, these findings deserve further validation through prospective studies with larger cohorts.

Outcomes of Patients with Severe Obesity and Cirrhosis with Portal Hypertension Undergoing Bariatric Surgery: a Systematic Review

PURPOSE

Thus far, little attention has been paid to bariatric surgery (BS) in patients with severe obesity (SO) and cirrhosis with portal hypertension (PH). To address this knowledge gap, we systematically reviewed the available literature and evidence about BS in patients with SO and cirrhosis with PH. We inform on the perioperative and long-term outcomes of this intervention.

MATERIALS AND METHODS

Articles were identified in MEDLINE, SCOPUS, LILACS, and SCIELO, and included if they analyzed SO patients with clinically significant PH and reported the characteristics and outcomes of BS.

RESULTS

Six articles, including 32 patients, were included. The most frequent type of BS was sleeve gastrectomy performed in 27 patients. Perioperative transfusions were often not required, with only one case report describing the use of 1 unit of packed red blood cells post-operatively. Neither intraoperative nor post-op deaths were reported. All patients reported significant weight loss with improvements in comorbidities during the follow-up periods. Overall, 27 out of 29 patients had T2DM resolution, and 13 out of 23 had arterial hypertension resolution. One study reported improvements in the parameters of fibroscan.

CONCLUSION

This systematic review described the outcomes of BS among patients with SO with cirrhosis and PH. Performing this kind of surgery among these patients appears safe and associated with acceptable perioperative and long-term outcomes. However, further studies are required to provide evidence-based, strong recommendations.

The role of microRNAs on the pathogenesis, diagnosis and management of portal hypertension in patients with chronic liver disease

INTRODUCTION

Portal hypertension (PH) is the elevated pressure in the portal vein, which results in poor functioning of the liver and is influenced by various factors like liver cirrhosis, nonalcoholic fatty liver disease, schistosomiasis, thrombosis, and angiogenesis. Though the diagnosis and treatment have been advanced, early diagnosis of the disease remains a challenge, and the diagnosis methods are often invasive. Hence, the clear understanding of the molecular mechanisms of PH can give rise to the development of novel biomarkers which can pave way for early diagnosis in noninvasive methods, and also the identification of target genes can elucidate an efficient therapeutic target.

AREAS COVERED

PubMed and Embase database was used to search articles with search terms 'Portal Hypertension' or 'pathophysiology' and 'diagnosis' and 'treatment' or "role of miRNAs in portal hypertension.

EXPERT OPINION

Interestingly, biomarkers like microRNAs (miRNAs) have been studied for their potential role in various diseases including hypertension. In recent years, miRNAs have been proved to be an efficient biomarker and therapeutic target and few studies have assessed the roles of miRNAs in PH. The present paper highlights the potential roles of miRNAs in PH.

A rare case of congenital aneurysm of the portal system at level of spleno-porto-mesenteric confluence complicated by massive thrombosis

Portal venous aneurysm is a rare and potential dangerous vascular pathology, which can result in thrombosis or rupture. It may be congenital or acquired. Acquired form can be related mainly to portal hypertension, chronic hepatic disease, and trauma. We present a peculiar case of a congenital aneurysm involving the hepatic portal system in nearly all its extra-hepatic components: the main portal trunk, the spleno-porto-mesenteric confluence and the distal segment of splenic, superior, and inferior mesenteric veins, in a 20-year-old male patient. The aneurysm was complicated by massive thrombosis in absence of further predisposing factors.

A unique case of bleeding from esophageal varices as the first sign of essential thrombocythemia

Upper gastrointestinal bleeding (UGIB) is a common cause of hospital admission and variceal hemorrhage is responsible for many UGIB cases. Esophageal and gastric varices are caused by portal hypertension (PHT), mostly due to liver cirrhosis. Portal vein thrombosis (PVT) is an important cause of non-cirrhotic PHT and can be associated with several diseases, including myeloproliferative disorders such as essential thrombocythemia (ET). PVT may become apparent due to complications of PHT, including variceal bleeding (VB). We report the case of a 43-year-old male admitted with esophageal VB. Etiologic work-up for chronic liver disease was negative and abdominal magnetic resonance imaging revealed chronic PVT with cavernous transformation and a non-cirrhotic liver. JAK2 mutation was found, and the bone-marrow biopsy was consistent with ET, without peripheral blood alterations. This is a unique case of ET diagnosed in a variceal bleeding setting, remembering the necessity for high clinical suspicion.

Idiopathic Non-Cirrhotic Portal Hypertension and Porto-Sinusoidal Vascular Disease: Review of Current Data

Idiopathic non-cirrhotic portal hypertension (INCPH) is a clinicopathologic disease entity characterized by the presence of clinical signs and symptoms of portal hypertension (PH) in the absence of liver cirrhosis or known risk factors accountable for PH. Multiple hematologic, immune-related, infectious, hereditary and metabolic risk factors have been associated with this disorder. Still, the exact etiopathogenesis is largely unknown. The recently proposed porto-sinusoidal vascular disease (PSVD) scheme broadens the spectrum of the disease by also including patients without clinical PH who are found to have similar histopathologic findings on core liver biopsies. Three histomorphologic lesions have been identified as specific for PSVD to include obliterative portal venopathy, nodular regenerative hyperplasia and incomplete septal cirrhosis/fibrosis. However, these findings are often subtle, under-recognized and subjective with low interobserver agreement among pathologists. Additionally, the natural history of the subclinical forms of the disease remains unexplored. The clinical course is more favorable compared to cirrhosis patients, especially in the absence of clinical PH or liver dysfunction. There are no universally accepted guidelines in regard to diagnosis and treatment of INCPH/PSVD. Hence, this review emphasizes the need to raise awareness of this entity by highlighting its complex pathophysiology and clinicopathologic associations. Lastly, formulation of standardized diagnostic criteria with clinical validation is necessary to avoid misclassifying vascular diseases of the liver and to develop and implement targeted therapeutic strategies.

A rare complication of severe acute pancreatitis: portal vein compression resulting in an uncontrollable gastric ulcer bleeding

A 43-year-old male with a diagnosis of severe acute pancreatitis (SAP) was admitted to our hospital. After receiving the step-up approach for three weeks, the patient had a sudden hematemesis (nearly 400 ml). Gastroscopy and computed tomography (CT) were performed on the same day, revealing a gastric ulcer with a hemorrhage and the portal vein was extremely compressed by peripancreatic fluid collections in the retroperitoneal space.

Phosphodiesterases in the Liver as Potential Therapeutic Targets of Cirrhotic Portal Hypertension

Liver cirrhosis is a frequent condition with high impact on patients' life expectancy and health care systems. Cirrhotic portal hypertension (PH) gradually develops with deteriorating liver function and can lead to life-threatening complications. Other than an increase in intrahepatic flow resistance due to morphological remodeling of the organ, a functional dysregulation of the sinusoids, the smallest functional units of liver vasculature, plays a pivotal role. Vascular tone is primarily regulated by the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway, wherein soluble guanylate cyclase (sGC) and phosphodiesterase-5 (PDE-5) are key enzymes. Recent data showed characteristic alterations in the expression of these regulatory enzymes or metabolite levels in liver cirrhosis. Additionally, a disturbed zonation of the components of this pathway along the sinusoids was detected. This review describes current knowledge of the pathophysiology of PH with focus on the enzymes regulating cGMP availability, i.e., sGC and PDE-5. The results have primarily been obtained in animal models of liver cirrhosis. However, clinical and histochemical data suggest that the new biochemical model we propose can be applied to human liver cirrhosis. The role of PDE-5 as potential target for medical therapy of PH is discussed.

Biology of portal hypertension

Portal hypertension develops as a result of increased intrahepatic vascular resistance often caused by chronic liver disease that leads to structural distortion by fibrosis, microvascular thrombosis, dysfunction of liver sinusoidal endothelial cells (LSECs), and hepatic stellate cell (HSC) activation. While the basic mechanisms of LSEC and HSC dysregulation have been extensively studied, the role of microvascular thrombosis and platelet function in the pathogenesis of portal hypertension remains to be clearly characterized. As a secondary event, portal hypertension results in splanchnic and systemic arterial vasodilation, leading to the development of a hyperdynamic circulatory syndrome and subsequently to clinically devastating complications including gastroesophageal varices and variceal hemorrhage, hepatic encephalopathy from the formation of portosystemic shunts, ascites, and renal failure due to the hepatorenal syndrome. This review article discusses: (1) mechanisms of sinusoidal portal hypertension, focusing on HSC and LSEC biology, pathological angiogenesis, and the role of microvascular thrombosis and platelets, (2) the mesenteric vasculature in portal hypertension, and (3) future directions for vascular biology research in portal hypertension.

Recent advances in the management of variceal bleeding

Acute haemorrhage from ruptured gastroesophageal varices is perhaps the most serious consequence of uncontrolled portal hypertension in cirrhotic patients. It represents a medical emergency and is associated with a high morbidity and mortality. In those who survive the initial bleeding event, the risks of further bleeding and other decompensated events remain high. The past 30 years have seen a slow evolution of management strategies that have greatly improved the chances of surviving a variceal haemorrhage. Liver cirrhosis is a multi-staged pathological process and we are moving away from a one-size-fits-all therapeutic approach. Instead there is an increasing recognition that a more nuanced approach will yield optimal survival for patients. This approach seeks to risk stratify patients according to their disease stage. The exact type and timing of treatment offered can then be varied to suit individual patients. At the same time, the toolbox of available therapy is expanding and there is a continual stream of emerging evidence to support the use of endoscopic and pharmacological therapies. In this review, we present a summary of the treatment options for a variety of different clinical scenarios and for when there is failure to control bleeding. We have conducted a detailed literature review and presented up-to-date evidence from either primary randomized-controlled trials or meta-analyses that support current treatment algorithms.